[Federal Register: July 7, 2006 (Volume 71, Number 130)]
[Rules and Regulations]
[Page 38513-38515]
From the Federal Register Online via GPO Access [wais.access.gpo.gov]
[DOCID:fr07jy06-2]
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DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 25
[Docket No. NM340; Special Conditions No. 25-318-SC]
Special Conditions: Airbus Model A380-800 Airplane, Design Roll
Maneuver
AGENCY: Federal Aviation Administration (FAA), DOT.
ACTION: Final special conditions.
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SUMMARY: These special conditions are issued 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 for design roll
maneuvers. 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. Additional special conditions will be issued
for other novel or unusual design features of the Airbus Model A380-800
airplane.
DATES: Effective Date: The effective date of these special conditions
is June 29, 2006.
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:
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
[[Page 38514]]
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 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 is equipped with an electronic flight control system. In
this system, there is not a direct mechanical link between the airplane
flight control surface and the pilot's cockpit control device as there
is on more conventional airplanes. Instead, a flight control computer
commands the airplane flight control surfaces, based on input received
from the cockpit control device. The pilot input is modified by the
flight control computer--based on the current airplane flight
parameters before the command is given to the flight control surface.
Therefore, there is not a direct mechanical relationship between the
pilot command and the command given to the control surface.
The formulation of airplane design load conditions in 14 CFR part
25 is based on the assumption that the airplane is equipped with a
control system in which there is a direct mechanical linkage between
the pilot's cockpit control and the control surface. Thus for roll
maneuvers, the regulation specifies a displacement for the aileron
itself, and does not envision any modification of the pilot's control
input. Since such a system will affect the airplane flight loads and
thus the structural strength of the airplane, special conditions
appropriate for this type of control system are needed.
In particular, the special condition adjusts the design roll
maneuver requirements specified in Sec. 25.349(a), so that they take
into account the effect of the A380's electronic flight control
computer on the control surface deflection. The special condition
requires that the roll maneuver be performed by deflection of the
cockpit roll control, as opposed to specifying a deflection of the
aileron itself as the current regulation does. The deflection of the
control surface would then be determined from the cockpit input, based
on the computer's flight control laws and the current airplane flight
parameters.
Discussion of Comments
Notice of Proposed Special Conditions No. 25-06-01-SC, pertaining
to design roll maneuver for the Airbus A380 airplane, was published in
the Federal Register on March 29, 2006. A single comment which supports
the intent and language of the special conditions, as proposed, was
received from the Airline Pilots Association (ALPA). Accordingly, the
special conditions are adopted, as proposed.
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.
0
The authority citation for these special conditions is as follows:
Authority: 49 U.S.C. 106(g), 40113, 44701, 44702, 44704.
The Special Conditions
0
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 the Airbus A380-800 airplane.
In lieu of compliance with 14 CFR 25.349(a), the following special
condition applies:
The following conditions, speeds, and cockpit roll control motions
(except as the motions may be limited by pilot effort) must be
considered in combination with an airplane load factor of zero and two-
thirds of the positive maneuvering factor used in design. In
determining the resulting control surface deflections, the torsional
flexibility of the wing must be considered in accordance with Sec.
25.301(b):
a. Conditions corresponding to steady rolling velocities must be
investigated. In addition, conditions corresponding to maximum angular
acceleration must be investigated for airplanes with engines
[[Page 38515]]
or other weight concentrations outboard of the fuselage. For the
angular acceleration conditions, zero rolling velocity may be assumed
in the absence of a rational time history investigation of the
maneuver.
b. At VA, sudden movement of the cockpit roll control up
to the limit is assumed. The position of the cockpit roll control must
be maintained, until a steady roll rate is achieved and then must be
returned suddenly to the neutral position.
c. At VC, the cockpit roll control must be moved
suddenly and maintained so as to achieve a roll rate not less than that
obtained in paragraph b. above.
d. At VD, the cockpit roll control must be moved
suddenly and maintained so as to achieve a roll rate not less than one
third of that obtained in paragraph b. above.
Issued in Renton, Washington, on June 29, 2006.
Ali Bahrami,
Manager, Transport Airplane Directorate, Aircraft Certification
Service.
[FR Doc. E6-10673 Filed 7-6-06; 8:45 am]
BILLING CODE 4910-13-P