AD 77-21-03
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| aircraft | Piper Aircraft Inc. | PA-36-285 | Airworthiness Directives; Piper Model PA-36-285 Airplanes |
Unsafe Condition
Rudder spar cracks at hinge attachment points could cause hazards in flight.
AI-generated summary from the source AD text. Verify against the official source before acting.
Required Actions
Inspect the rudder spar at hinge attachment points for cracks using a magnifying glass of at least ten power within the next 50 hours in service from the effective date. If cracks exist, replace the rudder assembly with a new Piper Part No. 98125-04 or equivalent. After installing the new rudder assembly, compliance with this AD may be dispensed with.
AI-generated summary from the source AD text. Verify against the official source before acting.
Compliance Time
Within the next 50 hours in service from the effective date of this AD unless previously accomplished within the past 50 hours in service and at intervals not to exceed 100 hours in service from the last inspection.
AI-generated summary from the source AD text. Verify against the official source before acting.
Affected Aircraft
Piper Aircraft Inc. Model PA-36-285, Serial Nos. 36-7360001 through 36-7760003 certificated in all categories.
AI-generated summary from the source AD text. Verify against the official source before acting.
Federal Register Abstract
Rudder Spar Cracks
Applicability Source Text
Show captured applicability text from the source AD
AD Final Rules - DRS_77-21-03.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 77-21-03 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: Airworthiness Directives; Piper Model PA-36-285 Airplanes Subject: Rudder Spar Cracks Status: Current Citation: This information is not available. Citation Publish Date: 10/13/1977 Effective Date: 10/18/1977 Make: Piper Aircraft Inc. Model: PA-36-285 Product Type: Aircraft Product Subtype: Small Airplane Affected AD: Superseded AD: Affected By: Superseded By: Service/Office: AIR-700: Compliance & Airworthiness Division Office of Primary Responsibility: AIR-720: Operational Safety Branch CFR Part Reference: Part 39 Comments: AIRWORTHINESS DIRECTIVES FINAL RULES: 77-21-03 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: 39-3056 AD NUMBER: 77-21-03 SUBJECT HEADING: Airworthiness Directives; Piper Model PA-36-285 Airplanes ACTION: SUMMARY: DATES: Effective October 18, 1977. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 77-21-03 PIPER: Amendment 39-3056. Applies to Model PA-36-285, Serial Nos. 36-7360001 through 36-7760003 certificated in all categories. To prevent hazards in flight associated with rudder spar cracks, accomplish the following: (a) Within the next 50 hours in service from the effective date of this AD unless previously accomplished within the past 50 hours in service and at intervals not to exceed 100 hours in service from the last inspection, inspect the rudder spar at hinge attachment points for cracks using a magnifying glass of at least ten power. (b) If cracks exist replace the rudder assembly with a new rudder assembly Piper Part No. 98125-04 or equivalent. (c) Upon the incorporation of rudder assembly, Piper Part No. 98125-04 or equivalent, compliance with the requirements of this AD may be dispensed with. (d) Equivalent inspection and repairs must be approved by the Chief, Engineering and Manufacturing Branch, FAA, Eastern Region. (e) Upon submission of substantiating data by an owner or operator through an FAA Maintenance Inspector, the Chief, Engineering and Manufacturing Branch, FAA, Eastern Region may adjust the inspection intervals specified in this AD. (Piper Service Bulletin No. 518 refers to this subject.) This amendment is effective October 18, 1977. FOOTER:
Document Text
Show stored source text (verify against official source)
AD Final Rules - DRS_77-21-03.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 77-21-03 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: Airworthiness Directives; Piper Model PA-36-285 Airplanes Subject: Rudder Spar Cracks Status: Current Citation: This information is not available. Citation Publish Date: 10/13/1977 Effective Date: 10/18/1977 Make: Piper Aircraft Inc. Model: PA-36-285 Product Type: Aircraft Product Subtype: Small Airplane Affected AD: Superseded AD: Affected By: Superseded By: Service/Office: AIR-700: Compliance & Airworthiness Division Office of Primary Responsibility: AIR-720: Operational Safety Branch CFR Part Reference: Part 39 Comments: AIRWORTHINESS DIRECTIVES FINAL RULES: 77-21-03 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: 39-3056 AD NUMBER: 77-21-03 SUBJECT HEADING: Airworthiness Directives; Piper Model PA-36-285 Airplanes ACTION: SUMMARY: DATES: Effective October 18, 1977. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 77-21-03 PIPER: Amendment 39-3056. Applies to Model PA-36-285, Serial Nos. 36-7360001 through 36-7760003 certificated in all categories. To prevent hazards in flight associated with rudder spar cracks, accomplish the following: (a) Within the next 50 hours in service from the effective date of this AD unless previously accomplished within the past 50 hours in service and at intervals not to exceed 100 hours in service from the last inspection, inspect the rudder spar at hinge attachment points for cracks using a magnifying glass of at least ten power. (b) If cracks exist replace the rudder assembly with a new rudder assembly Piper Part No. 98125-04 or equivalent. (c) Upon the incorporation of rudder assembly, Piper Part No. 98125-04 or equivalent, compliance with the requirements of this AD may be dispensed with. (d) Equivalent inspection and repairs must be approved by the Chief, Engineering and Manufacturing Branch, FAA, Eastern Region. (e) Upon submission of substantiating data by an owner or operator through an FAA Maintenance Inspector, the Chief, Engineering and Manufacturing Branch, FAA, Eastern Region may adjust the inspection intervals specified in this AD. (Piper Service Bulletin No. 518 refers to this subject.) This amendment is effective October 18, 1977. FOOTER:
Source: Official FAA Source ↗
Retrieved: Apr 8, 2026
Rights: U.S. Government Public Domain
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