5990 Federal Register / Vol. 77, No. 25 / Tuesday, February 7, 2012 / Rules and Regulations 

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, PilotCompartment 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 airworthiness standards. 

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 

(425) 227–1149. 

SUPPLEMENTARY INFORMATION: 

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 

§ 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 § 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 § 11.38, and they become part of 

the type-certification basis under 

§ 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 

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 the 

windshield. 

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. 

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 

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: 49 106(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 typecertification 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 January 

30, 2012. 

K.C. Yanamura, 

Acting Manager, Transport Airplane 

Directorate, Aircraft Certification Service. 

[FR Doc. 2012–2672 Filed 2–6–12; 8:45 am] 

BILLING CODE 4910–13–P 


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