81-06-02 FROST ENGINEERING DEVELOPMENT CORPORATION: Amendment 39-4059. Applies to emergency descent devices installed on Boeing 747, Lockheed L-1011, and Airbus Industrie A-300 airplanes. \n\n\tCompliance required as indicated. To prevent failure of emergency descent devices accomplish the following: \n\n\tA.\tWithin 30 days from the effective date of this AD, unless already accomplished, inspect Frost Engineering descent devices for broken handle straps in accordance with paragraph 2, steps (1), (2), and (4) of Frost Engineering Development Corporation Service Bulletin 379103-25-002 dated September 29, 1980, or in a manner approved by the Chief, Seattle Area Aircraft Certification Office, FAA Northwest Region. \n\n\tB.\tDescent devices found to have a broken handle strap must be modified in accordance with paragraph 2, steps (6) through (9) of Frost Engineering Development Corporation Service Bulletin 379103-25-002 dated September 29, 1980, or in a manner approved by the Chief, Seattle Area Aircraft Certification Office, FAA Northwest Region. \n\n\tC.\tWithin 120 days from the effective date of this AD, unless already accomplished, modify the descent devices found to have a magnetic handle strap in accordance with paragraph 2, steps (5) through (9) of Frost Engineering Development Corporation Service Bulletin 379103-25-002 dated September 29, 1980, or in a manner approved by the Chief, Seattle Area Aircraft Certification Office, FAA Northwest Region. \n\n\tD.\tWithin 120 days from the effective date of this AD, replace descent devices P/N 379103-1, serial numbers 1 through 0134, with other FAA approved descent devices. \n\n\tE.\tUpon the request of the operator, and subject to prior approval by the Chief, Seattle Area Aircraft Certification Office, FAA Northwest Region, an FAA Aviation Safety Inspector may adjust the compliance times if the request contains substantiating data to justify the change. \n\n\tThe manufacturer's specification and procedures identified and described in this directive are incorporated herein and made a part hereof pursuant to 5 U.S.C. 552(a)(1). \n\n\tAll persons affected by this directive who have not already received these documents from the manufacturer, may obtain copies upon request to Frost Engineering Development Corporation, P.O. Box 1294, Englewood, Colorado 80150. These documents may also be examined at FAA Northwest Region, 9010 East Marginal Way South, Seattle, Washington 98108. \n\n\tThis amendment becomes effective March 19, 1981.