Airworthiness directives: Lockheed,

[Federal Register: August 13, 1998 (Volume 63, Number 156)]

[Proposed Rules]

[Page 43340-43342]

From the Federal Register Online via GPO Access [wais.access.gpo.gov]

[DOCID:fr13au98-23]

DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 98-NM-84-AD]

RIN 2120-AA64

Airworthiness Directives; Lockheed Model L-188A and L-188C Series Airplanes

AGENCY: Federal Aviation Administration, DOT.

ACTION: Notice of proposed rulemaking (NPRM).

SUMMARY: This document proposes the adoption of a new airworthiness directive (AD) that is applicable to all Lockheed Model L-188A and L- 188C series airplanes. This proposal would require revising the Airplane Flight Manual to provide the flightcrew with modified procedures and limitations for operating in icing conditions. This proposal is prompted by incidents and accidents involving airplanes equipped with turboprop engines that experienced tailplane stall due to ice accretion on the horizontal stabilizer of the airplane. The actions specified by the proposed AD are intended to prevent undetected accretion of ice on the horizontal stabilizer, which could result in ice contaminated tailplane stall and consequent loss of pitch control.

DATES: Comments must be received by September 28, 1998.

ADDRESSES: Submit comments in triplicate to the Federal Aviation Administration (FAA), Transport Airplane Directorate, ANM-114, Attention: Rules Docket No. 98-NM-84-AD, 1601 Lind Avenue, SW., Renton, Washington 98055-4056. Comments may be inspected at this location between 9:00 a.m. and 3:00 p.m., Monday through Friday, except Federal holidays.

The service information referenced in the proposed rule may be obtained from Lockheed Aeronautical Systems Support Company (LASSC), Field Support Department, Dept. 693, Zone 0755, 2251 Lake Park Drive, Smyrna, Georgia 30080. This information may be examined at the FAA, Transport Airplane Directorate, 1601 Lind Avenue, SW., Renton, Washington; or at the FAA, Small Airplane Directorate, Atlanta Aircraft Certification Office, One Crown Center, 1895 Phoenix Boulevard, suite 450, Atlanta, Georgia.

FOR FURTHER INFORMATION CONTACT: Thomas Peters, Aerospace Engineer, Systems and Flight Test Branch, ACE-116A, FAA, Small Airplane Directorate, Atlanta Aircraft Certification Office, One Crown Center, 1895 Phoenix Boulevard, suite 450, Atlanta, Georgia 30337-2748; telephone (770) 703-6063; fax (770) 703-6097.

SUPPLEMENTARY INFORMATION:

Comments Invited

Interested persons are invited to participate in the making of the proposed rule by submitting such written data, views, or arguments as they may desire. Communications shall 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, specified above, will be considered before taking action on the proposed rule. The proposals contained in this notice may be changed in light of the comments received.

Comments are specifically invited on the overall regulatory, economic, environmental, and energy aspects of the proposed 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 summarizing each FAA-public contact concerned with the substance of this proposal will be filedin 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 Number 98-NM-84-AD.'' The postcard will be date stamped and returned to the commenter.

Availability of NPRMs

Any person may obtain a copy of this NPRM by submitting a request to the FAA, Transport Airplane Directorate, ANM-114, Attention: Rules Docket No. 98-NM-84-AD, 1601 Lind Avenue, SW., Renton, Washington 98055-4056.

Discussion

Several accidents and reported incidents that involved airplanes equipped with turboprop engines prompted the FAA to research the predicted characteristics of tailplane stall in airplanes equipped with turboprop engines. Results of that research indicated that airplanes equipped with turboprop engines were susceptible to incidents of tailplane stall when the effects of strong slipstream downwash from the propellers were combined with ice accretion on the leading edge of the horizontal stabilizer.

As a result of that research, Lockheed Model L-188A and L-188C series airplanes were determined possibly to be susceptible to such incidents of tailplane stall. It was discovered that a higher accretion efficiency of the leading edge of the horizontal tail could result in ice accretions not being detected by the flightcrew, which could lead to a delay in activation of the ice protection system. Such undetected accretion of ice on the horizontal stabilizer of the airplane, if not corrected, could result in ice contaminated tailplane stall and consequent loss of pitch control.

FAA's Determination

In light of this information, the FAA finds that certain procedures should be included in the FAA-approved AFM's for these airplanes to provide the flightcrew with modified procedures and limitations for operating in icing conditions and to take appropriate action to prevent accretion of ice on the horizontal stabilizer of the airplane in certain icing conditions. The FAA has determined that such procedures currently are not defined adequately in the AFM for these airplanes.

[[Page 43341]]

Explanation of Relevant Service Information

The FAA has reviewed and approved revisions, dated December 1, 1997, and March 10, 1998, for incorporation into the Limitations, Normal Procedures, and Performance Sections and Appendix III of the FAA-approved Electra 188A Airplane Flight Manual (AFM). These revisions provide the flightcrew with modified procedures and limitations for operating in icing conditions. The revisions specify that, when flying in icing conditions with the flaps extended, the flightcrew should maintain the leading edge of the horizontal stabilizer at a temperature of 25 degrees Celsius or higher using the empennage ice protection system or, alternatively, the empennage ice protection system may be activated and operated continuously in an anti-ice mode.

The FAA also has reviewed and approved revisions, dated December 1, 1997, and March 10, 1998, for incorporation into the Limitations, Normal Procedures, and Performance Sections and Appendix III of the FAA-approved Electra 188C AFM. These revisions are similar to the revisions to the Electra 188A AFM described previously.

Explanation of Requirements of Proposed Rule

Since an unsafe condition has been identified that is likely to exist or develop on other products of this same type design, the proposed AD would require revising the Limitations, Normal Procedures, and Performance Sections and Appendix III of the Electra 188A and 188C AFM's to provide the flightcrew with modified procedures and limitations for operating in icing conditions.

Cost Impact

There are approximately 75 airplanes of the affected design in the worldwide fleet. The FAA estimates that 32 airplanes of U.S. registry would be affected by this proposed AD, that it would take approximately 1 work hour per airplane to accomplish the proposed incorporation of the AFM revisions, and that the average labor rate is $60 per work hour. Based on these figures, the cost impact of the proposed AD on U.S. operators is estimated to be $1,920, or $60 per airplane.

The cost impact figure discussed above is based on assumptions that no operator has yet accomplished any of the proposed requirements of this AD action, and that no operator would accomplish those actions in the future if this AD were not adopted.

Regulatory Impact

The regulations proposed herein would 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 proposal would not have sufficient federalism implications to warrant the preparation of a Federalism Assessment.

For the reasons discussed above, I certify that this proposed regulation (1) is not a ``significant regulatory action'' under Executive Order 12866; (2) is not a ``significant rule'' under the DOT Regulatory Policies and Procedures (44 FR 11034, February 26, 1979); and (3) if promulgated, 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 draft regulatory 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, Safety.

The Proposed Amendment

Accordingly, pursuant to the authority delegated to me by the Administrator, the Federal Aviation Administration proposes to amend 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 the following new airworthiness directive:

   Lockheed: Docket 98-NM-84-AD.

   Applicability: All Model L-188A and L-188C series airplanes, 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 request approval for an alternative method of compliance in accordance with paragraph (b) 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, unless accomplished previously.

   To prevent undetected accretion of ice on the horizontal stabilizer, which could result in ice contaminated tailplane stall and consequent loss of pitch control, accomplish the following:

   (a) Within 30 days after the effective date of this AD, revise the Limitations, Normal Procedures, and Performance Sections and Appendix III of the FAA-approved Electra 188A or 188C Airplane Flight Manual (AFM), as applicable, to include the pages specified in Table 1 (for Model L-188A series airplanes), Table 2 (for Model L-188C series airplanes not equipped with Hamilton Standard propellers), or Table 3 (for Model L-188C series airplanes equipped with Hamilton Standard propellers) of this AD, as applicable.

   Table 1.--Revisions to the Electra 188A AFM for all Model L-188A Series Airplanes

   Section No.

   Section

   Page No.

   Date shown on page

   Preface............................... Log of Pages............. i

   March 10, 1998.

   Preface............................... Log of Pages............. ii

   March 10, 1998.

1. Limitations.............. 6

   December 1, 1997. 3..................................... Normal Procedures........ 10.1

   December 1, 1997. 3..................................... Normal Procedures........ 11

   March 10, 1998.

3. Normal Procedures........ 12

   December 1, 1997. 4..................................... Performance.............. A

   December 1, 1997. 4..................................... Performance.............. 6

   December 1, 1997. 4..................................... Performance.............. 8

   December 1, 1997. 4..................................... Performance.............. 12

   December 1, 1997.

   [[Page 43342]]

4. Performance.............. 12.1

   December 1, 1997. 4..................................... Performance.............. 12.2

   December 1, 1997. Appendix III.......................... Alt. Flap Data........... B

   December 1, 1997.

   Table 2.--Revisions to the Electra 188C AFM for Model L-188C Series Airplanes Not Equipped With Hamilton

   Standard Propellers

   Section No.

   Section

   Page No.

   Date shown on page

   Preface............................... Log of Pages............. i

   March 10, 1998.

   Preface............................... Log of Pages............. ii

   March 10, 1998.

1. Limitations.............. 6

   December 1, 1997. 3..................................... Normal Procedures........ 12.1

   December 1, 1997. 3..................................... Normal Procedures........ 13

   March 10, 1998.

3. Normal Procedures........ 14

   December 1, 1997. 4..................................... Performance.............. A

   December 1, 1997. 4..................................... Performance.............. 6

   December 1, 1997. 4..................................... Performance.............. 8

   December 1, 1997. 4..................................... Performance.............. 12

   December 1, 1997. 4..................................... Performance.............. 12.1

   December 1, 1997. 4..................................... Performance.............. 12.2

   December 1, 1997. Appendix III.......................... Alt. Flap Data........... B

   December 1, 1997.

   Table 3.--Revisions to the Electra 188C AFM for Model L-188C Series Airplanes Equipped With Hamilton Standard Propellers

   Section No.

   Section

   Page No.

   Date shown on page

   Preface............................... Log of Pages............. i

   March 10, 1998.

   Preface............................... Log of Pages............. ii

   March 10, 1998.

1. Limitations.............. 6

   December 1, 1997. 3..................................... Normal Procedures........ 12.1

   December 1, 1997. 3..................................... Normal Procedures........ 13

   March 10, 1998.

3. Normal Procedures........ 14

   December 1, 1997. A4.................................... Performance.............. A

   December 1, 1997. A4.................................... Performance.............. 6

   December 1, 1997. A4.................................... Performance.............. 8

   December 1, 1997. A4.................................... Performance.............. 12

   December 1, 1997. A4.................................... Performance.............. 12.1

   December 1, 1997. A4.................................... Performance.............. 12.2

   December 1, 1997. Appendix AIII......................... Alt. Flap Data........... B

   December 1, 1997.

   (b) An alternative method of compliance or adjustment of the compliance time that provides an acceptable level of safety may be used if approved by the Manager, Atlanta Aircraft Certification Office (ACO), FAA, Small Airplane Directorate. Operators shall submit their requests through an appropriate FAA Principal Operations Inspector, who may add comments and then send it to the Manager, Atlanta ACO.

   Note 2: Information concerning the existence of approved alternative method of compliance with this AD, if any, may be obtained from the Atlanta ACO.

   (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.

   Issued in Renton, Washington, on August 7, 1998. Darrell M. Pederson, Acting Manager, Transport Airplane Directorate, Aircraft Certification Service.

   [FR Doc. 98-21719Filed8-12-98; 8:45 am]

   BILLING CODE 4910-13-P