[Federal Register Volume 59, Number 220 (Wednesday, November 16, 1994)]
[Unknown Section]
[Page 0]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 94-28285]


[[Page Unknown]]

[Federal Register: November 16, 1994]


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DEPARTMENT OF TRANSPORTATION
14 CFR Part 25

[Docket No. NM-100; Final Special Conditions No. 25-ANM-90]

 

Special Conditions; Dassault Aviation Model Falcon 2000 Airplane, 
High Altitude Operation

AGENCY: Federal Aviation Administration, DOT.

ACTION: Final special conditions; request for comments.

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SUMMARY: These special conditions are issued for the Dassault Aviation 
Model Falcon 2000 airplane. This new airplane will have an unusual 
design feature associated with an unusually high operating altitude 
(47,000 feet), for which the applicable airworthiness regulations do 
not contain adequate or appropriate safety standards. 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.

DATES: The effective date of these special conditions is November 4, 
1994.
    Comments must be received on or before January 2, 1995.

ADDRESSES: Comments on these final special conditions; request for 
comments, may be mailed in duplicate to: Federal Aviation 
Administration, Office of the Assistant Chief Counsel, Attn.: Rules 
Docket (ANM-7), Docket No. NM-100, 1601 Lind Avenue SW., Renton, 
Washington, 98055-4056; or delivered in duplicate to the Office of the 
Assistant Chief Counsel at the above address. Comments must be marked 
``Docket No. NM-100.'' 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, Standardization 
Branch, ANM-113, Transport Airplane Directorate, Aircraft Certification 
Service, 1601 Lind Avenue SW., Renton, Washington, 98055-4056, 
telephone (206) 227-2797.

SUPPLEMENTARY INFORMATION:

Comments Invited

    The FAA has determined that good cause exists for making these 
special conditions effective upon issuance; however, interested persons 
are invited to submit such written data, views, or arguments as they 
may desire. Communications should identify the regulatory docket and 
special conditions number and be submitted in duplicate to the address 
specified above. All communications received on or before the closing 
date for comments will be considered by the Administrator. These 
special conditions may be changed in light of the comments received. 
All comments submitted will be available in the Rules Docket for 
examination by interested persons, both before and after the closing 
date for comments. A report summarizing each substantive public contact 
with FAA personnel concerning this rulemaking will be filed in the 
docket. Persons wishing the FAA to acknowledge receipt of their 
comments submitted in response to this request must submit with those 
comments a self-addressed, stamped postcard on which the following 
statement is made: ``Comments to Docket No. NM-100.'' The postcard will 
be date stamped and returned to the commenter.

Background

    On September 13, 1989, Dassault Aviation, B.P. 24, 33701 Merignac 
Cedex, France, applied for a new type certificate in the transport 
airplane category for the Model Falcon 2000 airplane. The Dassault 
Aviation Model Falcon 2000 is a medium-sized transcontinental business 
jet powered by two General Electric/Garrett CFE 738 turbofan engines 
mounted on pylons extending from the aft fuselage. Each engine will be 
capable of delivering 5,600 lbs. thrust. The airplane will be capable 
of operating with two flight crewmembers and eight passengers.
    The type design of the Model Falcon 2000 contains a number of novel 
and unusual design features for an airplane type certificated under the 
applicable provisions of part 25 of the Federal Aviation Regulations 
(FAR). Those features include the relatively small passenger cabin 
volume and a high maximum operating altitude. The applicable 
airworthiness requirements do not contain adequate or appropriate 
safety standards for the Falcon 2000; therefore, special conditions are 
necessary to establish a level of safety equivalent to that established 
in the regulations.

Type Certification Basis

    Under the provisions of Sec. 21.17 of the FAR, Dassault Aviation 
must show that the Falcon 2000 meets the applicable provisions of part 
25, effective February 1, 1965, as amended by Amendments 25-1 through 
25-69. The certification basis may also include later amendments to 
part 25 that are not relevant to these special conditions. In addition, 
the certification basis for the Falcon 2000 includes part 34, effective 
September 10, 1990, plus any amendments in effect at the time of 
certification; and part 36, effective December 1, 1969, as amended by 
Amendments 36-1 through the amendment in effect at the time of 
certification. These special conditions form an additional part of the 
type certification basis. In addition, the certification basis may 
include other special conditions that are not relevant to these special 
conditions.
    If the Administrator finds that the applicable airworthiness 
regulations (i.e., part 25, as amended) do not contain adequate or 
appropriate safety standards for the Falcon 2000 because of a novel or 
unusual design feature, special conditions are prescribed under the 
provisions of Sec. 21.16 to establish a level of safety equivalent to 
that established in the regulations.
    Special conditions, as appropriate, are issued in accordance with 
Sec. 11.49 of the FAR after public notice, as required by Secs. 11.28 
and 11.29, 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, or should any other model already included on 
the same type certificate be modified to incorporate 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 Feature

    The Dassault Aviation Falcon 2000 will incorporate an unusual 
design feature in that it will be certified to operate up to an 
altitude of 47,000 feet.
    The FAA considers certification of transport category airplanes for 
operation at altitudes greater than 41,000 feet to be a novel or 
unusual feature because current part 25 does not contain standards to 
ensure the same level of safety as that provided during operation at 
lower altitudes. Special conditions have therefore been adopted to 
provide adequate standards for transport category airplanes previously 
approved for operation at these high altitudes, including certain 
Learjet models, the Boeing Model 747, Dassault-Breguet Falcon 900, 
Canadair Model 600, Cessna Model 650, Israel Aircraft Industries Model 
1125, and Cessna Model 560. The special conditions for the Learjet 
Model 45 are considered the most applicable to the Falcon 2000 and its 
proposed operation and are therefore used as the basis for the special 
conditions described below.
    Damage tolerance methods are proposed to be used to ensure pressure 
vessel integrity while operating at the higher altitudes, in lieu of 
the \1/2\-bay crack criterion used in some previous special conditions. 
Crack growth data are used to prescribe an inspection program that 
should detect cracks before an opening in the pressure vessel would 
allow rapid depressurization. Initial crack sizes for detection are 
determined under Sec. 25.571, as amended by Amendment 25-72. The 
maximum extent of failure and pressure vessel opening determined from 
the above analysis must be demonstrated to comply with the 
pressurization section of the proposed special conditions, which state 
that the cabin altitude after failure must not exceed the cabin 
altitude/time curve limits shown in Figures 3 and 4.
    In order to ensure that there is adequate fresh air for crewmembers 
to perform their duties, to provide reasonable passenger comfort, and 
to enable occupants to better withstand the effects of decompression at 
high altitudes, the ventilation system must be designed to provide 10 
cubic feet of fresh air per minute per person during normal operations. 
Therefore, these special conditions require that crewmembers and 
passengers be provided with 10 cubic feet of fresh air per minute per 
person. In addition, during the development of the supersonic transport 
special conditions, it was noted that certain pressurization failures 
resulted in hot ram or bleed air being used to maintain pressurization. 
Such a measure can lead to cabin temperatures that exceed human 
tolerance. Therefore, these special conditions require airplane 
interior temperature limits following probable and improbable failures.
    Continuous flow passenger oxygen equipment is certificated for use 
up to 40,000 feet; however, for rapid decompressions above 34,000 feet, 
reverse diffusion leads to low oxygen partial pressures in the lungs, 
to the extent that a small percentage of passengers may lose useful 
consciousness at 35,000 feet. The percentage increases to an estimated 
60 percent at 40,000 feet, even with the use of the continuous flow 
system. Therefore, to prevent permanent physiological damage, the cabin 
altitude must not exceed 25,000 feet for more than 2 minutes, or 40,000 
feet for any time period. The maximum peak cabin altitude of 40,000 
feet is consistent with the standards established for previous 
certification programs. In addition, at high altitudes the other 
aspects of decompression sickness have a significant, detrimental 
effect on pilot performance (for example, a pilot can be incapacitated 
by internal expanding gases).
    Decompression resulting in cabin altitudes above the 37,000-foot 
limit depicted in Figure 4 approaches the physiological limits of the 
average person; therefore, every effort must be made to provide the 
pilots with adequate oxygen equipment to withstand these severe 
decompressions. Reducing the time interval between pressurization 
failure and the time the pilots receive oxygen will provide a safety 
margin against being incapacitated and can be accomplished by the use 
of mask-mounted regulators. These special conditions therefore require 
pressure demand masks with mask-mounted regulators for the flightcrew. 
This combination of equipment will provide the best practical 
protection for the failures covered by the special conditions and for 
improbable failures not covered by the special conditions, provided the 
cabin altitude is limited.
    As discussed above, these special conditions are applicable to the 
Dassault Aviation Model Falcon 2000. Should Dassault Aviation 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 Sec. 21.101(a)(1).

Conclusion

    This action affects only certain design features on the Dassault 
Aviation Model Falcon 2000 airplane. It is not a rule of general 
applicability and affects only the manufacturer who applied to the FAA 
for approval of these features on the airplane.
    The substance of the special conditions for this airplane has been 
subjected to the notice and comment procedure in several prior 
instances and has been derived without substantive change from those 
previously issued. It is unlikely that prior public comment would 
result in a significant change from the substance contained herein. For 
this reason, and because a delay would significantly affect the 
certification of the airplane, which is imminent, the FAA has 
determined that prior public notice and comment are unnecessary and 
impracticable, and good cause exists for adopting these special 
conditions immediately. Therefore, these special conditions are being 
made effective upon issuance. The FAA is requesting comments to allow 
interested persons to submit views that may not have been submitted in 
response to the prior opportunities for comment described above.

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. app. 1344, 1348(c), 1352, 1354(a), 1355, 
1421 through 1341, 1502, 1651(b)(2), 42 U.S.C. 1857f-10, 4321 et 
seq.; E.O. 11514; and 49 U.S.C. 106(g).

The Special Conditions

    Accordingly, the following special conditions are issued as part of 
the type certification basis for the Dassault Aviation Model Falcon 
2000:

Operation to 47,000 Feet

    1. Pressure Vessel Integrity.
    (a) The maximum extent of failure and pressure vessel opening that 
can be demonstrated to comply with paragraph 4 (Pressurization) of this 
special condition must be determined. It must be demonstrated by crack 
propagation and damage tolerance analysis supported by testing that a 
larger opening or a more severe failure than demonstrated will not 
occur in normal operations.
    (b) Inspection schedules and procedures must be established to 
ensure that cracks and normal fuselage leak rates will not deteriorate 
to the extent that an unsafe condition could exist during normal 
operation.
    (c) With regard to the fuselage structural design for cabin 
pressure capability above 45,000 feet altitude, the pressure vessel 
structure, including doors and windows, must comply with 
Sec. 25.365(d), using a factor of 1.67 instead of the 1.33 factor 
prescribed.
    2. Ventilation. In lieu of the requirements of Sec. 25.831(a), the 
ventilation system must be designed to provide a sufficient amount of 
uncontaminated air to enable the crewmembers to perform their duties 
without undue discomfort or fatigue, and to provide reasonable 
passenger comfort during normal operating conditions and also in the 
event of any probable failure of any system that could adversely affect 
the cabin ventilating air. For normal operations, crewmembers and 
passengers must be provided with at least 10 cubic feet of fresh air 
per minute per person, or the equivalent in filtered, recirculated air 
based on the volume and composition at the corresponding cabin pressure 
altitude of not more than 8,000 feet.
    3. Air Conditioning. In addition to the requirements of 
Sec. 25.831, paragraphs (b) through (e), the cabin cooling system must 
be designed to meet the following conditions during flight above 15,000 
feet mean sea level (MSL):
    (a) After any probable failure, the cabin temperature-time history 
may not exceed the values shown in Figure 1.
    (b) After any improbable failure, the cabin temperature-time 
history may not exceed the values shown in Figure 2.
    4. Pressurization. In addition to the requirements of Sec. 25.841, 
the following apply:
    (a) The pressurization system, which includes for this purpose 
bleed air, air conditioning, and pressure control systems, must prevent 
the cabin altitude from exceeding the cabin altitude-time history shown 
in Figure 3 after each of the following:
    (1) Any probable malfunction or failure of the pressurization 
system. The existence of undetected, latent malfunctions or failures in 
conjunction with probable failures must be considered.
    (2) Any single failure in the pressurization system, combined with 
the occurrence of a leak produced by a complete loss of a door seal 
element, or a fuselage leak through an opening having an effective area 
2.0 times the effective area that produces the maximum permissible 
fuselage leak rate approved for normal operation, whichever produces a 
more severe leak.
    (b) The cabin altitude-time history may not exceed that shown in 
Figure 4 after each of the following:
    (1) The maximum pressure vessel opening resulting from an initially 
detectable crack propagating for a period encompassing four normal 
inspection intervals. Mid-panel cracks and cracks through skin-stringer 
and skin-frame combinations must be considered.
    (2) The pressure vessel opening or duct failure resulting from 
probable damage (failure effect) while under maximum operating cabin 
pressure differential due to a tire burst, engine rotor burst, loss of 
antennas or stall warning vanes, or any probable equipment failure 
(bleed air, pressure control, air conditioning, electrical source(s), 
etc.) that affects pressurization.
    (3) Complete loss of thrust from all engines.
    (c) In showing compliance with paragraphs 4(a) and 4(b) of these 
special conditions (Pressurization), it may be assumed that an 
emergency descent is made by approved emergency procedure. A 17-second 
crew recognition and reaction time must be applied between cabin 
altitude warning and the initiation of an emergency descent.

    Note: For flight evaluation of the rapid descent, the test 
article must have the cabin volume representative of what is 
expected to be normal, such that Dassault Aviation must reduce the 
total cabin volume by that which would be occupied by the 
furnishings and total number of people.

    5. Oxygen Equipment and Supply.
    (a) A continuous flow oxygen system must be provided for the 
passengers.
    (b) A quick-donning pressure demand mask with mask-mounted 
regulator must be provided for each pilot. Quick-donning from the 
stowed position must be demonstrated to show that the mask can be 
withdrawn from stowage and donned with 5 seconds.

BILLING CODE 4910-13-M
  

TR16NO94.000


TR16NO94.001


BILLING CODE 4910-13-C

    Issued in Renton, Washington, on November 4, 1994.
Darrell M. Pederson,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service, ANM-100.
[FR Doc. 94-28285 Filed 11-15-94; 8:45 am]