Airworthiness Directives; The New Piper Aircraft, Inc. J-2 Series Airplanes That Are Equipped With Wing Lift Struts

DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 99-CE-13-AD; Amendment 39-11479; AD 99-26-19]

RIN 2120-AA64

Airworthiness Directives; The New Piper Aircraft, Inc. J-2 Series

Airplanes That Are Equipped With Wing Lift Struts

AGENCY: Federal Aviation Administration, DOT.

ACTION: Final rule.

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SUMMARY: This amendment adopts a new airworthiness directive (AD) that

applies to certain The New Piper Aircraft, Inc. (Piper) J-2 series

airplanes equipped with wing lift struts. This AD requires repetitively

inspecting the wing lift struts for dents and corrosion and the wing

lift strut forks for cracks; replacing any strut found with corrosion

or dents, or forks with cracks; and repetitively replacing the wing

lift strut forks. This AD also requires incorporating a ``NO STEP''

placard on the lift strut. This AD is the result of the Federal

Aviation Administration (FAA) inadvertently omitting the J-2 series

airplanes from the applicability of AD 99-01-05. The actions specified

by this AD are intended to prevent in-flight separation of the wing

from the airplane caused by wing lift struts with dents or corrosion or

wing lift forks with cracks, which could result in loss of control of

the airplane.

DATES: Effective February 14, 2000.

The incorporation by reference of certain publications listed in

the regulations is approved by the Director of the Federal Register as

of February 14, 2000.

ADDRESSES: Service information that applies to this AD may be obtained

from The New Piper Aircraft, Inc., Customer Services, 2926 Piper Drive,

Vero Beach, Florida 32960. Copies of the instructions to the F. Atlee

Dodge supplemental type certificate (STC) may be obtained from F. Atlee

Dodge, Aircraft Services, Inc., P.O. Box 190409, Anchorage, Alaska

99519-0409. Copies of the instructions to the Jensen Aircraft STC's may

be obtained from Jensen Aircraft, Inc., 9225 County Road 140, Salida,

Colorado 81201. This information may also be examined at the Federal

Aviation Administration (FAA), Central Region, Office of the Regional

Counsel, Attention: Rules Docket No. 99-CE-13-AD, 901 Locust, Room 506,

Kansas City, Missouri 64106; or at the Office of the Federal Register,

800 North Capitol Street, NW, suite 700, Washington, DC.

FOR FURTHER INFORMATION CONTACT: Mr. William O. Herderich, Aerospace

Engineer, FAA, Atlanta Aircraft Certification Office, One Crown Center,

1895 Phoenix Boulevard, suite 450, Atlanta, Georgia 30349; telephone:

(770) 703-6084; facsimile: (770) 703-6097.

SUPPLEMENTARY INFORMATION:

Events Leading to the Issuance of This AD

A proposal to amend part 39 of the Federal Aviation Regulations (14

CFR part 39) to include an AD that would apply to certain Piper J-2

series airplanes of the same type design that are equipped with wing

lift struts was published in the Federal Register as a notice of

proposed rulemaking (NPRM) on July 12, 1999 (64 FR 37465). The NPRM

proposed to require repetitively inspecting the wing lift struts for

dents and corrosion and the wing lift strut forks for cracks; replacing

any strut found with corrosion or dents, or forks with cracks; and

repetitively replacing the wing lift strut forks. The NPRM also

proposed to require installing a placard on the lift strut, and would

provide the option of installing certain wing lift strut and wing lift

strut fork assemblies, as terminating action for repetitive inspection

and replacement requirements. Accomplishment of the proposed action as

specified in the NPRM would be required in accordance with Piper

Service bulletin No. 528D, dated October 19,1990.

The NPRM was the result of the Federal Aviation Administration

(FAA) inadvertently omitting the J-2 series airplanes from the

applicability of AD 99-01-05.

Interested persons have been afforded an opportunity to participate

in the making of this amendment. No comments were received on the

proposed rule or the FAA's determination of the cost to the public.

The FAA's Determination

After careful review of all available information related to the

subject presented above, the FAA has determined that air safety and the

public interest require the adoption of the rule as proposed except for

minor editorial corrections. The FAA has determined that these minor

corrections will not change the meaning of the AD and will not add any

additional burden upon the public than was already proposed.

[[Page 72525]]

Cost Impact

The FAA estimates that 91 airplanes in the U.S. registry will be

affected by this AD.

It will take approximately 8 workhours per airplane to accomplish

the initial inspection, and the average labor rate is approximately $60

an hour. Based on these figures, the total cost impact of the initial

inspection on U.S. operators is estimated to be $43,680, or $480 per

airplane. These figures are based only on the cost of the initial

inspection and do not take into account the costs of any repetitive

inspections. The FAA has no way of determining how many repetitive

inspections each owner/operator will incur over the life of the

airplane.

It will take approximately 4 workhours per airplane to accomplish

the initial wing lift strut fork replacements, and the average labor

rate is approximately $60 an hour. Fork assemblies cost approximately

$110 each and four are required for each airplane. Based on these

figures, the total cost impact of the initial wing lift strut fork

replacements on U.S. operators is estimated to be $61,880, or $680 per

airplane.

Airplane operators who do not incorporate the improved design wing

lift strut assemblies will have to repetitively replace the wing lift

strut forks. The FAA has no way of determining how many airplanes do

not have the improved design wing lift strut assemblies installed and

will need repetitive strut fork replacements.

Regulatory Impact

The regulations adopted herein will not have a substantial direct

effect on the States, on the relationship between the national

Government and the States, or on the distribution of power and

responsibilities among the various levels of government. Therefore, it

is determined that this final rule does not have federalism

implications under Executive Order 13132.

For the reasons discussed above, I certify that this action (1) is

not a ``significant regulatory action'' under Executive Order 12866;

(2) is not a ``significant rule'' under DOT Regulatory Policies and

Procedures (44 FR 11034, February 26, 1979); and (3) will not have a

significant economic impact, positive or negative, on a substantial

number of small entities under the criteria of the Regulatory

Flexibility Act. A copy of the final evaluation prepared for this

action is contained in the Rules Docket. A copy of it may be obtained

by contacting the Rules Docket at the location provided under the

caption ADDRESSES.

List of Subjects in 14 CFR Part 39

Air transportation, Aircraft, Aviation safety, Incorporation by

reference, Safety.

Adoption of the Amendment

Accordingly, pursuant to the authority delegated to me by the

Administrator, the Federal Aviation Administration amends part 39 of

the Federal Aviation Regulations (14 CFR part 39) as follows:

PART 39--AIRWORTHINESS DIRECTIVES

1. The authority citation for part 39 continues to read as follows:

Authority: 49 U.S.C. 106(g), 40113, 44701.

Sec. 39.13 [Amended]

2. Section 39.13 is amended by adding a new airworthiness directive

(AD) to read as follows:

99-26-19 The New Piper Aircraft, Inc.: Amendment 39-11479; Docket

No. 99-CE-13-AD.

Applicability: J-2 series airplanes, serial numbers 500 through

1975, certificated in any category; that are equipped with wing lift

struts.

Note 1: This AD applies to each airplane identified in the

preceding applicability provision, regardless of whether it has been

modified, altered, or repaired in the area subject to the

requirements of this AD. For airplanes that have been modified,

altered, or repaired so that the performance of the requirements of

this AD is affected, the owner/operator must request approval for an

alternative method of compliance in accordance with paragraph (f) of

this AD. The request should include an assessment of the effect of

the modification, alteration, or repair on the unsafe condition

addressed by this AD; and, if the unsafe condition has not been

eliminated, the request should include specific proposed actions to

address it.

Compliance: Required as indicated in the body of this AD, unless

already accomplished.

To prevent in-flight separation of the wing from the airplane

caused by wing lift struts with dents or corrosion or wing lift

forks with cracks, which could result in loss of control of the

airplane, accomplish the following:

Note 2: The paragraph structure of this AD is as follows:

Level 1: (a), (b), (c), etc.

Level 2: (1), (2), (3), etc.

Level 3: (i), (ii), (iii), etc.

Level 4: (A), (B), (C), etc.

Level 2, Level 3, and Level 4 structures are designations of the

Level 1 paragraph they immediately follow.

(a) Within 1 calendar month after the effective date of this AD

or within 24 calendar months after the last inspection accomplished

per AD 93-10-06, whichever occurs later, remove the wing lift struts

in accordance with Piper Service Bulletin (SB) No. 528D, and

accomplish one of the following (the actions in either paragraph

(a)(1), (a)(2), (a)(3), or (a)(4), including subparagraphs, of this

AD):

(1) Inspect the wing lift struts for perceptible dents (as

defined in the service bulletin referenced below) and corrosion in

accordance with the ``INSTRUCTIONS'' section in part I of Piper SB

No. 528D, dated October 19, 1990.

(i) If no perceptible dents are found in the wing lift strut and

no corrosion is externally visible, prior to further flight, apply

corrosion inhibitor to each strut in accordance with the SB

referenced above. Reinspect the lift struts at intervals not to

exceed 24 calendar months.

(ii) If a perceptible dent is found in the wing lift strut or

external corrosion is found, prior to further flight, accomplish one

of the installations (and subsequent actions presented in each

paragraph) specified in paragraph (a)(3) or (a)(4) of this AD.

(2) Inspect the wing lift struts for corrosion in accordance

with the Appendix to this AD. The inspection procedures in this

Appendix must be accomplished by a Level 2 inspector certified using

the guidelines established by the American Society for Non-

destructive Testing, or MIL-STD-410.

(i) If no corrosion is found that is externally visible and all

requirements in the Appendix to this AD are met, prior to further

flight, apply corrosion inhibitor to each strut in accordance with

the SB referenced above. Reinspect the lift struts at intervals not

to exceed 24 calendar months.

(ii) If external corrosion is found or if any of the

requirements in the Appendix of this AD are not met, prior to

further flight, accomplish one of the installations (and subsequent

actions presented in each paragraph) specified in paragraph (a)(3)

or (a)(4) of this AD.

(3) Install original equipment manufacturer (OEM) part number

wing struts (or FAA-approved equivalent part numbers) that have been

inspected in accordance with the specifications presented in either

paragraph (a)(1) or (a)(2) of this AD, and are found to be airworthy

according to the inspection requirements included in these

paragraphs. Thereafter, inspect these wing lift struts at intervals

not to exceed 24 calendar months in accordance with the

specifications presented in either paragraph (a)(1) or (a)(2) of

this AD.

(4) Install new sealed wing lift strut assemblies, part numbers

as specified in Piper SB No. 528D (or FAA-approved equivalent part

numbers), on each wing as specified in the INSTRUCTIONS section in

part II of the above-referenced SB. These sealed wing lift strut

assemblies also include the wing lift strut forks. Installation of

these assemblies constitutes terminating action for the inspection

and replacement requirements of both paragraphs (a) and (b) of this

AD.

(b) Within the next 100 hours time-in-service (TIS) after the

effective date of this AD or within 500 hours TIS after the last

inspection, whichever is later, remove the wing lift strut forks and

accomplish one of the following (the actions in either paragraph

(b)(1), (b)(2) or (b)(3); including subparagraphs, of this AD):

[[Page 72526]]

(1) Inspect the wing lift strut forks for cracks using FAA-

approved magnetic particle procedures.

(i) If no cracks are found, reinspect at intervals not to exceed

500 hours TIS provided that the replacement requirements of

paragraphs (b)(1)(ii)(B) and (b)(1)(ii)(C) of this AD have been met.

(ii) Replace the wing lift strut forks at whichever of the

following is applicable:

(A) If cracks are found on any wing lift strut fork: Prior to

further flight;

(B) If the airplane is equipped with floats or has been equipped

with floats within the last 2,000 hours TIS and no cracks are found

during the above inspections: Upon accumulating 1,000 hours TIS on

the wing lift strut forks or within the next 100 hours TIS after the

effective date of this AD, whichever occurs later; or

(C) If the airplane has not been equipped with floats within the

last 2,000 hours TIS and no cracks are found during the above

inspections: Upon accumulating 2,000 hours TIS on the wing lift

strut forks or within the next 100 hours TIS after the effective

date of this AD, whichever occurs later.

(iii) Replacement parts shall be of the same part numbers of the

existing part (or FAA-approved equivalent part numbers) and shall be

manufactured with rolled threads. Lift strut forks manufactured with

machined (cut) threads shall not be utilized.

(iv) The 500-hour TIS interval repetitive inspections are still

required when the above replacements are accomplished.

(2) Install new OEM part number wing lift strut forks (or FAA-

approved equivalent part numbers). Reinspect and replace these wing

lift strut forks at the intervals specified in paragraphs (b)(1)(i),

(b)(1)(ii), (b)(1)(iii), and (b)(1)(iv), including all

subparagraphs, of this AD.

(3) Install new sealed wing lift strut assemblies, part numbers

as specified in Piper SB No. 528D (or FAA-approved equivalent part

numbers), on each wing as specified in the INSTRUCTIONS section in

part II of the above-referenced SB.

(i) This installation may have ``already been accomplished''

through the actions specified in paragraph (a)(4) of this AD.

(ii) No repetitive inspections are required after installing

these sealed wing lift strut assemblies.

(c) If holes are drilled in wing lift strut assemblies installed

in accordance with (a)(4) or (b)(3) of this AD to attach cuffs, door

clips, or other hardware, inspect the wing lift struts at intervals

not to exceed 24 calendar months using the procedures specified in

paragraph (a)(1) or (a)(2), including all subparagraphs, of this AD.

(d) Within 1 calendar month after the effective date of this AD

and thereafter prior to further flight after the installation of any

lift strut assembly, accomplish one of the following:

(1) Install ``NO STEP'' decal, Piper part number (P/N) 80944-02,

on each wing lift strut approximately 6 inches from the bottom of

the struts in a way that the letters can be read when entering and

exiting the aircraft; or

(2) Paint the statement ``NO STEP'' approximately 6 inches from

the bottom of the struts in a way that the letters can be read when

entering and exiting the aircraft. Use a minimum of 1-inch letters

utilizing a color that contrasts with the color of the airplane.

(e) Special flight permits may be issued in accordance with

sections 21.197 and 21.199 of the Federal Aviation Regulations (14

CFR 21.197 and 21.199) to operate the airplane to a location where

the requirements of this AD can be accomplished.

(f) An alternative method of compliance or adjustment of the

initial and repetitive compliance times that provides an equivalent

level of safety may be approved by the Manager, FAA, Atlanta Aircraft

Certification Office (ACO), One Crown Center, 1895 Phoenix Boulevard,

suite 450, Atlanta, Georgia 30349. The request shall be forwarded

through an appropriate FAA Maintenance Inspector, who may add comments

and then send it to the Manager, Atlanta ACO.

Note 3: Information concerning the existence of approved

alternative methods of compliance with this AD, if any, may be

obtained from the Atlanta ACO.

(g) The removals, inspections, modifications, and installations

required by this AD shall be done in accordance with Piper Service

Bulletin No. 528D, dated October 19, 1990. This incorporation by

reference was approved by the Director of the Federal Register in

accordance with 5 U.S.C. 552(a) and 1 CFR part 51. Copies may be

obtained from The New Piper Aircraft, Inc., Customer Services, 2926

Piper Drive, Vero Beach, Florida 32960. Copies may be inspected at

the FAA, Central Region, Office of the Regional Counsel, 901 Locust,

Room 506, Kansas City, Missouri, or at the Office of the Federal

Register, 800 North Capitol Street, NW, suite 700, Washington, DC.

Appendix to Docket No. 99-CE-13-AD--Procedures and Requirements for

Ultrasonic Inspection of Piper Wing Lift Struts

Equipment Requirements

1. A portable ultrasonic thickness gauge or flaw detector with

echo-to-echo digital thickness readout capable of reading to 0.001-

inch and an A-trace waveform display will be needed to accomplish

this inspection.

2. An ultrasonic probe with the following specifications will be

needed to accomplish this inspection: 10 MHz (or higher), 0.283-inch

(or smaller) diameter dual element or delay line transducer designed

for thickness gauging. The transducer and ultrasonic system shall be

capable of accurately measuring the thickness of AISI 4340 steel

down to 0.020-inch. An accuracy of +/-0.002-inch throughout a 0.020-

inch to 0.050-inch thickness range while calibrating shall be the

criteria for acceptance.

3. Either a precision machined step wedge made of 4340 steel (or

similar steel with equivalent sound velocity) or at least three shim

samples of same material will be needed to accomplish this

inspection. One thickness of the step wedge or shim shall be less

than or equal to 0.020-inch, one shall be greater than or equal to

0.050-inch, and at least one other step or shim shall be between

these two values.

4. Glycerin, light oil, or similar non-water based ultrasonic

couplants are recommended in the setup and inspection procedures.

Water-based couplants, containing appropriate corrosion inhibitors,

may be utilized, provided they are removed from both the reference

standards and the test item after the inspection procedure is

completed and adequate corrosion prevention steps are then taken to

protect these items.

Note: Couplant is defined as ``a substance used between

the face of the transducer and test surface to improve transmission

of ultrasonic energy across the transducer/strut interface.''

Note: If surface roughness due to paint loss or

corrosion is present, the surface should be sanded or polished

smooth before testing to assure a consistent and smooth surface for

making contact with the transducer. Care shall be taken to remove a

minimal amount of structural material. Paint repairs may be

necessary after the inspection to prevent further corrosion damage

from occurring. Removal of surface irregularities will enhance the

accuracy of the inspection technique.

Instrument Setup

1. Set up the ultrasonic equipment for thickness measurements as

specified in the instrument's user's manual. Because of the variety

of equipment available to perform ultrasonic thickness measurements,

some modification to this general setup procedure may be necessary.

However, the tolerance requirement of step 13 and the record keeping

requirement of step 14, must be satisfied.

2. If battery power will be employed, check to see that the

battery has been properly charged. The testing will take

approximately two hours. Screen brightness and contrast should be

set to match environmental conditions.

3. Verify that the instrument is set for the type of transducer

being used, i.e. single or dual element, and that the frequency

setting is compatible with the transducer.

4. If a removable delay line is used, remove it and place a drop

of couplant between the transducer face and the delay line to assure

good transmission of ultrasonic energy. Reassemble the delay line

transducer and continue.

5. Program a velocity of 0.231-inch/microsecond into the

ultrasonic unit unless an alternative instrument calibration

procedure is used to set the sound velocity.

6. Obtain a step wedge or steel shims per item 3 of the

Equipment Requirements. Place the probe on the thickest sample using

couplant. Rotate the transducer slightly back and forth to ``ring''

the transducer to the sample. Adjust the delay and range settings to

arrive at an A-trace signal display with the first backwall echo

from the steel near the left side of the screen and the second

backwall echo near the right of the screen. Note that when a single

element transducer is used, the initial pulse and the delay line/

steel interface will be off of the screen to the left. Adjust the

gain to place the amplitude of the first backwall signal at

approximately 80% screen height on the A-trace.

[[Page 72527]]

7. ``Ring'' the transducer on the thinnest step or shim using

couplant. Select positive half-wave rectified, negative half-wave

rectified, or filtered signal display to obtain the cleanest signal.

Adjust the pulse voltage, pulse width, and damping to obtain the

best signal resolution. These settings can vary from one transducer

to another and are also user dependent.

8. Enable the thickness gate, and adjust the gate so that it

starts at the first backwall echo and ends at the second backwall

echo. (Measuring between the first and second backwall echoes will

produce a measurement of the steel thickness that is not affected by

the paint layer on the strut). If instability of the gate trigger

occurs, adjust the gain, gate level, and/or damping to stabilize the

thickness reading.

9. Check the digital display reading and if it does not agree

with the known thickness of the thinnest thickness, follow your

instrument's calibration recommendations to produce the correct

thickness reading. When a single element transducer is used this

will usually involve adjusting the fine delay setting.

10. Place the transducer on the thickest step of shim using

couplant. Adjust the thickness gate width so that the gate is

triggered by the second backwall reflection of the thick section. If

the digital display does not agree with the thickest thickness,

follow your instruments calibration recommendations to produce the

correct thickness reading. A slight adjustment in the velocity may

be necessary to get both the thinnest and the thickest reading

correct. Document the changed velocity value.

11. Place couplant on an area of the lift strut which is thought

to be free of corrosion and ``ring'' the transducer to surface.

Minor adjustments to the signal and gate settings may be required to

account for coupling improvements resulting from the paint layer.

The thickness gate level should be set just high enough so as not to

be triggered by irrelevant signal noise. An area on the upper

surface of the lift strut above the inspection area would be a good

location to complete this step and should produce a thickness

reading between 0.034-inch and 0.041-inch.

12. Repeat steps 8, 9, 10, and 11 until both thick and thin shim

measurements are within tolerance and the lift strut measurement is

reasonable and steady.

13. Verify that the thickness value shown in the digital display

is within +/-0.002-inch of the correct value for each of the three

or more steps of the setup wedge or shims. Make no further

adjustments to the instrument settings.

14. Record the ultrasonic versus actual thickness of all wedge

steps or steel shims available as a record of setup.

Inspection Procedure

1. Clean the lower 18 inches of the wing lift struts using a

cleaner that will remove all dirt and grease. Dirt and grease will

adversely affect the accuracy of the inspection technique. Light

sanding or polishing may also be required to reduce surface

roughness as noted in the Equipment Requirements section.

2. Using a flexible ruler, draw a \1/4\-inch grid on the surface

of the first 11 inches from the lower end of the strut as shown in

Piper Service Bulletin No. 528D or 910A, as applicable. This can be

done using a soft (#2) pencil and should be done on both faces of

the strut. As an alternative to drawing a complete grid, make two

rows of marks spaced every \1/4\-inch across the width of the strut.

One row of marks should be about 11 inches from the lower end of the

strut, and the second row should be several inches away where the

strut starts to narrow. Lay the flexible ruler between respective

tick marks of the two rows and use tape or a rubber band to keep the

ruler in place. See Figure 1.

3. Apply a generous amount of couplant inside each of the square

areas or along the edge of the ruler. Re-application of couplant may

be necessary.

4. Place the transducer inside the first square area of the

drawn grid or at the first \1/4\-inch mark on the ruler and ``ring''

the transducer to the strut. When using a dual element transducer,

be very careful to record the thickness value with the axis of the

transducer elements perpendicular to any curvature in the strut. If

this is not done, loss of signal or inaccurate readings can result.

5. Take readings inside each square on the grid or at \1/4\-inch

increments along the ruler and record the results. When taking a

thickness reading, rotate the transducer slightly back and forth and

experiment with the angle of contact to produce the lowest thickness

reading possible. Pay close attention to the A-scan display to

assure that the thickness gate is triggering off of maximized

backwall echoes.

Note: A reading shall not exceed .041-inch. If a

reading exceeds .041-inch, repeat steps 13 and 14 of the Instrument

Setup section before proceeding further.

6. If the A-trace is unsteady or the thickness reading is

clearly wrong, adjust the signal gain and/or gate setting to obtain

reasonable and steady readings. If any instrument setting is

adjusted, repeat steps 13 and 14 of the Instrument Setup section

before proceeding further.

7. In areas where obstructions are present, take a data point as

close to the correct area as possible.

Note: The strut wall contains a fabrication bead at

approximately 40% of the strut chord. The bead may interfere with

accurate measurements in that specific location.

8. A measurement of 0.024-inch or less shall require replacement

of the strut prior to further flight

9. If at any time during testing an area is encountered where a

valid thickness measurement cannot be obtained due to a loss of

signal strength or quality, the area shall be considered suspect.

These areas may have a remaining wall thickness of less than 0.020-

inch, which is below the range of this setup, or they may have small

areas of localized corrosion or pitting present. The latter case

will result in a reduction in signal strength due to the sound being

scattered from the rough surface and may result in a signal that

includes echoes from the pits as well as the backwall. The suspect

area(s) shall be tested with a Maule ``Fabric Tester'' as specified

in Piper Service Bulletin No. 528D or 910A.

10. Record the lift strut inspection in the aircraft log book.

[[Page 72528]]

[GRAPHIC] [TIFF OMITTED] TR28DE99.022

(h) This amendment becomes effective on February 14, 2000.

Issued in Kansas City, Missouri, on December 16, 1999.

James Jackson,

Acting Manager, Small Airplane Directorate, Aircraft Certification

Service.

[FR Doc. 99-33166 Filed 12-27-99; 8:45 am]

BILLING CODE 4910-13-U