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Proposed Rule

Special Conditions: Eclipse Aviation Corporation, Model 500; Fire Extinguishing System for Aft Mounted Engine Installations

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Start Preamble


Federal Aviation Administration (FAA), DOT.


Notice of proposed special conditions.


This action proposes special conditions for the Eclipse Aviation Corporation Model 500 airplane. This airplane design includes aft mounted turbine engines. 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.


Comments must be received on or before February 28, 2002.


Comments on this proposal may be mailed in duplicate to: Federal Aviation Administration, Regional Counsel, Attention: Rules Docket No. CE171, 901 Locust, Room 506, Kansas City, Missouri 64106; or delivered in duplicate to the Regional Counsel at the above address. Comments must be marked: Docket No. CE171. Comments may be inspected in the Rules Docket weekdays, except Federal holidays, between 7:30 a.m. and 4 p.m.

Start Further Info


Mr. Lowell Foster, Federal Aviation Administration, Aircraft Certification Service, Small Airplane Directorate, ACE-111, 901 Locust Street, Kansas City, Missouri, 816-329-4111, fax 816-329-4090.

End Further Info End Preamble Start Supplemental Information


Comments Invited

Interested persons are invited to participate in the making of these proposed special conditions by submitting such written data, views, or arguments as they may desire. Communications should identify the regulatory docket or notice 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. The proposals described Start Printed Page 4216in this action may be changed in light of the comments received. All comments received 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 action must include with those comments a self-addressed, stamped postcard on which the following statement is made: “Comments to Docket No. CE171.” The postcard will be date stamped and returned to the commenter.


On November 9, 2000, Eclipse Aviation Corporation applied for a type certificate for their new Model 500.

The Model 500 design includes turbine engines mounted aft on the fuselage, which means early visual detection of engine fire is precluded. The applicable existing regulations do not require fire extinguishing systems for engines. Aft mounted turbine engine installations, along with the need to protect such installed engines from fires, were not envisioned in the development of part 23; therefore, a special condition for a fire extinguishing system for the engines of the Model 500 is required.

Type Certification Basis

Under the provisions of 14 CFR 21.17, Eclipse Aviation Corporation must show that the Model 500 meets the following:

(1) Applicable provisions of 14 CFR part 23, effective December 18, 1964, as amended by Amendments 23-1 through 23-54 (September 14, 2000).

(2) Part 34 of the Federal Aviation Regulations effective September 10, 1990, plus any amendments in effect on the date of type certification.

(3) Part 36 of the Federal Aviation Regulations effective December 1, 1969, as amended by Amendment 36-1 through the amendment in effect on the date of type certification.

(4) Noise Control Act of 1972.

(5) Special Conditions:

a. Special Conditions for Protection from High Intensity Radiated Fields (HIRF) will be required.

b. Special Conditions for aft mounted engines to include Engine Fire Extinguishing System or Fire Detection and Control will be required. A fire extinguishing system is not required if Eclipse Aviation Corporation can show that a fire that starts in any engine compartment is detectable and controllable.

c. Special Conditions for an Electronic Engine Control System will be required.

(6) Exemptions approved by the FAA (14 CFR 11.27).

(7) Equivalent Level of Safety Findings, as necessary.

If the Administrator finds that the applicable airworthiness regulations (i.e., part 23) do not contain adequate or appropriate safety standards for the Model 500 because of a novel or unusual design feature, special conditions are prescribed under the provisions of § 21.16.

In addition to the applicable airworthiness regulations and special conditions, the Model 500 must comply with the part 23 fuel vent and exhaust emission requirements of 14 CFR part 34 and the part 23 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 appropriate, as defined in § 11.19, are issued in accordance with § 11.38 after public notice and become part of the type certification basis in accordance with § 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 same novel or unusual design feature, the special conditions would also apply to the other model under the provisions of § 21.101.

Novel or Unusual Design Features

The Eclipse Model 500 will incorporate the following novel or unusual design features: Turbine engines mounted on the aft of the fuselage. Aft mounted turbine engine installations need to be protected from fire since early visual detection of engine fires is not possible. This notice proposes a special condition for a fire extinguishing system for the engines of the Model 500.


As discussed above, these special conditions are applicable to the Eclipse Model 500. Should Eclipse Aviation Corporation 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 under the provisions of § 21.101.


This action affects only certain novel or unusual design features on one model of 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.

Start List of Subjects

List of Subjects in 14 CFR Part 23

  • Aircraft
  • Aviation safety
  • Signs and symbols
End List of Subjects


The authority citation for these special conditions is as follows:

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Authority: 49 U.S.C. 106(g), 40113 and 44701; 14 CFR 21.16 and 21.17; and 14 CFR 11.38 and 11.19.

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The Proposed Special Conditions

Accordingly, the Federal Aviation Administration (FAA) proposes the following special conditions as part of the type certification basis for the Eclipse Aviation Corporation Model 500.

Engine Fire Extinguishing System

(a) Fire extinguishing systems must be installed and compliance must be shown with the following:

(1) Except for combustor, turbine, and tailpipe sections of turbine-engine installations that contain lines or components carrying flammable fluids for which a fire originating in these sections can be controllable, a fire extinguisher system must serve each engine compartment.

(2) The fire extinguishing system, the quantity of the extinguishing agent, the rate of discharge, and the discharge distribution must be adequate to extinguish fires. An individual “one shot” system may be used.

(3) The fire extinguishing system for a nacelle must be able to simultaneously protect each compartment of the nacelle for which protection is provided.

(b) Fire extinguishing agents must meet the following requirements:

(1) Be capable of extinguishing flames emanating from any burning of fluids or other combustible materials in the area protected by the fire extinguishing system.

(2) Have thermal stability over the temperature range likely to be experienced in the compartment in which they are stored; and

(3) If any toxic extinguishing agent is used, provisions must be made to prevent harmful concentrations of fluid or vapors from entering any personnel compartment even though a defect may exist in the extinguishing system.

(c) Fire extinguishing agent containers must meet the following requirements: Start Printed Page 4217

(1) Have a pressure relief to prevent bursting of the container by excessive internal pressures.

(2) The discharge end of each discharge line from a pressure relief connection must be located so the discharge of the fire extinguishing agent would not damage the airplane. The line must also be located or protected to prevent clogging caused by ice or other foreign matter.

(3) A means must be provided for each fire extinguishing agent container to indicate that the container has discharged or that the charging pressure is below the established minimum necessary for proper functioning.

(4) The temperature of each container must be maintained, under intended operating conditions, to prevent the pressure in the container from falling below that necessary to provide an adequate rate of discharge, or rising high enough to cause premature discharge; and

(5) If a pyrotechnic capsule is used to discharge the fire extinguishing agent each container must be installed so that temperature conditions will not cause hazardous deterioration of the pyrotechnic capsule.

(d) Fire extinguisher system materials must meet the following requirements:

(1) No material in any fire extinguishing system may react chemically with any extinguishing agent so as to create a hazard, and

(2) Each system component in an engine compartment must be fireproof.

Start Signature

Issued in Kansas City, Missouri on January 14, 2002.

James E. Jackson,

Acting Manager, Small Airplane Directorate, Aircraft Certification Service.

End Signature End Supplemental Information

[FR Doc. 02-2143 Filed 1-28-02; 8:45 am]