[Federal Register Volume 76, Number 199 (Friday, October 14, 2011)]
[Proposed Rules]
[Pages 63851-63852]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2011-26555]



[[Page 63851]]

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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 25

[Docket No. FAA-2011-1108; Notice No. 25-11-16-SC]


Special Conditions: Learjet Inc., Model LJ-200-1A10 Airplane, 
Pilot-Compartment View Through Hydrophobic Windshield Coatings In Lieu 
of Windshield Wipers

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Notice of proposed special conditions.

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SUMMARY: This action proposes special conditions for the Learjet Model 
LJ-200-1A10 airplane. This airplane will have a novel or unusual design 
feature associated with hydrophobic windshield coatings in lieu of 
windshield wipers. The applicable airworthiness regulations do not 
contain adequate or appropriate safety standards for this design 
feature. These proposed special conditions contain the additional 
safety standards that the Administrator considers necessary to 
establish a level of safety equivalent to that established by the 
existing airworthiness standards.

DATES: Comments must be received on or before November 28, 2011.

ADDRESSES: Comments on this proposal may be mailed in duplicate to: 
Federal Aviation Administration, Transport Airplane Directorate, Attn: 
Rules Docket (ANM-113), Docket No. FAA-2011-1108, 1601 Lind Avenue, 
SW., Renton, Washington, 98057-3356; or delivered in duplicate to the 
Transport Airplane Directorate at the above address. Comments must be 
marked: Docket No. FAA-2011-1108. Comments may be inspected in the 
Rules Docket weekdays, except Federal holidays, between 7:30 a.m. and 4 
p.m.

FOR FURTHER INFORMATION CONTACT: Paul Bernado, Transport Airplane 
Directorate, Aircraft Certification Service, 1601 Lind Avenue, SW., 
Renton, Washington, 98057-3356; telephone (425) 227-1209; facsimile 
(425) 227-1149.

SUPPLEMENTARY INFORMATION:

Comments Invited

    The FAA invites interested persons to participate in this 
rulemaking by submitting written comments, data, or views. The most 
helpful comments reference a specific portion of the special 
conditions, explain the reason for any recommended change, and include 
supporting data. We ask that you send us two copies of written 
comments.
    We will file in the docket all comments we receive, as well as a 
report summarizing each substantive public contact with FAA personnel 
concerning these special conditions. The docket is available for public 
inspection before and after the comment closing date. If you wish to 
review the docket in person, go to the address in the ADDRESSES section 
of this preamble between 9 a.m. and 5 p.m., Monday through Friday, 
except Federal holidays.
    We will consider all comments we receive on or before the closing 
date for comments. We will consider comments filed late if it is 
possible to do so without incurring expense or delay. We may change 
these special conditions based on the comments we receive.
    If you want the FAA to acknowledge receipt of your comments on this 
proposal, include with your comments a self-addressed, stamped postcard 
on which the docket number appears. We will stamp the date on the 
postcard and mail it back to you.

Background

    On January 11, 2008, Learjet Inc. applied for a type certificate 
for a new Model LJ-200-1A10 airplane. This airplane is 68 feet long 
with a 65-foot wing span and accommodates up to 10 passengers. The LJ-
200-1A10 airplane uses a hydrophobic windshield coating, in lieu of 
windshield wipers, for an unobstructed outside view from the pilot 
compartment.

Type Certification Basis

    Under the provisions of Title 14, Code of Federal Regulations (14 
CFR) 21.17, Learjet Inc. must show that the Model LJ-200-1A10 airplane 
meets the applicable provisions of part 25, as amended by Amendments 
25-1 through 25-123.
    If the Administrator finds that the applicable airworthiness 
regulations (i.e., 14 CFR part 25) do not contain adequate or 
appropriate safety standards for the Model LJ-200-1A10 airplane because 
of a novel or unusual design feature, special conditions are prescribed 
under the provisions of Sec.  21.16.
    In addition to the applicable airworthiness regulations and special 
conditions, the Model LJ-200-1A10 airplane must comply with the fuel-
vent and exhaust-emission requirements of 14 CFR part 34, and the 
noise-certification requirements of 14 CFR part 36, and the FAA must 
issue a finding of regulatory adequacy pursuant to Sec.  611 of Public 
Law 92-574, the ``Noise Control Act of 1972.''
    The FAA issues special conditions, as defined in 14 CFR 11.19, in 
accordance with Sec.  11.38, and they become part of the type-
certification basis under Sec.  21.17(a)(2).

Novel or Unusual Design Features

    The Learjet Model LJ-200-1A10 airplane will incorporate the 
following novel or unusual design features:
    The Model LJ-200-1A10 airplane flight deck design incorporates a 
hydrophobic windshield coating to provide, during precipitation, an 
adequate outside view from the pilot compartment. Sole reliance on such 
a coating, without windshield wipers, constitutes a novel or unusual 
design feature for which the applicable airworthiness regulations do 
not contain adequate or appropriate safety standards. Therefore, a 
special condition is required to provide a level of safety equivalent 
to that established by the regulations.

Discussion

    14 CFR 25.773(b)(1) requires a means to maintain a clear portion of 
the windshield for both pilots to have a sufficiently extensive view 
along the flight path during precipitation conditions. The regulations 
require this means to maintain such an area during heavy-rain 
precipitation at airplane speeds up to 1.5 VSR1. Hydrophobic 
windshield coatings may depend to some degree on airflow to maintain a 
clear-vision area. The heavy rain and high speed conditions specified 
in the current rule do not necessarily represent the limiting condition 
for this new technology. For example, airflow over the windshield, 
which may be necessary to remove moisture from the windshield, may not 
be adequate to maintain a sufficiently clear area of the windshield in 
low-speed flight or during surface operations. Alternatively, airflow 
over the windshield may be disturbed during such critical times as the 
approach to land, where the airplane is at a higher-than-normal pitch 
attitude. In these cases, areas of airflow disturbance or separation on 
the windshield could cause failure to maintain a clear-vision area on 
the windshield.

Applicability

    As discussed above, these special conditions are applicable to the 
Model LJ-200-1A10 airplane. Should Learjet Inc. apply at a later date 
for a change to the type certificate to include other type designs 
incorporating the same novel or unusual design feature, the special

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conditions would apply to that model as well.

Conclusion

    This action affects only certain novel or unusual design features 
on the Model LJ-200-1A10 airplane. It is not a rule of general 
applicability.

List of Subjects in 14 CFR Part 25

    Aircraft, Aviation safety, Reporting and recordkeeping 
requirements.

    The authority citation for these special conditions is as follows:

    Authority: 49 U.S.C. 106(g), 40113, 44701, 44702, 44704.

The Proposed Special Conditions

    Accordingly, the Federal Aviation Administration (FAA) proposes the 
following special conditions as part of the type-certification basis 
for Learjet Inc. Model LJ-200-1A10 airplanes.
    The airplane must have a means to maintain a clear portion of the 
windshield, during precipitation conditions, enough for both pilots to 
have a sufficiently extensive view along the ground or flight path in 
normal taxi and flight attitudes of the airplane. This means must be 
designed to function, without continuous attention on the part of the 
crew, in conditions from light misting precipitation to heavy rain, at 
speeds from fully stopped in still air, to 1.5 VSR1 with 
lift and drag devices retracted.

    Issued in Renton, Washington, on October 6, 2011.
Ali Bahrami,
Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 2011-26555 Filed 10-13-11; 8:45 am]
BILLING CODE 4910-13-P