WPR12FA421 · Frederick F 1
Frederick F 1 · Accident: flight control system malfunction/failure while maneuvering
From Reno-Stead Airport (RTS) to Reno-Stead Airport (RTS)
Narrative check · The NTSB narrative appears to contradict this record's location. Values are shown as recorded, not corrected; compare with the narrative.
Event
- NTSB case
- WPR12FA421
- Event typeAccident: someone killed or seriously injured, or the aircraft substantially damaged (NTSB definition). Incident: an occurrence that affected or could have affected safety, short of that. Glossary
- Accident
- InvestigationHow far the investigation had got when the record was published: preliminary, ongoing, final or completed. Unknown where the source does not say. Glossary
- Completed
- API-reported fatalities
- 0 · all aircraft and ground
- Ground fatalities
- Unknown
- OperationWhat kind of flying it was, grouped by the rules it flew under: airline (US Part 121), air taxi and commuter (Part 135), general aviation (Part 91 and similar), military or government. Glossary
- General aviation
- WeatherVisual meteorological conditions (VMC): good enough to fly by looking outside. Instrument conditions (IMC): cloud or low visibility, flying by instruments. Glossary
- Visual Meteorological Cond
Frederick F 1
- Aircraft type
- Frederick F-1
- Category
- Airplane
- RegistrationThe aircraft's tail number, such as N12345 or G-ABCD. Registrations are reissued, so the same one years apart can be a different aircraft. Glossary
- N158CF
- Operator
- Unknown
- Onboard fatalities
- Unknown
- Route
- From Reno-Stead Airport (RTS), Reno, NVTo Reno-Stead Airport (RTS), Reno, NV
- Aircraft age
- Not recorded
- Flight rulesThe regulations the flight operated under: in the US, Part 91 (general aviation), Part 121 (airlines), Part 135 (air taxi and commuter) and others; for flights abroad, the NTSB's coarser commercial or non-commercial code. Glossary
- Part 91: General Aviation
- Phase of flightThe stage of the flight when things started to go wrong: standing, taxi, takeoff, initial climb, en route, maneuvering, approach or landing. Glossary
- Maneuvering · low-altitude flying
- Defining eventThe single coded event the NTSB judges best describes what happened (records from 2008 on). Older records name the first occurrence in the sequence instead. Glossary
- Flight control system malfunction/failure
- DamageDestroyed: beyond practical repair. Substantial: damage that affects the structure, performance or handling and normally needs major repair. Minor: less than that. Glossary
- Substantial
Cause areas
- Aircraft › Aircraft oper/perf/capability
- Aircraft › Aircraft structures
- Personnel issues › Task performance
Approximate · Coordinates as recorded by the NTSB; no uncertainty radius is established.
NTSB narrative
The accident airplane was participating in an air race, and, when the airplane was at 180 knots indicated airspeed (KIAS), the pace airplane released the flight of airplanes to enter the race course. The pilot reported that, shortly after, a "vibration" began at an unknown airspeed and that it then increased to a heavy flutter event. The pilot pitched the airplane upward and reduced the airspeed. As the airspeed decreased below 90 KIAS, the vibration stopped, and the pilot landed uneventfully.
Postaccident examination of the control horn assembly revealed fractures at the forward and aft trim tab control horn brackets and the rod end clevis. According to the airplane manufacturer's assembly manual, the aft trim tab control horn was supposed to be attached to the lower skin with four rivets. However, examination revealed that only three of the four rivets were installed; no evidence of a through hole for the fourth rivet was found. The lack of the fourth rivet allowed the aft bracket to flex, and the relative movement between the bracket and the trim tab skin during flight resulted in fretting damage. Examination of the aft bracket's fracture surface revealed features consistent with an overstress separation.
The published never-exceed speed for the airplane was 240 knots true airspeed (KTAS). The airspeed was calculated to be 266 KTAS at the time of the event. The airplane's excessive speed coupled with the incorrect installation of the trim tab control horn likely initiated the flutter in the left elevator trim tab during the start of the air race. The flutter subsequently produced dynamic loads in the trim tab control system that exceeded the material strength of the system components and led to the fracture of the forward and aft trim tab control horn brackets and the rod end clevis before the airplane was slowed sufficiently to stop the flutter.
Probable cause
The pilot’s operation of the airplane above the established never-exceed speed and the incorrect installation of the trim tab control horn, which resulted in the flutter of the left elevator trim tab.
Verbatim NTSB analysis and probable cause from the NTSB dataset
Sources
NTSB record WPR12FA421
- Event ID
- 20120915X23852
- Case number
- WPR12FA421
- Dataset
- full-current
- Source SHA-256
- 5cf380f0061817c0331a6b2d8cc7e0ee3a79bea469a1001dc5c10e56f35f5ab3
Source notes (4)
- Unreviewed is an editorial label, not an investigation status. API-sourced is not report-checked or human-reviewed. Explicit event totals are used without summing aircraft injury tables; onboard allocation is withheld. Unknown values remain unknown. The operation category is mapped from the NTSB-reported FAR part and has not been reviewed.
- Filled from the NTSB case API where the bulk record had no value: investigation status. Values present in the bulk record are kept.
- The date is the local date, which is the same as the UTC date the NTSB stores.
- API snapshot SHA-256: 4320ce9d4a407cd932f6c05cf87afd605ae571bc6beee128e3af39998d1475fe; retrieved 2026-09-15T19:52:37.043Z.