What happened
A medical evacuation helicopter was destroyed by fire while stationary at a hospital heliport. The aircraft had recently completed a patient transport mission, during which the onboard oxygen supply was depleted to low levels. Following the landing, two respiratory therapists initiated the process of refilling the oxygen system.
The servicing procedure required access to a rear baggage compartment located on the exterior of the fuselage. According to witness accounts, the fire broke out near the connection point almost immediately after the fill line was attached and the valve was partially opened. The blaze consumed the aircraft rapidly.
In the aftermath, one of the therapists recalled noticing an oil spill above the baggage door area prior to starting the refill. This oil had not been cleaned up before the operation began. Subsequent testing of the valve revealed significant leakage at the connection point. A wrench was required to separate the components for inspection. The physical examination showed no debris or distortion of the threaded connection, suggesting the leak was mechanical rather than caused by damage during the incident.
The investigation
Investigators examined the oxygen servicing system and the condition of the baggage compartment access area. Key findings included:
- Significant valve leakage at the connection point after the fire
- Uncleaned oil residue present above the baggage door prior to servicing
- No mechanical damage or debris found in the threaded portion of the connection during inspection
- No flight crew was present during the operation, and there was no intent for immediate flight