Type Record · As of May 3, 2026
HILLER OH-23G
Rotorcraft
Registered
4
Year Range
1962–1964
NTSB Events
4
Airworthiness Directives
3
01 / Distribution
Where the fleet lives and was built
Counts of currently-registered HILLER OH-23G aircraft by US state and decade of manufacture, sourced from the FAA Aircraft Registry.
By State (top 10)
- TX 50.0% 2
- KS 25.0% 1
- MT 25.0% 1
By Decade of Manufacture
- 1960s 75.0% 3
- Unknown 25.0% 1
02 / NTSB Records
Events involving HILLER OH-23G aircraft
4 event(s) on file. Showing the most recent 4.
-
Jun 23, 2011
N99579Hanford, California
NTSB Docket → -
Apr 19, 1983
N62409NEAR NORDM, Idaho
NTSB Docket → -
May 30, 1981
N62409ORLEANS, California
NTSB Docket → -
Sep 27, 1976
N62409CLARK FORK, Idaho
NTSB Docket →
03 / Airworthiness Directives
FAA directives applicable to HILLER OH-23G
3 directive(s) on file. Showing the most recent 3.
-
Aug 20, 2025
Airworthiness Directives; Siam Hiller Holdings, Inc.
The FAA is adopting a new airworthiness directive (AD) for certain Siam Hiller Holdings, Inc. (Siam Hiller), Model UH-12E (Army OH-23G and H-23F) and UH-12E-L helicopters. This AD was prompted by reports of cracks found in a main rotor (M/R) transmission drive shaft (drive shaft). This AD requires inspecting certain M…
-
Jan 14, 2025
Airworthiness Directives; Siam Hiller Holdings, Inc, Helicopters
The FAA proposes to adopt a new airworthiness directive (AD) for Siam Hiller Holdings, Inc. (Siam Hiller), Model UH-12E (Army OH-23G and H-23F) and UH-12E-L helicopters. This proposed AD was prompted by reports of cracks found in a main rotor (M/R) transmission drive shaft (drive shaft). This proposed AD would require…
-
May 23, 1997
Airworthiness Directives; Hiller Aircraft Corporation Model UH- 12, UH-12A, UH-12B, UH-12C, UH-12D, UH-12E, CH-112, H-23A, H-23B, H- 23C, H-23D, H-23F, HTE-1, HTE-2, and OH-23G Helicopters
This amendment supersedes an existing airworthiness directive (AD), applicable to Hiller Aircraft Corporation Model UH-12, UH-12A, UH-12B, UH-12C, UH-12D, UH-12E, CH-112, H-23A, H-23B, H-23C, H-23D, H- 23F, HTE-1, HTE-2, and OH-23G helicopters, and UH-12D and UH-12E helicopters converted to turbine engine power in acc…
04 / Regulations watching this type
Advisory Circulars and Federal Register activity for HILLER OH-23G
Advisory Circulars
ACs whose subject explicitly mentions HILLER or OH-23G.
Recent Federal Register activity
Latest rulemakings touching general operating rules (Part 91) and maintenance rules (Part 43).
- 2026-04-17 Settlement Policy for Small Unmanned Aircraft System (UAS) Cases FR ↗
- 2026-02-10 Normalizing Unmanned Aircraft Systems Beyond Visual Line of Sight Operations; Reopening of Comment Period; Denial of Extension FR ↗
- 2026-02-02 25-Hour Cockpit Voice Recorder (CVR) Requirement, New Aircraft Production FR ↗
- 2026-01-28 Normalizing Unmanned Aircraft Systems Beyond Visual Line of Sight Operations; Reopening of Comment Period FR ↗
- 2026-01-07 Requirements for Interference-Tolerant Radio Altimeter Systems FR ↗
05 / Aircraft of this type
All 4 registered N-numbers
Every tail currently on the FAA registry for this make/model. Click an N-number to query the FAA Aircraft Inquiry; rows flagged ● have NTSB events on file. Tails seeded with full TallyAero pages link directly.
05 / Sources & Methodology
Every count traces back to a primary US-government source
- FAA Aircraft Registry →
Refreshed Apr 27, 2026
Available
- NTSB CAROL →
Refreshed Apr 27, 2026
Available
- Federal Register (FAA Airworthiness Directives) →
Refreshed Apr 27, 2026
Available
We render counts and lists as the agency publishes them. Read the methodology →