CEN17IA155 · Cessna 172RG
Cessna 172RG · Incident: landing gear collapse
From Northeast Wyoming Regional Airport (GCC) to Colorado Plains Regional Airport (AKO)
Event
- NTSB case
- CEN17IA155
- 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
- Incident
- 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
Cessna 172RG
- Aircraft type
- Cessna 172
- 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
- N6402V
- Operator
- Unknown
- Onboard fatalities
- Unknown
- Route
- From Northeast Wyoming Regional Airport (GCC), Gillette, WYTo Colorado Plains Regional Airport (AKO), Akron, CO
- Aircraft age
- About 37 years (built 1980)
- 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
- Landing
- 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
- Landing gear collapse
- DamageDestroyed: beyond practical repair. Substantial: damage that affects the structure, performance or handling and normally needs major repair. Minor: less than that. Glossary
- Minor
Cause areas
- Aircraft › Aircraft systems
Approximate · Coordinates from the NTSB case API, which marks them as estimated or does not say; no uncertainty radius is established.
NTSB narrative
At the end of a cross-country flight, the commercial pilot noted that the left main landing gear would not extend. He elected to divert to another airport and land with the gear retracted. Postaccident examination revealed that the left main landing gear actuator assembly housing was cracked across the forward attach bolt hole, which resulted in the inability to fully raise or extend the landing gear using either the normal method or the emergency hand pump.
Following the incident, the Federal Aviation Administration released a Special Airworthiness Information Bulletin (SAIB) emphasizing the importance of inspecting main landing gear actuator assemblies. This SAIB recommended complying with a supplemental inspection document provided by the manufacturer that prescribed a combination of visual, fluorescent penetrant, and eddy current inspections. The SAIB also included initial and repetitive inspection intervals.
Probable cause
Failure of the left main landing gear actuator assembly, which resulted in an inability to extend the left main landing gear.
Verbatim NTSB analysis and probable cause from the NTSB dataset
Sources
NTSB record CEN17IA155
- Event ID
- 20170417X01326
- Case number
- CEN17IA155
- 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, coordinates. 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: 44da4eb8ef1f0d13cb5f28eb207fd8eb0622bee3a0448e320cfa008e1c0c9f67; retrieved 2026-09-16T05:10:21.508Z.