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[Federal Register Volume 76, Number 224 (Monday, November 21, 2011)]
[Rules and Regulations]
[Pages 71865-71867]
From the Federal Register Online via the Government Printing Office [www.gpo.gov]
[FR Doc No: 2011-29909]

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Rules and Regulations
                                                Federal Register
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This section of the FEDERAL REGISTER contains regulatory documents 
having general applicability and legal effect, most of which are keyed 
to and codified in the Code of Federal Regulations, which is published 
under 50 titles pursuant to 44 U.S.C. 1510.

The Code of Federal Regulations is sold by the Superintendent of Documents. 
Prices of new books are listed in the first FEDERAL REGISTER issue of each 
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Federal Register / Vol. 76, No. 224 / Monday, November 21, 2011 / 
Rules and Regulations

[[Page 71865]]

DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 25

[Docket No. FAA-2011-1280; Special Conditions No. 25-452-SC]

Special Conditions: Gulfstream Aerospace Corporation, Model GVI 
Airplane; Windshield Coating in Lieu of Wipers

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Final special conditions; request for comments.

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SUMMARY: This special condition is issued for the Gulfstream Aerospace 
Corporation Model GVI airplane. This airplane will have a novel or 
unusual design feature(s) associated with the use of a hydrophobic 
windshield coating, rather than windshield wipers, as the means to 
maintain a clear portion of the windshield during precipitation 
conditions, as required by the airworthiness standards for transport 
category airplanes. 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: The effective date of these special conditions is November 14, 
2011. We must receive your comments by January 5, 2012.

ADDRESSES: Send comments identified by docket number FAA-2011-1280 
using any of the following methods:
     Federal eRegulations Portal: Go to http://www.regulations.gov/ and follow the online instructions for sending 
your comments electronically.
     Mail: Send comments to Docket Operations, M-30, U.S. 
Department of Transportation (DOT), 1200 New Jersey Avenue SE., Room 
W12-140, West Building Ground Floor, Washington, DC 20590-0001.
     Hand Delivery or Courier: Take comments to Docket 
Operations in Room W12-140 of the West Building Ground Floor at 1200 
New Jersey Avenue SE., Washington, DC between 8 a.m. and 5 p.m., Monday 
through Friday, except federal holidays.
     Fax: Fax comments to Docket Operations at (202) 493-2251.
    Privacy: The FAA will post all comments it receives, without 
change, to http://www.regulations.gov/, including any personal 
information the commenter provides. Using the search function of the 
docket Web site, anyone can find and read the electronic form of all 
comments received into any FAA docket, including the name of the 
individual sending the comment (or signing the comment for an 
association, business, labor union, etc.). DOT's complete Privacy Act 
Statement can be found in the Federal Register published on April 11, 
2000 (65 FR 19477-19478), as well as at http://DocketsInfo.dot.gov/ gov/.
    Docket: Background documents or comments received may be read at 
http://www.regulations.gov/ at any time. Follow the online instructions 
for accessing the docket or go to the Docket Operations in Room W12-140 
of the West Building Ground Floor at 1200 New Jersey Avenue SE., 
Washington, DC between 9 a.m. and 5 p.m., Monday through Friday, except 
federal holidays.

FOR FURTHER INFORMATION CONTACT: Paul Bernado, Airplane and Flight Crew 
Interface Branch, ANM-111, Transport Airplane Directorate, Aircraft 
Certification Service, 1601 Lind Avenue SW., Renton, Washington 98057-
3356; telephone (425) 227-1209; facsimile (425) 227-1320.

SUPPLEMENTARY INFORMATION: The FAA has determined that notice of, and 
opportunity for prior public comment on, these special conditions are 
impracticable because these procedures would significantly delay 
issuance of the design approval and thus delivery of the affected 
aircraft. In addition, the substance of these special conditions has 
been subject to the public comment process in several prior instances 
with no substantive comments received. The FAA therefore finds that 
good cause exists for making these special conditions effective upon 
issuance.

Comments Invited

    We invite interested people to take part in this rulemaking by 
sending 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 
about these special conditions. You can inspect the docket 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 7:30 a.m. and 4 p.m., Monday through Friday, except federal 
holidays.
    We will consider all comments we receive by 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 us to acknowledge receipt of your comments on these 
special conditions, include with your comments a self-addressed, 
stamped postcard on which you have written the docket number. We will 
stamp the date on the postcard and mail it back to you.

Background

    On March 29, 2005, Gulfstream Aerospace Corporation (GAC) applied 
for an FAA type certificate for its new Model GVI passenger airplane 
(hereafter referred to as ``the GVI'' airplane). On September 28, 2006, 
GAC re-applied for the GVI type certificate in order to adhere to the 
application effectivity established by Title 14, Code of Federal 
Regulations (14 CFR) 21.17(c), and on July 31, 2011, GAC requested an 
extension of application in accordance with Sec.  21.17(d)(2). The FAA 
concurred with this request and established a new effective application 
date of September 18, 2007. The GVI airplane will be an all-new, two-
engine jet transport airplane. The maximum takeoff weight will be 
99,600 pounds, with a maximum passenger count of 19 passengers.

[[Page 71866]]

Type Certification Basis

    Under the provisions of 14 CFR 21.17, GAC must show that the GVI 
meets the applicable provisions of 14 CFR part 25, as amended by 
Amendments 25-1 through 25-120, 25-122, 25-124, and 25-132 thereto. 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 GVI because of a novel or unusual design feature, 
special conditions are prescribed under the provisions of Sec.  21.16.
    Special conditions are initially applicable to the model for which 
they are issued. Should the type certificate for that model be amended 
later to include any other model that incorporates the same novel or 
unusual design features, the special conditions would also apply to the 
other model.
    In addition to complying with the applicable airworthiness 
regulations and special conditions, the GVI 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. The FAA must also issue a 
finding of regulatory adequacy pursuant to section 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 GVI flightdeck design incorporates a hydrophobic windshield 
coating to provide adequate pilot compartment view in the presence of 
precipitation. Sole reliance on such a coating, without windshield 
wipers or a windshield blower, constitutes a novel or unusual design 
feature for which the applicable airworthiness regulations do not 
contain adequate or appropriate safety standards. Therefore, special 
conditions are required that provide the level of safety equivalent to 
that established by the regulations.

Discussion

    Section 25.773(b)(1) of 14 CFR 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 
precipitation in heavy rain at speeds up to 1.5 VSR1. The 
existing regulations cover technologies that primarily account for 
increased airflow and precipitation rates as limiting conditions. For 
example, as airflow and precipitation rates increase, the effectiveness 
of windshield wipers to maintain an area of clear vision normally 
degrades as airflow and precipitation rates increase. It is assumed 
that because high speeds and high precipitation rates represent 
limiting conditions for windshield wipers, they will also be effective 
at lower speeds and precipitation levels. Accordingly, Sec.  
25.773(b)(1)(i) does not require maintenance of a clear area of forward 
vision at lower speeds or lower precipitation rates. A forced air 
stream blown over the windshield has also been used to maintain an area 
of clear vision in precipitation. The limiting conditions for this 
technology are comparable to those for windshield wipers. Accordingly, 
introduction of this technology did not require special conditions to 
maintain the level of safety embodied in the existing regulations.
    However, the heavy rain and high-speed conditions specified in the 
current rule do not necessarily represent the limiting conditions for 
hydrophobic windshield coatings, which may depend to some degree on 
airflow over the windscreen to maintain a clear vision area. For 
example, in low-speed flight or during surface operations, airflow over 
the windshield may not be adequate to maintain a sufficiently clear 
area of the windshield. Additionally, during such critical times as 
during final approach where the airplane is at a higher-than-normal 
pitch attitude, airflow over the windshield may be disturbed. In these 
cases, areas of airflow disturbance or separation on the windshield 
could cause failure to maintain a clear vision area on the windshield.
    In addition to airflow, the effectiveness of hydrophobic coatings 
may also be affected by the size of precipitation. In some cases, the 
properties of the coating may not be sufficient to provide a clear area 
of vision during precipitation in the form of light mist.
    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.
    In summary, the current regulations identify speed and 
precipitation rate requirements that represent limiting conditions for 
windshield wipers and blowers, but not for hydrophobic coatings, so it 
is necessary to issue special conditions to maintain the level of 
safety represented by the current regulations.

Applicability

    As discussed above, these special conditions are applicable to the 
GVI. Should GAC apply at a later date for a change to the type 
certificate to include another model 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 GVI. It is not a rule of general applicability.
    The substance of these special conditions has been subjected to the 
notice and comment period in several prior instances and has been 
derived without substantive change from those previously issued. It is 
unlikely that prior public comment would result in a significant change 
from the substance contained herein. Therefore, because a delay would 
significantly affect the certification of the airplane, which is 
imminent, the FAA has determined that prior public notice and comment 
are unnecessary and impracticable, and good cause exists for adopting 
these special conditions upon issuance. The FAA is requesting comments 
to allow interested persons to submit views that may not have been 
submitted in response to the prior opportunities for comment described 
above.

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 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 GAC GVI airplanes.

[[Page 71867]]

Pilot Compartment View--Hydrophobic Coatings in Lieu of Windshield 
Wipers

    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 November 14, 2011.
Ali Bahrami,
Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 2011-29909 Filed 11-18-11; 8:45 am]
BILLING CODE 4910-13-P
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