ANC06LA073

NTSB accident investigation · MBB BK 117A-3 · Ponce de Leon, FL · June 22, 2006

Accident · Minor injuriesLimited investigationFinal report
Date
June 22, 2006, 01:30 local (06:30 UTC)
Place
Ponce de Leon, FL
Injuries
1 minor, 2 uninjured
Damage
Substantial damage
Phase of flight
Maneuvering
Aircraft
N913EFMBB BK 117A-3
Weather
Visual (VMC) · Night
Status
Completed · report April 25, 2007
Report
Approved by Office Director
NTSB office
Alaska Regional Office
Parties
Federal Aviation Administration
FAA report
20060622014289A
Case key
63960

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 pilot's failure to maintain clearance from objects while hovering in ground effect, which resulted in an in-flight collision with a tree. Factors associated with the accident were loose, sand-covered terrain, and the operator's failure to ensure that the pilot was provided with current, off-airport landing site condition information.

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 objectHover - in ground effect
Clearance - not maintainedPilot in commandCause
Unsafe/hazardous condition - not identifiedCompany/operator managementFactor
Terrain condition - loose gravel/sandyFactor
Object - tree(s)
Light condition - night
Loss of control - in flightHover - in ground effect
In flight collision with terrain/waterDescent - uncontrolled
Terrain condition - ground

Analysis

The commercial certificated pilot was transporting two medical crewmembers under Title 14, CFR Part 91, to a prearranged landing site to meet ambulance and fire department personnel caring for a patient. The flight was conducted during dark night conditions. The accident helicopter had predetermined landing site locations stored in its onboard GPS navigation system. The stored landing sites had been previously inspected for obstruction clearance and overall suitability. After arriving overhead of what he thought was a sod-covered field, the pilot used an externally mounted searchlight to aid in seeing the ground and obstructions during the landing approach. As the helicopter approached the open field and transitioned from forward flight to a hover, the pilot encountered blowing, dry sand and dust created by the helicopter's main rotor downwash, which reduced his visibility. He stated he lost all visual reference with the surface of the field, and while attempting to regain a visual reference, the helicopter's main rotor struck a large tree, and the fuselage began to rotate. The helicopter's tail boom assembly subsequently struck the tree, and the helicopter impacted terrain. The helicopter sustained substantial damage to the main rotor drive system, tail boom assembly, and fuselage. A postaccident inspection of the landing site disclosed that the sod had recently been removed from the field, leaving a dry, sand-covered field. The pilot reported that there were no preaccident mechanical anomalies with the helicopter.

Factual narrative

On June 22, 2006, about 0130 central daylight time, a skid-equipped Messerschmitt-Bolkow-Blohm (MBB) BK 117A-3 helicopter, N913EF, sustained substantial damage after colliding with trees while landing at an off-airport site, about 10 miles north of Ponce de Leon, Florida. The helicopter was being operated as a visual flight rules (VFR) emergency medical services (EMS) positioning flight under Title 14, CFR Part 91, when the accident occurred. Of the three occupants aboard, the certificated commercial helicopter pilot and one medical crewmember were not injured. The remaining medical crewmember sustained minor injuries. The helicopter was operated by CJ Systems Aviation Group, of West Mifflin, Pennsylvania. The medical facility, Doctor's Memorial Hospital, based in Bonifay, Florida, was utilizing CJ Systems Aviation Group to provide EMS helicopter transport services. The helicopter was en route to a prearranged landing site to meet ambulance and fire department personnel caring for a patient. Dark night, visual meteorological conditions prevailed, and company flight following procedures were in effect. The flight originated about 0110, from the Tri-County Airport, Bonifay.

During a telephone conversation with the National Transportation Safety Board (NTSB) investigator-in-charge (IIC), on June 22, the pilot reported that he was transporting two flight paramedics to a rural community located in Holmes County to pickup a maternity patient. He said that pilots use a number of prearranged landing sites in the area, which have been previously inspected for obstruction clearance, as well as the overall site condition. According to the pilot, these prearranged landing site locations are stored in the helicopter's onboard GPS navigation system.

The pilot said that during the outbound flight, fire department personnel contacted him via radio and requested that the landing site be changed to another prearranged landing site, a sod-covered open field. He agreed to the change, selected the new landing site from coordinates previously stored in the GPS, and went to the new site. He reported that after arriving overhead of what he thought was a sod-covered field, he used an externally mounted searchlight to aid in seeing the ground and obstructions during the landing approach. As the helicopter approached the open field, and transitioned from forward flight to a hover, the pilot said he encountered a substantial amount of blowing, dry sand and dust created by the helicopter's main rotor downwash, which momentarily reduced his visibility. He stated he lost all visual reference with the surface of the field, and while attempting to regain a visual reference, the helicopter's main rotor struck a large tree, and began to spin. The helicopter's tail boom assembly subsequently struck the tree, and the helicopter impacted terrain. The helicopter sustained substantial damage to the main rotor drive system, tail boom assembly, and fuselage. The pilot reported that there were no preaccident mechanical anomalies with the helicopter.

A postaccident inspection of the landing site disclosed that the sod had recently been removed from the field, leaving a dry, sand-covered field.

Aircraft

Registration
N913EF
Reported as
MBB BK 117A-3
Category
Helicopter
Serial number
7032
Airframe hours
8,882.3
Engine
Lycoming LTS101-650-B1, 600 horsepower, turbo shaft
Damage
Substantial damage
Flight
Positioning · Part 91
Operator
Corporate Jets Inc, doing business as CJ Systems Aviation Group
Registered owner
PNC Bank and Trust
Airworthiness certificate
Standard, Normal
Last inspection
AAIP · June 1, 2006 · 8.8 hours before
Departed
02FD · Bonifay, FL
Destination
Prosperity, FL
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
48
Injuries
None
Certificate
Commercial
Instrument ratings
Helicopter
Medical
Class 2, With waivers/limitations
Last flight review
April 1, 2006
Seat
Right
Flight hours
4,726 total · 66 in this make and model · 3,500 as pilot in command · 48 in the last 90 days · 9 in the last 30 days · 1 in the last 24 hours

Weather

Conditions
Visual (VMC) · Night
Wind
230° at 3 knots
Visibility
6 statute miles
Lowest ceiling
None
Temperature
77 °F, dew point 68 °F
Altimeter
30.12 inHg

FAA reports on this event · 1

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