The following Memorandum was issued by the FAA's Small Airplane Directorate and relates to alternate methods for complying with AD 97-03-02 which requires documenting the mass and residual moments of the control surfaces on the affected sailplanes. Those who wish may use the information in this Memorandum to extend their time of compliance, but care should be taken to heed the warning stated in paragraph 3.
Jim Short, SSA Government Liaison Chairman
[following is the text of an FAA memorandum issued on March 17, 1997)
Subject: INFORMATION: Compliance Time That Provides an Equivalent Level of Safety for Airworthiness Directive (AD) Number 97-03-02
From: Manager, Small Airplane Directorate
Reply to: Kiesov Aircraft Certification Service, ACE-100
Telephone (816) 426-6934
To: File for Docket Number 96-CE-38-AD
1. The primary purpose of AD 997-03-02 is to document the mass and residual moment of the control surfaces for a reference point for each sailplane. The manufacturer's type design did not include weight and mass balancing data for the control surfaces. Therefore, if there are any modifications or repairs to the control surfaces, there are no tolerances for the mechanic to ensure that the control surfaces are within acceptable limits. this AD requres that each sailplane owner/operatoir determine control surface weights and associated mass balancing as a baseline.
2. As an alternative compliance time that provides an equivalent level of safety to the intent of AD 97-03-02, the owner/operator does not have to remove and record the control surface weights and mass balance moments until the sailplane is scheduled to be repaired or repainted. (Note: The AD currently requires compliance within 3 months). The amendments to the maintenance manuals, as specified in paragraph (b) of the AD must be inserted within the compliance time stated (3 months from the effective date of the AD).
3. It is specifically noted that if the control surfaces are damaged to the point that an accurate mass balancing cannot be determined, the method described in AD 97-03-02 will not be appropriate and may not be used. If the sailplane control surfaces are damaged to the degree that an accurate weight and mass balancing moment cannot be determined, the owner/operator must contact the manufacturer for an approved method of repair, to include limits for weight and mass balancing.
4. This alternative method of change in compliance time has been reviewed and accepted by the Aircraft Evaluation Group, MKC-AEG.
For additional information, please contact Mr. Mike Kiesov.
Michael Gallagher (s)
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