# Sikkelee v. Precision Airmotive Corporation

> District Court, M.D. Pennsylvania · February 4, 2021

URL: https://www.frixlaw.com/law-library/cases/10409817

## Case

- **Court:** District Court, M.D. Pennsylvania
- **Decided:** February 4, 2021
- **Opinion:** 100trialcourt
- **Cited by:** 0 later opinions in the Frix Law Library

## Citator (automated)

- No negative treatment found by the automated citator. That is not the same as a confirmation that the case is good law; read the citing cases.
- Full citator and citing cases: https://www.frixlaw.com/law-library/cases/10409817

## How later opinions describe it (automated extraction)

- holding that substitute “opinion should not stray from the subject matter of [the original] opinion. To the extent that [replacement expert] covers new material in his deposition, Defendant may file a motion to exclude that portion of [the] opinion”
- noting that two decades of experience as a narcotics officer qualified an individual “to testify as an expert on narcotics”
- noting that the Third Circuit “interpret[s] the specialized knowledge requirement liberally” (internal quotation marks omitted)

## Opinion text

IN THE UNITED STATES DISTRICT COURT
FOR THE MIDDLE DISTRICT OF PENNSYLVANIA

JILL SIKKELEE, Individually and as No. 4:07-CV-00886
Personal Representative of the Estate of
David Sikkelee, Deceased, (Judge Brann)

Plaintiff,

v.

PRECISION AIRMOTIVE
CORPORATION, et al.,

Defendants.

MEMORANDUM OPINION

FEBRUARY 4, 2021
I. BACKGROUND
In 2007, Jill Sikkelee filed a complaint related to the 2005 death of her
husband, David Sikkelee; that complaint was subsequently twice amended, most
recently in 2011.1 In the second amended complaint, Sikkelee alleges that Mr.
Sikkelee’s private plane crashed after the fasteners holding the plane’s MA-4SPA
model carburetor’s fuel bowl to its throttle body loosened, causing the engine to lose
power. She alleges that Lycoming Engines (“Lycoming”), a subsidiary of Avco
Corporation, designed, manufactured, and sold the engine that incorporated the
allegedly defective carburetor. Sikkelee further alleges that Lycoming was aware of

numerous problems and defects with the screws and locking mechanism that attach
the carburetor halves together but failed to correct those issues and instead covered

them up. Lycoming in turn argues that no mechanical issues contributed to the crash.
Rather, it asserts that Mr. Sikkelee tried to climb in altitude too quickly to avoid
mountains, which resulted in an aerodynamic stall that caused the plane to lose lift

and crash.
In 1969, Lycoming manufactured the engine installed on David Sikkelee’s
aircraft at the time of the accident. The engine underwent an overhaul in 2004, during
which an overhauled model MA-4SPA carburetor was installed on the airplane. The

carburetor was designed and manufactured by Marvel-Schebler and was overhauled
by Kelly Aerospace. Kelly Aerospace holds a Federal Aviation Administration
(FAA) Parts Manufacturer Approval (PMA) certificate2 and an FAA repair station

certificate authorizing it to manufacture replacement parts and repair and overhaul
carburetors independently of the engine manufacturer. During the 2004 carburetor
overhaul, Kelly Aerospace replaced a number of parts, including the fuel bowl
screws, lock tab washers, and fuel bowl gasket. The carburetor also included a

replacement throttle body and fuel bowl of unknown age, origin, and condition.3

2 An FAA PMA certification is a combined design and production approval for modification
and replacement articles. The design approval phase of the PMA process certifies that a
replacement or modification article complies with the airworthiness standards of eligible
products (aircraft, engine, or propeller). The applicant shows this compliance through tests and
computations unless the article is identical to the article design on a type-certificated product.
In 2014, this Court granted Lycoming partial summary judgment on the
ground that the FAA’s issuance of a type certificate for the engine meant that the

federal standard of care had been satisfied and Lycoming was not negligent or
strictly liable.4 The Court denied summary judgment on Sikkelee’s failure-to-warn
claims, which were based on Lycoming’s alleged violation of 14 C.F.R. § 21.3 based

on its failure to “report any failure, malfunction, or defect in any product, part,
process, or article” that Lycoming made.5
On appeal, the United States Court of Appeals for the Third Circuit held that
“field preemption does not apply to state-law aircraft products liability claims

because (1) ‘the Federal Aviation Act, the General Aviation Revitalization Act of
1994, and the regulations promulgated by the [FAA] reflect that Congress did not
intend to preempt aircraft products liability claims in a categorical way,’; (2)

‘Congress has not created a federal standard of care for persons injured by defective
airplanes,’; and (3) ‘the type certification process cannot as a categorical matter
displace the need for compliance in this context with state standards of care.’”6 The
Third Circuit thus held that “aircraft products liability cases like Sikkelee’s may

proceed using a state standard of care, subject to traditional principles of conflict

4 Doc. 495.
5 Id.
6 Sikkelee v. Precision Airmotive Corp., 907 F.3d 701, 708 (3d Cir. 2018) (quoting Sikkelee v.
preemption, including in connection with the specifications expressly set forth in a
given type certificate.”7

On remand, Lycoming again moved for summary judgment, asserting that
Sikkelee’s claims were subject to conflict preemption and would, in any event, fail
under Pennsylvania law. 8 This Court again granted summary judgment in

Lycoming’s favor, concluding that Sikkelee’s claims were conflict-preempted and,
even if they were not, Lycoming was entitled to summary judgment on Sikkelee’s
strict liability and negligence claims based on Pennsylvania law.9 Sikkelee again
appealed, and the Third Circuit again reversed in part, holding that this “Court erred

in concluding Sikkelee’s claims are conflict-preempted because Lycoming has not
produced clear evidence that the FAA would not have allowed it to change the
engine’s design as set forth in the type certificate. The Court also erred in granting

Lycoming summary judgment on Sikkelee’s strict liability and negligence claims
because there are genuine disputes of material fact concerning, among other things,
causation.”10
After this most recent remand, both parties replaced some of their expert

witnesses, Lycoming substituting: Randy Jensen for James Stabley for engine
investigations; Leslie Doud for Walter Voisard with respect to propeller

7 Id. (internal quotation marks omitted).
8 Doc. 534.
9 Doc. 565.
investigation; and Amy Gray for Merritt Birkey regarding chemistry and fire origin.
The parties have now filed numerous motions to strike or exclude expert testimony.

Sikkelee seeks to strike the opinions of: (1) Randy Jensen, Leslie Doud, and Amy
Gray;11 (2) Tom Eager;12 (3) Dale Alexander;13 (4) any propeller analysis and RPM
calculation from defense experts Jeffrey Edwards, Leslie Doud, and Randy Jensen;14
(5) any testimony from Jeffrey Edwards;15 and (6) any testimony from Michael

Dreikorn.16 Lycoming in turn seeks to strike Michael Schiefer17 and Donald E.
Sommer,18 and has moved to exclude as untimely the opinions of Donald Sommer
and Richard McSwain.19

On January 19, 2021, the Court held a hearing on the pending motions where
it heard testimony from the relevant experts. Having reviewed the briefs, expert
reports, and Daubert testimony, the Court concludes that the majority of arguments

concerning the expert opinions go to weight rather than admissibility and,
accordingly, the Daubert motions will largely be denied. Moreover, upon
consideration of the relevant factors concerning the admissibility of expert opinions

11 Doc. 606.
12 Doc. 608.
13 Doc. 610. In her motion, Sikkelee originally sought to strike portions of both Dale Alexander
and Gary Novak. However, during the Daubert hearing, Sikkelee clarified that she has no
objection to Novak’s opinion, and seeks to strike only Alexander’s opinion.
14 Doc. 612.
15 Doc. 614.
16 Doc. 648.
17 Doc. 616.
18 Doc. 618.
that were in some ways procedurally improper, the parties’ motions to strike will be
denied.

II. DISCUSSION
Federal Rules of Evidence 702 and 703 govern the admissibility of expert
testimony and set forth certain criteria for admissibility. Expanding upon those

Rules, the United States Supreme Court set forth the standard for admissibility of
expert testimony in Daubert v. Merrell Dow Pharm., Inc.20 The Court in Daubert
delegated to district courts a “gatekeeping responsibility” under Rule 702, which
requires that courts determine at the outset whether an expert witness may “testify

to (1) scientific knowledge that (2) will assist the trier of fact.”21 That gate-keeping
function demands an assessment of “whether the reasoning or methodology
underlying the testimony is scientifically valid” as well as “whether that reasoning
or methodology properly can be applied to the facts in issue.”22 A district court

“exercises more control over experts than over lay witnesses,” since “[e]xpert
evidence can be both powerful and quite misleading because of the difficulty in
evaluating it.”23

Following Daubert, the United States Court of Appeals for the Third Circuit
cast expert admissibility determinations in light of three basic requirements:

20 509 U.S. 579 (1993).
21 Id. at 592.
22 Id. at 592-93.
(1) qualification; (2) reliability; and (3) fit.24 The qualification prong demands that
the proffered expert possess sufficient “specialized knowledge” to testify as an

expert.25 To satisfy the reliability prong, an expert’s opinion “must be based on the
‘methods and procedures of science’ rather than on ‘subjective belief or unsupported
speculation.’”26 The Third Circuit has set forth eight non-exclusive factors that “a

district court should take into account” when deciding the reliability of expert
testimony:
(1) whether a method consists of a testable hypothesis; (2) whether the
method has been subject to peer review; (3) the known or potential rate
of error; (4) the existence and maintenance of standards controlling the
technique’s operation; (5) whether the method is generally accepted;
(6) the relationship of the technique to methods which have been
established to be reliable; (7) the qualifications of the expert witness
testifying based on the methodology; and (8) the non-judicial uses to
which the method has been put.27

With regard to the fit prong, the Third Circuit explained that admissibility “depends
. . . on the proffered connection between the scientific research or test result . . . and
[the] particular disputed factual issues.”28
The burden of proof for admissibility of expert testimony falls upon the party
that seeks to introduce the evidence. 29 However, as the Third Circuit has
emphasized, “[t]he test of admissibility is not whether a particular scientific opinion

24 In re Paoli R.R. Yard PCB Litig., 35 F.3d 717, 741-43 (3d Cir. 1994).
25 Id. at 741.
26 Id. at 742 (quoting Daubert, 509 U.S. at 589).
27 Id. at 742 n.8.
28 Id. at 743 (internal quotation marks omitted).
has the best foundation or whether it is demonstrably correct. Rather, the test is
whether the particular opinion is based on valid reasoning and reliable

methodology.”30
This standard is not intended to be a high one, nor is it to be applied in
a manner that requires the plaintiffs to prove their case twice—they do
not have to demonstrate to the judge by a preponderance of the evidence
that the assessments of their experts are correct, they only have to
demonstrate by a preponderance of evidence that their opinions are
reliable.31

District courts must always be cognizant of the fact that “[t]he analysis of the
conclusions themselves is for the trier of fact when the expert is subjected to cross-
examination.”32
A. Motions to Strike on Procedural Grounds
The parties have collectively filed three motions to strike various opinions on
procedural grounds. First, Sikkelee seeks to strike portions of Jensen, Doud, and
Gray’s opinions, as Sikkelee argues that portions of those opinions improperly
exceed the scope of the original expert reports.33 Second, Sikkelee argues that
Michael Dreikorn’s opinion should be stricken as untimely.34 Finally, Lycoming
seeks to exclude as untimely the opinions of Donald Sommer and Richard
McSwain.35

30 Id. (internal quotation marks omitted).
31 Id. (internal quotation marks omitted).
32 Id. (internal quotation marks omitted).
33 Doc. 607.
34 Doc. 649.
With respect to the question of whether untimely or otherwise procedurally
defective opinions should be admitted, although the Court has discretion to exclude

evidence in response to violations of pretrial disclosure deadlines, “exclusion of
critical evidence is an ‘extreme’ sanction, and thus, a district court’s discretion is not
unlimited. 36 Accordingly, in determining whether exclusion of evidence is
warranted, the Court should consider the five Pennypack37 factors:

(1) “the prejudice or surprise in fact of the party against whom the
excluded witnesses would have testified” or the excluded evidence
would have been offered; (2) “the ability of that party to cure the
prejudice”; (3) the extent to which allowing such witnesses or evidence
would “disrupt the orderly and efficient trial of the case or of other cases
in the court”; (4) any “bad faith or willfulness in failing to comply with
the court’s order”; and (5) the importance of the excluded evidence.
The importance of the evidence is often the most significant factor.38

i. Motion to Strike Randy Jensen, Leslie Doud, and Amy Gray
First, with respect to Sikkelee’s motion to strike Randy Jensen, Leslie Doud,
and Amy Gray, Sikkelee contends that all three experts offer opinions that
improperly exceed the scope of the original expert reports.39 As to Jensen, Sikkelee
argues that Lycoming’s original expert (James Stabley) did not examine or test the
carburetor in any way or offer an opinion as to “whether the carburetor

36 ZF Meritor, LLC v. Eaton Corp., 696 F.3d 254, 297 (3d Cir. 2012).
37 Meyers v. Pennypack Woods Home Ownership Ass’n, 559 F.2d 894 (3d Cir. 1977).
38 ZF Meritor, 696 F.3d at 298 (quoting Pennypack, 559 F.2d at 904-05).
malfunctioned . . . [or] address the effect of loose carburetor throttle body to bowl
screws on the engine’s operation.”40

With respect to Doud, Sikkelee asserts that the original expert (Walter
Voisard) opinion addressed only damage to the plane’s propeller to determine the
amount of power that was being provided to the propeller at the time of the crash,

whereas Doud examined other pieces of the propeller, calculated the airspeed of the
plane, examined propeller strike marks on the ground to determine speed and power
at the moment of impact, and compared those strike marks with strike marks in other
accidents.41 Finally, with respect to Gray, Sikkelee asserts that the original expert

(Merritt Birky) opined that aviation fuel was found on the outside of the carburetor
after the crash, whereas Gray opines that there “was no ‘abundance of fuel near the
carburetor’s exterior.’”42

Sikkelee argues that all three new expert opinions impermissibly exceed the
scope of the original expert opinions proffered by Lycoming, and they must
therefore be stricken.43 Lycoming responds that the new expert opinions encompass
the same subject matter as the original reports and are narrowly tailored to rebut

40 Id. at 3; see id. at 3-6. Although there was originally a dispute with respect to Jensen’s analysis
of screw thread damage, at the Daubert hearing Lycoming withdrew that portion of Jensen’s
opinion, which may render moot that portion of Sikkelee’s motion to exclude. Regardless, the
Court’s analysis under the Pennypack factors applies with equal force to this opinion.
41 Id. at 6-9.
42 Id. at 9.
Sikkelee’s expert and, in any event, exclusion is not warranted because Sikkelee is
not prejudiced by the reports, and the reports are critical to the defense.44

Essentially, Lycoming concedes that the new expert opinions vary from the
original opinions, but contends that such variation is normal and appropriate, as:
Lycoming could not require its substitute experts to reach specific
conclusions or apply particular methodology within their areas of
expertise. It is up to the experts, based on their training, qualifications,
and experience, to formulate opinions based on the record evidence and
their chosen methodology. Lycoming appropriately retained substitute
experts within the same areas of expertise as the prior experts . . .45

a. Whether the Opinions are New
The law is clear that “[t]he purpose of allowing substitution of an expert is to
put the movant in the same position it would have been in but for the need to change
experts; it is not an opportunity to designate a ‘better’ expert who holds differing or
more advantageous opinions than the first expert.”46 Thus, “in instances of expert
witness substitution[, courts will generally seek] to prevent prejudice by” ensuring
that the testimony is “substantively similar to the original expert’s opinions and
limited to the same matters.”47 Stated differently, substitute expert testimony should

44 Doc. 620.
45 Id. at 8.
46 Shipp v. Arnold, No. 4:18-CV-4017, 2019 WL 4040597, at *2 (W.D. Ark. Aug. 27, 2019).
47 Lefta Assocs., Inc. v. Hurley, No. 1:09-CV-2487, 2013 WL 12239510, at *2 (M.D. Pa. Feb.
be limited “to the subject matter and theories already espoused by the former
expert.”48

Despite these limitations, as other courts have emphasized, “the substitute
expert is not compelled to merely repeat the words of his or her predecessor. He or
she may use different language and even reach ‘slightly broader conclusions’ so long

as the new report is ‘substantially similar in all material respects’ to the previous
report.”49 This is true because, while a substitute expert “should not result in a
windfall for [the party offering the substitute expert], neither should it unfairly
disadvantage them.” 50 Accordingly, “the substitute expert ‘should have the

opportunity to express his opinions in his own language after reviewing the evidence
and performing whatever tests prior experts on both sides were allowed to perform,’”

48 Shipp, 2019 WL 4040597, at *2 (quoting Lincoln Nat’l Life Ins. Co. v. Transamerica Fin. Life
Ins. Co., No. 1:04-CV-396, 2010 WL 3892860, at *2 (N.D. Ind. Sept. 30, 2010)). See also
Rouviere v. Depuy Orthopaedics, Inc., No. 1:18-CV-04814, 2020 WL 6939646, at *3
(S.D.N.Y. Nov. 24, 2020) (noting that “permitting Plaintiffs to expand the scope of their expert
report to include [new] opinions . . . would constitute improper scope creep for a substitute
expert”); McDonald v. Wexford Health Sources, Inc., No. 09-CV-4196, 2016 WL 1383191, at
*7 (N.D. Ill. Apr. 7, 2016) (concluding that “courts confronted with an expert who dies before
trial have allowed a substitute expert to issue a new report that falls within the scope of the
original expert’s report, addresses the same subject matter, and utilizes the same theories of
liability in damages or expresses the original expert’s opinions in their own language provided
they address the same subject matter without meaningful change”); Baumann v. Am. Family
Mut. Ins. Co., 278 F.R.D. 614, 616 (D. Colo. 2012) (holding that substitute “opinion should
not stray from the subject matter of [the original] opinion. To the extent that [replacement
expert] covers new material in his deposition, Defendant may file a motion to exclude that
portion of [the] opinion”).
49 Shipp, 2019 WL 4040597, at *2 (quoting Potoski v. Wilkes Univ., No. 3:06-CV-2057, 2010
WL 3811973, at *8 (M.D. Pa. Sept. 22, 2010)).
as long as the new opinion is “substantively similar and” not “contrary to or
inconsistent with” the original opinion.51

Here, the substitute expert opinions in some instances go beyond the original
expert reports. For example, as to Doud’s opinion, the original expert noted only a
single propeller blade strike on the ground at the crash site52 and determined that the
plane’s engine was operating at a high RPM based upon damage to its propeller.53

In contrast, Doud examined ground damage and determined that there were two
propeller blade strikes; based on those strikes, he was able to perform a mathematical
calculation to determine the engine RPM at the moment of impact.54 That calculation

was notably absent from the original expert’s report and materially alter the basis for
the conclusion that the engine was operating at a high RPM at the moment the plane
crashed.

In contrast, analysis of other plane crashes that generated similar propeller
damage to this crash falls within “the subject matter and theories already espoused
by the former expert.”55 The prior expert opined that the damage to the propeller
here could be examined to determine the RPM at the time of impact—most notably

51 Shipp, 2019 WL 4040597, at *3 (quoting Lincoln Nat’l Life Ins., 2010 WL 3892860, at *2;
Morel v. Daimler-Chrysler Corp., 259 F.R.D. 17, 222 (D.P.R. 2009); U.S. ex rel. Agate Steel,
Inc. v. Jaynes Corp., No. 2:13-CV-01907, 2015 WL 1546717, at *2 (D. Nev. Apr. 6, 2015)).
52 Doc. 607-3 at 4. It is not clear that the expert was stating that there was definitively only one
strike mark. Indeed, another of Lycoming’s experts opined in 2010 that photographs of the
crash site showed two propeller blade strikes on the ground. Doc. 607-1 at 7.
53 Doc. 607-3 at 4-7.
54 Doc. 607-4 at 20-29.
through damage such as chordwise/rotational scoring damage to the propeller blades
and the blade fracturing and bending, along with nicks and gouges on the blade.56

Doud too opines that such damage indicates that the airplane’s engine was operating
at high RPM,57 and his analysis of the other plane crashes appears aimed only at
providing additional evidence that his theory and opinion is correct.58 Thus, it is

apparent that Doud is not expanding the prior expert’s theory or opinion, but merely
supplementing it with additional evidence, which is permissible.
With respect to Jensen, his expert report is in many ways similar to that of the
original expert report. The original expert did not view the carburetor, but did

examine pictures of the damaged carburetor and concluded that any damage to the
carburetor was likely the result of extreme heat resulting from the post-crash fire.59
He further opined that any loose screws and nuts in the carburetor were, again, likely

the result of the post-crash fire, which burned away the carburetor gaskets and
caused expansion and contraction of the carburetor metal.60 Jensen also opined that
damage to the carburetor was likely from a post-crash fire, which caused any loose
screws.61 To further buttress this theory, Jensen examined pictures of the carburetor

post-crash and opined that those pictures demonstrated that the carburetor’s lock tab

56 Doc. 607-3.
57 Doc. 607-4 at 30-33.
58 Id. at 33-40.
59 Doc. 607-1 at 6, 9-11.
60 Id. at 11.
washer “pants legs” were “in a clockwise (tight) position,” meaning that the screws
could not have become loose prior to the crash.62 Although these analyses were not

included in the original expert report, the Court concludes that Jensen did not expand
the prior expert’s theory or opinion, but again merely supplemented it with
additional evidence.

However, Jensen conducted engine testing to analyze the impact of loose
carburetor screws on an airplane engine’s performance.63 Specifically, Jensen
obtained a Cessna 172 aircraft—the same type involved in the crash—and loosened
the carburetor screws to different degrees to analyze whether the engine could still

start and operate.64 As a result of this testing, Jensen determined that loose screws
impacted the engine’s ability to start and operate at idle and low speeds, but did not
impact its operation at high power.65 This testing is markedly different from any

testing performed by the previous expert, and constitutes a new opinion that exceeds
the scope of the original opinion.
With respect to Gray’s opinion, there do not appear to be any inconsistencies
between the original opinion and Gray’s replacement opinion. While Sikkelee

contends that Birky opined that there was aviation fuel on the outside of the
carburetor,66 Birky’s report actually notes that it is not possible to determine whether

62 Id.
63 Id. at 13-14.
64 Id.
65 Id.
the lead deposits on the outside of the carburetor were the result of aviation fuel or
from lead soldering that melted in the fire.67 Gray’s opinion is not inconsistent with

this conclusion, as she simply opines that there was no “abundance of available fuel
on the outer surfaces of the carburetor such as would be expected if the carburetor
screws were loose during flight.”68 Sikkelee’s arguments with respect to Gray’s

opinion are thus without merit.
b. Whether Untimely Opinions Should be Admitted
Sikkelee argues that exclusion of any improper opinion is warranted because
of the significant prejudice that she will face should those opinions be admitted.

Sikkelee contends that she will need to have her experts prepare rebuttals—which
will take up to six months and perhaps in excess of $100,00 to complete—which is
not feasible given that trial is set to begin in early March 2021.69 Sikkelee also argues

that Lycoming has acted in bad faith, as it “had to know and yet failed to disclose
that it was recalibrating its defense and substantially altering its theories of the case.
Defendant concealed this information from the Court and from the Plaintiff in the
six months between when permission to substitute experts was granted in early

March and when the substituted experts’ disclosures were made on September 11,
2020.”70

67 Doc. 607-6 at 7-8.
68 Doc. 607-7 at 24.
69 Doc. 607 at 11-14.
Lycoming responds that no additional testing or analysis is required to
respond to the new expert opinions, since: (1) the testing done by Jenson was simply

an attempt to replicate the test upon which Sikkelee’s expert relied and, if that test
were reliable, there would be no need to repeat it; (2) Sikkelee’s expert does not
believe in the validity of Doud’s data that he used to calculate engine power and,

accordingly, there would be no apparent need to recreate that data; and (3) with
respect to Doud’s analysis of the propeller parts, Sikkelee’s expert decided that no
analysis of these parts was necessary as their condition was not indicative of the
power of the engine at the time of the crash.71 To the extent that there may be any

prejudice, Lycoming proposes allowing Sikkelee to depose their new expert
witnesses and submit rebuttal expert reports, if necessary.72 Lycoming further
contends that there will be no disruption of trial, it did not act in bad faith, and the

substitute expert opinions are critical to Lycoming’s case, since the opinions directly
rebut Sikkelee’s theories of liability.73
As explained above, there are two genuine differences between the
replacement opinions and the original expert opinions. First, Doud’s reference to

two propeller strike marks and his mathematical calculation to determine engine
RPM at the moment of impact were markedly different from anything that the

71 Doc. 620 at 17-19.
72 Id. at 20.
original expert proffered.74 Second, Jensen conducted engine testing to analyze the
impact of loose carburetor screws on an airplane engine’s performance.75 Such

testing was not conducted by the original expert, nor did that expert offer an opinion
on the impact that loose carburetor screws may have on an airplane engine’s
performance.76 Although this presents a close question, the Pennypack factors weigh

in favor of admitting both opinions.
With respect to Doud’s opinion that there were two propeller marks, under the
first Pennypack factor, this opinion could not have come as a great surprise to
Sikkelee, as two of Lycoming’s other experts opined that there were two propeller

strike marks on the ground at the crash site, with one expert offering that opinion
years prior to Doud.77 Given that Lycoming’s experts opined that there were two
propeller strikes on the ground, it likewise would not have been a significant surprise

when Doud used the strike marks to perform an RPM calculation, as the formula that
he used is well known to aircraft accident investigators and is published in the book
Aircraft Accident Investigation, which Sikkelee’s own experts often use.78
As to the second factor, given that Doud’s RPM determination is based on a

relatively straightforward mathematical calculation, Sikkelee should have little

74 Compare Doc. 607-3 at 4-7 with Doc. 607-4 at 20-29.
75 Doc. 607-2 at 13-14.
76 See Doc. 607-1.
77 Doc. 607-1 at 7; Doc. 607-2 at 8.
78 See Doc. 607-4 at 26. Sikkelee likewise relies on this book, indicating that this formula was
difficulty in curing any prejudice, as she may simply have her experts perform the
same mathematical calculation, or review the photograph upon which Doud relied

to determine the distance between the propeller strikes to attempt to refute that
distance calculation or to refute the notion that there were in fact two propeller
strikes.79 Third, in light of the lack of difficulty in curing any prejudice, and the fact

that Sikkelee would not need to expend significant time or resources countering
Doud’s opinion, permitting the opinion would not disrupt an orderly and efficient
trial in this matter.
With respect to the fourth factor, there does not appear to be any bad faith in

Doud’s or Lycoming’s actions. Lycoming obtained permission to replace its prior
expert after that expert died in 2018.80 As Lycoming rightly notes, it could not dictate
the opinion that Doud would give, or how he would reach his conclusions. These are

matters that must be left to the expert, and striking portions of the report that
improperly exceed the bounds of the original expert report is the proper remedy,
rather than expecting Lycoming to dictate to its experts what conclusions they must
reach.

Finally, the evidence proffered is of some importance. The fact that Doud is
able to use propeller strike marks to accurately determine engine RPM based upon

79 Although Sikkelee argues that she is prejudiced because any damage at the crash site no longer
exists and the image is skewed (Doc. 629 at 9), this is not the type of prejudice with which
Pennypack is concerned; Sikkelee may still make all of these arguments before a jury in an
effort to undercut Doud’s opinion.
a well-established and accurate mathematical formula is critical in helping
Lycoming establish that the airplane engine was operating at full power at the time

of the crash, which would effectively counter Sikkelee’s assertion that the engine
failed shortly after takeoff, which in turn led to the crash. This evidence would
significantly aid a jury in reaching a liability determination. Although Sikkelee

argues that the evidence is not critical because Lycoming did not believe it necessary
in 2011 when its original experts issued their reports, this argument does not hold
water. While Doud conducts a propeller damage analysis similar to the analysis
conducted by Lycoming’s original expert,81 Sikkelee and her experts go through

great lengths to discredit such an analysis; if Sikkelee believes that a propeller
damage analysis is insufficient to demonstrate that the engine was operating at high
RPM, it is—at best—disingenuous to argue that other evidence supporting
Lycoming’s theory is not important.82 Consequently, the Pennypack factors weigh

in favor of admitting Doud’s propeller RPM analysis, and Sikkelee’s motion will be
denied in that respect.
Turning to Jensen’s analysis of the impact of loose carburetor screws on

airplane engine performance, first, there again does not appear to be significant
surprise or prejudice to Sikkelee. The very same tests that Jensen conducted were
previously conducted by Sommer, one of Sikkelee’s experts.83 It could not have

81 See Doc. 607-4 at 30-33.
82 Doc. 613 at 16-17.
come as a surprise that Lycoming would seek to recreate Sommer’s test, nor is
Sikkelee prejudiced by this, given that her expert has already conducted that test and

would have all of the information needed to counter Jensen’s opinion. Second, given
that Sikkelee has already performed all necessary tests, any prejudice could be cured
simply by deposing Jensen. In light of the ease with which Sikkelee may alleviate

any prejudice, allowing Jensen’s opinion would not disrupt trial, regardless of the
imminence of trial.
Fourth, for the reasons discussed above with respect to Doud, there does not
appear to be any bad faith in Jensen’s new testing and opinion. Finally, the new

opinion appears to be important to the defense. With respect to Jensen’s lock tab
washer analysis, this analysis indicates that the carburetor screws were not loose at
impact, which directly refutes Sikkelee’s claims that loose carburetor screws caused

the crash. Similarly, Jensen’s tests on engine performance with loosened carburetor
screws directly contradicts Sikkelee’s theory of the case and undermines her experts,
making it important to Lycoming’s defense. Accordingly, the Pennypack factors also
weigh against exclusion of this opinion, and Sikkelee’s motion to strike will be

denied in its entirety.
ii. Motion to Strike Michael Dreikorn
Sikkelee has also filed a motion to strike the “untimely disclosed expert”

opinion of Michael Dreikorn.84 Sikkelee argues that this report should be excluded
because the report is untimely, there is no justification for the untimely disclosure,
and said untimely disclosure is prejudicial to her.85 Sikkelee argues that expert

reports were due in November 2011, and that Lycoming did not disclose that it would
submit any report from a regulatory expert.86 Sikkelee served the expert report of
Michael Schiefer (a substitute expert) on September 4, 2020 and, on October 2, 2020,
Lycoming served Dreikorn’s report, which it argues is a rebuttal to Schiefer’s

report.87
Lycoming responds that the Court’s April 27, 2020 Order did not expressly
prohibit Lycoming from filing rebuttal reports to Sikkelee’s substitute experts.

Therefore, Lycoming argues, its rebuttal report was timely under Fed. R. Civ. P.
26(a)(2)(D)(ii), as it was served within thirty days of Sikkelee’s substitute report.88
Even if the report were deemed untimely, Lycoming asserts that exclusion is
unwarranted because there is no prejudice to Sikkelee, and Dreikorn’s opinion is

important to Lycoming’s defense.89

84 Doc. 648.
85 Doc. 649.
86 Id. at 3.
87 Id. at 4.
88 Doc. 661 at 4-11.
The Court concludes that Dreikorn’s report is a permissible rebuttal opinion,
as Schiefer’s report presents some new arguments and analysis, and Dreikorn’s

report appears aimed at countering those new arguments. However, even assuming
that the rebuttal report is untimely, the Court concludes that the Pennypack factors
weigh in favor of admission.

First, there does not appear to be any prejudice to Sikkelee; although Sikkelee
asserts that Lycoming’s untimely disclosure deprived her of the ability to file a
Daubert challenge, she waited two months after receiving the Dreikorn report to file
this motion when, instead, she could have filed a Daubert motion in time to hear any

arguments related to the Dreikorn report at the Daubert hearing held on January 19,
2021. Moreover, Sikkelee has sufficient time to prepare for cross examination, and
Lycoming has offered Dreikorn for deposition.90

Admitting Dreikorn’s opinion also would not disrupt the order or efficiency
of trial. Plaintiff has no right to rebut this rebuttal expert, and there is sufficient time
to depose the witness and prepare to cross-examine Dreikorn at trial. Moreover, there
does not appear to have been bad faith or willful non-compliance with a court order,

as Lycoming filed a rebuttal report to respond to new opinions that were recently
offered by Sikkelee’s replacement expert. Finally, this testimony is of some
importance, as it is the only expert opinion that rebuts Schiefer’s opinion, and

Dreikorn’s opinion is therefore necessary to counter Schiefer’s opinion. In sum,
Dreikorn’s opinion is a legitimate rebuttal opinion but, even if it were untimely, the

Pennypack factors weigh in favor of admitting said opinion, and Sikkelee’s motion
will be denied.
iii. Motion to Strike Donald Sommer and Richard McSwain

Finally, Lycoming seeks to exclude as untimely the opinions of Sommer and
McSwain.91 Lycoming contends that, in its motion to strike Sommer and McSwain’s
expert reports, it referenced numerous analytical gaps and issues in said reports and,
in response, both experts submitted supplemental reports on October 9, 2020 that

contained new opinions in an attempt to shore up the deficiencies that Lycoming had
cited.92
For the first time, McSwain opines that an examination of a sectioned portion

of one of the fastener holes (identified as fastener hole number one) shows shearing
of the first six threads in the bowl fastener hole but no evidence of shearing on the
seventh thread. McSwain concludes that the lack of thread engagement on the
seventh thread proves that the screw must have been at least six flats loose prior to

the crash. He further opines that similar features are present on fastener hole number
four and “that ‘axial cyclic thread rubbing marks’ in the throttle body fastener holes
numbers 2 and 3 are evidence that they were more likely than not also out one full

91 Docs. 627, 628.
rotation because they also exhibited throttle body fastener hole thread contact
markings.” 93 Sommer reaches the same opinion in his supplemental report.

McSwain further opines that already-loosened carburetor screws can rotate three
flats in one second, which would permit the aircraft engine to start, but then fail
immediately after takeoff.94

Lycoming asserts that, under the Pennypack factors, the experts’ belated
opinions were a willful violation of the Court’s scheduling Order, as the opinions
were offered well after the respective deadlines for expert reports, and only five
months prior to trial.95 Sikkelee responds that the new opinions were issued to rebut

the opinion offered by Lycoming’s replacement expert, Jensen, who opined that
there was damage to the carburetor screw threads down to the 6-7 thread, which
would indicate that the carburetor screws were fully engaged and further opined that

the fact that the engine started is conclusive proof that the carburetor screws were
not loose.96 Even if the opinions were new, Sikkelee contends that they would be
admissible under the Pennypack factors.97
As to McSwain and Sommer’s screw thread analysis, the admissibility of that

portion of the rebuttal opinion is complicated by Lycoming’s decision at the Daubert
hearing to withdraw Jensen’s screw thread analysis. Lycoming’s decision to

93 Doc. 628-8 at 3; see id. at 2-8.
94 Doc. 637-2 at 2-3.
95 Id. at 10-11.
96 Doc. 637 at 7-16.
withdraw Jensen’s screw thread analysis means that McSwain and Sommer’s screw
thread analysis can no longer be deemed a rebuttal opinion, as there is no longer an

opinion for them to rebut—at least as to the screw thread damage analysis. This
portion is thus an untimely opinion that must be analyzed under Pennypack. An
examination of those factors reveals that McSwain and Sommer’s thread damage

analysis should not be excluded.
First, as to the prejudice or surprise, given that Lycoming’s own expert first
introduced the theory that damage to the carburetor screw threads indicates that the
screws were fully engaged at the time of the crash, it should not be surprising that

Sikkelee would seek to respond to this assertion. However, there is discernable
prejudice in light of Lycoming’s decision to withdraw Jensen’s screw thread damage
analysis. Were Sikkelee permitted to offer McSwain and Sommer’s screw thread

analysis with Jensen’s opinion having been withdrawn, it would leave McSwain and
Sommer’s screw thread analysis unrebutted and, essentially, unrebuttable. This
rather significant prejudice weighs in favor of excluding McSwain’s screw thread
analysis. Nevertheless, under the second factor, any prejudice could be mitigated by

permitting Jensen to offer his opinion at trial, which would permit Lycoming to
attempt to counter McSwain’s opinion.
With regard to the third Pennypack factor, admitting the screw thread analysis

would likely not disrupt trial, as Jensen has already prepared an opinion that could
rebut McSwain and Sommer’s screw thread analysis, and any necessary depositions
could be conducted prior to trial. Fourth, there does not appear to be any bad faith
or willfulness in the actions of Sikkelee’s experts, given that they responded to a

new opinion that was just recently offered by Jensen, even if that opinion has now
been withdrawn.
As to the final Pennypack factor, any importance that McSwain and Sommer’s

screw thread analysis once held as a rebuttal opinion evaporated when Lycoming
withdrew Jensen’s screw thread damage opinion. However, as explained below, this
portion of McSwain’s opinion is critical in detailing how he and Sommer may opine
with any degree of certainty that the carburetor screws were loosened to a sufficient

degree that the aircraft’s engine could have failed. This Pennypack factor therefore
weighs heavily in favor of admission, and the relative weight of the Pennypack
factors militate slightly in favor of permitting McSwain and Sommer’s screw thread

analysis. As a necessary corollary, however, Lycoming will be permitted to
reconsider its withdrawal of Jensen’s screw thread analysis, and Jensen will be
permitted to offer that opinion at trial.98
Similarly, the Court concludes that McSwain and Sommer’s opinion that

screws may loosen by three flats within one second due to vibration—meaning that
an aircraft engine may start but then fail shortly after takeoff—is admissible under
the Pennypack factors. With respect to surprise or prejudice, there is likely little

98 Or, in contrast, Sikkelee will be permitted to withdraw this portion of McSwain and Sommer’s
rebuttal opinion. Should she choose to withdraw that portion of the rebuttal opinion, Jensen’s
surprise, as Lycoming itself asserts that it is not possible, based on McSwain’s
testing, for an engine to start when carburetor screws are loosened six flats, which is

the approximate looseness needed before an engine will fail. It is only natural that
Sikkelee would seek to counter this assertion.
There is, however, some possibility of prejudice. Lycoming will need to

respond to McSwain’s testing, which will take some time and effort. Additionally,
Lycoming will need to question McSwain about his testing methodology, amongst
other things. However, this prejudice may be largely alleviated by requiring Sikkelee
to submit McSwain (and, to the extent necessary, Sommer) for a deposition as soon

as is practically possible. This would permit Lycoming to have any questions
answered and, if the deposition is conducted in the immediate future, would permit
Lycoming to conduct its own tests to confirm or refute McSwain’s tests. This should

permit Lycoming to cure any prejudice that it may experience. As to the third
Pennypack factor, although trial is rapidly approaching, Lycoming should be able to
depose McSwain and conduct its own testing before trial, meaning that orderly and
efficient trial will not be disrupted.

Fourth, it is again difficult to discern any bad faith or willfulness in the actions
of Sikkelee’s experts, as they were largely done in response to Jensen’s recently
proffered expert report. As to the final and most important Pennypack factor, the

importance of the evidence, the evidence here is critical to Sikkelee’s case.
McSwain’s testing—demonstrating that an engine will shut down when
carburetor screws are loosened by six flats but, simultaneously, will not start when

the screws are loosened four or more flats—gives rise to a natural question that
Lycoming’s experts have exploited: if loose carburetor screws caused Mr. Sikkelee’s
aircraft to lose power and crash, how was he able to start the aircraft in the first

instance? McSwain’s recent testing and opinion demonstrates that it is possible for
the engine to start, but then loosen to a sufficient degree during takeoff that the
engine would then fail shortly after takeoff. Such evidence is critical for Sikkelee
and, absent this evidence, it is difficult to conceive of how a jury could find in her

favor at trial. This factor thus strongly weighs in favor of admitting McSwain and
Sommer’s opinion regarding screw loosening and, after weighing all Pennypack
factors, the Court concludes that this portion of McSwain and Sommer’s rebuttal

opinion is therefore admissible.
B. Motions to Strike on Substantive Grounds
Both Sikkelee and Lycoming have also filed motions to exclude certain expert
opinions on substantive grounds, arguing that the expert opinions are inadmissible

under Daubert and its progeny. Sikkelee seeks to exclude portions of the expert
opinions proffered by Tom Eagar, Dale Alexander, Leslie Doud, Randy Jensen, and
W. Jeffrey Edwards.99 Lycoming in turn seeks to exclude all or portions of Michael
Schiefer and Donald E. Sommer’s opinions.100

i. Sikkelee’s Motion to Strike Tom Eagar’s Opinion
First, Sikkelee seeks to exclude Tom Eagar’s opinion.101 Eagar is Lycoming’s
expert witness who specializes in welding and metallurgy, but who Sikkelee alleges
has no expertise in aircraft accident investigation or fire origin methodology.102

Sikkelee contends that, nevertheless, Eagar’s expert report addresses aircraft
accident investigation methodology—which is outside of his area of expertise—and
offers “unscientific commentary” regarding the relevance of certain documents and

the credibility the Sikkelee’s experts.103
Sikkelee asserts that, despite having no expertise in aviation or aviation
accident methodology, Eagar reviews numerous standards and guides on aviation

accident methodology and opines that Sikkelee’s experts fail to adhere to those
standards, and critiques Sikkelee’s expert opinion on bases other than metallurgy or
welding—he instead bases his critique on examination of logical fallacies that they
allegedly committed.104

99 Docs. 608, 610, 612, 614.
100 Docs. 616, 618.
101 Docs. 608, 609.
102 Doc. 609 at 1.
103 Id. at 1-2.
Sikkelee argues that Eagar is not qualified to offer an opinion regarding
aviation accident investigation, as he has no specialized training or expertise in that

field.105 She further argues that Eagar’s critiques of the methodology of Sikkelee’s
experts are unreliable, as they are not based on any sound scientific techniques or
theories but, rather, are based on his lay interpretation of accident guides and
standards.106 Finally, Sikkelee asserts that Eagar’s opinion fails the “fit” prong of the

Daubert analysis, as his “subjective views about methodology and logic are not
founded in objective, reliable, scientific knowledge.”107
Lycoming in turn argues that Eagar “is preeminent in the field of engineering,

with expertise in fire science, metallurgy, and materials processing and
manufacturing[, and,] [a]s a consultant, he has participated in numerous aircraft
accident investigations and has also provided his expertise to assist aerospace
manufacturers and related businesses.”108 Eagar used this experience to “inspect[]

the subject carburetor and conduct[] temperature testing on an exemplar carburetor
to simulate the effects of the post-crash fire” after which he concluded “that the
evidence does not support Plaintiff’s experts’ opinions.”109 Lycoming asserts that

Eagar then “applied the scientific method and reliable accident investigation
methodologies to identify the logical fallacies and errors that permitted Plaintiff’s

105 Id. at 9-11.
106 Id. at 11-14.
107 Id. at 14-15.
108 Doc. 623 at 4; see id. at 5-6, 12-14.
experts to arrive at their erroneous conclusions.”110 Thus, Lycoming argues that
Eagar is qualified to offer an expert opinion, and his opinion is reliable.111 Lycoming

further contends that Eagar’s “identification of the egregious flaws in Plaintiffs’
expert’s methodologies and opinions will assist the trier of fact in evaluating the
validity of the Plaintiff’s opinions in this complex products liability case.”112

Given the liberal qualification standards,113 the Court concludes that Eagar is
sufficiently qualified to offer his expert opinions. Eagar conducted a number of tests
on carburetors and metal to determine whether heat or vibration could cause the
damage to the screws that was noted by Sikkelee’s experts.114 This is well within

Eagar’s area of expertise given that he is, among other things, a professor of
materials engineering at the Massachusetts Institute of Technology (MIT) and has
degrees in metallurgy from MIT.115

Although Sikkelee contends that Eagar is unqualified to offer an opinion on
aircraft accident investigation or offer critiques of Sikkelee’s expert opinions in that
area,116 the Court finds that Eagar is likewise qualified to offer an expert opinion in
those areas. At the Daubert hearing Eagar explained that he has investigated over

110 Id.; see id. at 14-19.
111 Id. at 12-19.
112 Id. at 4-5.
113 See Betterbox Commc’ns Ltd. v. BB Techs., Inc., 300 F.3d 325, 328 (3d Cir. 2002) (noting that
the Third Circuit “interpret[s] the specialized knowledge requirement liberally” (internal
quotation marks omitted)).
114 Doc. 607-1.
115 Doc. 607-2.
fifty aviation accidents—including more than one dozen failure analysis
investigations for Cape Air—and frequently offers opinions regarding the causes of

crashes.117 Eagar further testified that he learned accident investigation techniques
and methodologies through decades of on-the-job experience where he frequently
relied on treatises and other authoritative documents to perform his job.

Although it is true, as Sikkelee notes, that Eagar does not appear to have any
formal education or training in the area of aircraft accident investigations, the Third
Circuit has repeatedly affirmed that the “basis of [an expert’s] specialized
knowledge can be practical experience as well as academic training and

credentials.”118 This training must provide an expert with “skill or knowledge greater
than the average layman.”119 Eagar’s decades of experience in aircraft accident
investigations and frequent reliance on authoritative texts in that field of work are
more than sufficient to qualify him as an expert in that area.120

117 See also Doc. 623-1 at 4.
118 Betterbox, 300 F.3d at 327.
119 Id. at 328.
120 Cf. United States v. Burton, 404 F. App’x 617, 623 (3d Cir. 2010) (noting that two decades of
experience as a narcotics officer qualified an individual “to testify as an expert on narcotics”);
United States v. Nelson, 372 F. App’x 289, 293 (3d Cir. 2010) (holding that agent was qualified
to offer opinion as he “was a DEA agent with over 15 years experience . . . [and] was trained
for 14 weeks at Quantico and had been involved in hundreds of drug operations, . . .
approximately 10%-20% of [which] involved cooking crack cocaine in a microwave”); Krys
v. Aaron, 112 F. Supp. 3d 181, 204-05 (D.N.J. 2015) (expert qualified to offer opinion because,
although he “lacks any formal academic training in an area relevant to the securities area, he
does have decades of experience advising and consulting on ‘capital market issues concerning
trading, risk management, operations, and technology’ across ‘global capital markets
Sikkelee next asserts that Eagar’s opinion is unreliable, as he is unqualified to
offer an opinion as to aircraft accident investigations, and his assertions regarding

the flaws in Sikkelee’s expert’s opinions are incapable of testing.121 The Court
disagrees. As detailed above, Eagar examined the damaged carburetor and
conducted tests to determine whether the damage observed is consistent with
Sikkelee’s theory that the carburetor screws were loose before the crash.122 Eagar

then examined Sikkelee’s experts’ reports to determine whether those experts made
logical mistakes in reaching their conclusions. Eagar has developed his skills in
analyzing logical fallacies through more than 25 years of experience teaching at

MIT, and both cited to, and relied upon, scientific literature that discusses logical
fallacies in rendering his opinions.123 Thus, not only is Eagar qualified to discuss
logical fallacies, but his opinions and methodology are easily reviewable and testable

such that Sikkelee may attempt to rebut his opinions.
Finally, although Eagar undoubtedly does not have expertise within all of the
subject areas where he opines that Sikkelee’s experts committed logical fallacies,
that is not relevant to the question of whether his opinions are reliable. Eagar offered

opinions on the logical fallacies that Sikkelee’s experts allegedly committed—to
offer such an opinion, Eagar does not need to specialize in those areas, but merely
needs specialization in the field of logical fallacies. The application of logic and

121 Doc. 609 at 11-14.
122 Doc. 609-1.
examination of logical fallacies does not necessarily depend on a deep understanding
of the underlying subject matter, as one may examine whether a conclusion is logical

without examining whether a conclusion is correct.124
This is precisely what Eagar did here. For example, on page three of his report,
Eagar opined that Sikkelee’s experts failed to consider and rule out causes for the
crash other than carburetor failure.125 Eagar notes that, under the scientific method,

an expert must eliminate other potential causes of a crash before reaching a definitive
conclusion as to the cause of the crash.126 Rather, Eagar contends, Sikkelee’s expert
engaged in a highly flawed reverse scientific process, whereby they drew a

conclusion first, then discarded all evidence to the contrary.127 Eagar similarly
concludes that, if Sikkelee’s experts considered other potential explanations but
simply did not discuss them in their reports, they committed a bifurcation fallacy.128

Eagar also alleges that Sikkelee’s expert makes numerous “unsupported, conclusory
statements” that damage the integrity of that expert report.129 Although Eagar may
not have the expertise to criticize the correctness of some of Sommer’s conclusions,
he is qualified to criticize analytical and logical gaps in Sommer’s opinion.

124 For example, it is logically incorrect to say that “if some A’s are B’s, and some B’s are C’s,
then some A’s must be C’s.” That does not mean, however, that the statement is factually
wrong, as it is possible that some A’s are in fact C’s (and also possible that no A’s are C’s).
One does not need any understanding of A’s, B’s, or C’s to critique the logic of the statement.
125 Id. at 4-6.
126 Id.
127 Id.
128 Id. at 4-5.
Because logical fallacies and the scientific method are well-accepted and
understood by experts, Eagar may rely upon those techniques in his opinion.

Moreover, because Eagar has “good grounds for his . . . belief” that Sommer
committed logical fallacies and failed to follow the scientific method, his opinion is
sufficiently reliable.130 Whether Eagar is ultimately correct, or whether his opinions

are entitled to any substantial weight, is a matter for a jury to decide.
Finally, Sikkelee argues that Eagar’s opinions do not fit this case, as they are
not relevant to what caused the plane crash, and “do not establish that the Plaintiff’s
experts failed to follow appropriate aviation accident investigation methodology.”131

The Court concludes that Eagar’s opinions do fit the case. There is certainly some
connection between the existence of logical fallacies and the failure to follow proper
scientific method and the weight that should be afforded to an expert opinion.

Eagar’s critiques of Sommer’s opinion would be helpful to a jury in assigning weight
to Sommer’s opinion, and is therefore admissible.
ii. Sikkelee’s Motion to Strike Dale Alexander’s Opinion
Turning next to Sikkelee’s motion to exclude expert testimony from Dale

Alexander, Sikkelee contends that Alexander is not sufficiently qualified to offer
certain opinions, as he was retained to perform metallurgical, materials failure, and
aircraft accident investigation evaluations despite the fact that, as a nuclear engineer,

130 Elcock v. Kmart Corp., 233 F.3d 734, 745 (3d Cir. 2000) (internal quotation marks omitted).
he has no specialized knowledge in these areas nor any specialized training or
experience in aircraft accidents or metallurgy.132 Sikkelee further argues that

Alexander’s opinion “that the metallurgical features of the screw threads in the
subject carburetor were caused by thermal expansion and cooling and not metallic
transfer from vibration” is wholly speculative, as Alexander simply assumes that,

because heating may cause expansion and cooling may cause contraction, this is
what actually happened to the carburetor screws.133
Lycoming responds that Alexander is well-qualified in the areas of materials
science and metallurgical failure analysis, with more than 30 years of experience in

research and failure analysis with expertise focused in the field of materials science
and metallurgy.134 He has also led more than 100 projects that involved aviation and
has been invited to speak at the General Aviation Air Safety Investigators workshop,
among other qualifications and honors.135

Lycoming also contends that Alexander reliably applied his expertise to this
case.136 For example, Alexander applied his expertise in materials failure analysis
and metallurgy to analyze the effects of the post-crash fire on the carburetor.”137 In

two other sections, Alexander “examined and tested exemplar carburetors and

132 Doc. 611 at 3-7, 10-13.
133 Id. at 13-15.
134 Doc. 624 at 7-9, 14-18.
135 Id.
136 Id. at 20-22.
applied his engineering experience and tribological knowledge to confirm that
during the installation of a fastener and washer, there is rotational wearing contact

under load that can transfer a microscopic amount of the washer plating.”138
Alexander also reviewed the positions of the lock tab washers in post-accident
photographs and observed that they were in their full clockwise ‘tight’ position” and

then “tested an exemplar carburetor by assembling it with the proper installation
torque and then performed a same perspective comparison view with the subject
carburetor.”139 In yet another opinion, “Alexander employed his expertise in
metallurgy and materials science to identify multiple sources of the lead detected on

the exterior of the subject carburetor,” while “Alexander visually examined the
subject carburetor and used SEM/EDS analysis to sample materials from an
exemplar carburetor . . . [and] confirmed the lead plug in the carburetor bowl melted

away during the post-crash fire and accounts for the presence of lead on the exterior
of the subject carburetor.”140
The Court concludes that Alexander is qualified to offer opinions in materials
science and metallurgical failure analysis. Alexander has directed the Materials

Practice division of Engineering Systems Inc. since 2009 and, in that capacity, has
managed numerous materials engineering personnel and materials analysis

138 Id.
139 Id. at 20-21.
laboratory facilities.141 He has also worked as the lead investigator in more than 300
projects—over 100 of which were aviation-related—where he used a number of

accepted methods and techniques to conduct materials failure analyses.142 Finally,
although Alexander’s training and education focused primarily on nuclear
engineering, he concentrated his studies on the impact of radiation on materials and,

as Alexander explained at the Daubert hearing, to understand how radiation impacts
materials, one must have a deep understanding of the materials themselves. This
education and experience is sufficient to qualify Alexander as an expert in the fields
of materials science and metallurgical failure analysis.

Lastly, Sikkelee argues that Alexander’s opinion is unreliable insofar as he
opines that thermal heating and cooling caused the damage to the carburetor screw
threads—without performing testing, referring to any authoritative texts, or
examining heat-damaged carburetors to support his conclusion.143 However, the

Court finds that the opinion is sufficiently supported and any questions as to the
accuracy of the opinion—or whether it would have been best for Alexander to
conduct certain tests—goes to weight, rather than admissibility.

Alexander (and Novak) examined the carburetor and determined that the
carburetor’s gasket had been burned off during the post-crash fire.144 Based on

141 Doc. 624-1 at 3.
142 Id. at 3-4.
143 Doc. 611 at 14-15.
“[b]asic engineering principles,” Alexander determined that the loss of the gasket
resulted in the looseness between the carburetor bowl and throttle body that was

observed post-crash. 145 Alexander also opined that accident site photographs
depicted the aircraft engine resting on the carburetor, which allowed the steel
fastener threads to imprint onto the bores of the through holes of the throttle body
aluminum, which was softened by the post-crash fire.146 This opinion is supported

by literature confirming the melting and softening temperatures of steel and
aluminum, and the melting of other materials in the engine.147
Alexander also conducted cross-sectional metallography and determined that

there was “inter-dendritic separation of the carburetor bowl Aluminum alloy
threads.”148 He compared the damage to the carburetor with an exemplar carburetor
that had been subjected to vibration; a microscopic examination of the exemplar

carburetor revealed “that the subject carburetor throttle body through hole marks are
different and distinct from vibration induced marks and therefore were not caused
by pre-accident carburetor joint looseness.”149 This testing and analysis is sufficient
to render Alexander’s opinion reliable. While Alexander may (or may not) be wrong

in his conclusions, his opinion is sufficiently supported by the facts and evidence

145 Id.
146 Doc. 624-1 at 10-11; Doc. 624-3 at 14.
147 Id.
148 Doc. 624-1 at 10-11.
that it should be presented to a jury. Sikkelee’s motion to strike Alexander’s opinion
will therefore be denied.150

iii. Sikkelee’s Motion to Strike Propeller Analysis and RPM
Calculation from W. Jeffrey Edwards, Leslie Doud, and
Randy Jensen

Next, Sikkelee argues that Edwards, Doud, and Jensen’s propeller analysis
and calculation of the engine propeller’s revolutions per minute (RPM) should be
excluded for three reasons.151 First, she contends that a simple visual inspection of
the propeller blades cannot be used to determine the engine’s power output when the
airplane crashed, and the analysis used by the experts contradicts the circumstances
and methodology needed to reach such an opinion. Specifically, some literature that
addresses the calculation of RPM based upon propeller damage after a crash cautions
that such analysis is only reliable is the impact angle was less than 5 degree; blades

that are bent in their midsection do not indicate high or low RPM; and, if only one
blade is bent, the bend was caused by something other than propeller rotation.
According to Sikkelee, the experts nevertheless concluded here that, despite an

150 Sikkelee initially argued that Alexander and Novak’s opinions were not sufficiently delineated
in their report and, accordingly, they must submit separate reports that outline their individual
contributions to the report. (Doc. 630 at 2-3). Counsel clarified at the Daubert hearing that
subsequent disclosures from Lycoming adequately delineated which expert contributed to
which portions of their report. The Court therefore denies as moot Sikkelee’s request that
Alexander and Novak submit separate reports.
impact angle of greater than 20 degrees, the engine was operating at a high RPM
because one propeller was bent in its midsection.152

Second, Sikkelee contends that the experts conclude that a National Safety
Transportation Board (NTSB) photograph of the crash site depicts two propeller
strike marks on the ground, but that is contradicted by multiple investigators who

concluded that there was only one strike mark on the ground. These investigators,
who came from the NTSB, the Cessna Aircraft Company, and Lycoming, all
appeared at the crash site and confirmed that there was only one propeller strike
mark, as did Lycoming’s prior expert witness. Lycoming’s experts here concluded

that the gouge was a strike mark without conducting any analysis of the mark, such
as reviewing depth, contours, or paint transfer, meaning that the gouge could have
been in existence prior to the crash or have been caused by a different plane part.

Because the experts undertook no underlying analysis, a review of their conclusion
is impossible, rendering their opinion unreliable.153
Third, Sikkelee asserts that, while there is a mathematical formula to calculate
preimpact engine RPM if there are at least two propeller ground strikes and if the

distance between the propeller ground strikes can be accurately measured, the single
NTSB photograph of the crash site does not establish two strike marks, nor does it
permit any precise distance measurements that would permit an accurate calculation.

152 Id. at 7-10, 16-17.
Moreover, the experts do not know the type of camera, the lens used, or the distance
or angle from which the photograph was taken, all of which render speculative any

determination of the distance between the strike marks. Because precise
measurements are required to perform an RPM calculation—even a
mismeasurement of as little as one inch will alter the calculation—Sikkelee argues
that the opinion is inherently unreliable.154

Lycoming in turn asserts that its expert’s calculation was performed in
accordance with authoritative sources on the subject of determining RPMs through
propeller damage—using techniques that have been adopted by the NTSB—and note

that the propeller here exhibits at least eight of the thirteen damage signatures that
are indicative of high power and high RPM impacts.155
As to whether there were two propeller strike marks on the ground, Lycoming

contends that, not only did the crash site examiners not conclusively determine that
there was only one strike mark, but the photograph demonstrates two gouges and
“[t]he propeller blade that struck first, Blade no. 1, hit the pavement with such force
it broke off the outer 17 to 18 inches of the propeller. The other half of the propeller,

Blade 2, shows unmistakable evidence of ground contact that can only be explained
by a second blade strike.”156

154 Id. at 11-12, 19-21.
155 Doc. 625 at 14-17.
Finally, Lycoming asserts that Doud was able to able to measure the distance
between the strike marks using photo scaling, which he was able to do because he

knew the size of a piece of paper in the photograph. To the extent that Sikkelee
believes that Doud speculates as to the size of the paper in the photograph, Lycoming
asserts that this is a factual issue reserved for the jury—because Doud based his
calculation on a reliable methodology, his opinion should be submitted to the jury.157

After reviewing the evidence, the Court finds Sikkelee’s arguments
unpersuasive. First, with respect to her argument that the experts’ RPM calculation
based on propeller damage is fatally flawed, the Court disagrees. Doud relied on

numerous characteristics that he determined were indicative of high engine power,
including: chordwise/rotational scoring on the camber and face sides of the blade;
numerous blade strikes, blade twisting and fracturing, s-bending, forward bending,

rearward bending, portions of the blade having been torn off; an absence of
torsional/spiral scoring on the spinner dome surface; and material deformation of the
propeller extension/spacer opposite of the propeller blade rotation.158
Many of these indicators of high engine power are discussed in the McCreary

white paper, upon which Doud often relies in conducting his investigations.159 Doud
testified at the Daubert hearing that the indicators discussed in the McCreary white
paper are authoritative, he frequently relies on those indicators and teaches them in

157 Id. at 18-20.
158 Doc. 613-4 at 8-19.
the propeller systems and accident investigation segment of the accident
investigation course that he teaches for the Transportation Safety Institute, and that

these indicators are accepted and used by the NTSB in its accident investigations.
This is all strong evidence that the indicators upon which Doud relied are
appropriate, and his opinion in that respect is reliable.

Although Sikkelee contends that Doud’s methods and conclusions are
contrary to the information contained in Wood and Sweginnis’ authoritative book,
Aircraft Accident Investigation, which explains that propeller damage cannot
demonstrate engine RPM, that text has not been updated for more than fourteen

years160 and Doud opined at the Daubert hearing that, not only is the text outdated,
but data that has been made available in the intervening years conclusively
demonstrates that Wood and Sweginnis were incorrect in their assertions. Doud thus

adequately explained why he discounted Aircraft Accident Investigation and instead
relied on a different authoritative text.
As there is a sufficient basis for Doud’s opinion, Sikkelee’s arguments go to
the weight that should be afforded to Doud’s opinion, rather than the opinion’s

admissibility. This is a situation where competing texts offer competing views of
how and whether propeller damage may be used to determine engine power and

RPM; this is a dispute that must be resolved by a jury at trial, rather than by this
Court prior thereto.161

As to the opinion that there were propeller strike marks on the ground,
Sikkelee relies solely on the fact that the NTSB and several other investigative
bodies that investigated the crash at the time determined that there was a single
propeller strike mark.162 Regardless of whether other investigators concluded that

there was only one strike mark, two of Lycoming’s expert have determined based
upon review of accident scene photographs that there were two propeller strike
marks on the ground, and the photograph does reveal two distinct gouge marks—of

similar appearance—that are located near each other.163 Moreover, Doud explained
that he reached his conclusion that there were two propeller strike marks “with a
high degree of scientific certainty” based upon two facts.164 First, he opined that “the

photographic evidence is beyond dispute,” as it “depicts two parallel slices oriented
perpendicular to the direction of impact. The strike marks match in size and
orientation with the propeller blades.”165 Second, as Doud confirmed during the

161 See United States v. 14.38 Acres of Land, More or Less Situated in Leflore Cty., State of Miss.,
80 F.3d 1074, 1077 (5th Cir. 1996) (“As a general rule, questions relating to the bases and
sources of an expert’s opinion affect the weight to be assigned that opinion rather than its
admissibility and should be left for the jury’s consideration” (internal quotation marks
omitted)).
162 Doc. 613 at 10-11.
163 See Doc. 625 at 6.
164 Doc. 625-3 at 6.
Daubert hearing, “the damage to the tip of Blade 2, which is the non-fractured blade,
could not have occurred other than as a result of a [second propeller] blade strike.”166

Given that there is substantial evidence to support Doud’s conclusion that
there are two strike marks, the Court concludes that Sikkelee’s arguments go to the
weight that should be afforded to Doud’s opinion, rather than its admissibility.

Again, while Doud may ultimately be incorrect, this is a matter that must be left for
a jury to evaluate.
Finally, with respect to Sikkelee’s challenge to the engine RPM calculation
based on the propeller strike marks, Sikkelee asserts that it is impossible to

accurately determine the distance between the alleged strike marks, given the lack
of any reliable distance indicators in the photo upon which Doud relies.167 She
further argues that, because Doud did not account for potential lens distortions, his
calculation cannot be considered reliable.168

The Court finds both arguments weighty, but ultimately unpersuasive. As to
Doud’s measurements, he testified at the Daubert hearing that he was able to
determine upon visual inspection that, in the picture of the crash scene, there was an

8 ½ by 11-inch piece of paper in the photograph that had been folded in half.169

166 Doc. 625-3 at 6.
167 Doc. 613 at 11-15, 19-21.
168 Id.
169 As Doud discussed at the Daubert hearing, his determination of the size of the paper is
supported by his comparison of that paper to the hat contained in the photograph. See also Doc.
613-4 at 26 (noting that Doud’s determination that paper was folded paper was reasonable
Using that measurement as a baseline, Doud was able to calculate the distance
between the two strike marks in that photograph.170 Although Sikkelee may attempt

to undercut that conclusion at trial, at the moment there is no evidence in the record
that undermines Doud’s conclusion. The Court is mindful that “‘questions regarding
the factual underpinnings of the expert witness’ opinion affect the weight and
credibility’ of the witness’ assessment, ‘not its admissibility.’”171 Given that there is

some basis to support Doud’s measurements, his reliance on the piece of paper in
the photograph to conduct those measurements does not render his opinion
inadmissible.

Similarly, although Sikkelee argues that Doud’s RPM calculation is fatally
flawed because he did not account for lens distortion when determining the distance
between the propeller strikes, the Court again concludes that this issue goes to
weight, rather than admissibility. Doud scaled the photo172 using a technique that “is

widely used by accident investigators and is recognized as mathematically sound
and reliable.”173 Although, at the Daubert hearing, counsel for Sikkelee presented a
great deal of information that suggests lens and angle distortion is a real phenomenon

that can have a significant impact on distance measurements in a photograph, Doud

170 Using those measurements, Doud was able to calculate the airplane’s RPM at the moment of
impact with the ground using a well-established mathematical equation—an equation that
Sikkelee does not challenge. (Id. at 26-27).
171 Bresler v. Wilmington Tr. Co., 855 F.3d 178, 195 (4th Cir. 2017) (quoting Structural Polymer
Grp. v. Zoltek Corp., 543 F.3d 987, 997 (8th Cir. 2008) (brackets omitted)).
172 Doc. 613-4 at 26.
testified at the Daubert hearing that, in his opinion, such distortions would not
impact his measurements. There is no evidence that such distortion would have any

appreciable impact on Doud’s measurements in that particular photograph and, thus,
no direct evidence that contradicts Doud’s conclusion that such distortions need not
be accounted for in conducting measurements between objects within that

photograph.
This is not to say that Doud emerged entirely unscathed from the Daubert
hearing. Counsel for Sikkelee did some damage to Doud’s calculation by calling into
question the accuracy of his measurements. However, As the United States Court of

Appeals for the Eighth Circuit has explained:
As a general rule, the factual basis of an expert opinion goes to the
credibility of the testimony, not the admissibility, and it is up to the
opposing party to examine the factual basis for the opinion in cross-
examination. Only if the expert’s opinion is so fundamentally
unsupported that it can offer no assistance to the jury must such
testimony be excluded.174

Because there is no evidence that distortion would have a significant enough
impact to materially alter Doud’s measurement and, thus, his calculation, the
potential existence of distortions in the photograph does not render Doud’s
measurements and calculation “so fundamentally unsupported that [they] can offer
no assistance to the jury.”175 These issues therefore go to weight, not admissibility,

174 First Union Nat. Bank v. Benham, 423 F.3d 855, 862 (8th Cir. 2005).
and Sikkelee’s motion to strike the propeller damage and RPM analyses will be
denied.

iv. Sikkelee’s Motion to Strike W. Jeffrey Edwards’ Testimony
Sikkelee next seeks to exclude the expert opinion of W. Jeffrey Edwards, who
opines that, based upon certain risk factors that David Sikkelee presented and the

testimony of witnesses to the crash, Mr. Sikkelee likely induced an aerodynamic stall
that caused the plane crash.176 Sikkelee contends that Edwards provides no evidence
to support his assertion that Mr. Sikkelee made any errors or actually presented any
risk factors that could reasonably have contributed to the crash. First, Sikkelee

asserts that Edwards’ opinion about human errors is unreliable, as it is a system to
classify pilot errors and provide possible causes for a crash, but cannot aid a jury in
determining whether a crash was actually caused by human error.177

Second, Sikkelee contends that Edwards’ opinion regarding an absence of
power loss in the engine and whether pilot error caused the crash is unreliable
because he ignores eyewitness testimony that confirms the airplane’s engine “was
sputtering,” which supports the notion that engine failure caused the aerodynamic

stall and subsequent crash. In any event, the witness’ testimony cannot establish that
the stall was caused by pilot error, rather than engine failure.178 Finally, Sikkelee
argues that Edwards’ opinion in some ways does not fit the case, as his assertion that

176 Doc. 615.
177 Id. at 10-13.
a missing shoulder harness caused injuries to the passenger is irrelevant and intended
only to convince the jury that the decedent was a negligent pilot, and his discussion

of mountain flying is irrelevant since the plane did not crash near mountains.179
With the exception of one portion of Edwards’ opinion, while this presents a
close question, the Court concludes that Edwards’ opinions are admissible. Although
Edwards considered risk factors that were present when Daivd Sikkelee crashed,180

Edwards testified at the Daubert hearing that such information is important in
determining the cause of a crash and, specifically, helps frame the accident. In
reaching his opinion that pilot error likely caused the crash, Edwards relied upon

certain risk factors but, also, the absence of evidence indicating a mechanical
malfunction, accident reconstruction data, wreckage inspections, airport geography
and dimensions, and eyewitness testimony.181

While certain risk factors cannot alone support Edwards’ conclusion, such
information is still helpful in determining whether pilot error was more likely than
not the cause of the crash. For example, Edwards discusses how pilot inexperience
and decisional errors are significant contributing factors to many aircraft accidents,

and relates that to David Sikkelee by way of his inexperience flying in mountainous
terrain.182 Mr. Sikkelee’s inexperience may have led him to misperceive the risk

179 Id. at 14-15.
180 Doc. 615-1 at 47-57.
181 See Doc. 615-1.
associated with the takeoff on the day of the crash, which was extremely difficult.183
As Edwards testified during the Daubert hearing, due to the mountainous terrain

near the airport from which Mr. Sikkelee took off, were a pilot to attempt to fly
straight from the runway to clear the mountains, he would stall the aircraft; to
properly and safely take off, a pilot must instead turn from the mountains while

gaining altitude.
In addition to relying on risk factors, Edwards supports his opinion with
evidence that indicates Mr. Sikkelee did not obtain sufficient speed before takeoff,
which led to an aerodynamic stall and the subsequent crash. This evidence includes

two witnesses who stated that the aircraft was not moving fast enough for takeoff as
it moved down the runway, two witnesses who denied hearing any unusual noise
emanating from the aircraft as it moved down the runway, and a witness’ statement

that the aircraft was in a steep, nose down left turn with the left wing perpendicular
to the ground just before the plane impacted the ground.184 This information
supported, in Edwards’ opinion, the notion that pilot error caused the crash. Because
Edwards considered a great deal of information when he concluded that pilot error

likely caused the crash, his consideration of risk factors does not, alone, render his
opinion inadmissible.

183 Id.
With respect to Sikkelee’s argument that Edwards’ opinion is unreliable
because he failed to consider a witness statement from Emagene Maar that

contradicted her earlier statement—the statement upon which Edwards relied—and
which contradicts his conclusions, the Court finds that Maar’s witness statement
does not fatally undermine Edwards’ opinion.

First, Edwards apparently discounted Maar’s statement that the engine was
sputtering because that statement was made years after the accident and was
inconsistent with her statement at the time of the accident, wherein she stated only
that the aircraft engine sounded like it was operating at a low RPM.185 That earlier

statement is consistent with two other witnesses who stated that they did not hear
any unusual noises emanating from the engine during takeoff.186 Of course, Maar
later stated that the engine sounded as though it was sputtering and “was just not
going to make it.”187 While this is contradictory information, it does not render

Edwards’ opinion inadmissible, as “questions regarding the factual underpinnings
of the expert witness’ opinion affect the weight and credibility of the witness’
assessment, not its admissibility.”188 Moreover, Edwards did not rely solely on

185 Doc. 626 at 18.
186 Doc. 615-1 at 8.
187 Doc. 615-3 at 3; see Doc 626-3 at 3.
188 Bresler, 855 F.3d at 195 (brackets and internal quotation marks omitted). Similarly, at the
Daubert hearing Edwards confirmed that, while witnesses confirmed that the aircraft was
moving slowly down the runway, it was technically still possible for Mr. Sikkelee to safety
takeoff. This information likewise goes to the weight that may be afforded to Edwards’
witness statements, but also considered other factors to help rule out a mechanical
failure, such as a review of maintenance records and analysis of the aircraft

wreckage, including the propeller and ground strikes. 189 This information
collectively forms a sufficient foundation for Edwards’ opinion, such that a single,
contradictory witness statement does not render that opinion inadmissible.

Finally, Sikkelee argues that Edwards’ opinion in some ways does not fit the
case, as Edwards’ assertion that a missing shoulder harness caused injuries to the
passenger is irrelevant and intended only to convince the jury that the decedent was
a negligent pilot, and his discussion of mountain flying is irrelevant since the plane

did not crash near the mountains.190 As to Edwards’ discussion of mountain flying,
as he explained in his expert opinion, mountain flying was relevant to the crash
because flying in mountainous areas is extremely risky, particularly for novice

pilots. 191 Edwards further explained during the Daubert hearing that the
mountainous terrain near the airport from which Mr. Sikkelee took off forces pilots
to maneuver immediately upon takeoff, since attempting to fly straight after takeoff
would induce an aerodynamic stall due to the rapid rise in elevation from the

mountainous terrain. Edwards thus adequately relates the mountainous terrain to the
crash, and his opinion fits this case.

189 Doc. 615-1.
190 Doc. 615 at 15.
However, the Court finds that Edwards’ discussion of an allegedly missing
shoulder harness, and the consequences of that missing shoulder harness, are

inadmissible. First, there does not appear to be a link between the allegedly missing
shoulder harness and the crash other than, perhaps, to intimate that because Mr.
Sikkelee was negligent in failing to recognize the missing shoulder harness, he was

also negligent in the takeoff procedures; such inferences are simply not
permissible.192 Second, to the extent that Edwards opines that “[t]he facial/ head
injuries [to Mr. Sikkelee’s passenger] are consistent with [the passenger] impacting
the interior of the aircraft as a result of not wearing a shoulder harness,”193 there is

absolutely no indication in the record that Edwards has any reasonable basis to reach
such a conclusion, or that he is qualified to offer such an opinion. As a result, the
Court will exclude any testimony from Edwards related to the allegedly missing

shoulder harness and injuries that purportedly arose as a result of the missing
shoulder harness.
v. Lycoming’s Motion to Strike Michael Schiefer’s Opinion
Turning to Lycoming’s motions, Lycoming first seeks to exclude Michael

Schiefer’s expert opinion on several grounds. Schiefer opines that Lycoming was
required to report alleged issues with loose carburetor body-to-bowl screws pursuant
to 14 C.F.R. § 21.3, and concludes that, had Lycoming issued such reports, the FAA

192 The Court notes that Lycoming has not defended this portion of Edwards’ opinion in its
response brief and, thus, provides no explanation for the potential relevance of this opinion.
would more likely than not have issued an appropriate airworthiness directive under
14 C.F.R. § 39.194 He further opines that Lycoming was required to file such a report

even if the FAA was previously notified of the issue by way of an FAA Service
Difficulty Report (SDR), as the FAA does not always monitor the SDR database for
defect trends.195 He then concludes that the use of safety wire, rather than lock tab

washers, to hold the carburetor screws in place would have prevented the crash, and
that the FAA would have approved safety wire had Lycoming filed a 21.3 Report or
initiated the change itself.196
First, Lycoming asserts that its responsibilities or potential liability under 14

C.F.R. § 21.3 is not at issue in this case because Lycoming previously obtained
summary judgment on Sikkelee’s failure-to-warn claim, which was premised on an
alleged failure to comply with 14 C.F.R. § 21.3. Lycoming argues that any failure to

comply with § 21.3 is therefore simply not relevant to the remaining issues in this
case—issues of manufacturer liability and causation, as well as whether a change to
the product was substantial and whether that change was reasonably foreseeable to
Lycoming. Thus, Lycoming asserts that Schiefer’s opinion does not fit the case.197

Second, Lycoming contends that many of Schiefer’s opinions are thinly-
veiled legal conclusions that may not be presented to the jury, as they usurp the

194 Doc. 617-1 at 7-8.
195 Id.
196 Id. at 11-12.
judge’s role of instructing the jury on the law, and the jury’s role of applying the
facts to that law. For example, Schiefer opined that: Lycoming failed to submit

required reports to the FAA of failure, malfunctions, and defects in the MA-4SPA
model carburetor in violation of 14 C.F.R. § 21.3; if Lycoming had issued § 21.3
reports, the FAA likely would have issued an appropriate airworthiness directive

under 14 C.F.R. § 39; Lycoming has the final responsibility to ensure that MA-4SPA
carburetors conform to the FAA approved type design of Lycoming’s O-320 series
engines; and Lycoming is responsible for the design of all MA-4SPA carburetors,
including carburetor component parts manufactured by third parties under FAA

PMA approval.198
Third, Lycoming argues that Schiefer opinions are unreliable because they are
based solely on speculation with no factual support. Thus, Schiefer asserts that

Lycoming was required to notify the FAA of issues with the carburetors, despite the
fact that (1) there is no legal authority to support this assertion, (2) there are several
exceptions to the reporting requirement, and (3) the FAA already had all the relevant
information. Similarly, Lycoming argues, Schiefer does not cite to any authority that

supports his assertion that a report in the FAA’s SDR system puts a manufacturer on
notice of a defect or issue with its product. Schiefer also fails to support with any

legal citation his assertion that Lycoming is legally responsible for carburetor
overhaul components manufactured by third parties under FAA PMA approval.199

Finally, Lycoming argues that Schiefer has no reliable basis for his assertions
regarding the efficacy of safety wire and the cause of the accident. Despite having
no experience in engineering nor having conducted any analysis of the carburetor,

Schiefer opines that safety wire is superior to lock washers, and lock washers should
never have been used on the carburetor. He offers no analysis of what caused the
accident but, instead, merely adopts another expert’s opinion and, while he opines
that safety wire is effective, he offers no evidence that lock washers are any less

effective.200
As to Lycoming’s first argument, the Court agrees that Lycoming’s alleged
failure to comply with 14 C.F.R. § 21.3 is no longer relevant, given that judgment

has been entered on Lycoming’s behalf for Sikkelee’s failure-to-warn claim—a
claim that was premised on Lycoming’s alleged failure to comply with 14 C.F.R.
§ 21.3.201 Even though, as Sikkelee notes, Lycoming raised as an affirmative defense
that the FAA had issued a Type Certificate for the carburetor at issue here,202

199 Id. at 19-22.
200 Id. at 22-24.
201 Although Sikkelee contends that Schiefer’s opinion is necessary to elaborate upon “the
standard of care for an aviation manufacturer who has received objective evidence of a design
defect in its certificated product,” (Doc. 621-1 at 12-13), such information is not relevant, as
the Third Circuit previously held that Sikkelee cannot “use a federal duty and standard of care
as the basis for [her] state-law negligence claim.” Sikkelee, 907 F.3d at 717.
Schiefer’s opinion goes far beyond merely explaining the certification process and
FAA regulations at issue. Rather, Schiefer opines that Lycoming was legally

obligated to report carburetor issues under 14 C.F.R. § 21.3, details what that section
requires and why Lycoming was required to report under the regulations, and then
concludes that, had Lycoming issued the required report, the FAA would likely have
issued an airworthiness directive under 14 CFR § 39.203 This goes beyond simply

detailing the regulations and explaining why FAA certification does not mean that a
product is safe in order to rebut any inference or argument to the contrary from
Lycoming but, instead, reaches an impermissible legal conclusion about the

applicability of certain regulations204 and Lycoming’s legal requirements under
those regulations.205
In addition to delving into improper legal conclusions, Schiefer’s opinion

regarding Lycoming’s purported legal obligation to submit reports to the FAA is
overly speculative. As Schiefer himself notes in his expert report, companies do not
need to submit reports pursuant to 14 C.F.R. § 21.3 if any failures were the result of,

203 Doc. 617-1 at 7-9.
204 Similarly, as to Sikkelee’s contention that Schiefer’s opinion is necessary to “debunk the
Defendant’s assertion that FAA certification is an implicit declaration that a design is free of
defect” and that “that the overhaul of the subject carburetor somehow severs all responsibility,”
(Doc. 621-1 at 12-13, see id. at 11-13), his opinion goes beyond what is necessary to establish
those points, insofar as he offers opinions regarding Lycoming’s legal duties under certain
regulations.
205 See Berckeley Inv. Grp., Ltd. v. Colkitt, 455 F.3d 195, 218 (3d Cir. 2006) (permitting expert
testimony that detailed “[t]he customs and business practices in the securities industry,” but
not permitting testimony “as to whether Berckeley complied with legal duties that arose under
inter alia, improper maintenance or use.206 There is no indication in Schiefer’s report
whether he concluded that any issues with the carburetors were not attributable to

improper maintenance or use and, if so, how he so concluded. With no basis to
eliminate improper maintenance or use as a cause of the carburetor issues, his
opinion that Lycoming was required to report carburetor issues to the FAA is far too
speculative to be admitted.207

Finally, Lycoming argues that Schiefer has no reliable basis for his assertions
regarding the efficacy of safety wire and the cause of the accident. Despite having
no experience in engineering nor having conducted any analysis of the carburetor,

Schiefer opines that safety wire is superior to lock washers, and lock washers should
never have been used on the carburetor. Lycoming asserts that, while Schiefer opines
that safety wire is effective, he offers no evidence that lock washers are any less
effective.208

The Court finds this argument unpersuasive, as it goes to weight, rather than
to admissibility. Schiefer asserts that he has 43 years of experience in the aviation
field and has never witnessed a bolt secured with safety wire come loose, and notes

that the FAA considers safety wire to be the most effective method of preventing a
bolt from coming loose.209 This provides at least some basis for Schiefer’s opinion

206 Doc. 617-1 at 5.
207 This reasoning applies with equal force to Schiefer’s opinion that Lycoming controls the design
of the carburetors and, therefore, is responsible for reporting any issues to the FAA.
208 Doc. 617 at 22-24.
that safety wire is preferable to lock tab washers, even if he may ultimately be
incorrect, and even if lock tab washer may be a perfectly safe and effective method

of preventing screws from loosening.
Accordingly, Lycoming’s motion will be granted in part, such that Schiefer is
prohibited from testifying as to Lycoming’s legal duties under the regulatory
framework discussed in his expert report.210 The motion will be denied in all other

respects.
vi. Lycoming’s Motion to Strike Donald E. Sommer’s Opinion
Finally, Lycoming seeks to exclude Donald E. Sommer’s expert opinion for

three reasons.211 First, Lycoming asserts that Sommer offers no evidence that, even
if the carburetor screws were loose, they were loose enough that the engine would
have failed to obtain full power since Sommer’s own testing demonstrates that loose

carburetor screws will only impact engine power when all screws are loosened by at
least six flats. However, here Sommer conducted no testing that would permit him
to conclude that the carburetor screws were loosened by at least six flats. Moreover,
such an assertion is contrary to an NTSB photograph of the carburetor taken post-

crash, which shows two of the lock tab washers in their full clockwise orientation at
the time of impact. Lycoming contends that the absence of any evidence that would

210 Although Lycoming also challenges Schiefer’s conclusion that a report in the FAA’s SDR
system puts a manufacturer on notice of a defect or issue with its product, in this case it is clear
that Lycoming was actually informed of reports in the FAA’s SDR system, rendering this point
moot. (Doc. 617-1 at 7).
demonstrate that the screws were loosened by at least six flats fatally undermines
Sommer’s opinion.212

Second, Lycoming argues that Sommer’s own testing demonstrates that if
carburetor screws are loosened by four flats, the engine will not start,213 and the
engine will not fail until the carburetor screws are loosened by at least six flats. Thus,

if the carburetor screws were loose enough prior to the accident to have impacted
the airplane engine’s power, the engine would not have started. Lycoming asserts
that this fatally undermines Sommer’s opinion, as testimony establishes that the
engine started with no issues on the day of the accident.214

Lastly, Lycoming contends that Sommer’s opinion is unreliable because he
failed to consider, let alone rule out, the post-impact fire as the cause of any loose
carburetor screws—this demonstrates that Sommer failed to undertake a proper

differential diagnosis. Rather than use a reliable methodology to exclude fire as the
cause of the loose screws, in Lycoming’s view, Sommer simply excluded fire “by
insinuation,” despite evidence that fire caused damage to the carburetor and burned
away the gaskets against which the carburetor screws were tightened.215

212 Id. at 20-24.
213 During testing, when the carburetor screws were loosened four flats, Sommer had his assistant
use wire and physical force to press the two halves of the carburetor together to start the engine,
and then release the carburetor halves after the engine started. This effectively retightened the
screws while the engine was started.
214 Id. at 24-26.
As to Lycoming’s first argument, there is some evidence to support the notion
that the carburetor screws were loosened six flats at the time of the crash. Richard

McSwain 216 analyzed the carburetor and conducted testing on an exemplar
carburetor to determine that the carburetor bowl and throttle body were loose,
relying on evidence including that: there was lead on all sides of the carburetor,

which indicated an in-flight fuel leak resulting from loose carburetor halves, rather
than a fuel leak that started after the crash, which would have resulted in lead on
only portions of the engine; fastener hole damage in the carburetor was similar to
damage that resulted from shaker tests of a carburetor with a loose bowl, indicating

that the carburetor bowl and throttle body were loose prior to the crash;217 thread
impression marks in unthreaded portions of the fastener holes were created by
dropping weight on the exemplar carburetor, but the resulting thread marks were

different from thread marks in the actual carburetor, demonstrating that the thread
marks were not caused by the crash;218 and smooth thread contact grooves were worn
into the fastener hole walls, which was “indicative of fastener looseness and
fastener-induced thread contact wear.”219

While this collectively indicated that the carburetor screws were loose prior
to the crash, McSwain also examined the throttle body fastener holes which showed

216 Sommer’s expert opinion relies to a great extent on testing conducted by McSwain and,
accordingly, those opinions are discussed together in this section.
217 Doc. 622-12 at 17. See also McSwain’s Daubert testimony.
218 Id. at 16-17.
shearing within those holes, which indicated that the carburetor screws were loose
and were rubbing up and down inside the holes.220 As McSwain testified to at the

Daubert hearing, the throttle body fasteners were sheared to a depth of six threads,
while a fully-engaged screw would penetrate seven threads deep.221 This allowed
McSwain to conclude that the threads were approximately six flats—or one full

screw turn—loose prior to the crash, which is the approximate looseness required
before the engine would fail. Thus, there is some basis for McSwain to conclude that
the carburetor screws were sufficiently loose to cause engine failure.222 That
Lycoming has produced photos that may show the lock tab washers were fully

engaged does not negate the basis for McSwain’s conclusion, but merely creates a
factual issue that a jury must resolve.
With respect to Lycoming’s second argument, Sommer and McSwain have

adequately explained how the engine could have started on the day of the crash, but
then failed after takeoff. As McSwain explained in his most recent report, vibrational
testing revealed that “vibration-induced loosening is rapid, and the throttle body-to-
bowl fastener rotated from finger tight to three head flats loose in approximately one

second. The fastener also rotated from three head flats loose to six head flats loose

220 Id. at 11-12.
221 See also Doc. 622-14 at 3.
222 To the extent that Lycoming contends Sommer failed to disclose that the engine would not
start when the carburetor screws were loosened by four or more flats, the Court disagrees. The
video of Sommer’s testing clearly demonstrates that the engine would not start without some
in approximately one second.”223 This testing demonstrates that it is possible that the
carburetor screws were initially three flats loose and, thus, the engine was able to

start, but that vibration that occurred during takeoff loosened the screws an
additional three flats, meaning that the carburetor screw would be sufficiently loose
that the airplane engine would fail. The Court therefore finds Lycoming’s argument

to be without merit.
Finally, Lycoming’s contention that Sommer failed to consider, let alone rule
out, the post-impact fire as the cause of any loose carburetor screws is likewise
unpersuasive. McSwain testified at the Daubert hearing that lead was found around

the entire carburetor, which indicates that carburetor was loose and leaking fuel prior
to the crash since, had the carburetor looseness occurred post-crash, fuel would be
found on only portions of the carburetor, as gravity would pull the fuel in one

direction. Moreover, in McSwain’s rebuttal report he states that:
Laboratory examination of the carburetor revealed clear evidence of
oscillatory motion and wear between the throttle body fasteners and that
fastener hold walls and between the lock-tab washers and the contracted
throttle body surfaces, both indicative of pre-impact looseness. Based
on the laboratory findings, the hypothesis that the post-impact
looseness condition observed in the subject carburetor [was] caused by
the post-impact fire was rejected.224

It is thus clear from the record that Sommer and McSwain did consider and exclude
the post-crash fire as the cause of the looseness observed in the carburetor. Because

223 Id. at 3-4.
Sommer’s opinion finds sufficient support in the factual record and because he
considered all relevant information when reaching his opinion, there is no basis upon

which to exclude the opinion, and Lycoming’s motion will be denied.
III. CONCLUSION
In accordance with the above discussion, the motions to strike will largely be

denied, although the Court will disallow portions of Edwards’ and Schiefer’s
opinions, consistent with the foregoing discussion.
An appropriate Order follows.

BY THE COURT:

s/ Matthew W. Brann
Matthew W. Brann
United States District Judge

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Source: Frix Law Library, https://www.frixlaw.com/law-library/cases/10409817. Public record. Not legal advice.