
[Federal Register Volume 78, Number 211 (Thursday, October 31, 2013)]
[Proposed Rules]
[Pages 65233-65234]
From the Federal Register Online via the Government Printing Office [www.gpo.gov]
[FR Doc No: 2013-25843]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 25

[Docket No. FAA-2013-0858; Notice No. 25-13-09-SC]


Special Conditions: Bombardier Inc., Models BD-500-1A10 and BD-
500-1A11 Series Airplanes; Fuselage Post-Crash Fire Survivability

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Notice of proposed special conditions.

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SUMMARY: This action proposes special conditions for the Bombardier 
Inc. Models BD-500-1A10 and BD-500-1A11 series airplanes. These 
airplanes will have a novel or unusual design feature associated with 
aluminum-lithium fuselage construction that may provide different 
levels of protection from post-crash fire threats than similar aircraft 
constructed from traditional aluminum structure. The applicable 
airworthiness regulations do not contain adequate or appropriate safety 
standards for this design feature. 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.

DATES: Send your comments on or before December 16, 2013.

ADDRESSES: Send comments identified by docket number FAA-2013-0858 
using any of the following methods:
     Federal eRegulations Portal: Go to http://www.regulations.gov/ and follow the online instructions for sending 
your comments electronically.
     Mail: Send comments to Docket Operations, M-30, U.S. 
Department of Transportation (DOT), 1200 New Jersey Avenue SE., Room 
W12-140, West Building Ground Floor, Washington, DC 20590-0001.
     Hand Delivery or Courier: Take comments to Docket 
Operations in Room W12-140 of the West Building Ground Floor at 1200 
New Jersey Avenue SE., Washington, DC, between 9 a.m. and 5 p.m., 
Monday through Friday, except federal holidays.
     Fax: Fax comments to Docket Operations at 202-493-2251.
    Privacy: The FAA will post all comments it receives, without 
change, to http://www.regulations.gov/, including any personal 
information the commenter provides. Using the search function of the 
docket Web site, anyone can find and read the electronic form of all 
comments received into any FAA docket, including the name of the 
individual sending the comment (or signing the comment for an 
association, business, labor union, etc.). DOT's complete Privacy Act 
Statement can be found in the Federal Register published on April 11, 
2000 (65 FR 19477-19478), as well as at http://DocketsInfo.dot.gov/.
    Docket: Background documents or comments received may be read at 
http://www.regulations.gov/ at any time. Follow the online instructions 
for accessing the docket or go to the Docket Operations in Room W12-140 
of the West Building Ground Floor at 1200 New Jersey Avenue SE., 
Washington, DC, between 9 a.m. and 5 p.m., Monday through Friday, 
except federal holidays.

FOR FURTHER INFORMATION CONTACT: Alan Sinclair, FAA, Airframe and Cabin 
Safety Branch, ANM-115 Transport Airplane Directorate, Aircraft 
Certification Service, 1601 Lind Avenue SW., Renton, Washington 98057-
3356; telephone 425-227-2195; facsimile 425-227-1232.

SUPPLEMENTARY INFORMATION:

Comments Invited

    We invite interested people to take part in this rulemaking by 
sending 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 will consider all comments we receive on or before the closing 
date for comments. We may change these special conditions based on the 
comments we receive.

Background

    On December 10, 2009, Bombardier Inc. applied for a type 
certificate for their new Models BD-500-1A10 and BD-500-1A11 series 
airplanes (hereafter collectively referred to as ``C-series''). The C-
series airplanes are swept-wing monoplanes with a pressurized cabin. 
They share an identical supplier base and significant common design 
elements. The fuselage is an aluminum alloy material, blended double-
bubble design, sized for nominal 5-abreast seating. Each airplane's 
powerplant

[[Page 65234]]

consists of two under wing Pratt and Whitney PW1524G ultra-high bypass, 
geared turbofan engines. Flight controls are fly-by-wire systems with 
two passive/uncoupled side sticks. Avionics include five landscape 
primary cockpit displays. The dimensions of the airplanes encompass a 
wingspan of 115 feet; a height of 37.75 feet; and a length of 114.75 
feet for the Model BD-500-1A10 and 127 feet for the Model BD-500-1A11. 
Passenger capacity is designated as 110 for the Model BD-500-1A10 and 
125 for the Model BD-500-1A11. Maximum takeoff weight is 131,000 pounds 
for the Model BD-500-1A10 and 144,000 pounds for the Model BD-500-1A11. 
Maximum takeoff thrust is 21,000 pounds for the Model BD-500-1A10 and 
23,300 pounds for the Model BD-500-1A11. Range is 3,394 miles (5,463 
kilometers) for both models of airplanes. Maximum operating altitude is 
41,000 feet for both models of airplanes.
    The fuselage of the Bombardier C-series airplanes will be 
fabricated using aluminum-lithium construction. Structure fabricated 
from aluminum-lithium may provide different levels of protection from 
post-crash fuel-fed fire threats than similar aircraft constructed from 
traditional aluminum structure.
    There are no existing regulations that adequately ensure that 
aluminum-lithium structure offers passengers the same protection from a 
post-crash fire condition as would a conventional aluminum structure. 
These proposed special conditions are necessary to ensure that the 
Bombardier C-series airplanes provide a level of safety equivalent to 
that provided by Title 14, Code of Federal Regulations (14 CFR) part 
25.

Type Certification Basis

    Under the provisions of 14 CFR 21.17, Bombardier Inc. must show 
that the C-series airplanes meet the applicable provisions of part 25 
as amended by Amendments 25-1 through 25-129 thereto.
    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 C-series airplanes because of a 
novel or unusual design feature, special conditions are prescribed 
under the provisions of Sec.  21.16.
    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 Sec.  21.101.
    In addition to the applicable airworthiness regulations and special 
conditions, the C-series airplanes 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 under Sec.  611 of Public Law 92-574, 
the ``Noise Control Act of 1972.''
    The FAA issues special conditions, as defined in 14 CFR 11.19, in 
accordance with Sec.  11.38, and they become part of the type-
certification basis under Sec.  21.17(a)(2).

Novel or Unusual Design Features

    The Bombardier C-series airplanes will incorporate the following 
novel or unusual design features: The fuselage will be fabricated using 
aluminum-lithium materials instead of conventional aluminum.
    The performance of airplanes consisting of a conventional aluminum 
fuselage is understood based on service history and extensive 
intermediate and large-scale fire testing. The new aluminum-lithium 
materials must provide the same levels of protection against post-crash 
fuel-fed fire threats.

Discussion

    The certification basis for the Bombardier C-series airplanes 
includes meeting the burn-through requirements defined in Sec.  
25.856(b). The Bombardier C-series airplanes are introducing a new 
material from what has traditionally been shown to be survivable from a 
toxic standpoint. Toxicity levels from post-crash fire threats are 
typically more severe than threats generated from an in-flight fire 
with regards to the quantity level of toxins produced by off-gases from 
burning materials. Therefore, it is necessary to ensure that the 
material being used does not introduce a new hazard that would reduce 
the survivability of the passengers during a post-crash situation, or 
provide levels of toxic fumes that would be lethal or incapacitating, 
thus preventing evacuation of the aircraft in a crash scenario.
    Bombardier Inc. will have to demonstrate that aluminum-lithium 
material does not produce levels of toxic fumes that will reduce the 
survivability of the passengers or their ability to evacuate when 
compared to typically constructed aluminum airplanes.
    A way of showing acceptable capability is to conduct a laboratory-
scale test to assess the survivability characteristics of this non-
traditional fuselage material. If negligible amounts of combustion 
products are produced in this test, the material can be considered 
acceptable with respect to post crash survivability. A test method 
developed by the FAA's William J. Hughes Technical Center should be 
utilized (Ref. DOT/FAA/AR-TN07/15 dated August 2008).
    Related regulations, including Sec. Sec.  25.853 and 25.856(a), 
remain valid for this airplane, but they do not reflect the potential 
threat generated from toxic levels of gases produced from aluminum-
lithium materials.

Applicability

    As discussed above, these special conditions are applicable to the 
Model BD-500-1A10 and BD-500-1A11 series airplanes. Should Bombardier 
Inc. apply at a later date for a change to the type certificate to 
include another model incorporating the same novel or unusual design 
feature, the special conditions would apply to that model as well.

Conclusion

    This action affects only certain novel or unusual design features 
on two model series of airplanes. 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, the Federal Aviation Administration (FAA) proposes the 
following special conditions as part of the type certification basis 
for Bombardier Inc. Model BD-500-1A10 and BD-500-1A11 (C-series) 
airplanes.
    The Bombardier C-series airplanes must show that any toxic levels 
of gases produced from the aluminum-lithium material are in no way an 
additional threat to the passengers and their ability to evacuate when 
compared to a typically constructed aluminum airplane exposed to a 
post-crash fuel-fed fire.

    Issued in Renton, Washington, on September 19, 2013.
Ross Landes,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 2013-25843 Filed 10-30-13; 8:45 am]
BILLING CODE 4910-13-P


