AD 78-26-11
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| aircraft | Piper Aircraft Inc. | PA-31-350 | Airworthiness Directives; Piper Model PA-31-350 Aircraft |
Unsafe Condition
The elevator control system may have restricted operation due to the lightening hole in the frame at Fuselage Station 87.50 interfering with the cable guide tube, and potential wear on the hydraulic line and elevator control cable tension issues.
AI-generated summary from the source AD text. Verify against the official source before acting.
Required Actions
Install Piper Part Number 71045-2 cable guide tube around the lightening hole at Fuselage Station 87.50, install nylon spiral sleeving around the hydraulic line, and adjust elevator control cable tension per Piper Service Bulletin 621 and the PA-31-350 Service Manual. Compliance may be done via an equivalent method approved by the FAA.
AI-generated summary from the source AD text. Verify against the official source before acting.
Compliance Time
within the next 25 hours of operation after the effective date of this AD
AI-generated summary from the source AD text. Verify against the official source before acting.
Affected Aircraft
Piper Model PA-31-350 Navajo Chieftain aircraft, Serial Numbers 31-5001 through 31-7852151
AI-generated summary from the source AD text. Verify against the official source before acting.
Federal Register Abstract
Elevator Control System
Applicability Source Text
Show captured applicability text from the source AD
AD Final Rules - DRS_78-26-11.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 78-26-11 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: Airworthiness Directives; Piper Model PA-31-350 Aircraft Subject: Elevator Control System Status: Current Citation: This information is not available. Citation Publish Date: 12/26/1978 Effective Date: 01/04/1979 Make: Piper Aircraft Inc. Model: PA-31-350 Product Type: Aircraft Product Subtype: Small Airplane Affected AD: Superseded AD: Affected By: Superseded By: Service/Office: AIR-700: Compliance & Airworthiness Division Office of Primary Responsibility: AIR-720: Operational Safety Branch CFR Part Reference: Part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: 78-26-11 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: 39-3380 AD NUMBER: 78-26-11 SUBJECT HEADING: Airworthiness Directives; Piper Model PA-31-350 Aircraft ACTION: SUMMARY: DATES: Effective January 4, 1979. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 78-26-11 PIPER AIRCRAFT CORPORATION: Amendment 39-3380. Applies to Piper PA-31-350 Navajo Chieftain aircraft, Serial Numbers 31-5001 through 31-7852151, certificated in all categories. Compliance required within the next 25 hours of operation after the effective date of this AD. To insure free operation of the elevator control system, accomplish the following: 1. Install cable guide tube, Piper Part Number 71045-2, around the lightening hole in the frame at Fuselage Station 87.50, in accordance with the "Instructions" section of Piper Service Bulletin 621, dated October 13, 1978, or later edition approved by the Chief, Engineering and Manufacturing Branch, FAA, Southern Region. 2. Install nylon spiral sleeving around hydraulic line in accordance with the above referenced instructions. 3. Adjust elevator control cable tension in accordance with the above referenced instructions and instructions contained in the Piper PA-31-350 Navajo Chieftain Service Manual. Compliance with the provisions of this AD may be accomplished in an equivalent manner approved by the Chief, Engineering and Manufacturing Branch, FAA, Southern Region. This amendment becomes effective January 4, 1979. FOOTER:
Document Text
Show stored source text (verify against official source)
AD Final Rules - DRS_78-26-11.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 78-26-11 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: Airworthiness Directives; Piper Model PA-31-350 Aircraft Subject: Elevator Control System Status: Current Citation: This information is not available. Citation Publish Date: 12/26/1978 Effective Date: 01/04/1979 Make: Piper Aircraft Inc. Model: PA-31-350 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: 78-26-11 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: 39-3380 AD NUMBER: 78-26-11 SUBJECT HEADING: Airworthiness Directives; Piper Model PA-31-350 Aircraft ACTION: SUMMARY: DATES: Effective January 4, 1979. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 78-26-11 PIPER AIRCRAFT CORPORATION: Amendment 39-3380. Applies to Piper PA-31-350 Navajo Chieftain aircraft, Serial Numbers 31-5001 through 31-7852151, certificated in all categories. Compliance required within the next 25 hours of operation after the effective date of this AD. To insure free operation of the elevator control system, accomplish the following: 1. Install cable guide tube, Piper Part Number 71045-2, around the lightening hole in the frame at Fuselage Station 87.50, in accordance with the "Instructions" section of Piper Service Bulletin 621, dated October 13, 1978, or later edition approved by the Chief, Engineering and Manufacturing Branch, FAA, Southern Region. 2. Install nylon spiral sleeving around hydraulic line in accordance with the above referenced instructions. 3. Adjust elevator control cable tension in accordance with the above referenced instructions and instructions contained in the Piper PA-31-350 Navajo Chieftain Service Manual. Compliance with the provisions of this AD may be accomplished in an equivalent manner approved by the Chief, Engineering and Manufacturing Branch, FAA, Southern Region. This amendment becomes effective January 4, 1979. FOOTER:
Source: Official FAA Source ↗
Retrieved: Apr 8, 2026
Rights: U.S. Government Public Domain
This site is not affiliated with or endorsed by the FAA. Always verify with official sources.
Related Airworthiness Directives
2023-09-09 Recurring
final ruleAirworthiness Directives; Various Airplanes, Helicopters, and Engines
Unsafe Condition: Multiple failures of spot-welded, multi-segment v-band couplings at the tailpipe to the turbocharger exhaust housing flange.
2017-10-20 Recurring
final ruleAirworthiness Directives; Piper Aircraft, Inc. Airplanes
Unsafe Condition: Fatigue cracking in the fuselage station (FS) 332.00 bulkhead common to the horizontal stabilizer front spar attachment.
2016-08-18
final ruleAirworthiness Directives; Piper Aircraft, Inc. Airplanes
Unsafe Condition: Engine fire caused by a leak in the fuel pump inlet hose.
2016-05-01 Recurring
final ruleAirworthiness Directives; Piper Aircraft, Inc. Airplanes
Unsafe Condition: Cracks in the fuselage station (FS) at 317.75 upper bulkhead, which could cause structural failure of the vertical fin forward spar and lead to loss of control.