AD 77-18-06
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| aircraft | The Boeing Company | 727-100 Series | BOEING Model 727 Series Airplanes |
| aircraft | The Boeing Company | 727-100C Series | BOEING Model 727 Series Airplanes |
| aircraft | The Boeing Company | 727-200 Series | BOEING Model 727 Series Airplanes |
| aircraft | The Boeing Company | 727-200F Series | BOEING Model 727 Series Airplanes |
| aircraft | The Boeing Company | 727 Series | BOEING Model 727 Series Airplanes |
| aircraft | The Boeing Company | 727C Series | BOEING Model 727 Series Airplanes |
Unsafe Condition
Cracks in the horizontal stabilizer center section front spar junction fittings, P/Ns 65-17448-1 or 65-31273-1, which could lead to structural failure.
AI-generated summary from the source AD text. Verify against the official source before acting.
Required Actions
Inspect the horizontal stabilizer center section front spar junction fittings for cracks using specified methods (eddy current or dye penetrant) with jackscrew support arms removed or installed as per Boeing Service Bulletin. Apply corrosion inhibitor to lugs. Repeat inspections at intervals of 1,500 flight hours or 9 months, or 3,000 flight hours or 18 months if reworked. Replace or repair cracked fittings before further flight. Report cracks within 64 hours. Replace with P/N 65-31273-4 to terminate AD.
AI-generated summary from the source AD text. Verify against the official source before acting.
Compliance Time
Within the next 750 flight hours time-in-service from the effective date (October 3, 1977) or prior to January 1, 1978, whichever occurs first.
AI-generated summary from the source AD text. Verify against the official source before acting.
Affected Aircraft
Boeing Model 727-100 Series, 727-100C Series, 727-200 Series, 727-200F Series, 727 Series, 727C Series with horizontal stabilizer center section front spar junction fittings P/Ns 65-17448-1 or 65-31273-1.
AI-generated summary from the source AD text. Verify against the official source before acting.
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.