AD 91-02-04
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| aircraft | Burkhart Grob Luft-Und | G103 Twin Astir | Airworthiness Directives; GROB WERKE GMBH & CO. KG (GROB) Models G103 "Twin Astir" (including "Trainer") and G103 "Twin II" (including "ACRO") Gliders |
| aircraft | Burkhart Grob Luft-Und | G103 Twin II | Airworthiness Directives; GROB WERKE GMBH & CO. KG (GROB) Models G103 "Twin Astir" (including "Trainer") and G103 "Twin II" (including "ACRO") Gliders |
| aircraft | Burkhart Grob Luft-Und | G103A Twin II Acro | Airworthiness Directives; GROB WERKE GMBH & CO. KG (GROB) Models G103 "Twin Astir" (including "Trainer") and G103 "Twin II" (including "ACRO") Gliders |
Unsafe Condition
The incorrect installation of the aileron system connecting bolt could lead to a failure of the aileron control system.
AI-generated summary from the source AD text. Verify against the official source before acting.
Required Actions
Install GROB forkhead nut (part number 103B-4229), remove the caution placard on the aileron control lever adjacent to the connecting bolt, as per GROB Service Bulletin No. TM 315-38/1.
AI-generated summary from the source AD text. Verify against the official source before acting.
Compliance Time
within the next 50 hours time-in-service after the effective date of this AD
AI-generated summary from the source AD text. Verify against the official source before acting.
Affected Aircraft
GROB Models G103 Twin Astir (including Trainer) gliders (S/N 3000 through 3291) and G103 Twin II (including ACRO) gliders (S/N 3501 through 3729)
AI-generated summary from the source AD text. Verify against the official source before acting.
Federal Register Abstract
Aileron Control System
Applicability Source Text
Show captured applicability text from the source AD
AD Final Rules - DRS_91-02-04.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 91-02-04 Document Type: AD Final Rules Docket Number: 90-CE-29-AD Subject Heading: Airworthiness Directives; GROB WERKE GMBH & CO. KG (GROB) Models G103 "Twin Astir" (including "Train...Show more Subject: Aileron Control System Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 02/08/1991 Make: Burkhart Grob Luft-Und Model: G103 Twin Astir | G103 Twin II | G103A Twin II Acro Product Type: Aircraft Product Subtype: Glider Affected AD: Superseded AD: Affected By: Superseded By: Service/Office: Office of Primary Responsibility: CFR Part Reference: Part 39 Comments: Updated RGL applicability to match AD applicability; CAR C-11-185 AIRWORTHINESS DIRECTIVES FINAL RULES: 91-02-04 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: 90-CE-29-AD AMENDMENT: 39-6823 AD NUMBER: 91-02-04 SUBJECT HEADING: Airworthiness Directives; GROB WERKE GMBH & CO. KG (GROB) Models G103 "Twin Astir" (including "Trainer") and G103 "Twin II" (including "ACRO") Gliders ACTION: SUMMARY: DATES: Effective February 8, 1991. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 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 that provides 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. FOOTER:
Document Text
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AD Final Rules - DRS_91-02-04.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 91-02-04 Document Type: AD Final Rules Docket Number: 90-CE-29-AD Subject Heading: Airworthiness Directives; GROB WERKE GMBH & CO. KG (GROB) Models G103 "Twin Astir" (including "Train...Show more Subject: Aileron Control System Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 02/08/1991 Make: Burkhart Grob Luft-Und Model: G103 Twin Astir | G103 Twin II | G103A Twin II Acro Product Type: Aircraft Product Subtype: Glider Affected AD: Superseded AD: Affected By: Superseded By: Service/Office: Office of Primary Responsibility: CFR Part Reference: Part 39 Comments: Updated RGL applicability to match AD applicability; CAR C-11-185 AIRWORTHINESS DIRECTIVES FINAL RULES: 91-02-04 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: 90-CE-29-AD AMENDMENT: 39-6823 AD NUMBER: 91-02-04 SUBJECT HEADING: Airworthiness Directives; GROB WERKE GMBH & CO. KG (GROB) Models G103 "Twin Astir" (including "Trainer") and G103 "Twin II" (including "ACRO") Gliders ACTION: SUMMARY: DATES: Effective February 8, 1991. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 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 that provides 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. FOOTER:
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Retrieved: Apr 8, 2026
Rights: U.S. Government Public Domain
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