SEA02LA014

NTSB accident investigation · Bölkow BO 105 LS · Mud Lake, ID · November 14, 2001

Accident · Serious injuriesLimited investigationFinal report
Date
November 14, 2001, 00:33 local (07:33 UTC)
Place
Mud Lake, ID
Injuries
1 serious
Damage
Destroyed
Phase of flight
Enroute
Aircraft
N93LFBölkow BO 105 LS
Weather
Night/dark
Status
Completed · report June 3, 2002
Report
Approved by Office Director
Parties
FAA-FSDO
FAA report
20011114032029A
Case key
53796

From the NTSB’s public API. By law, NTSB reports can’t be used as evidence in lawsuits over the accident.

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Probable cause

The NTSB’s determination of the probable cause, and any contributing factors.

Pilot's failure to maintain adequate separation from terrain during the initial climb. Factors include spatial disorientation and a dark moonless night.

Analysis

In a written statement, the pilot reported that during a medical transport flight he performed a precautionary off airport landing due to a problem with the helicopter's fuel transfer pumps. After the repairs were made to the helicopter, the pilot initiated a normal departure under dark night conditions. Shortly after departure the helicopter collided with terrain. The pilot later reported that during the initial climb out, he lost visual references outside the aircraft and became disoriented just before the helicopter collided with terrain. The pilot reported no mechanical malfunction or failure had occurred during the accident flight.

Factual narrative

The factual narrative517 words

On November 14, 2001, at 0033 mountain standard time, a Messerschmitt-Bolkow-Blohm, BO 105 LS helicopter, was destroyed when it collided with terrain in a rural area near Mud Lake, Idaho. The helicopter is owned by Bannock Medical Center, Pocatello, Idaho, and was being operated as a visual flight rules (VFR) repositioning flight under the provisions of Title 14 CFR Part 91. No flight plan was filed. The commercial pilot-in-command, the sole occupant, sustained serious injuries. The flight originated from an area near Mud Lake, with a planned destination of Pocatello, Idaho.

In a written statement, the pilot reported that during a medical transport flight, with a patient and medical crew aboard, he performed a precautionary off airport landing (approximately 30-40 minutes after departure) due to a problem with the helicopter's fuel transfer pumps. Upon landing, the patient and medical crew were offloaded and transported to the destination hospital via ground ambulance. Approximately five hours after the unscheduled landing, a mechanic employed by the operator arrived to make appropriate repairs to the helicopter. The pilot reported that while the mechanic worked on the aircraft, he slept in the mechanic's vehicle for approximately 1.5 hours. After the repairs were made to the helicopter, the pilot conducted a post-maintenance ground run that lasted approximately 10 minutes. At the conclusion of the ground run, the pilot initiated a normal departure, under dark night conditions, with an intended destination of Pocatello. The pilot reported to the FAA Principal Operations Inspector that shortly after departure he recalled seeing the silhouette of mountains, and the stars were visible, but fuzzy looking. In a written statement, the pilot reported, "I decided to take off and head back towards Bannock. I was trying to stay with the road but shortly after takeoff, I lost visual sight of the road. I could no longer make out the ridgeline. I tried to cross-scan between inside and outside the aircraft and all of a sudden I was disoriented. I couldn't tell which way was up or down. Then came impact". The pilot further stated that he came to rest upside down, released his seat belt and pulled himself away from the helicopter wreckage.

The mechanic reported that he had driven to the helicopter to repair the fuel system problem. He stated to the FAA Principal Operations Inspector that he replaced the number one and number two fuel transfer pumps, filled the main tanks with 20 gallons of fuel, and checked the operation of the pumps. He stated that the pilot warmed up the aircraft for approximately 10 minutes, and then he observed the helicopter take off. He stated "I started forward on the highway when off to the left I saw a very bright glow reflected in the air above the foothills that got quite intense". The mechanic reported that he then drove towards the glow, found the wreckage and the pilot, put out a small fire, disconnected the aircraft's battery, and called for help.

The pilot reported to the FAA Principal Operations Inspector that he noted no mechanical failures or malfunctions with the helicopter during the accident flight.

Sequence of events

NTSB’s coding before 2008: each occurrence and phase of flight, and the causes and factors under it. The codes are defined in NTSB’s coding manual.

In flight collision with terrain/waterClimb
Light condition - dark nightFactor
Altitude/clearance - not obtained/maintainedPilot in commandCause
Spatial disorientationPilot in commandFactor

Aircraft

Registration
N93LF
Reported as
Bölkow BO 105 LS
Category
Helicopter
Serial number
2038
Airframe hours
3,811.3
Engines
Allison 250-C28C, 500 horsepower, turbo shaftAllison 250-C28C, 500 horsepower, turbo shaft
Damage
Destroyed
Fire
On-Ground
Flight
Positioning · Part 91
Registered owner
Bannock Regional Medical Cen
Airworthiness certificate
Standard, Normal
Last inspection
100 hour · November 5, 2001 · 10 hours before
Departed
Mud Lake, ID
Destination
PIH · Pocatello, ID

Matched to the registry by N-number and the event date; the registry’s history has gaps, so older matches can be wrong. Compare the reported make and model.

Flight crew

As NTSB recorded them. NTSB leaves out names.

Role
Pilot
Age
45
Injuries
Serious
Certificate
Commercial
Instrument ratings
Helicopter
Medical
Class 2, Valid Medical--no waivers/lim.
Last flight review
October 11, 2001
Seat
Right
Flight hours
5,300 total · 230 in this make and model · 4,100 as pilot in command · 20 in the last 90 days · 6 in the last 30 days · 2 in the last 24 hours

Weather

Conditions
Night/dark
Temperature
19 °F

FAA reports on this event · 1

The FAA’s own accident and incident reports, matched to the aircraft by N-number and date.