AD 74-11-03
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| aircraft | Airesearch | Fokker Services | Gulfstream Aerospace Corporation | Mitsubishi Heavy Industries, Ltd. | VFW-Vereinigte Flugtechnische Werke, G.m.b.H. | Auxiliary Power Units | Airworthiness Directives; AIRESEARCH: Applies To Model GTCP36-4A, -6, -16, and -28 Auxiliary Power Units (APU) |
| aircraft | Airesearch | Fokker Services | Gulfstream Aerospace Corporation | Mitsubishi Heavy Industries, Ltd. | VFW-Vereinigte Flugtechnische Werke, G.m.b.H. | F.28 Mark 0070 | Airworthiness Directives; AIRESEARCH: Applies To Model GTCP36-4A, -6, -16, and -28 Auxiliary Power Units (APU) |
| aircraft | Airesearch | Fokker Services | Gulfstream Aerospace Corporation | Mitsubishi Heavy Industries, Ltd. | VFW-Vereinigte Flugtechnische Werke, G.m.b.H. | F.28 Mark 0100 | Airworthiness Directives; AIRESEARCH: Applies To Model GTCP36-4A, -6, -16, and -28 Auxiliary Power Units (APU) |
| aircraft | Airesearch | Fokker Services | Gulfstream Aerospace Corporation | Mitsubishi Heavy Industries, Ltd. | VFW-Vereinigte Flugtechnische Werke, G.m.b.H. | F.28 Mark 1000 | Airworthiness Directives; AIRESEARCH: Applies To Model GTCP36-4A, -6, -16, and -28 Auxiliary Power Units (APU) |
| aircraft | Airesearch | Fokker Services | Gulfstream Aerospace Corporation | Mitsubishi Heavy Industries, Ltd. | VFW-Vereinigte Flugtechnische Werke, G.m.b.H. | F.28 Mark 2000 | Airworthiness Directives; AIRESEARCH: Applies To Model GTCP36-4A, -6, -16, and -28 Auxiliary Power Units (APU) |
| aircraft | Airesearch | Fokker Services | Gulfstream Aerospace Corporation | Mitsubishi Heavy Industries, Ltd. | VFW-Vereinigte Flugtechnische Werke, G.m.b.H. | F.28 Mark 3000 | Airworthiness Directives; AIRESEARCH: Applies To Model GTCP36-4A, -6, -16, and -28 Auxiliary Power Units (APU) |
| aircraft | Airesearch | Fokker Services | Gulfstream Aerospace Corporation | Mitsubishi Heavy Industries, Ltd. | VFW-Vereinigte Flugtechnische Werke, G.m.b.H. | F.28 Mark 4000 | Airworthiness Directives; AIRESEARCH: Applies To Model GTCP36-4A, -6, -16, and -28 Auxiliary Power Units (APU) |
| aircraft | Airesearch | Fokker Services | Gulfstream Aerospace Corporation | Mitsubishi Heavy Industries, Ltd. | VFW-Vereinigte Flugtechnische Werke, G.m.b.H. | G-1159 | Airworthiness Directives; AIRESEARCH: Applies To Model GTCP36-4A, -6, -16, and -28 Auxiliary Power Units (APU) |
| aircraft | Airesearch | Fokker Services | Gulfstream Aerospace Corporation | Mitsubishi Heavy Industries, Ltd. | VFW-Vereinigte Flugtechnische Werke, G.m.b.H. | G-1159A | Airworthiness Directives; AIRESEARCH: Applies To Model GTCP36-4A, -6, -16, and -28 Auxiliary Power Units (APU) |
| aircraft | Airesearch | Fokker Services | Gulfstream Aerospace Corporation | Mitsubishi Heavy Industries, Ltd. | VFW-Vereinigte Flugtechnische Werke, G.m.b.H. | G-1159B | Airworthiness Directives; AIRESEARCH: Applies To Model GTCP36-4A, -6, -16, and -28 Auxiliary Power Units (APU) |
| appliance | Airesearch | Fokker Services | Gulfstream Aerospace Corporation | Mitsubishi Heavy Industries, Ltd. | VFW-Vereinigte Flugtechnische Werke, G.m.b.H. | Auxiliary Power Units | Airworthiness Directives; AIRESEARCH: Applies To Model GTCP36-4A, -6, -16, and -28 Auxiliary Power Units (APU) |
| appliance | Airesearch | Fokker Services | Gulfstream Aerospace Corporation | Mitsubishi Heavy Industries, Ltd. | VFW-Vereinigte Flugtechnische Werke, G.m.b.H. | F.28 Mark 0070 | Airworthiness Directives; AIRESEARCH: Applies To Model GTCP36-4A, -6, -16, and -28 Auxiliary Power Units (APU) |
| appliance | Airesearch | Fokker Services | Gulfstream Aerospace Corporation | Mitsubishi Heavy Industries, Ltd. | VFW-Vereinigte Flugtechnische Werke, G.m.b.H. | F.28 Mark 0100 | Airworthiness Directives; AIRESEARCH: Applies To Model GTCP36-4A, -6, -16, and -28 Auxiliary Power Units (APU) |
| appliance | Airesearch | Fokker Services | Gulfstream Aerospace Corporation | Mitsubishi Heavy Industries, Ltd. | VFW-Vereinigte Flugtechnische Werke, G.m.b.H. | F.28 Mark 1000 | Airworthiness Directives; AIRESEARCH: Applies To Model GTCP36-4A, -6, -16, and -28 Auxiliary Power Units (APU) |
| appliance | Airesearch | Fokker Services | Gulfstream Aerospace Corporation | Mitsubishi Heavy Industries, Ltd. | VFW-Vereinigte Flugtechnische Werke, G.m.b.H. | F.28 Mark 2000 | Airworthiness Directives; AIRESEARCH: Applies To Model GTCP36-4A, -6, -16, and -28 Auxiliary Power Units (APU) |
| appliance | Airesearch | Fokker Services | Gulfstream Aerospace Corporation | Mitsubishi Heavy Industries, Ltd. | VFW-Vereinigte Flugtechnische Werke, G.m.b.H. | F.28 Mark 3000 | Airworthiness Directives; AIRESEARCH: Applies To Model GTCP36-4A, -6, -16, and -28 Auxiliary Power Units (APU) |
| appliance | Airesearch | Fokker Services | Gulfstream Aerospace Corporation | Mitsubishi Heavy Industries, Ltd. | VFW-Vereinigte Flugtechnische Werke, G.m.b.H. | F.28 Mark 4000 | Airworthiness Directives; AIRESEARCH: Applies To Model GTCP36-4A, -6, -16, and -28 Auxiliary Power Units (APU) |
| appliance | Airesearch | Fokker Services | Gulfstream Aerospace Corporation | Mitsubishi Heavy Industries, Ltd. | VFW-Vereinigte Flugtechnische Werke, G.m.b.H. | G-1159 | Airworthiness Directives; AIRESEARCH: Applies To Model GTCP36-4A, -6, -16, and -28 Auxiliary Power Units (APU) |
| appliance | Airesearch | Fokker Services | Gulfstream Aerospace Corporation | Mitsubishi Heavy Industries, Ltd. | VFW-Vereinigte Flugtechnische Werke, G.m.b.H. | G-1159A | Airworthiness Directives; AIRESEARCH: Applies To Model GTCP36-4A, -6, -16, and -28 Auxiliary Power Units (APU) |
| appliance | Airesearch | Fokker Services | Gulfstream Aerospace Corporation | Mitsubishi Heavy Industries, Ltd. | VFW-Vereinigte Flugtechnische Werke, G.m.b.H. | G-1159B | Airworthiness Directives; AIRESEARCH: Applies To Model GTCP36-4A, -6, -16, and -28 Auxiliary Power Units (APU) |
| appliance | Airesearch | Fokker Services | Gulfstream Aerospace Corporation | Mitsubishi Heavy Industries, Ltd. | VFW-Vereinigte Flugtechnische Werke, G.m.b.H. | YS-11 | Airworthiness Directives; AIRESEARCH: Applies To Model GTCP36-4A, -6, -16, and -28 Auxiliary Power Units (APU) |
| appliance | Airesearch | Fokker Services | Gulfstream Aerospace Corporation | Mitsubishi Heavy Industries, Ltd. | VFW-Vereinigte Flugtechnische Werke, G.m.b.H. | YS-11A-200 | Airworthiness Directives; AIRESEARCH: Applies To Model GTCP36-4A, -6, -16, and -28 Auxiliary Power Units (APU) |
| appliance | Airesearch | Fokker Services | Gulfstream Aerospace Corporation | Mitsubishi Heavy Industries, Ltd. | VFW-Vereinigte Flugtechnische Werke, G.m.b.H. | YS-11A-300 | Airworthiness Directives; AIRESEARCH: Applies To Model GTCP36-4A, -6, -16, and -28 Auxiliary Power Units (APU) |
| appliance | Airesearch | Fokker Services | Gulfstream Aerospace Corporation | Mitsubishi Heavy Industries, Ltd. | VFW-Vereinigte Flugtechnische Werke, G.m.b.H. | YS-11A-500 | Airworthiness Directives; AIRESEARCH: Applies To Model GTCP36-4A, -6, -16, and -28 Auxiliary Power Units (APU) |
| appliance | Airesearch | Fokker Services | Gulfstream Aerospace Corporation | Mitsubishi Heavy Industries, Ltd. | VFW-Vereinigte Flugtechnische Werke, G.m.b.H. | YS-11A-600 | Airworthiness Directives; AIRESEARCH: Applies To Model GTCP36-4A, -6, -16, and -28 Auxiliary Power Units (APU) |
| appliance | Airesearch | Fokker Services | Gulfstream Aerospace Corporation | Mitsubishi Heavy Industries, Ltd. | VFW-Vereinigte Flugtechnische Werke, G.m.b.H. | VFW-614 | Airworthiness Directives; AIRESEARCH: Applies To Model GTCP36-4A, -6, -16, and -28 Auxiliary Power Units (APU) |
Unsafe Condition
Manufacturing error resulting in a certain lot of fuel controls for the APU containing a case casting wall thickness below allowable design limits. Failure of the wall would allow H.P. fuel to leak into the APU compartment.
AI-generated summary from the source AD text. Verify against the official source before acting.
Required Actions
Within 25 hours additional time in service, visually inspect the APU fuel control body per AiResearch Alert Service Bulletins. If unacceptable wall thickness is found, either placard the APU inoperative until replaced or replace with a new/serviceable part. Mark unacceptable units, return to AiResearch, re-identify acceptable units, and log entries.
AI-generated summary from the source AD text. Verify against the official source before acting.
Compliance Time
Within 25 hours additional time in service
AI-generated summary from the source AD text. Verify against the official source before acting.
Affected Aircraft
AiResearch Model GTCP36-4A, -6, -16, and -28 Auxiliary Power Units (APU) installed on Grumman Gulfstream 1159, Fokker F-28, NAMC YS-11, and VFW Fokker 614 aircraft.
AI-generated summary from the source AD text. Verify against the official source before acting.
Federal Register Abstract
Auxiliary Power Units
Applicability Source Text
Show captured applicability text from the source AD
AD Final Rules - DRS_74-11-03.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 74-11-03 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: Airworthiness Directives; AIRESEARCH: Applies To Model GTCP36-4A, -6, -16, and -28 Auxiliary Power...Show more Subject: Auxiliary Power Units Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 05/20/1974 Make: Airesearch | Fokker Services | Gulfstream Aerospace Corporation | Mitsubishi Heavy Industries, Ltd. ...Show more Model: Auxiliary Power Units | F.28 Mark 0070 | F.28 Mark 0100 | F.28 Mark 1000 | F.28 Mark 2000 | F.28 Mar...Show more Product Type: Appliance Product Subtype: Affected AD: Superseded AD: Affected By: Superseded By: Service/Office: Office of Primary Responsibility: CFR Part Reference: Part 39 Comments: AIRWORTHINESS DIRECTIVES FINAL RULES: 74-11-03 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: 39-1848 AD NUMBER: 74-11-03 SUBJECT HEADING: Airworthiness Directives; AIRESEARCH: Applies To Model GTCP36-4A, -6, -16, and -28 Auxiliary Power Units (APU) ACTION: SUMMARY: DATES: Effective May 20, 1974. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 74-11-03 AIRESEARCH: Amendment 39-1848. Applies to model GTCP36-4A, -6, -16, and -28 Auxiliary Power Units (APU) installed on, but not limited to, Grumman Gulfstream 1159, Fokker F-28, NAMC YS-11, and VFW Fokker 614 Aircraft. "Pursuant to the authority of the Federal Aviation Act of 1958, delegated to me by the Administrator (31 F.R. 13697), the following airworthiness directive applicable to all aircraft incorporating AiResearch Model GTCP36-4A, -6, -16, and -28 Auxiliary Power Units (APU), installed in, but not limited to, Grumman Gulfstream 1159, Fokker F-28, NAMC YS-11, and VFW Fokker 614 aircraft, listed in AiResearch Alert Service Bulletins GTCP36-49-A3621, dated March 19, 1974, and GTCP36-49-A3618, dated April 1, 1974, or later FAA-approved revisions, is effective immediately upon receipt of this airmail letter. This AD is required due to a manufacturing error resulting in a certain lot of fuel controls for the APU containing a case casting wall thickness below allowable design limits. As the vessel is a high pressure cavity, failure of the wall would allow H.P. fuel to leak into the APU compartment. Compliance required as indicated, unless already accomplished. Within 25 hours additional time in service of any aircraft on which the APU is installed, visually inspect the APU fuel control body per AiResearch Alert Service Bulletins GTCP36-49-A362l, dated March 19, 1974, or GTCP36-49-A3618, dated April 1, 1974, or later FAA-approved revisions. Prior to the installation of any AiResearch APU models listed herein, in any aircraft, conduct the visual inspection per the applicable Alert Service Bulletins. If, as a result of any of the foregoing inspections, fuel control units are found to have the unacceptable case casting wall thickness, either: (A) Prior to further flight, placard the APU inoperative until replaced with a new or serviceable part. The APU may not be operated until a new or serviceable part is installed. or (B) Replace, prior to further flight, with a new or serviceable part. Mark all fuel control units found to be unacceptable in a conspicuous manner to prevent inadvertent return to service. Return said units to AiResearch for exchange as indicated in the AiResearch Alert Service Bulletins. Re-identify acceptable units per the Alert Service Bulletins. Make appropriate aircraft logbook entries to reflect compliance with this AD. Aircraft may be flown to a base for performance of maintenance required by this AD, per FAR's 21.197 and 21.199, provided that the APU is inoperative for said flight." This amendment is effective May 20, 1974, for all persons except those to whom it was made effective immediately by airmail letter dated April 25, 1974. FOOTER:
Document Text
Show stored source text (verify against official source)
AD Final Rules - DRS_74-11-03.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 74-11-03 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: Airworthiness Directives; AIRESEARCH: Applies To Model GTCP36-4A, -6, -16, and -28 Auxiliary Power...Show more Subject: Auxiliary Power Units Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 05/20/1974 Make: Airesearch | Fokker Services | Gulfstream Aerospace Corporation | Mitsubishi Heavy Industries, Ltd. ...Show more Model: Auxiliary Power Units | F.28 Mark 0070 | F.28 Mark 0100 | F.28 Mark 1000 | F.28 Mark 2000 | F.28 Mar...Show more Product Type: Appliance Product Subtype: Affected AD: Superseded AD: Affected By: Superseded By: Service/Office: Office of Primary Responsibility: CFR Part Reference: Part 39 Comments: AIRWORTHINESS DIRECTIVES FINAL RULES: 74-11-03 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: 39-1848 AD NUMBER: 74-11-03 SUBJECT HEADING: Airworthiness Directives; AIRESEARCH: Applies To Model GTCP36-4A, -6, -16, and -28 Auxiliary Power Units (APU) ACTION: SUMMARY: DATES: Effective May 20, 1974. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 74-11-03 AIRESEARCH: Amendment 39-1848. Applies to model GTCP36-4A, -6, -16, and -28 Auxiliary Power Units (APU) installed on, but not limited to, Grumman Gulfstream 1159, Fokker F-28, NAMC YS-11, and VFW Fokker 614 Aircraft. "Pursuant to the authority of the Federal Aviation Act of 1958, delegated to me by the Administrator (31 F.R. 13697), the following airworthiness directive applicable to all aircraft incorporating AiResearch Model GTCP36-4A, -6, -16, and -28 Auxiliary Power Units (APU), installed in, but not limited to, Grumman Gulfstream 1159, Fokker F-28, NAMC YS-11, and VFW Fokker 614 aircraft, listed in AiResearch Alert Service Bulletins GTCP36-49-A3621, dated March 19, 1974, and GTCP36-49-A3618, dated April 1, 1974, or later FAA-approved revisions, is effective immediately upon receipt of this airmail letter. This AD is required due to a manufacturing error resulting in a certain lot of fuel controls for the APU containing a case casting wall thickness below allowable design limits. As the vessel is a high pressure cavity, failure of the wall would allow H.P. fuel to leak into the APU compartment. Compliance required as indicated, unless already accomplished. Within 25 hours additional time in service of any aircraft on which the APU is installed, visually inspect the APU fuel control body per AiResearch Alert Service Bulletins GTCP36-49-A362l, dated March 19, 1974, or GTCP36-49-A3618, dated April 1, 1974, or later FAA-approved revisions. Prior to the installation of any AiResearch APU models listed herein, in any aircraft, conduct the visual inspection per the applicable Alert Service Bulletins. If, as a result of any of the foregoing inspections, fuel control units are found to have the unacceptable case casting wall thickness, either: (A) Prior to further flight, placard the APU inoperative until replaced with a new or serviceable part. The APU may not be operated until a new or serviceable part is installed. or (B) Replace, prior to further flight, with a new or serviceable part. Mark all fuel control units found to be unacceptable in a conspicuous manner to prevent inadvertent return to service. Return said units to AiResearch for exchange as indicated in the AiResearch Alert Service Bulletins. Re-identify acceptable units per the Alert Service Bulletins. Make appropriate aircraft logbook entries to reflect compliance with this AD. Aircraft may be flown to a base for performance of maintenance required by this AD, per FAR's 21.197 and 21.199, provided that the APU is inoperative for said flight." This amendment is effective May 20, 1974, for all persons except those to whom it was made effective immediately by airmail letter dated April 25, 1974. FOOTER:
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