[Federal Register Volume 77, Number 25 (Tuesday, February 7, 2012)]
[Rules and Regulations]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2012-2672]
DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 25
[Docket No. FAA-2011-1108; Special Conditions No. 25-456-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: Final special conditions.
SUMMARY: These special conditions are issued 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 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
DATES: Effective Date: March 8, 2012.
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
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
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 part 34, and the noise-
certification requirements of 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.
Section 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
Discussion of Comments
Notice of proposed special conditions no. 25-11-16-SC for the
Learjet Model LJ-200-1A10 airplane was published in the Federal
Register on October 14, 2011 (76 FR 63851). No comments were received,
and the special conditions are adopted as proposed.
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
conditions would apply to that model as well.
This action affects only certain novel or unusual design features
on the Model LJ-200-1A10 airplane. It is not a rule of general
List of Subjects in 14 CFR Part 25
Aircraft, Aviation safety, Reporting and recordkeeping
The authority citation for these special conditions is as follows:
Authority: 49 106(g), 40113, 44701, 44702, 44704.
The Special Conditions
Accordingly, pursuant to the authority delegated to me by the
Administrator, the following special conditions are issued as part of
the type-certification basis for Learjet Inc. Model LJ-200-1A10
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 January 30, 2012.
Acting Manager, Transport Airplane Directorate, Aircraft Certification
[FR Doc. 2012-2672 Filed 2-6-12; 8:45 am]
BILLING CODE 4910-13-P