Document ID: FAA-2019-0204-0001
Agency: faa
Document Type: Proposed Rule
Title: Airworthiness Directives: Learjet Inc. Airplanes
Posted Date: 2019-05-13T04:00Z

[Federal Register Volume 84, Number 92 (Monday, May 13, 2019)]
[Proposed Rules]
[Pages 20823-20825]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2019-09689]

-----------------------------------------------------------------------

DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2019-0204; Product Identifier 2018-CE-042-AD]
RIN 2120-AA64

Airworthiness Directives; Learjet Inc. Airplanes

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Notice of proposed rulemaking (NPRM).

-----------------------------------------------------------------------

SUMMARY: We propose to adopt a new airworthiness directive (AD) for 
certain Learjet Inc. Model 60 airplanes. This proposed AD was prompted 
by a report of a reverse thrust command accelerating the airplane 
instead of decelerating the airplane. The acceleration with reverse 
thrust commanded occurred when the thrust reverser doors were in the 
stowed position instead of the deployed position. This proposed AD 
would require installing a Thrust Reverser (T/R) Voice Command Warning 
System (VCWS) to alert the crew of a T/R malfunction. We are proposing 
this AD to address the unsafe condition on these products.

DATES: We must receive comments on this proposed AD by June 27, 2019.

ADDRESSES: You may send comments, using the procedures found in 14 CFR 
11.43 and 11.45, by any of the following methods:
     Federal eRulemaking Portal: Go to http://www.regulations.gov. Follow the instructions for submitting comments.
     Fax: 202-493-2251.
     Mail: U.S. Department of Transportation, Docket 
Operations, M-30, West Building Ground Floor, Room W12-140, 1200 New 
Jersey Avenue SE, Washington, DC 20590.
     Hand Delivery: Deliver to Mail address above between 9 
a.m. and 5 p.m., Monday through Friday, except Federal holidays.
    For service information identified in this NPRM, contact Learjet 
Inc., MS 53, P.O. Box 7707, Wichita, Kansas 67277-7707; telephone: 
(toll free) 1-866-538-1247; (514) 855-2999; internet: https://my.businessaircraft.bombardier.com. You may view this service 
information at the FAA, Policy and Innovation Division, 901 Locust, 
Kansas City, Missouri 64106. For information on the availability of 
this material at the FAA, call (816) 329-4148.

Examining the AD Docket

    You may examine the AD docket on the internet at http://www.regulations.gov by searching for and locating Docket No. FAA-2019-
0204; or in person at Docket Operations between 9 a.m. and 5 p.m., 
Monday through Friday, except Federal holidays. The AD docket contains 
this NPRM, the regulatory evaluation, any comments received, and other 
information. The street address for Docket Operations (phone: 800-647-
5527) is listed above. Comments will be available in the AD docket 
shortly after receipt.

FOR FURTHER INFORMATION CONTACT: James Galstad, Aerospace Engineer, 
Wichita ACO Branch, 1801 Airport Road, Room 100, Wichita, Kansas 67209; 
telephone: (316) 946-4135; fax: (316) 946-4107; email: 
james.galstad@faa.gov or eabd838982839e8bc7a9a5b9aa8c8b8bc48d859c.

SUPPLEMENTARY INFORMATION:

Comments Invited

    We invite you to send any written relevant data, views, or 
arguments about this proposal. Send your comments to an address listed 
under the ADDRESSES section. Include ``Docket No. FAA-2019-0204; 
Product Identifier 2018-CE-042-AD'' at the beginning of your comments. 
We specifically invite comments on the overall regulatory, economic, 
environmental, and energy aspects of this NPRM. We will consider all 
comments received by the closing date and may amend this NPRM because 
of those comments.
    We will post all comments we receive, without change, to http://www.regulations.gov, including any personal information you provide. We 
will also post a report summarizing each substantive verbal contact we 
receive about this NPRM.

Discussion

    We received a report of a high-speed rejected takeoff involving a 
Learjet Model 60 airplane that occurred when all four main landing gear 
(MLG) tires blew out during the takeoff roll. The tires blew out due to 
internal heat damage consistent with under-inflation, overloading, or a 
combination of both. Subsequently, damage from tires caused damage to 
various components,

[[Page 20824]]

including the MLG squat switches, brake hydraulic tubes, wheel speed 
sensor wiring, and anti-skid components. In the event of squat switch 
wiring failures, thrust reverser operation can be adversely affected. 
During the subject accident, forward thrust occurred when the thrust 
reverser doors stowed due to the failure, and at the same time the crew 
was still commanding reverse thrust. Squat switch wiring can also be 
damaged by other external factors, such as bird strikes or deer 
strikes.
    We consider this NPRM to be the third of three ADs that are related 
to each other, and collectively address unsafe conditions that might 
result from damage to critical components on the landing gear or in the 
wheel well that affect the braking, spoiler, and thrust reverser 
systems. AD 2010-11-11, Amendment 39-16316 (75 FR 32255, June 8, 2010), 
was issued to prevent tire failure, and AD 2013-13-09, Amendment 39-
17497 (78 FR 39574, July 2, 2013), was issued to prevent failure of the 
braking system or adverse operation of the spoiler and reverse thruster 
system due to external damage, particularly from tire failure, which 
could result in loss of control of the airplane. This proposed AD would 
require installing a T/R VCWS to alert the crew of a T/R malfunction. 
We are proposing this AD to mitigate failure of the engine thrust 
reverser system.
    This condition, if not addressed, could result in the airplane 
overrunning the runway or a runway excursion.

Related Service Information Under 1 CFR Part 51

    We reviewed Bombardier Learjet 60 Service Bulletin SB 60-78-9, 
dated June 25, 2018. The service bulletin contains procedures for 
installing a T/R VCWS to alert the pilot of a T/R malfunction. This 
service information is reasonably available because the interested 
parties have access to it through their normal course of business or by 
the means identified in the ADDRESSES section.

FAA's Determination

    We are proposing this AD because we evaluated all the relevant 
information and determined the unsafe condition described previously is 
likely to exist or develop in other products of the same type design.

Proposed AD Requirements

    This proposed AD would require installing the T/R VCWS.

Costs of Compliance

    We estimate that this proposed AD affects 289 airplanes of U.S. 
registry.
    We estimate the following costs to comply with this proposed AD:

                                                 Estimated costs
----------------------------------------------------------------------------------------------------------------
                                                                                     Cost per      Cost on U.S.
                Action                         Labor cost           Parts cost        product        operators
----------------------------------------------------------------------------------------------------------------
Install a T/R VCWS....................  20 work-hours x $85 per          $28,274         $29,974      $8,662,486
                                         hour = $1,700.
----------------------------------------------------------------------------------------------------------------

    According to the manufacturer, some of the costs of this proposed 
AD may be covered under warranty, thereby reducing the cost impact on 
affected individuals. We do not control warranty coverage for affected 
individuals. As a result, we have included all costs in our cost 
estimate.

Authority for This Rulemaking

    Title 49 of the United States Code specifies the FAA's authority to 
issue rules on aviation safety. Subtitle I, section 106, describes the 
authority of the FAA Administrator. Subtitle VII: Aviation Programs, 
describes in more detail the scope of the Agency's authority.
    We are issuing this rulemaking under the authority described in 
Subtitle VII, Part A, Subpart III, section 44701: ``General 
requirements.'' Under that section, Congress charges the FAA with 
promoting safe flight of civil aircraft in air commerce by prescribing 
regulations for practices, methods, and procedures the Administrator 
finds necessary for safety in air commerce. This regulation is within 
the scope of that authority because it addresses an unsafe condition 
that is likely to exist or develop on products identified in this 
rulemaking action.
    This AD is issued in accordance with authority delegated by the 
Executive Director, Aircraft Certification Service, as authorized by 
FAA Order 8000.51C. In accordance with that order, issuance of ADs is 
normally a function of the Compliance and Airworthiness Division, but 
during this transition period, the Executive Director has delegated the 
authority to issue ADs applicable to small airplanes, gliders, 
balloons, airships, domestic business jet transport airplanes, and 
associated appliances to the Director of the Policy and Innovation 
Division.

Regulatory Findings

    We determined that this proposed AD would not have federalism 
implications under Executive Order 13132. This proposed AD would 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.
    For the reasons discussed above, I certify 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),
    (3) Will not affect intrastate aviation in Alaska, and
    (4) 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.

List of Subjects in 14 CFR Part 39

    Air transportation, Aircraft, Aviation safety, Incorporation by 
reference, Safety.

The Proposed Amendment

    Accordingly, under the authority delegated to me by the 
Administrator, the FAA proposes to amend 14 CFR part 39 as follows:

PART 39--AIRWORTHINESS DIRECTIVES

0
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]

0
2. The FAA amends Sec.  39.13 by adding the following new airworthiness 
directive (AD):

Learjet Inc.: Docket No. FAA-2019-0204; Product Identifier 2018-CE-
042-AD.

(a) Comments Due Date

    We must receive comments by June 27, 2019.

(b) Affected ADs

    None.

[[Page 20825]]

(c) Applicability

    This AD applies to Learjet Inc. Model 60 airplanes, serial 
numbers 60-001 through 60-430, certificated in any category.

(d) Subject

    Joint Aircraft System Component (JASC)/Air Transport Association 
(ATA) of America Code 78, Engine Exhaust.

(e) Unsafe Condition

    This AD was prompted by a report of a reverse thrust command 
accelerating the airplane instead of decelerating the airplane 
because the engine thrust reverser doors were stowed instead of 
deployed. We are issuing this AD to mitigate failure of the engine 
thrust reverser system. The unsafe condition, if not addressed, 
could result in the airplane overrunning the runway or a runway 
excursion.

(f) Compliance

    Comply with this AD within the compliance times specified, 
unless already done.

(g) Install a Thrust Reverser Voice Command Warning System

    Within the next 1,200 hours time-in-service or within the next 
48 months after the effective date of this AD, whichever occurs 
first, install a Thrust Reverser Voice Command Warning System and 
perform a functional test in accordance with sections 3.A. through 
3.C. of the Accomplishment Instructions in Bombardier Learjet 60 
Service Bulletin SB 60-78-9, dated June 25, 2018.

(h) Alternative Methods of Compliance (AMOCs)

    (1) The Manager, Wichita ACO Branch, FAA, has the authority to 
approve AMOCs for this AD, if requested using the procedures found 
in 14 CFR 39.19. In accordance with 14 CFR 39.19, send your request 
to your principal inspector or local Flight Standards District 
Office, as appropriate. If sending information directly to the 
manager of the certification office, send it to the attention of the 
person identified in paragraph (i) of this AD.
    (2) Before using any approved AMOC, notify your appropriate 
principal inspector, or lacking a principal inspector, the manager 
of the local flight standards district office/certificate holding 
district office.

(i) Related Information

    (1) For more information about this AD, contact James Galstad, 
Aerospace Engineer, Wichita ACO Branch, 1801 Airport Road, Room 100, 
Wichita, Kansas 67209; telephone: (316) 946-4135; fax: (316) 946-
4107; email: james.galstad@faa.gov or 7d2a141e1514091c503e322e3d1b1c1c531a120b.
    (2) For service information identified in this AD, contact 
Learjet Inc., MS 53, P.O. Box 7707, Wichita, Kansas 67277-7707; 
telephone: (toll free) 1-866-538-1247; (514) 855-2999; internet: 
https://my.businessaircraft.bombardier.com. You may view this 
service information at the FAA, Policy and Innovation Division, 901 
Locust, Kansas City, Missouri 64106. For information on the 
availability of this material at the FAA, call (816) 329-4148.

    Issued in Kansas City, Missouri, on May 3, 2019.
Melvin J. Johnson,
Aircraft Certification Service, Deputy Director, Policy and Innovation 
Division, AIR-601.
[FR Doc. 2019-09689 Filed 5-10-19; 8:45 am]
 BILLING CODE 4910-13-P