[Federal Register Volume 67, Number 93 (Tuesday, May 14, 2002)]
[Proposed Rules]
[Pages 34414-34416]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 02-12023]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 25

[Docket No. NM206; Special Conditions No. 25-02-06]


Special Conditions: Fairchild Dornier GmbH, Model 728-100; 
Operation Without Normal Electrical Power

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Notice of proposed special conditions.

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SUMMARY: This action proposes special conditions for the Fairchild 
Dornier GmbH Model 728-100 airplane. This airplane will have a novel or 
unusual design feature when compared to the state of technology 
envisioned in the airworthiness standards for transport category 
airplanes. The airplane design will include an electronic flight 
control system. The applicable airworthiness regulations do not contain 
adequate or appropriate safety standards for this design feature. These 
special conditions, in part, 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 may also be defined.

DATES: Comments must be received on or before June 28, 2002.

ADDRESSES: Comments on this proposal may be mailed in duplicate to: 
Federal Aviation Administration, Transport Airplane Directorate, 
Attention: Rules Docket (ANM-113), Docket No. NM206, 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. NM206. 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: Tom Groves, FAA, International Branch, 
ANM-116, Transport Airplane Directorate, Aircraft Certification 
Service, 1601 Lind Avenue SW., Renton, Washington 98055-4056; telephone 
(425) 227-1503; 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 proposal, 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 action 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

[[Page 34415]]

which the docket number appears. We will stamp the date on the postcard 
and mail it back to you.

Background

    On May 5, 1998, Fairchild Dornier GmbH applied for a type 
certificate for their new Model 728-100 airplane. The Model 728-100 is 
a 70-85 passenger twin-engine regional jet with a maximum takeoff 
weight of 77,600 pounds.

Type Certification Basis

    Under the provisions of 14 CFR 21.17, Fairchild Dornier GmbH must 
show that the Model 728-100 airplane meets the applicable provisions of 
part 25, as amended by Amendments 25-1 through 25-96. Fairchild Dornier 
GmbH has also applied to extend the certification basis to include 
Amendments 25-97, 25-98, and 25-104.
    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 Model 728-100 airplane because of 
a novel or unusual design feature, special conditions are prescribed 
under the provisions of Sec. 21.16.
    In addition to the applicable airworthiness regulations and special 
conditions, the Model 728-100 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, and 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 Sec. 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 novel or 
unusual design feature, the special conditions would also apply to the 
other model under the provisions of Sec. 21.101(a)(1).

Novel or Unusual Design Features

    As noted earlier, the Fairchild Dornier GmbH Model 728-100 airplane 
will include an electronic flight control system. The current 
airworthiness standards of part 25 do not contain adequate or 
appropriate standards for the protection of this equipment from the 
adverse effects of operations without normal electrical power. 
Accordingly, this system is considered to be a novel or unusual design 
feature. Since the loss of all electrical power may be catastrophic to 
the airplane, special conditions are proposed to retain the level of 
safety envisioned by Sec. 25.1351(d).

Discussion

    The Fairchild Dornier GmbH Model 728-100 airplane will require a 
continuous source of electrical power for the electronic flight control 
system. Section 25.1351(d), ``Operation without normal electrical 
power,'' requires safe operation in visual flight rule (VFR) conditions 
for a period of not less than five minutes with inoperative normal 
power. This rule was structured around a traditional design utilizing 
mechanical connections between the flight control surfaces and the 
pilot controls. The Fairchild Dornier GmbH Model 728 will utilize an 
electronic flight control system. With an electronic flight control 
system, there is no mechanical linkage between the pilot controls and 
the flight control surfaces. Pilot control inputs are converted to 
electrical signals which are processed and then transmitted via wires 
to the control surface actuators. At the control surface actuators the 
electrical signals are converted to an actuator command, which moves 
the control surface. Uninterrupted electrical power is necessary to 
ensure the electronic flight control system function.
    Service experience has shown that the loss of all electrical power 
generated by the airplane's engine generators or auxiliary power unit 
(APU) is not extremely improbable. Thus, it must be demonstrated that 
the airplane can continue safe flight and landing after total loss of 
the normal electrical power with only the use of its emergency 
electrical power systems. These emergency electrical power systems must 
be able to power loads that are essential for continued safe flight and 
landing. The emergency electrical power system must be designed to 
supply:
    1. Electrical power required for immediate safety, without the need 
for crew action, following the loss of the normal engine generator 
electrical power system (which includes APU power).
    2. Electrical power required for continued safe flight and landing.
    3. Electrical power required to restart the engines.
    For compliance purposes, a test of the loss of normal engine 
generator power must be conducted to demonstrate that when the failure 
condition occurs during night instrument meteorological conditions 
(IMC), at the most critical phase of the flight relative to the 
electrical power system design and distribution of equipment loads on 
the system, the following conditions are met:
    1 Engine restart capability is provided.
    2. Capability for continued operation in IMC is provided.
    3. The airplane is demonstrated to be capable of continued safe 
flight and landing. The length of time must be computed based on the 
maximum diversion time capability for which the airplane is being 
certified. Consideration for speed reductions resulting from the 
associated failure must be made.
    4. The availability of APU operation should not be considered in 
establishing emergency power system adequacy.

Applicability

    As discussed above, these special conditions are applicable to the 
Fairchild Dornier GmbH Model 728-100. Should Fairchild Dornier GmbH 
apply at a later date for a change to the type certificate to include 
another model incorporating the same novel or unusual design feature, 
these special conditions would apply to that model as well under the 
provisions of section 21.101(a)(1). Fairchild Dornier has submitted 
applications for certification of both increased and reduced passenger 
capacity derivatives of the Model 728-100 airplane. These derivative 
models are designated the Model 928-100 airplane and the Model 528-100 
airplane, respectively. As currently proposed, these derivative models 
share the same design feature of an electronic flight control system as 
the Model 728-100 airplane, and it is anticipated that they will be 
included in the applicability of these proposed special conditions.

Conclusion

    This action affects only certain novel or unusual design features 
on Fairchild Dornier GmbH Model 728-100 airplanes. It is not a rule of 
general applicability, and it affects only the applicant who 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 Federal Aviation Administration (FAA) proposes the

[[Page 34416]]

following special conditions as part of the type certification basis 
for Fairchild Dornier GmbH Model 728-100 airplanes.
    Operation Without Normal Electrical Power. In lieu of compliance 
with Sec. 25.1351(d), it must be demonstrated by test, or combination 
of test and analysis, that the airplane can continue safe flight and 
landing with inoperative normal engine and APU generator electrical 
power (in other words, without electrical power from any source except 
for the battery and any other standby electrical sources). The airplane 
operation should be considered at the critical phase of flight and 
include the ability to restart the engines and maintain flight for the 
maximum diversion time capability being certified.

    Issued in Renton, Washington, on April 23, 2002.
Ali Bahrami,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 02-12023 Filed 5-13-02; 8:45 am]
BILLING CODE 4910-13-P