AD 91-12-06
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| aircraft | Burkhart Grob Luft-Und | GROB G 109B | Airworthiness Directives; GROB LUFT UND RAUMFAHRT Model G 109B Motor Gliders |
Unsafe Condition
Separation of the studs in the root rib stud plate (part number 109B-4108) could result in loss of the aileron and airbrake control systems.
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Required Actions
Inspect the security of the studs in the root rib stud plate (part number 109B-4108) per GROB Service Bulletin No. TM-817-29. If loose studs are found, repair the stud plate prior to further flight. Special flight permits may be issued under FAR 21.197 and 21.199 to operate to a repair location.
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Compliance Time
within the next 3 calendar months after the effective date of this AD, unless already accomplished
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Affected Aircraft
GROB LUFT UND RAUMFAHRT Model G 109B motor gliders (serial numbers 6200 through 6362)
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Federal Register Abstract
Rib Stud Plate
Applicability Source Text
Show captured applicability text from the source AD
AD Final Rules - DRS_91-12-06.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 91-12-06 Document Type: AD Final Rules Docket Number: 91-CE-05-AD Subject Heading: Airworthiness Directives; GROB LUFT UND RAUMFAHRT Model G 109B Motor Gliders Subject: Rib Stud Plate Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 07/05/1991 Make: Burkhart Grob Luft-Und Model: GROB G 109B Product Type: Aircraft Product Subtype: Glider Affected AD: Superseded AD: Affected By: Superseded By: Service/Office: Office of Primary Responsibility: CFR Part Reference: Part 39 Comments: AIRWORTHINESS DIRECTIVES FINAL RULES: 91-12-06 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: 91-CE-05-AD AMENDMENT: 39-7017 AD NUMBER: 91-12-06 SUBJECT HEADING: Airworthiness Directives; GROB LUFT UND RAUMFAHRT Model G 109B Motor Gliders ACTION: SUMMARY: DATES: Effective July 5, 1991. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 91-12-06 GROB LUFT UND RAUMFAHRT: Amendment 39-7017. Docket No. 91- CE-05-AD. Applicability: Model G 109B motor gliders (serial numbers 6200 through 6362), certificated in any category. Compliance: Required within the next 3 calendar months after the effective date of this AD, unless already accomplished. To prevent separation of the studs in the root rib stud plate that could result in loss of the aileron and airbrake control systems, accomplish the following: (a) Inspect the security of the studs in the root rib stud plate (part number 109B- 4108) in accordance with the instructions in GROB Service Bulletin No. TM-817-29, dated August 6, 1990. If any loose studs are found, prior to further flight, repair the stud plate in accordance with the instructions in the referenced SB. (b) Special flight permits may be issued in accordance with FAR 21.197 and 21.199 to operate the motor glider to a location where the requirements of this AD can be accomplished. (c) An alternative 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 Office, Europe, Africa, and Middle East Office, FAA, c/o American Embassy, B- 1000 Brussels, Belgium; Telephone (322) 513.38.30. 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 Office. (d) All persons affected by this directive may obtain copies of the document discussed in this AD upon request to GROB Luft und Raumfahrt, D-8939 Mattsies, Federal Republic of Germany; 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 (39-7017, AD 91-12-06) becomes effective on July 5, 1991. FOOTER:
Document Text
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AD Final Rules - DRS_91-12-06.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 91-12-06 Document Type: AD Final Rules Docket Number: 91-CE-05-AD Subject Heading: Airworthiness Directives; GROB LUFT UND RAUMFAHRT Model G 109B Motor Gliders Subject: Rib Stud Plate Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 07/05/1991 Make: Burkhart Grob Luft-Und Model: GROB G 109B 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: AIRWORTHINESS DIRECTIVES FINAL RULES: 91-12-06 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: 91-CE-05-AD AMENDMENT: 39-7017 AD NUMBER: 91-12-06 SUBJECT HEADING: Airworthiness Directives; GROB LUFT UND RAUMFAHRT Model G 109B Motor Gliders ACTION: SUMMARY: DATES: Effective July 5, 1991. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 91-12-06 GROB LUFT UND RAUMFAHRT: Amendment 39-7017. Docket No. 91- CE-05-AD. Applicability: Model G 109B motor gliders (serial numbers 6200 through 6362), certificated in any category. Compliance: Required within the next 3 calendar months after the effective date of this AD, unless already accomplished. To prevent separation of the studs in the root rib stud plate that could result in loss of the aileron and airbrake control systems, accomplish the following: (a) Inspect the security of the studs in the root rib stud plate (part number 109B- 4108) in accordance with the instructions in GROB Service Bulletin No. TM-817-29, dated August 6, 1990. If any loose studs are found, prior to further flight, repair the stud plate in accordance with the instructions in the referenced SB. (b) Special flight permits may be issued in accordance with FAR 21.197 and 21.199 to operate the motor glider to a location where the requirements of this AD can be accomplished. (c) An alternative 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 Office, Europe, Africa, and Middle East Office, FAA, c/o American Embassy, B- 1000 Brussels, Belgium; Telephone (322) 513.38.30. 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 Office. (d) All persons affected by this directive may obtain copies of the document discussed in this AD upon request to GROB Luft und Raumfahrt, D-8939 Mattsies, Federal Republic of Germany; 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 (39-7017, AD 91-12-06) becomes effective on July 5, 1991. FOOTER:
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Retrieved: Apr 8, 2026
Rights: U.S. Government Public Domain
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