Preliminary Report: Medical Helicopter Went Inverted Before Crashing In PA

National Transportation Safety Board
Aviation Accident Preliminary Report
Location: Drexel Hill, PA Accident Number: ERA22FA105
Date & Time: January 11, 2022, 12:55 Local Registration: N531LN
Aircraft: EUROCOPTER DEUTSCHLAND
GMBH EC 135 P2+ Injuries: 1 Minor, 3 None
Flight Conducted
Under: Part 135: Air taxi & commuter – Non-scheduled – Air Medical (Medical emergency)

On January 11, 2022, about 1255 eastern standard time, a Eurocopter EC-135 P2+, N531LN, was
substantially damaged when it was involved in an accident in Drexel Hill, Pennsylvania. The airline
transport pilot was seriously injured. The two medical crew members and the patient were not injured.
The helicopter was operated by Air Methods Corporation as a Title 14 Code of Federal Regulations
Part 135 air ambulance flight.

Preliminary Automatic Dependent Surveillance – Broadcast (ADS-B) data revealed that the helicopter
departed Chambersburg Hospital Heliport (PA60) about 1205 and was destined for Children’s Hospital
of Philadelphia Heliport (9PN2), Philadelphia, Pennsylvania. The track showed the helicopter in a cruise
profile on an easterly track about 3,500 ft mean sea level (msl). About 1243, the helicopter descended
and then leveled about 2,800 ft msl, then subsequently descended and leveled at 1,500 ft msl, tracking
directly toward 9PN2. At 1253:11, the helicopter track depicted a series of heading and altitude
excursions. The plots depicted altitudes between 1,700 ft msl and 1,250 ft msl before the target
disappeared at 12:53:17.

In a written statement, a witness whose home was directly beneath the helicopter’s flight path said that
he was an aviation enthusiast and was familiar with the many helicopters flying to and from area
hospitals. He said that his attention was drawn to the accident helicopter because it was “very low and
louder than normal” and that the “tone” of the rotors was unfamiliar. According to the witness, the
helicopter was “in a nose down attitude… far less than 1,000 ft above the ground… [and] rotating
around its longitudinal axis.”

A doorbell camera about 1 mile from the accident site, and approximately beneath the helicopter’s flight
path, captured both audio and video of the helicopter’s initial descent from its cruise altitude. The sound
could be heard before the helicopter entered the frame. The helicopter’s departure from controlled flight
was not captured, as it was blocked by a porch awning on the front of the house. A high-pitched whine
was heard, increasing in volume and pitch before the helicopter appeared beneath the awning above the
camera in a near vertical, nose-down descent. The helicopter’s angle of descent shallowed as it
disappeared behind a tree line. The volume and pitch of the sound continued to increase for a time after
the helicopter disappeared and before the sound ultimately faded.

A second witness nearby said that he saw a helicopter “very low…very loud…banked right and left out
of control, then appeared to straighten…” before it disappeared from view.

Brief video clips from open-source media outlets showed the helicopter upright, in a steep descent,
exhibiting small but rapid changes in each axis (pitch, roll, yaw). A home doorbell camera captured the
last second of flight as the helicopter appeared level in the frame, in a slight nose-up attitude, as it
impacted the ground, separating the tailboom, then disappeared from view.

The pilot made himself available for interview, but the interview was postponed due to his medical
condition.

The flight nurse and flight medic were interviewed by a Federal Aviation Administration (FAA) aviation
safety inspector. According to the flight medic, the flight was routine, and they were within 10 minutes
of landing at 9PN2. He and the flight nurse were out of their seats treating the patient when a loud
“bang” was heard, and the helicopter banked sharply right and continued into a right roll. The medic
said that the helicopter rolled inverted, perhaps multiple times, and that he and the nurse were “pinned to
the ceiling” and internal communication was lost. The helicopter was leveled, the patient was secured,
the crewmembers secured themselves in their seats, and they braced for landing.

Following the accident, the flight nurse evacuated the patient, then evacuated the pilot while the medic
shut down both engines. The nurse traveled with the patient while the medic traveled with the pilot to
area hospitals.

The pilot held an airline transport pilot certificate with ratings for airplane multiengine land and
rotorcraft-helicopter, with private pilot privileges for airplane single-engine. The pilot’s most recent
second-class FAA medical certificate was issued on August 26, 2021.

The operator reported that the pilot had accrued 4,123 total hours of flight experience of which 3,400
hours were in helicopters and 185 hours were in the accident helicopter make and model.

The helicopter was examined at the accident site and all major components were accounted for at the
scene. The was a strong odor of fuel and evidence of fuel spillage. The wreckage path was oriented
about 150° magnetic and measured about 108 ft long. The initial impact point was in a tree about 40 ft
tall, and pieces of freshly broken and cut wood were found beneath it.

The helicopter came to rest on its left side, nearly inverted, against a stone wall. The tailboom was
separated at the fuselage and rested between the helicopter and the wall. The fenestron was intact inside
its shroud. Fenestron drive and control continuity was confirmed through several breaks which appeared
due to overload. The fenestron flexball cable was found wrapped around the main rotor mast. The
landing gear was destroyed by impact and the windscreen and chin bubble on the copilot’s (left) side
were destroyed; the airframe and cockpit and cabin floors displayed impact fractures, but the cockpit,
instrument panel, and cabin area remained largely intact. The cockpit controls were connected and

intact. While the yaw control pedals remained attached to their respective control tubes, the floor
structure that contained each pedal assembly mount was fractured. The engines and main transmission
were secure in their mounts, the main rotor hub was attached to the mast, and the root ends of all four
main rotor blades were secure in the hub. Two main rotor blades were wrapped around the mast, one
was straight with a chordwise fracture, and the fourth was separated from the hub during recovery.

Later, all four blades were cut near their root to facilitate further examination. The wreckage was recovered to an aircraft recovery facility in Clayton, Delaware, for further examination.

The engines and main transmission were secure in their mounts. Continuity was confirmed from the
main rotor head, through the transmission, to the #1 and #2 high speed shafts. The functionality of the
freewheeling unit was confirmed.

Cyclic and collective control continuity were confirmed from the controls to the main rotor system. The
blue pitch-change link was fractured due to overload, and the yellow link was impact damaged.
Data downloaded from each engine revealed nominal engine performance consistent with the mission
profile across the duration of the flight.

Components from the cockpit warning system, electrical and hydraulic components from the autopilot
and flight control system, as well as fluid samples, were retained for further examination.

Aircraft and Owner/Operator Information
Aircraft Make: EUROCOPTER
DEUTSCHLAND GMBH
Registration: N531LN
Model/Series: EC 135 P2+ Aircraft Category: Helicopter
Amateur Built:
Operator: Operating Certificate(s)
Held:
On-demand air taxi (135)
Operator Designator Code:
Meteorological Information and Flight Plan
Conditions at Accident Site: VMC Condition of Light: Day
Observation Facility, Elevation: PHL,10 ft msl Observation Time: 12:54 Local
Distance from Accident Site: 6 Nautical Miles Temperature/Dew Point: -4°C /-19°C
Lowest Cloud Condition: Few / 6000 ft AGL Wind Speed/Gusts, Direction: 8 knots / 17 knots, 310°
Lowest Ceiling: Visibility: 10 miles
Altimeter Setting: 30.53 inches Hg Type of Flight Plan Filed: VFR
Departure Point: Chambersburg, PA (PA60) Destination: Philadelphia, PA (9PN2)
Wreckage and Impact Information
Crew Injuries: 1 Minor, 2 None Aircraft Damage: Substantial
Passenger Injuries: 1 None Aircraft Fire: On-ground
Ground Injuries: Aircraft Explosion: None
Total Injuries: 1 Minor, 3 None Latitude,
Longitude:
39.947563,-75.30347 (est)
Administrative Information
Investigator In Charge (IIC): Rayner, Brian
Additional Participating Persons: Michael Bauer; FAA/FSDO; Philadelphia, PA
Seth Buttner; Airbus Helicopters; Grand Prairie, TX
Kevin Drew; Air Methods; Greenwood Village, CO
Axel Rokohl; German Federal Bureau of Aircraft Accident Investigation; Braunschweig
Note:

Source: FAA