- Date
- October 26, 1991, 15:15 local (22:15 UTC)
- Place
- Scottsdale, AZ
- Injuries
- 2 minor, 1 uninjured
- Damage
- Substantial damage
- Phase of flight
- Maneuvering
- Aircraft
- N9001SAerospatiale AS350B
- Weather
- Visual (VMC) · Day
- Status
- Completed · report May 3, 1993
- Report
- Approved by Office Director
- FAA report
- 19911026048079A
- Case key
- 27388
From the NTSB’s public API. By law, NTSB reports can’t be used as evidence in lawsuits over the accident.
On this page
Probable cause
An undetermined malfunction of the hydraulic system in which the system was locked, preventing the movement of the flight controls, and loss of directional control.
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.
Analysis
The certificated commercial pilot/certified flight instructor was conducting training with a second pilot in helicopter emergency procedures, that included hyraulics off landings. On the third landing without hyraulic boost pressure, at an airspeed of about 2 knots and a skid height of about 1 foot, the helicopter began an uncommanded turn to the left. The pilot attempted to counter the turn but was unable to move the flight controls. The helicopter's left bank angle, nose down attitude and left turn continued until the main rotor blades struck the ground. The left front portion of the fuselage and skid tube then struck the ground. An examination of the hydraulic system, including disassembly of the main rotor control servos, failed to locate the cause of the malfunction. This is the second rptd hyd off flt control seizure that resulted in an accident. The flt crew of both helicopters were well qualified.
Aircraft
- Registration
- N9001S
- Reported as
- Aerospatiale AS350B
- Category
- Helicopter
- Serial number
- 1022
- Airframe hours
- 6,641
- Engine
- Turbomeca ARRIEL 1B, 641 horsepower, turbo shaft
- Damage
- Substantial damage
- Flight
- Instructional · Part 91
- Operator
- Lone Eagle Aviation, Inc., doing business as Eagle Rescue Of Arizona
- Registered owner
- Mark A. Berlin Trustee
- Airworthiness certificate
- Standard, Normal
- Last inspection
- Annual · October 21, 1991 · 23 hours before
- Departed
- SDL · Scottsdale, AZ
- Flight plan
- Company VFR
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
- 37
- Certificates
- Commercial, Flight instructor
- Airplane ratings
- Multi-engine land, Single-engine land
- Instrument ratings
- Helicopter, Airplane
- Medical
- Class 1, Valid Medical--no waivers/lim.
- Seat
- Left
- Flight hours
- 8,248 total · 312 in this make and model · 8,185 as pilot in command
Weather
- Conditions
- Visual (VMC) · Day
- Wind
- 180° at 7 knots
- Visibility
- 40 statute miles
- Lowest ceiling
- None
- Temperature
- 77 °F, dew point 37 °F
- Altimeter
- 29.00 inHg
- Observed at
- SDL, 5 nm away
FAA reports on this event · 1
The FAA’s own accident and incident reports, matched to the aircraft by N-number and date.