CEN21LA222 · Flight Design Gmbh CTLS
Flight Design Gmbh CTLS · Accident: powerplant system/component malfunction/failure on approach
From Burlington Municipal Airport (BUU) to an unrecorded destination
Event
- NTSB case
- CEN21LA222
- 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
- Event fatalities
- Unknown
- 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
Flight Design Gmbh CTLS
- Aircraft type
- Flight Design CTLS
- 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
- N521CT
- Operator
- Racine Sport Flyers
- Onboard fatalities
- Unknown
- Route
- From Burlington Municipal Airport (BUU), Burlington, WITo not recorded
- Aircraft age
- About 13 years (built 2008)
- 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
- Approach
- 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
- Powerplant system/component 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
- Destroyed
Cause areas
- Aircraft › Aircraft power plant
Approximate · Coordinates from the NTSB case API, which marks them as estimated or does not say; no uncertainty radius is established.
NTSB narrative
During a solo cross-country flight, the student pilot returned to the departure airport after the engine began to vibrate when power was reduced. She attempted three landings that were aborted due to excessive airspeed. During the fourth landing attempt, the airplane touched down fast and bounced several times on the runway. The student pilot aborted the landing and added full engine power to climb, but the airspeed decreased. The airplane collided with a tree and a building and was destroyed by impact forces. Postaccident examination of the airplane revealed that one of the two throttle control cables had separated from its carburetor at the control arm. The cable separation from the carburetor resulted in the carburetor’s spring-loaded throttle control moving to full throttle while the second carburetor would have been at a position selected by the cockpit throttle control. When the pilot reduced the cockpit throttle control for landing, the carburetor with the broken cable would have continued operating at maximum throttle regardless of the cockpit throttle control position, which likely resulted in the engine vibration and the excessive airspeed for landing. Metallurgical examination of the separated control cable revealed that a tightly focused clamping force on the carburetor cable attachment bolt resulted in fatigue failure of the cable.
Probable cause
The fatigue failure of the carburetor throttle control cable, which resulted in a partial loss of engine control.
Verbatim NTSB analysis and probable cause from the NTSB dataset
Sources
NTSB record CEN21LA222
- Event ID
- 20210518103095
- Case number
- CEN21LA222
- 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: local date, investigation status, coordinates, cause areas. Values present in the bulk record are kept.
- The date is the local date; the NTSB stores the UTC date 2021-05-18.
- API snapshot SHA-256: 9120128e079492ba26cfd01956c39afc6ac3c8d41694ddbc672dcb7510754efa; retrieved 2026-09-16T14:03:19.618Z.