# AD 91-02-04: Aileron Control System

- Type: Airworthiness directive
- Status: Current
- Products: Burkhart Grob Luft-Und G103 Twin Astir, G103 Twin II and G103A Twin II Acro
- Effective: February 8, 1991
- Superseded by: Nothing supersedes this AD
- Product type: Aircraft, Glider
- Amendment: 39-6823
- Docket: 90-CE-29-AD
- Registered aircraft: 95 may be affected, by airframe or engine model (OpenAirDocs)
- FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/18DC5B55FEB657D386256A4D006DE898.0001
- DRS record last changed: May 30, 2024
- Page: https://openairdocs.org/ad/91-02-04

## The airworthiness directive

91-02-04 GROB WERKE GMBH & CO. KG (GROB): Amendment 39-6823; Docket No. 90-CE-29-AD.

Applicability: Models G103 "Twin Astir" (including "Trainer") gliders (Serial Numbers (S/N) 3000 through 3291) and G103 "Twin II" (including "ACRO") gliders (S/N 3501 through 3729), certificated in any category.

Compliance: Required within the next 50 hours time-in-service after the effective date of this AD, unless already accomplished.

To preclude the incorrect installation of the aileron system connecting bolt, accomplish the following:

  (a) Modify the aileron control system by installing a GROB forkhead nut (GROB part number 103B-4229) and removing the placard that cautions against incorrect installation of the connecting bolts located on the aileron control lever adjacent to the connecting bolt, if installed, as described in GROB Service Bulletin No. TM 315-38/1, dated December 12, 1989.

  (b) An alternate method of compliance or adjustment of the compliance time thatprovides an equivalent level of safety may be approved by the Manager, Brussels Aircraft Certification Staff, Europe, Africa, and Middle East Office, FAA, c/o American Embassy, B-1000 Brussels, Belgium; Telephone (322) 513.38.30 ext. 2718; Facsimile (322) 230.68.99. The request should be forwarded through an appropriate FAA Maintenance Inspector, who may add comments and then send it to the Manager, Brussels Aircraft Certification Staff.

  (c) All persons affected by this directive may obtain copies of the document referred to herein upon request to GROB Systems, Incorporated; Aircraft Division, I-75 and Airport Drive, Bluffton, Ohio 45817; Telephone (419) 358-9015; or may examine this document at the FAA, Central Region, Office of the Assistant Chief Counsel, Room 1558, 601 E. 12th Street, Kansas City, Missouri 64106.

This amendment (39-6823, AD 91-02-04) becomes effective on February 8, 1991.

## 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/91-02-04/models.md
Every aircraft: https://openairdocs.org/ad/91-02-04/aircraft.md

Its text cites no advisory circulars or STCs.

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