Source: https://www.federalregister.gov/documents/2008/09/23/E8-22154/special-conditions-honda-aircraft-company-model-ha-420-hondajet-airplane-fire-extinguishing
Timestamp: 2018-07-21 18:31:14
Document Index: 60688747

Matched Legal Cases: ['art 23', 'art 23', 'art 23', 'art 21', '§\u200921', 'art 23', 'art 36', 'art 34', 'art 23', '§\u200921', '§\u200923', '§\u200923', '§\u200923', '§\u200923']

Federal Register :: Special Conditions; Honda Aircraft Company, Model HA-420 HondaJet Airplane; Fire Extinguishing
Special Conditions; Honda Aircraft Company, Model HA-420 HondaJet Airplane; Fire Extinguishing
54675-54677 (3 pages)
Docket No. CE287, Special Conditions No. 23-227-SC
The Final Special Conditions
https://www.federalregister.gov/d/E8-22154 https://www.federalregister.gov/d/E8-22154
This notice issues special conditions for the Honda Aircraft Start Printed Page 54676Company, Model HA-420 HondaJet Airplane. This new airplane will have novel and unusual design features not typically associated with normal, utility, acrobatic, and commuter category airplanes. These design features include turbofan engines and engine location, for which the applicable regulations do not contain adequate or appropriate airworthiness standards. These special conditions contain the additional airworthiness standards that the Administrator considers necessary to establish a level of safety equivalent to that established by the existing airworthiness standards.
Leslie B. Taylor, Aerospace Engineer, Standards Office (ACE-110), Small Airplane Directorate, Aircraft Certification Service, Federal Aviation Administration, Room 301, 901 Locust Street, Kansas City, Missouri 64106; telephone (816) 329-4134, e-mail: leslie.b.taylor@faa.gov.
On October 11, 2006, Honda Aircraft Company, Greensboro, North Carolina, made an application to the FAA for a new Type Certificate for the Honda Model HA-420 HondaJet. The Honda Model HA-420 HondaJet is an all new very light jet, twin engine, high performance, low wing, aft overwing mounted turbofan engine powered aircraft in the normal category including flight into known icing conditions, Reduced Vertical Separation Minima (RVSM) and single pilot operations. The Model HA-420 HondaJet design criteria includes: 9963 pounds maximum gross weight, estimated maximum speed of 258 KIAS/0.72 Mach, cruise speed of 420 KTAS at 30,000 feet, and a 43,000 foot maximum altitude.
Part 23 has historically addressed fire protection through prevention, identification, and containment. Prevention has been provided through minimizing the potential for ignition of flammable fluids and vapors. Identification has traditionally been provided by the location of the engines within the pilot's primary field of view and/or with the incorporation of fire detection systems. This philosophy has provided for both the rapid detection of a fire and confirmation when it has been extinguished. Containment has been provided through the isolation of designated fire zones through flammable fluid shutoff valves and firewalls. The containment philosophy also ensures that components of the engine control system will function effectively to permit a safe shutdown of the engine. However, containment has only been required to be demonstrated for 15 minutes. In event of a fire in a traditional part 23 airplane, the corrective action is to land as soon as possible. For a small, simple aircraft originally envisioned by part 23, it is possible to descend the aircraft to a suitable landing site within 15 minutes. Thus, if the fire is not extinguished, the occupants can safely exit the aircraft before the firewall is breached. These simple and traditional aircraft normally have the engine located away from critical flight control systems and primary structure. This has ensured that, throughout the fire event, the pilot can continue safe flight and control. It has also made predicting the effects of a fire relatively easy. Other design features of these simple and traditional aircraft, such as low stall speeds and short landing distances, ensure that, even in the event of an off-field landing, the potential for a catastrophic outcome has been minimized.
The certification basis for the Model HA-420 HondaJet does require that a fire detection system be installed. However, due to the engine location, fire extinguishing is also considered a requirement. A sustained fire could result in loss of control of the airplane and damage to the primary structure before an emergency landing could be made.
Under the provisions of 14 CFR, part 21, § 21.17, Honda Aircraft Company must show that the Model HA-420 HondaJet meets the applicable provisions of 14 CFR, part 23, effective February 1, 1965, as amended by Amendments 23-1 through Amendment 23-55, effective March 1, 2002; 14 CFR, part 36, effective December 1, 1969, through the amendment effective on the date of type certification; 14 CFR, part 34; exemptions, if any; and the special conditions adopted by this rulemaking action.
The Honda Aircraft Company, Model HA-420 HondaJet will incorporate the following novel or unusual design features:
The Model HA-420 HondaJet design includes engines mounted aft on the top of the wings; therefore, early visual detection of engine fires is precluded. The applicable existing regulations do not require fire extinguishing systems for engines. Aft mounted engine installations were not envisaged in the development of part 23; therefore, special conditions for a fire extinguishing system with the applicable agents, containers, and materials for the engines of the Model HA-420 HondaJet are appropriate.
A notice of proposed special conditions, Notice No. 23-08-04-SC, for the Model HA-420 HondaJet was published on June 25, 2008 (73 FR 35979). No comments were received, and the special conditions are adopted as proposed.
As discussed above, these special conditions are applicable to the Model HA-420 HondaJet. Should Honda Aircraft Company 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 airplane. 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 identified.
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.
Accordingly, the Federal Aviation Administration (FAA) issues the following special conditions as part of the type certification basis for the Honda Aircraft Company, Model HA-420 HondaJet airplane:
SC 23.1195, Fire extinguishing systems—Add the requirements of 14 CFR § 23.1195 as modified below while deleting, “For commuter category airplanes.” Start Printed Page 54677
(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 except for embedded engines where a “two-shot” system is required.
SC 23.1197, Fire extinguishing agents—Add the requirement of 14 CFR § 23.1197 while deleting, “For commuter category airplanes.”
(b) If any toxic extinguishing agent is used, provisions must be made to prevent harmful concentrations of fluid or fluid vapors (from leakage during normal operation of the airplane or as a result of discharging the fire extinguisher on the ground or in flight) from entering any personnel compartment, even though a defect may exist in the extinguishing system. This must be shown by test except for built-in carbon dioxide fuselage compartment fire extinguishing systems for which:
SC 23.1199, Extinguishing agent containers—Add the requirements of 14 CFR § 23.1199 while deleting, “For commuter category airplanes.”
(1) Falling below that necessary to provide an adequate rate of discharge, or
SC 23.1201, Fire extinguishing systems materials—Add the requirements of § 23.1201 while deleting, “For commuter category airplanes.”
Fire extinguisher system materials must meet the following requirements:
Issued in Kansas City, Missouri on September 15, 2008.
[FR Doc. E8-22154 Filed 9-22-08; 8:45 am]