Airworthiness Directives; Fairchild Aircraft SA226 and SA227 Series Airplanes

NUCLEAR REGULATORY COMMISSION

DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 93-CE-35-AD; Amendment 39-9180; AD 93-15-02 R1]

Airworthiness Directives; Fairchild Aircraft SA226 and SA227

Series Airplanes

AGENCY: Federal Aviation Administration, DOT.

ACTION: Final rule; request for comments.

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SUMMARY: This amendment revises Airworthiness Directive (AD) 93-15-02,

which requires the following on Fairchild Aircraft SA226 and SA227

series airplanes that are equipped with a certain Simmonds-Precision

pitch trim actuator: repetitively measuring the freeplay of the pitch

trim actuator and repetitively inspecting the actuator for rod

slippage; immediately replacing any actuator if certain freeplay

limitations are not met or rod slippage is evident; and eventually

replacing the actuator regardless of the inspection results. This

action maintains these requirements, but reduces the hours time-in-

service (TIS) before the initial inspection is required, and shortens

both the time period between repetitive inspections and the actuator

replacement compliance time (unless the replacement actuator is new or

if the nut tube assemblies have been replaced during overhaul). An in-

flight incident where the referenced actuator on one of the affected

airplanes failed after accomplishment of the 5,000-hour initial

inspection (with satisfactory results) prompted this action. The

actions specified by this AD are intended to prevent the horizontal

stabilizer from going nose-down or jamming because of pitch trim

actuator failure, which could result in loss of control of the

airplane.

DATES: Effective April 17, 1995.

The incorporation by reference of certain publications listed in

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

of April 17, 1995.

Comments for inclusion in the Rules Docket must be received on or

before June 5, 1995.

ADDRESSES: Submit comments in triplicate to the Federal Aviation

Administration (FAA), Central Region, Office of the Assistant Chief

Counsel, Attention: Rules Docket 93-CE-35-AD, Room 1558, 601 E. 12th

Street, Kansas City, Missouri 64106.

Service information that applies to this AD may be obtained from

Field Support Engineering, Fairchild Aircraft, P.O. Box 790490, San

Antonio, Texas 78279-0490; telephone (210) 824-9421; facsimile (210)

820-8609. This information may also be examined at the FAA, Room 1558,

601 E. 12th Street, Kansas City, Missouri 64106.

FOR FURTHER INFORMATION CONTACT: Mr. Werner Koch, Aerospace Engineer,

FAA, Airplane Certification Office, 2601 Meacham Boulevard, Fort Worth,

Texas 76193-0150; telephone (817) 222-5150; facsimile (817) 222-5959.

SUPPLEMENTARY INFORMATION: AD 93-15-02, Amendment 39-8648 (59 FR 40734,

July 30, 1993), currently requires the following on Fairchild Aircraft

SA226 and SA227 series airplanes that are equipped with a Simmonds-

Precision pitch trim actuator, part number (P/N) DL5040M5: repetitively

measuring the freeplay of the pitch trim actuator and repetitively

inspecting the actuator for rod slippage; and, if certain freeplay

limitations are not met or rod slippage is evident, replacing any

actuator with a new actuator of the same part number or with a part of

improved design, P/N 27-19008-01 or 27-19008-02. The requirements of

the AD will no longer apply when an actuator of improved design is

installed. Accomplishment of the freeplay measurements and inspections

is in accordance with the instructions in Fairchild Aircraft SA226

Series Service Letter (SL) 226-SL-005, and Fairchild Aircraft SA227

Series SL 227-SL-011, both Issued: April 8, 1993, Revised: April 28,

1993, as applicable. Accomplishment of the pitch trim actuator

replacement is in accordance with the applicable maintenance manual.

AD 93-15-02 was issued based on reports of two in-flight incidents

where the above-referenced pitch trim actuator failed on Fairchild

Aircraft SA226 and SA227 series airplanes. In one case, the horizontal

stabilizer went full-nose down, and in the other instance, the

horizontal stabilizer jammed. Fortunately, the pilots were able to

safely land in both of these instances. Upon removal and inspection of

each of these pitch trim actuators, fatigued barrel nuts were found and

the actuator usage time was well over 5,000 hours TIS.

Since AD 93-15-02 became effective, the FAA received a report of an

in-flight incident where the referenced actuator on one of the affected

airplanes failed. The airplane operator had accomplished the 5,000-hour

TIS initial inspection (with satisfactory results), but had not reached

the 6,500-hour TIS mandatory replacement threshold.

Fairchild Aircraft has revised SA226 Series SL 226-SL-005 and SA227

Series SL 227-SL-011 to reflect the revised compliance times and a

change to the inspection procedure. The revision date of this service

information is March 2, 1995.

After examining the circumstances and reviewing all available

information related to the incident described above, the FAA has

determined that AD 93-15-02 should be revised by (1) reducing the

number of hours TIS before the initial inspection is required; and (2)

shortening both the time period between repetitive inspections and the

actuator replacement compliance time, unless the replacement actuator

is new or if the tube nut assemblies have been replaced during

overhaul.

Since an unsafe condition has been identified that is likely to

exist or develop in other Fairchild Aircraft SA226 and SA227 series

airplanes of the same type design that are equipped with a Simmonds-

Precision pitch trim actuator, P/N DL5040M5, this AD requires the same

repetitive inspections and actuator replacement as AD 93-15-02, but

revises the compliance times as previously specified. The inspections

will be accomplished in accordance with the instructions in Fairchild

Aircraft SA226 Series Service Letter (SL) 226-SL-005, and Fairchild

Aircraft SA227 Series SL 227-SL-011, both Issued: April 8, 1993,

Revised: March 2, 1995, as applicable.

Since a situation exists that requires the immediate adoption of

this regulation, it is found that notice and opportunity for public

prior comment [[Page 15668]] hereon are impracticable, and that good

cause exists for making this amendment effective in less than 30 days.

Comments Invited

Although this action is in the form of a final rule that involves

requirements affecting immediate flight safety and, thus, was not

preceded by notice and opportunity to comment, comments are invited on

this rule. Interested persons are invited to comment on this rule by

submitting such written data, views, or arguments as they may desire.

Communications should identify the Rules Docket number and be submitted

in triplicate to the address specified above. All communications

received on or before the closing date for comments will be considered,

and this rule may be amended in light of the comments received. Factual

information that supports the commenter's ideas and suggestions is

extremely helpful in evaluating the effectiveness of the AD action and

determining whether additional rulemaking action would be needed.

Comments are specifically invited on the overall regulatory,

economic, environmental, and energy aspects of the rule that might

suggest a need to modify the rule. All comments submitted will be

available, both before and after the closing date for comments, in the

Rules Docket for examination by interested persons. A report that

summarizes each FAA-public contact concerned with the substance of this

AD will be filed in the Rules Docket.

Commenters wishing the FAA to acknowledge receipt of their comments

submitted in response to this notice must submit a self-addressed,

stamped postcard on which the following statement is made: ``Comments

to Docket No. 93-CE-35-AD.'' The postcard will be date stamped and

returned to the commenter.

The regulations adopted herein will not have substantial direct

effects 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, in

accordance with Executive Order 12612, it is determined that this final

rule does not have sufficient federalism implications to warrant the

preparation of a Federalism Assessment.

The FAA has determined that this regulation is an emergency

regulation and that it is not considered to be significant under

Executive Order 12866. It is impracticable for the agency to follow the

procedures of Executive Order 12866 with respect to this rule since the

rule must be issued immediately to correct an unsafe condition in

aircraft. It has been determined further that this action involves an

emergency regulation under DOT Regulatory Policies and Procedures (44

FR 11034, February 26, 1979). If it is determined that this emergency

regulation otherwise would be significant under DOT Regulatory Policies

and Procedures, a final regulatory evaluation will be prepared and

placed in the Rules Docket (otherwise, an evaluation is not required).

A copy of it, if filed, may be obtained from the Rules Docket.

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. App. 1354(a), 1421 and 1423; 49 U.S.C.

106(g); and 14 CFR 11.89.

Sec. 39.13 [Amended]

2. Section 39.13 is amended by removing Amendment 39-8648 (59 FR

40734, July 30, 1993), and by adding a new airworthiness directive to

read as follows:

93-15-02 R1 Fairchild Aircraft: Amendment 39-9180; Docket No. 93-

CE-35-AD. Revises AD 93-15-02, Amendment 39-8648.

Applicability: All SA226 and SA227 series airplanes (all models

and serial numbers) that are equipped with a Simmonds-Precision

pitch trim actuator, part number (P/N) DL5040M5, certificated in any

category.

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 use the authority

provided in paragraph (d) of this AD to request approval from the

FAA. This approval may address either no action, if the current

configuration eliminates the unsafe condition, or different actions

necessary to address the unsafe condition described in this AD. Such

a request should include an assessment of the effect of the changed

configuration on the unsafe condition addressed by this AD. In no

case does the presence of any modification, alteration, or repair

remove any aircraft from the applicability of this AD.

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

already accomplished.

To prevent the horizontal stabilizer from going nose down or

jamming because of pitch trim actuator failure, 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 2 and Level 3 structures are designations of the Level 1

paragraph they immediately follow.

(a) Upon accumulating 3,000 hours time-in-service (TIS) on a

Simmonds-Precision pitch trim actuator, P/N DL5040M5, or within the

next 50 hours TIS accumulated on this type pitch trim actuator after

the effective date of this AD, whichever occurs later, unless

already accomplished, and thereafter at intervals not to exceed 250

hours TIS until paragraph (b) is complied with, accomplish the

following:

Note 3: If hours TIS accumulated on the pitch trim actuator are

not maintained, then hours TIS accumulated on the airplane may be

substituted.

(1) Measure the freeplay of the pitch trim actuator and inspect

the actuator for rod slippage in accordance with the INSTRUCTIONS

section of Fairchild Aircraft SA226 Series Service Letter (SL) 226-

SL-005, and Fairchild Aircraft SA227 Series SL 227-SL-011, both

issued: April 8, 1993, revised: March 2, 1995, as applicable.

(2) If certain freeplay limitations specified in the service

letters are not met or rod slippage is evident, prior to further

flight, accomplish the replacement specified in either paragraph

(b)(1) or (b)(2) of this AD.

(b) Within 500 hours TIS after the inspection specified in

paragraph (a) of this AD or upon accumulating 5,000 hours TIS on a

Simmonds-Precision pitch trim actuator, P/N DL5040M5, whichever

occurs later, accomplish one of the following:

(1) Replace the pitch trim actuator with a new part of the same

design and part number in accordance with the instructions in the

applicable maintenance manual. Reinspect as specified in paragraph

(a) of this AD at intervals not to exceed 300 hours TIS, and replace

the actuator as specified in paragraph (b) of this AD at intervals

not to exceed 6,500 hours TIS.

(2) Replace the pitch trim actuator with an overhauled, zero-

timed part of the same design and part number. Accomplish this

replacement in accordance with the instructions in the applicable

maintenance manual, and reinspect and replace as specified below

(paragraphs (b)(2)(i) and (b)(2)(ii) of this AD):

(i) If both nut tube assemblies, P/N AA56142, were replaced with

new assemblies during overhaul, reinspect as specified in paragraph

(a) of this AD at intervals not to exceed 300 hours TIS, and

[[Page 15669]] replace the actuator as specified in paragraph (b) of

this AD at intervals not to exceed 6,500 hours TIS;

(ii) If both nut tube assemblies, P/N AA56142, were not replaced

with new assemblies during overhaul, reinspect as specified in

paragraph (a) of this AD at intervals not to exceed 250 hours TIS,

and replace the actuator as specified in paragraph (b) of this AD at

intervals not to exceed 5,000 hours TIS.

(3) Replace the pitch trim actuator with a new part of improved

design, P/N 27-19008-01 or 27-19008-02, in accordance with the

instructions in the applicable maintenance manual.

(i) This replacement eliminates the repetitive inspection

requirement of this AD.

(ii) This replacement may be accomplished at any time to

eliminate the inspection requirement of this AD.

(c) 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.

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

initial or repetitive compliance times that provides an equivalent

level of safety may be approved by the Manager, Airplane

Certification Office (ACO), FAA, 2601 Meacham Boulevard, Fort Worth,

Texas 76193-0150. The request shall be forwarded through an

appropriate FAA Maintenance Inspector, who may add comments and then

send it to the Manager, Fort Worth ACO.

Note 4: Information concerning the existence of approved

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

obtained from the Fort Worth ACO.

(e) The inspections and modification required by this AD shall

be done in accordance with Fairchild Aircraft SA226 Series Service

Letter 226-SL-005, and Fairchild Aircraft SA227 Series Service

Letter 227-SL-011, both Issued: April 8, 1993, Revised: March 2,

1995, as applicable. This incorporation by reference is 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 Field Support

Engineering, Fairchild Aircraft, P.O. Box 790490, San Antonio, Texas

78279-0490. Copies may be inspected at the FAA, Central Region,

Office of the Assistant Chief Counsel, Room 1558, 601 E. 12th

Street, Kansas City, Missouri, or at the Office of the Federal

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

(f) This amendment (39-9180) becomes effective on April 17,

1995.

Issued in Kansas City, Missouri, on March 17, 1995.

Dwight A. Young,

Acting Manager, Small Airplane Directorate, Aircraft Certification

Service.

[FR Doc. 95-7113 Filed 3-24-95; 8:45 am]

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