Special Conditions: Airbus Model A380-800 Airplane, Airplane Jacking Loads, 15350-15351 [E6-4494]

Agencies

• Federal Aviation Administration
• DEPARTMENT OF TRANSPORTATION

[Federal Register Volume 71, Number 59 (Tuesday, March 28, 2006)]
[Proposed Rules]
[Pages 15350-15351]
From the Federal Register Online via the Government Printing Office [www.gpo.gov]
[FR Doc No: E6-4494]


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

DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 25

[Docket No. NM343; Notice No. 25-06-04-SC]


Special Conditions: Airbus Model A380-800 Airplane, Airplane 
Jacking Loads

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Notice of proposed special conditions.

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

SUMMARY: This notice proposes special conditions for the Airbus A380-
800 airplane. This airplane will have novel or unusual design features 
when compared to the state of technology envisioned in the 
airworthiness standards for transport category airplanes. Many of these 
novel or unusual design features are associated with the complex 
systems and the configuration of the airplane, including its full-
length double deck. For these design features, the applicable 
airworthiness regulations do not contain adequate or appropriate safety 
standards regarding airplane jacking loads. 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. 
Additional special conditions will be issued for other novel or unusual 
design features of the Airbus Model A380-800 airplane.

DATES: Comments must be received on or before May 12, 2006.

ADDRESSES: Comments on this proposal may be mailed in duplicate to: 
Federal Aviation Administration, Transport Airplane Directorate, 
Attention: Rules Docket (ANM-113), Docket No. NM343, 1601 Lind Avenue 
SW., Renton, Washington 98055-4056; or delivered in duplicate to the 
Transport Airplane Directorate at the above address. All comments must 
be marked: Docket No. NM343. 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: Holly Thorson, FAA, International 
Branch, ANM-116, Transport Airplane Directorate, Aircraft Certification 
Service, 1601 Lind Avenue SW., Renton, Washington 98055-4056; telephone 
(425) 227-1357; 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 proposed 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 notice between 7:30 a.m. and 4 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 the 
proposed special conditions in light of the comments we receive.
    If you want the FAA to acknowledge receipt of your comments on this 
proposal, include with your comments a pre-addressed, stamped postcard 
on which the docket number appears. We will stamp the date on the 
postcard and mail it back to you.

Background

    Airbus applied for FAA certification/validation of the 
provisionally-designated Model A3XX-100 in its letter AI/L 810.0223/98, 
dated August 12, 1998, to the FAA. Application for certification by the 
Joint Aviation Authorities (JAA) of Europe had been made on January 16, 
1998, reference AI/L 810.0019/98. In its letter to the FAA, Airbus 
requested an extension to the 5-year period for type certification in 
accordance with 14 CFR 21.17(c). The request was for an extension to a 
7-year period, using the date of the initial application letter to the 
JAA as the reference date. The reason given by Airbus for the request 
for extension is related to the technical challenges, complexity, and 
the number of new and novel features on the airplane. On November 12, 
1998, the Manager, Aircraft Engineering Division, AIR-100, granted 
Airbus' request for the 7-year period, based on the date of application 
to the JAA.
    In its letter AI/LE-A 828.0040/99 Issue 3, dated July 20, 2001, 
Airbus stated that its target date for type certification of the Model 
A380-800 had been moved from May 2005, to January 2006, to match the 
delivery date of the first production airplane. In a subsequent letter 
(AI/L 810.0223/98 issue 3, dated January 27, 2006), Airbus stated that 
its target date for type certification is October 2, 2006. In 
accordance with 14 CFR 21.17(d)(2), Airbus chose a new application date 
of December 20, 1999, and requested that the 7-year certification 
period which had already been approved be continued. The FAA has 
reviewed the part 25 certification basis for the Model A380-800 
airplane, and no changes are required based on the new application 
date.
    The Model A380-800 airplane will be an all-new, four-engine jet 
transport airplane with a full double-deck, two-aisle cabin. The 
maximum takeoff weight will be 1.235 million pounds with a typical 
three-class layout of 555 passengers.

Type Certification Basis

    Under the provisions of 14 CFR 21.17, Airbus must show that the 
Model A380-800 airplane meets the applicable provisions of 14 CFR part 
25, as amended by Amendments 25-1 through 25-98. If the Administrator 
finds that the applicable airworthiness regulations do not contain 
adequate or appropriate safety standards for the Airbus A380-800 
airplane because of novel or unusual design features, special 
conditions are prescribed under the provisions of 14 CFR 21.16.
    In addition to the applicable airworthiness regulations and special 
conditions, the Airbus Model A380-800 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. In addition, the 
FAA must issue a finding of regulatory adequacy pursuant to section 611 
of Public Law

[[Page 15351]]

93-574, the ``Noise Control Act of 1972.''
    Special conditions, as defined in 14 CFR 11.19, are issued in 
accordance with 14 CFR 11.38 and become part of the type certification 
basis in accordance with 14 CFR 21.17(a)(2).
    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 feature, the special conditions would also apply to the 
other model under the provisions of 14 CFR 21.101.

Discussion of Novel or Unusual Design Features

    The A380 has a multi-leg landing gear arrangement consisting of a 
nose gear, two wing mounted gear, and two body mounted gear. This 
arrangement is different from the simpler, conventional landing gear 
arrangement envisioned by the jacking load requirements of 14 CFR 
25.519. Those regulations assume a landing gear arrangement comprising 
a three point suspension system (two main gear and a nose or tail gear) 
in which load sharing between the landing gear can be determined 
without considering the flexibility of the airframe.
    For a five point suspension system, like that of the A380, 
calculations that consider airplane flexibilities are necessary to 
determine load sharing between landing gear units accurately. (The 
flexibility of the individual landing gear oleos and of the airplane 
itself affect how the weight of the airplane is distributed among the 
individual landing gear units.)
    Special conditions are necessary to allow a rational analysis of 
the jacking condition for the main and body landing gear. (This 
analysis will include the case of bogie gears where one leg of a bogie 
is jacked and the other leg is supported on a tripod--which is not 
addressed by Sec.  25.519.) The applicant has proposed a rational 
jacking analysis, which makes reasonable or conservative assumptions 
about the runway configuration and ground wind speeds.

Applicability

    As discussed above, these special conditions are applicable to the 
Airbus A380-800 airplane. Should Airbus apply at a later date for a 
change to the type certificate to include another model incorporating 
the same novel or unusual design features, these special conditions 
would apply to that model as well under the provisions of Sec.  21.101.

Conclusion

    This action affects only certain novel or unusual design features 
of the Airbus A380-800 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, pursuant to the authority delegated to me by the 
Administrator, the Federal Aviation Administration (FAA) proposes the 
following special conditions as part of the type certification basis 
for the Airbus A380-800 airplane.

Part I

    In lieu of compliance with 14 CFR 25.519(b)(1), for jacking by the 
landing gear at the maximum ramp weight of the airplane, the airplane 
structure maybe designed to withstand the maximum limit loads arising 
from conditions a. and b. below.
    a. The loads arising from jacking by the landing gear may be 
derived from a rational analysis under both of the following 
conditions:
    1. A ramp crown defined by a 1.5% gradient, the crest of the 
gradient to be in the most adverse position for the loading of the 
undercarriage unit in question; and the maximum allowable steady wind 
for jacking operations from any horizontal direction; and the most 
adverse combination of oleo leg pressures within service tolerances; 
and jack(s) at the maximum possible overshoot.
    2. A ramp crown defined by a 1.5% gradient, the crest of the 
gradient to be in the most adverse position for the loading of the 
undercarriage unit in question; and twice the maximum allowable steady 
wind for jacking operations from any horizontal direction; and a 
nominal distribution of oleo leg pressures; and jacking performed in 
accordance with recommended procedures.
    b. The limit horizontal load at the jacking point undercarriage 
unit may not be less than the higher of that derived from the above 
rational analysis or 0.33 times the limit static vertical reaction 
found with the undercarriage unit in question supported at the jacking 
points with the aircraft in the unjacked position. This load must be 
applied in combination with the vertical loads arising from the 
analysis of (a) above.

Part II

    Jacking equipment used for the airplane jacking operation must be 
controlled by a specification that assures that jacking operations are 
conducted in a manner that is consistent with the provisions of this 
special condition. Jacking instructions must be developed and 
incorporated in the Instructions for Continued Airworthiness to assure 
that the proper jacking equipment is used and that the jacking 
operation is conducted in a manner consistent with the provisions of 
this special condition. The jacking instructions may be by means of 
placards conspicuously located near the jacking points or by other 
suitable means acceptable to the Administrator.

    Issued in Renton, Washington, on March 20, 2006.
Ali Bahrami,
Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. E6-4494 Filed 3-27-06; 8:45 am]
BILLING CODE 4910-13-P