# AD 88-12-08: Tow-Hook Knob - Type: Airworthiness directive - Status: Current - Products: Burkhart Grob Luft-Und G103 Twin Astir, G103 Twin II and G103A Twin II Acro - Effective: June 9, 1988 - Superseded by: Nothing supersedes this AD - Product type: Aircraft, Glider - Amendment: 39-5915 - Registered aircraft: 95 may be affected, by airframe or engine model (OpenAirDocs) - FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/261B8456684C97CD86256A4E004CC258.0001 - DRS record last changed: May 30, 2024 - Page: https://openairdocs.org/ad/88-12-08 ## The airworthiness directive 88-12-08 GROB WERKE GMBH AND CO. KG (BURKHART GROB): Amendment 39-5915. Applies to the following models certificated in any category: G103 TWIN ASTIR, Serial Numbers 3000 through 3291. G103 TWIN II, Serial Numbers 3501 through 3878. G103A TWIN II ACRO, Serial Numbers 3501 through 3878 with supplement "K" in the number. Compliance is required as indicated, unless already accomplished. To prevent the tow-hook knob from dropping into the control stick boot during flight and obstructing control stick movement, accomplish the following: (a) If the guide-sleeve cut out is located at the bottom left hand (LH) corner of the instrument panel, as shown in Fig. 1 and Fig. 2 of Grob Service Bulletin (SB) TM 315-32, within the next 10 hours time-in-service after the effective date of this AD, visually inspect the aft tow- hook knob in the area of the guide sleeve for wear, cracks or looseness of the tow-hook knob. (b) If wear, cracked sleeve or looseness is determined, before further flight, unless already accomplished, relocate the position of tow-hook knob in accordance with Instruction 2 in Grob SB TM 315-32, dated June 12, 1987. (c) If the inspection of (a) determines that no wear, crack or looseness of any part in the tow-hook knob exist, accomplish the relocation of the knob as indicated in (b) within the next 20 hours time-in-service after the effective date of this AD. (d) Upon request, an equivalent means of compliance with the requirements of this AD may be approved by the Manager, Brussels Aircraft Certification Office, AEU-100, Europe, Africa, and Middle East Office, FAA, c/o American Embassy, 15 Rue de la Loi B-1040 Brussels, Belgium, Telephone No. 513.38.30 ext. 2710 or the Manager, New York Aircraft Certification Office, Aircraft Certification Division, Federal Aviation Administration, New England Region, 181 South Franklin Avenue, Room 202, Valley Stream, New York 11581; telephone (516) 791- 6680. (e) Upon submission of substantiating data by an owner or operator through an FAA maintenance inspector, the Manager, Brussels Aircraft Certification Office or the Manager, New York Aircraft Certification Office, may adjust the compliance time specified in this AD. Grob SB TM 315-32, dated June 12, 1987, identified and described in this document, is incorporated herein and made a part hereof pursuant to 5 U.S.C. 552(a)(1). All persons affected by this directive who have not already received this document from the manufacturer may obtain copies upon request to Grob Systems, Inc., Aircraft Division, I-75 and Airport Drive, Bluffton, Ohio 45817. These documents may also be examined at the Office of the Regional Counsel, Federal Aviation Administration, New England Region, 12 New England Executive Park, Burlington, Massachusetts 01803, Room 311, Rules Docket 88-ANE-15, between the hours of 8:00 a.m. and 4:30 p.m., Monday thru Friday, except federal holidays. This amendment, 39-5915, becomes effective on June 9, 1988. ## Affected data sheets (1) (OpenAirDocs) The type certificate data sheets whose models the AD names. - [TCDS G39EU](https://openairdocs.org/tcds/G39EU): Fiberglas-Technik Rudolf Lindner GmbH & Co. KG; names 3 of 4 models: G103 Twin Astir, G103A Twin II Acro, G103 Twin II ## Registered aircraft it may apply to (OpenAirDocs) Matched by airframe and engine model; the AD's applicability may narrow it by serial number, part number or equipment. - Aircraft: 95 (95 by airframe model, 0 by engine model) - Makers: Burkhart Grob 60, Burkhart Grob Flugzeugbau 35 Models with the most aircraft: - [Burkhart Grob Flugzeugbau G103 TWIN ASTIR](https://openairdocs.org/model/burkhart-grob-flugzeugbau-g103-twin-astir): 35 aircraft (airframe model) - [Burkhart Grob G 103 TWIN II](https://openairdocs.org/model/burkhart-grob-g-103-twin-ii): 30 aircraft (airframe model) - [Burkhart Grob G-103A TWIN II ACRO](https://openairdocs.org/model/burkhart-grob-g-103a-twin-ii-acro): 26 aircraft (airframe model) - [Burkhart Grob G103 TWIN ASTIR](https://openairdocs.org/model/burkhart-grob-g103-twin-astir): 4 aircraft (airframe model) All 4 models: https://openairdocs.org/ad/88-12-08/models.md Every aircraft: https://openairdocs.org/ad/88-12-08/aircraft.md Its text cites no advisory circulars or STCs. --- OpenAirDocs.org is an independent research project of [Contrail Labs](https://contraillabs.com/). It is not affiliated with the FAA or the NTSB. Source documents are U.S. government works in the public domain.