[Federal Register Volume 63, Number 156 (Thursday, August 13, 1998)]
[Proposed Rules]
[Pages 43340-43342]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 98-21719]


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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).

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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 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 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               
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              Section No.                        Section                 Page No.          Date shown on page   
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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.       
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    Table 2.--Revisions to the Electra 188C AFM for Model L-188C Series Airplanes Not Equipped With Hamilton    
                                               Standard Propellers                                              
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              Section No.                        Section                 Page No.          Date shown on page   
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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.       
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  Table 3.--Revisions to the Electra 188C AFM for Model L-188C Series Airplanes Equipped With Hamilton Standard 
                                                   Propellers                                                   
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              Section No.                        Section                 Page No.          Date shown on page   
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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.       
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    (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. 98-21719 Filed 8-12-98; 8:45 am]
BILLING CODE 4910-13-P