Airworthiness standards: Special conditions Raytheon Aircraft Co. model 3000 airplane,
[Federal Register: August 27, 1998 (Volume 63, Number 166)]
[Proposed Rules]
[Page 45772-45773]
From the Federal Register Online via GPO Access [wais.access.gpo.gov]
[DOCID:fr27au98-40]
DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 23
[Docket No. CE147, Notice No. 23-98-03-SC]
Special Conditions: Raytheon Aircraft Company, Model 3000, Airplane Design
AGENCY: Federal Aviation Administration (FAA), DOT.
ACTION: Notice of proposed special conditions.
SUMMARY: This notice proposes special conditions for the Raytheon Model 3000 airplane. This airplane will have novel or unusual design features associated with the digital electronic engine/propeller controls and the suction defueling system. The applicable airworthiness regulations do not contain adequate or appropriate safety standards for these design features. 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.
DATE: Comments must be received on or before September 28, 1998.
ADDRESS: Comments on this proposal may be mailed in duplicate to: Federal Aviation Administration, Regional Counsel, ACE-7, Attention: Rules Docket, Docket No. CE147, 601 East 12th Street, Kansas City, Missouri 64106, or delivered in duplicate to the Regional Counsel at the above address. Comments must be marked: CE147. Comments may be inspected in the Rules Docket weekdays, except Federal holidays, between 7:30 a.m. and 4:00 p.m.
FOR FURTHER INFORMATION CONTACT: Dave Keenan, Federal Aviation Administration, Aircraft Certification Service, Small Airplane Directorate, ACE-111, 601 East 12th Street, Kansas City, Missouri, 816- 426-6934, fax 816-426-2169.
SUPPLEMENTARY 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 in this notice 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 filedin the docket. Persons wishing the FAA to acknowledge receipt of their comments submitted in response to this notice must include with those comments a self-addressed, stamped postcard on which the following statement is made: ``Comments to CE147.'' The postcard will be date stamped and returned to the commenter.
Background
On January 15, 1996, Raytheon Aircraft Company (formerly Beech Aircraft Corporation) applied for a Type Certificate (TC) for their new Model 3000. The Model 3000 is an all-metal, low-wing monoplane of conventional construction, powered by a single Pratt & Whitney (P&W) PT6A-68 engine flat rated at 1100 SHP. The airframe will be stressed for 7g positive and 3.5g negative loading. Maximum takeoff weight will be 6,300 pounds. The crew compartment will be pressurized to a maximum differential of 3.6 psig and accommodate two pilots equipped with zero- zero ejection seats in a stepped tandem seating arrangement. The airplane will feature a 3,000 psi hydraulic system, powered by a single engine driven pump, to operate the landing gear, flaps, and speed brakes. The V/‹INF›mo‹/INF›/ for the Model 3000 will be 320 KCAS, and the maximum altitude will be 31,000 feet MSL. Each cockpit will be equipped with electronic flight instruments for primary attitude, heading, and navigation information display.
Type Certification Basis
Under the provisions of 14 CFR part 21 Sec. 21.17, Raytheon Aircraft Company must show that the Model 3000 meets the applicable provisions of part 23, effective February 1, 1965, as amended by Amendments 23-1 through 23-47; 14 CFR part 23, Secs. 23.201, 23.203, and 23.207, as amended by Amendment 23-50; 14 CFR part 34, effective September 10, 1990, as amended by the amendment in effect on the date of
[[Page 45773]]
certification; 14 CFR part 36, effective December 1, 1969, as amended by Amendment 36-1 through the amendment in effect on the day of certification; The Noise Control Act of 1972; and special conditions for Protection from High Intensity Radiated Fields (HIRF); exemptions, if any; equivalent level of safety findings, if any; and the special conditions adopted by this rulemaking action.
If the Administrator finds that the applicable airworthiness regulations (part 23) do not contain adequate or appropriate safety standards for the Model 3000 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 3000 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 Sec. 611 of Public Law 92-574, the ``Noise Control Act of 1972.''
Special conditions, as appropriate, are issued in accordance with Sec. 11.49 after public notice, as required by Secs. 11.28 and 11.29(b), 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
The Model 3000 will incorporate the following novel or unusual design features:
Digital Electronic Engine Controls
The Model 3000 design includes a digital electronic engine/ propeller control, known as a Power Management Unit (PMU). Although the precedent for electronic engine controls has been previously established, the PMU utilized on the Model 3000 performs functions not envisaged when part 23 was developed. With the Model 3000, the (Power Control Lever) PCL is a single lever, which has a mechanical and electrical interface to the PMU in order to produce ``jet-like'' thrust characteristics during rapid power changes and at low power conditions. PCL movement is transmitted to the PMU, which, in turn, controls fuel flow, gas generator speed, and propeller speed. Propeller pitch is not pilot controllable; therefore, a separate propeller control lever is not supplied. During normal operation, propeller pitch is governed at 100 percent Np. Low airspeed and power combinations result in propeller pitch going to the mechanical low pitch stop (similar to a fixed-pitch propeller). During large power transitions below 100 percent Np (idle to takeoff power), the PMU will control propeller pitch. The PMU is utilized to control the thrust response of the engine-propeller combination and it prohibits operation of the engine-propeller combination in propeller RPM ranges with adverse vibration characteristics. There is no guidance in part 23 concerning the protection of the PMU from the indirect effects of lightning.
Suction Defuel Capability
The Model 3000 design includes a suction defuel capability not envisaged when part 23 was developed. It is understood that suction defuel is a common feature in part 25 airplanes. The Model 3000 airplane will have pressure fuel and defuel as well as gravity fuel and defuel capability. Pressure defueling essentially entails reversing the pumps on the fueling vehicle and ``sucking'' fuel from the airplane though the servicing port. Section 23.979 addresses pressure fueling but not suction defueling. Any suction defuel system components, in addition to meeting the general requirements for part 23 fuel systems, must also function as intended.
Applicability
As discussed above, these special conditions are applicable to the Model 3000. Should Raytheon 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 Sec. 21.101(a)(1).
Conclusion
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 for the FAA for approval of these features on the airplane.
List of Subjects in 14 CFR Part 23
Aircraft, Aviation safety, Signs and symbols.
Citation
The authority citation for these special conditions is as follows:
Authority: 49 U.S.C. (106(g), 40113 and 44701; 14 CFR part 21, Secs. 21.16 and 21.17; and 14 CFR part 11, Secs. 11.28 and 11.29(b).
The Proposed Special Conditions
Accordingly, the Federal Aviation Administration (FAA) proposes the following special conditions as part of the type certification basis for Raytheon Aircraft Company Model 3000 airplanes.
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Digital Electronic Engine/Propeller Control (PMU)
(a) Any failure of the Power Management Unit must be annunciated to the crew.
(b) Failures of the Power Management Unit that affect flight characteristics must be identified and evaluated, and appropriate flight manual procedures developed, including possible prohibitions on continued flight or dispatch.
(c) The functioning of the Power Management Unit must be protected to ensure that the control will continue to perform critical functions (functions whose failure condition would prevent continued safe flight and landing) after the aircraft is exposed to lightning.
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Suction Defuel
(a) The airplane defueling system (not including fuel tanks and fuel tank vents) must withstand an ultimate load that is 2.0 times the load arising from the maximum permissible defueling pressure (positive or negative) at the airplane fueling connection.
Issued in Kansas City, Missouri on August 14, 1998. Michael Gallagher, Manager, Small Airplane Directorate, Aircraft Certification Service.
[FR Doc. 98-23006Filed8-26-98; 8:45 am]
BILLING CODE 4910-13-M
