Hiller UH-12E accident near Chickasha, Oklahoma, April 30, 2026
On April 30, 2026 at about 10:30 pm local time, a 1959 Hiller UH-12E (helicopter), registered N22SP, was substantially damaged in an accident during maneuvering (low-alt flying) near Chickasha, Oklahoma. It was an aerial application (crop spraying) flight under agricultural flying rules (Part 137). No one was hurt; 1 person was on board or involved. The weather was visual conditions (good weather).
The NTSB's probable cause their words, unchanged
The NTSB has not yet published a probable cause for this accident. Investigations usually take one to two years; this page updates when the final report is released.
Source: NTSB aviation accident database, copy made October 4, 2026. Docket and reports at the NTSB.
What the record shows
- Date
- April 30, 2026 · about 10:30 pm local time
- Place
- Chickasha, Oklahoma · map
- Type
- Accident
- Injuries
- No one was hurt; 1 person was on board or involved.
- Weather
- visual conditions (good weather)
- Aircraft
- Hiller UH-12E, built 1959 · all UH-12Es on the register
- Registration
- N22SP · registry record · serial 1214
- Damage
- Substantial damage
- Flight
- Aerial application (crop spraying) flight · agricultural flying rules (Part 137)
The NTSB's narrative preliminary · quoted from the NTSB record
On April 30, 2026, about 1730 central daylight time, a Hiller UH-12E, N22SP, was substantially damaged when it was involved in an accident near Chickasha, Oklahoma. The pilot was not injured. The helicopter was operated as a Title 14 Code of Federal Regulations Part 137 aerial application flight. The pilot reported that he had completed two aerial application flights earlier that day and performed preflight inspections before both. About 1700, he began spraying a field and during the flight, the main rotor “developed a vertical hop,” and he observed one of the control rotor blades separate from the helicopter. The helicopter violently shook, and he conducted a forced landing to a field. During the landing, the main rotor blades struck the tail boom, which severed the tail boom near the tail rotor. The responding FAA inspector and the pilot located the separated control rotor blade in the field about 100 yards from the accident site. A review of the FAA airworthiness directives (AD) indicated that AD 97-10-16 was applicable to the Hiller UH-12 helicopter. The AD required (in part) that the control rotor blade spar tube (or cuff) be inspected for corrosion or cracks, or elongation, corrosion, burrs, pitting or fretting of the bolt holes…during the annual inspection, not to exceed 100 hours and every 100-hours thereafter. The actions specified by the AD are intended to prevent separation of the control rotor blade assembly and subsequent loss of control of the helicopter. According to the helicopter maintenance records, an annual inspection was completed on February 20, 2026. During the inspection, the control rotor cuffs and trunnions were overhauled and reinstalled in accordance with the Hiller overhaul manual. The records show that AD 97-10-16 was complied with at this time. The separated control rotor was retained for further examination.
The complete narrative as the NTSB published it. The NTSB's docket holds the report as a PDF and any photographs, statements and other documents from the investigation.
The factual record from the NTSB's investigation tables, in plain English
What happened, in order
- Sys/Comp malf/fail (non-power) during maneuvering (low-alt flying) defining event
- Part(s) separation from AC during maneuvering (low-alt flying)
The aircraft
- Airframe total time: 8,033 hours
- Last inspection: annual inspection, February 20, 2026
- Maximum gross weight: 3,100 lb
- Seats: 3
- Landing gear: fixed
The flight
- Flight plan: none
Weather at the time
- Light: daylight
- Wind: from 040° at 13 knots
- Visibility: 10 statute miles
- Sky: clear
- Temperature: 68°F (20°C), dew point 41°F (5°C)
- Altimeter: 29.99 inHg
- Observation at 5:35 pm from KCHK, 7 miles away
Weather report (METAR): METAR KCHK 302235Z AUTO 04013KT 10SM CLR 20/05 A2999 RMK AO2
Injuries
| Fatal | Serious | Minor | None | |
|---|---|---|---|---|
| Flight crew | 1 |
Documents from the investigation the NTSB's docket: the evidence folder behind the report
The NTSB has not released the docket for this case yet. The docket, the folder of records gathered during an investigation (maintenance records, photographs, witness statements, examinations), is usually released when the investigation is nearly complete, and the list here is refreshed when it appears. Check at the NTSB.
About this page
Everything above comes from the NTSB's public accident database: the narrative, probable cause and findings are the NTSB's own words, and the coded tables behind its report (pilot, aircraft, flight, weather, injuries, sequence of events) are written out in plain English. Pilots' ages, home towns and medical details are left out on purpose. The documents and photographs are the NTSB's docket, the folder of records gathered during the investigation, shown as the NTSB released them (the NTSB redacts some personal details first) and listed under the NTSB's own titles. This site's own text never names pilots, passengers or anyone else involved. A preliminary report describes what is known soon after the event and can change; the final report, with the probable cause, usually follows one to two years later and this page is refreshed when it does. Case number CEN26LA175.