- Models
- H-391B, H-395 (USAF L-28A or U-10B)
- Data sheet
- TCDS1A8
- Registered aircraft
- 32 matched by model
- Product
- Aircraft · Small 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 | 19 KB | 607fbb9c…dd862ce | FAA DRS (API key needed) |
On this page
The airworthiness directive
58-25-04 HELIO: Applies to Models H-391B and H-395 Aircraft Incorporating Three Fin Hinge Attachments.
Compliance required not later than next 100 hours operation or March 31, 1959, whichever occurs first.
Failure of the fin upper hinge attachment has been reported. Accordingly, the following inspection and replacement programs are required:
Inspect the fin top hinge and attachment details. Cracked parts must be replaced; uncracked parts may be reinstalled. In any case, new reinforcement gussets (P/N 391-022-001-16) must be installed.
(Helio Service Bulletin No. 18 covers this subject.)
Affected TCDS · 1
The type certificate data sheets for the models this AD names, matched by model and maker.
Registered aircraft · 32
Registered aircraft whose airframe or engine model this AD names. Matched by model only, so check each against the AD’s applicability.
| 1954 | 1 |
|---|---|
| 1956 | 5 |
| 1957 | 3 |
| 1958 | 4 |
| 1959 | 2 |
| 1960 | 2 |
| 1962 | 4 |
| 1963 | 3 |
8 with no year recorded