CEN12CA474 · Eurocopter Deutschland Gmbh MBB-BK 117 C-2
Memorial Hermann Hospital System Eurocopter Deutschland Gmbh MBB-BK 117 C-2 · Accident during landing
From Katy, TX (no airport) to John S Dunn Heliport (38TE)
Event
- NTSB case
- CEN12CA474
- 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
Eurocopter Deutschland Gmbh MBB-BK 117 C-2
- Aircraft type
- Eurocopter MBB-BK 117 C-2
- Category
- Helicopter
- 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
- N455MH
- Operator
- Memorial Hermann Hospital System
- Onboard fatalities
- Unknown
- Route
- From Katy, TX (no airport)To John S Dunn Heliport (38TE), Houston, TX
- 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
- 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
- Miscellaneous/other
- 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 power plant
- Personnel issues › Task performance
Approximate · Coordinates as recorded by the NTSB; no uncertainty radius is established.
NTSB narrative
The emergency medical services helicopter was about 800 feet above ground level and landing at a rooftop hospital helipad in a congested metropolitan area when the left side engine cowling opened. The cowling partially separated and impacted the bottom of all four main rotor blades, resulting in substantial damage to the rotor blades. The pilot described the event as a brief shudder, like flying through the rotor wash of another helicopter. The pilot was unaware that any damage had occurred and landed uneventfully. A third medical crewmember boarded through the right rear door for a local flight to a suburban hospital. During engine shutdown at their destination, another medical crewmember exited the helicopter on the left side and was the first to notice the damage. The pilot stated that he failed to complete a thorough preflight inspection before the accident flight, because the crew was assigned a medical mission just after their shift started. The previous pilot, who flew the helicopter the evening before the accident, stated that he had opened the left side engine cowling to check the oil level and became distracted. He also stated that he could not remember if he had secured the cowling latches.
Probable cause
The pilot’s inadequate preflight inspection, which failed to detect the unsecured cowling latches and resulted in the in-flight opening of an engine cowling.
Verbatim NTSB analysis and probable cause from the NTSB dataset
Sources
NTSB record CEN12CA474
- Event ID
- 20120724X52626
- Case number
- CEN12CA474
- 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: 427fb1eb121a3d4e1a838c19c5d0a5cdb444ad1b19a9497c0c204f7124d2bdcc; retrieved 2026-09-15T19:04:06.348Z.