Special Conditions: Boeing Model 787-8 Airplane; Operation Without Normal Electrical Power, 58560-58561 [E7-20310]

Agencies

• Federal Aviation Administration
• DEPARTMENT OF TRANSPORTATION

[Federal Register Volume 72, Number 199 (Tuesday, October 16, 2007)]
[Proposed Rules]
[Pages 58560-58561]
From the Federal Register Online via the Government Printing Office [www.gpo.gov]
[FR Doc No: E7-20310]


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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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Federal Register / Vol. 72, No. 199 / Tuesday, October 16, 2007 / 
Proposed Rules

[[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