[Federal Register: October 16, 2007 (Volume 72, Number 199)]
[Proposed Rules]
[Page 58560-58561]
From the Federal Register Online via GPO Access [wais.access.gpo.gov]
[DOCID:fr16oc07-23]
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Proposed Rules
Federal Register
________________________________________________________________________
This section of the FEDERAL REGISTER contains notices to the public of
the proposed issuance of rules and regulations. The purpose of these
notices is to give interested persons an opportunity to participate in
the rule making prior to the adoption of the final rules.
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[[Page 58560]]
DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 25
[Docket No. NM378 Special Conditions No. 25-07-11-SC]
Special Conditions: Boeing Model 787-8 Airplane; Operation
Without Normal Electrical Power
AGENCY: Federal Aviation Administration (FAA), DOT.
ACTION: Notice of proposed special conditions.
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SUMMARY: This notice proposes special conditions for the Boeing Model
787-8 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. The Boeing
Model 787-8 airplane will have numerous electrically operated systems
whose function is needed for continued safe flight and landing of the
airplane. The applicable airworthiness regulations do not contain
adequate or appropriate safety standards for these design features.
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 Boeing Model 787-8
airplanes.
DATES: Comments must be received on or before November 15, 2007.
ADDRESSES: Comments on this proposal may be mailed in duplicate to:
Federal Aviation Administration, Transport Airplane Directorate,
Attention: Rules Docket (ANM-113), Docket No. NM378, 1601 Lind Avenue,
SW., Renton, Washington 98057-3356; or delivered in duplicate to the
Transport Airplane Directorate at the above address. All comments must
be marked Docket No. NM378. 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: Stephen Slotte, FAA, Airplane & Flight
Crew Interface Branch, ANM-111, Transport Airplane Directorate,
Aircraft Certification Service, 1601 Lind Avenue, SW., Renton,
Washington 98057-3356; telephone (425) 227-2315; facsimile (425) 227-
1320.
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 based on 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
On March 28, 2003, Boeing applied for an FAA type certificate for
its new Boeing Model 787-8 passenger airplane. The Boeing Model 787-8
airplane will be an all-new, two-engine jet transport airplane with a
two-aisle cabin. The maximum takeoff weight will be 476,000 pounds,
with a maximum passenger count of 381 passengers.
Type Certification Basis
Under provisions of Title 14 Code of Federal Regulations (CFR)
21.17, Boeing must show that Boeing Model 787-8 airplanes (hereafter
referred to as ``the 787'') meet the applicable provisions of 14 CFR
part 25, as amended by Amendments 25-1 through 25-117, except
Sec. Sec. 25.809(a) and 25.812, which will remain at Amendment 25-115.
If the Administrator finds that the applicable airworthiness
regulations do not contain adequate or appropriate safety standards for
the 787 because of a novel or unusual design feature, special
conditions are prescribed under provisions of 14 CFR 21.16.
In addition to the applicable airworthiness regulations and special
conditions, the 787 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 92-574, the
``Noise Control Act of 1972.''
Special conditions, as defined in 14 CFR 11.19, are issued in
accordance with Sec. 11.38 and become part of the type certification
basis in accordance with Sec. 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 or similar
novel or unusual design feature, the special conditions would also
apply to the other model under the provisions of Sec. 21.101.
Novel or Unusual Design Features
The 787 will incorporate a number of novel or unusual design
features, some of which have not been previously installed on large
commercial aircraft. Because of these design features, these proposed
special conditions differ from similar previously proposed special
conditions for other airplane models. Due to rapid improvements in
airplane technology, the applicable airworthiness regulations do not
contain adequate or appropriate safety standards for these design
features. These proposed special conditions for the 787 contain the
additional safety standards that the Administrator considers necessary
to establish a level of safety equivalent to
[[Page 58561]]
that established by the existing airworthiness standards.
In addition to an electronic flight control system, a number of
systems that have traditionally been pneumatically or mechanically
operated have been implemented as electrically powered systems on the
787. Examples include the hydraulic power, equipment cooling, wing
anti-ice, and the auxiliary power unit (APU) and engine start systems.
The criticality of some of these systems is such that their failure
will either reduce the capability of the airplane or the ability of the
crew to cope with adverse operating conditions, or prevent continued
safe flight and landing of the airplane. The airworthiness standards of
part 25 do not contain adequate or appropriate standards for protection
of these systems from the adverse effects of operation without normal
electrical power.
The current rule, 14 CFR 25.1351(d), Amendment 25-72, requires safe
operation under visual flight rules (VFR) conditions for at least five
minutes after loss of all normal electrical power. This rule was
structured around traditional airplane designs that used mechanical
control cables and linkages for flight control. These manual controls
allowed the crew to maintain aerodynamic control of the airplane for an
indefinite period of time after loss of all electrical power. Under
these conditions, the mechanical flight control system provided the
crew with the ability to fly the airplane while attempting to identify
the cause of the electrical failure, start the engine(s) if necessary,
and reestablish some of the electrical power generation capability, if
possible.
To maintain the same level of safety associated with traditional
designs, the 787 must be designed for operation with the normal sources
of engine- and auxiliary-power-unit (APU)-generated electrical power
inoperative. Service experience has shown that loss of all electrical
power from the airplane's engine- and APU-driven generators is not
extremely improbable. Thus, Boeing must demonstrate that the airplane
is capable of recovering adequate primary electrical power generation
for safe flight and landing. This demonstration would provide that the
ability to restore operation of portions of the electrical power
generation capability would be considered if unrecoverable loss of
those portions is shown to be extremely improbable. An alternative
source of electrical power would have to be provided for the time
necessary to restore the minimum power generation capability necessary
for safe flight and landing.
Applicability
As discussed above, these proposed special conditions are
applicable to the 787. Should Boeing 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 proposed special conditions
would apply to that model as well under the provisions of Sec. 21.101.
Conclusion
This action would affect only certain novel or unusual design
features of the 787. It is not a rule of general applicability, and it
would affect only the applicant that applied to the FAA for approval of
these features on the airplane.
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, the Administrator of the Federal Aviation
Administration (FAA) proposes the following special conditions as part
of the type certification basis for the Boeing Model 787-8 airplane.
In lieu of the requirements of 14 CFR 25.1351(d), the following
special conditions apply:
(1) The applicant must show by test or a combination of test and
analysis that the airplane is capable of continued safe flight and
landing with all normal sources of engine- and auxiliary-power-unit
(APU)-generated electrical power inoperative, as prescribed by
paragraphs (1)(a) and (1)(b) below. For purposes of this special
condition, normal sources of electrical power generation do not include
any alternate power sources such as the battery, ram air turbine (RAT),
or independent power systems such as the flight control permanent
magnet generating system. In showing capability for continued safe
flight and landing, consideration must be given to systems capability,
effects on crew workload and operating conditions, and the
physiological needs of the flightcrew and passengers for the longest
diversion time for which approval is sought.
(a) Common cause failures, cascading failures, and zonal physical
threats must be considered in showing compliance with this requirement.
(b) In showing compliance with this requirement, the ability to
restore operation of portions of the electrical power generation and
distribution system may be considered if it can be shown that
unrecoverable loss of those portions of the system is extremely
improbable. An alternative source of electrical power must be provided
for the time required to restore the minimum electrical power
generation capability required for safe flight and landing.
(Unrecoverable loss of all engines may be excluded when showing that
unrecoverable loss of critical portions of the electrical system is
extremely improbable.)
(2) Regardless of any electrical generation and distribution system
recovery capability shown under paragraph 1, sufficient electrical
system capability must be provided--
(a) to allow time to descend, with all engines inoperative, at the
speed that provides the best glide slope, from the maximum operating
altitude to the altitude at which the soonest possible engine restart
could be accomplished, and
(b) to subsequently allow multiple start attempts of the engines
and APU. This capability must be provided in addition to the electrical
capability required by existing part 25 requirements related to
operation with all engines inoperative.
(3) The electrical energy used by the airplane in descending with
engines inoperative from the maximum operating altitude at the best
glide slope, and in making multiple attempts to start the engines and
APU, must be considered when showing compliance with paragraphs (1) and
(2) of these special conditions and with existing 14 CFR part 25
requirements related to continued safe flight and landing.
Issued in Renton, Washington, on October 5, 2007.
Ali Bahrami,
Manager, Transport Airplane Directorate, Aircraft Certification
Service.
[FR Doc. E7-20310 Filed 10-15-07; 8:45 am]
BILLING CODE 4910-13-P