- Models
- 188A, 188C
- Data sheet
- TCDS4A22
- Registered aircraft
- 4 matched by model
- Product
- Aircraft · Large airplane
Unofficial copy of the text in the FAA’s Dynamic Regulatory System. The FAA’s own copy is the authoritative one. DRS record last changed May 30, 2024.
Copies of the files this page was built from, with their SHA-256. Retrieved October 18, 2026.
| File | Size | SHA-256 | Original |
|---|---|---|---|
| FAA DRS HTML | 20 KB | a42ae8cb…edef91f | FAA DRS (API key needed) |
On this page
The airworthiness directive
59-21-02 LOCKHEED: Applies to All Model 188 Series Aircraft.
Compliance required as indicated.
Due to repeated loosening of wing leading edge attachment screws between the fuselage and the outboard nacelles, the following inspections shall be conducted:
(a) At each 50 hours of service time, visually inspect the leading edge attachment screws, top and bottom, from the fuselage to the outboard nacelles, paying particular attention to screws adjacent to nacelles. Tighten any screws found loose.
(b) At 300-hour intervals retighten all affected screws to 25 to 40 inch-pounds torque.
The above inspection program may be discontinued upon the removal of the NAS 517-3 screws from all leading edge attachments, top and bottom, and the installation of LPHT 517-3 screws. Torque all new leading edge attaching screws to 45-55 inch-pounds.
(Lockheed Service Bulletin 88/SB-334 covers this same subject.)
NOTE: LPHT-517 refers to Lockheed Specification for a Long-Lok, Polyvinyl insert, High torque screw.
Affected TCDS · 1
The type certificate data sheets for the models this AD names, matched by model and maker.
Registered aircraft · 4
Registered aircraft whose airframe or engine model this AD names. Matched by model only, so check each against the AD’s applicability.
| 1959 | 2 |
|---|---|
| 1960 | 1 |
1 with no year recorded