AD 2008-21-04 Airworthiness Directives; Hawker Beechcraft Corporation Model 390 Airplanes

Makes named: hawker beechcraft. Models named: 390. Read the applicability below — it usually turns on serial or part numbers too.

This AD applies to Model 390 airplanes, serial numbers RB-1 and RB-4 through RB-238, that are certificated in any category.

To address this problem, you must do the following, unless already done:   Action Compliance Procedures (1) Modify the cabin barometric pressure switch and cabin altitude high switch installations. Within 25 hours time-in-service (TIS) after October 20, 2008 (the effective date of this AD) or within 30 days after October 20, 2008 (the effective date of this AD), whichever occurs first. Follow Hawker Beechcraft Mandatory Service Bulletin SB 21-3899, original issue, dated May 2008. (2) Perform a functional test of the switches and related systems: (i) If, before the effective date of this AD, you did the flight test method in Part II of the Accomplishment Instructions of the service bulletin referenced in the Procedures column of this paragraph, then the action of paragraph (e)(2) of this AD is not required provided it was done after the modification required in paragraph (e)(1) of this AD. (ii) After the effective date of this AD, the flight test method described in paragraph (e)(2)(i) of this AD is prohibited. Before further flight after the modification of the cabin barometric pressure switch and cabin altitude high switch installations specified in paragraph (e)(1) of this AD. Following Part I—Ground Test Method paragraph 3, Accomplishment Instructions of Hawker Beechcraft Mandatory Service Bulletin SB 21-3899 original issue, dated May 2008. Alternative Methods of Compliance (AMOCs) (f) The Manager, Wichita Aircraft Certification Office (ACO), FAA, has the authority to approve AMOCs for this AD, if requested using the procedures found in 14 CFR 39.19. Send information to ATTN: Erik Brown, Aerospace Engineer, Wichita ACO, 1801 Airport Road, Room 100, Wichita, Kansas 67209; telephone: (316) 946-4132; fax: (316) 946-4107. Before using any approved AMOC on any airplane to which the AMOC applies, notify your appropriate principal inspector (PI) in the FAA Flight Standards District Office (FSDO), or lacking a PI, your local FSDO. Material Incorporated by Reference (g) You must use Hawker Beechcraft Mandatory Service Bulletin SB 21-3899, original issue, dated May 2008, to do the actions required by this AD, unless the AD specifies otherwise. (1) The Director of the Federal Register approved the incorporation by reference of this service information under 5 U.S.C. 552(a) and 1 CFR part 51. (2) For service information identified in this AD, contact Hawker Beechcraft Corporation, P.O. Box 85, Wichita, Kansas 67201-0085; telephone: (800) 429-5372 or (316) 676-3140; http://pubs.hawkerbeechcraft.com . (3) You may review copies at the FAA, Central Region, Office of the Regional Counsel, 901 Locust, Kansas City, Missouri 64106; or at the National Archives and Records Administration (NARA). For information on the availability of this material at NARA, call 202-741-6030, or go to: http://www.archives.gov/federal_register/code_of_federal_regulations/ibr_locations.html . Issued in Kansas City, Missouri, on September 30, 2008. John Colomy, Acting Manager, Small Airplane Directorate, Aircraft Certification Service. [FR Doc. E8-23643 Filed 10-8-08; 8:45 am] BILLING CODE 4910-13-P

This AD is the result of reported occurrences of incorrectly connected barometric switches. Also, the terminal used on the switches may be inadvertently dislodged while performing airplane maintenance in the pedestal area. We are issuing this AD to modify the cabin barometric pressure switch and cabin altitude high switch to prevent them from becoming incorrectly connected or inadvertently disconnected, which may result in no CABIN ALT HI annunciation in the cockpit and no automatic deployment of the cabin oxygen masks. This failure could lead to incapacitation of the crew due to hypoxia with possible inability to control the airplane.