Tucson International Airport
Aircraft Accident/Incident Report

Tucson, Arizona 85706
Tuesady, June 15, 1999 13:35 MST

NTSB Narrative Summary Released at Completion of Accident

The pilot was on short final approach to land when he reported an engine failure. He attempted to stretch his glide to avoid buildings and cars on the ground; however, the helicopter struck railroad tracks next to the field boundary. Damage to the main rotor blades was consistent with a low rotor rpm at impact. The pilot did not recall how much time had elapsed since his last refueling. Examination of the navigation and fuel endurance log from the helicopter cockpit (required by the operator) showed the pilot had not completed the fuel endurance calculations at the time of last fueling. The helicopter was equipped with a main fuel system and an auxiliary fuel system. A deferred maintenance item, 'main fuel gauge unreliable in forward flight,' was still open. The same discrepancy had also been entered previously and it, too, had not been cleared. The auxiliary fuel gauge was entered as inoperative on the deferred maintenance log with 'parts on order' but had not been cleared at the time of the accident. The pilot last recalled reading approximately 78 pounds on the main fuel gauge. He did not recall seeing the 20-minute light illuminate before the accident. A check of the low fuel warning system found that float arm contact in the fuel cell occurred at 34 pounds, which approximates 20 minutes of usable fuel; no discrepancies were found in the operation of the system. No evidence of a fuel spill was found around or under the wreckage. The crashworthy main fuel cell was uncompromised and about 12 ounces of trapped fuel was found. No fuel was found in the auxiliary fuel tank. The light bulbs for the 'Engine Out, Fuel Low, and Master Caution' were removed for examination. One 'Master Caution' bulb showed a small amount of filament stretching, consistent with hot stretching from a light to moderate impact force. The filaments of both 'Fuel Low' bulbs were intact and unstretched, consistent with bulbs not being illuminated during a light to moderate impact. The filaments from both 'Engine Out' bulbs showed a small amount of stretching, again consistent with hot stretching from light to moderate impact. There were no other discrepancies found with the engine or engine-related systems.

NTSB Probable Cause Narrative

Fuel exhaustion resulting from pilot's failure to perform adequate fuel consumption calculations. The unreliable and inoperative fuel level indicating system components and the operator's operation of the aircraft with known deficiencies were factors in the accident.

Event Information

Type of Event Accident
Event Date 6/15/1999
Event Day of the Week Tuesday
Time of Event 1335
Event Time Zone Mountain Standard Time
Event City TUCSON
Event State ARIZONA
Event Country --
Zipcode of the event site 85706
Event Date Year 1999
Event Date Month 6
MidAir Collision Indicator No
On Ground Collision occurred ? No
Event Location Latitude --
Event Location Longitude --
Event Location Airport TUCSON INTERNATIONAL
Event Location Nearest Airport ID TUS
Indicates whether the acc/inc occurred off or on an airport Off Airport/Airstrip
Distance from airport in statute miles --
Degrees magnetic from airport 210
Airport Elevation 2643
Weather Briefing Completeness Not pertinent
Investigator's weather source Weather Observation Facility
Time of the weather observation 1335 Mountain Standard Time
Direction of event from weather observation facility (degrees) 77
Weather Observation Facility ID TUC
Elevation of weather observation facility 2643
Distance of event from weather observation facility (units?) 0
Time Zone of the weather observation MST
Lighting Conditions Day
Lowest Ceiling Height 0
Lowest Non-Ceiling Height 10000
Sky/Lowest/Cloud Conditions Scattered
Sky Condition for Lowest Ceiling None
Visibility Runway Visual Range (Feet) 0
Visibility Runway Visual Value (Statute Miles) 0
Visibility (Statute Miles) 10
Air Temperature at event time (in degrees celsius) 36
Dew Point at event time (in degress fahrenheit) 8
Wind Direction (degrees magnetic) 150
Variable Wind Indicator Unknown
Wind Speed (knots) 3
Wind Velocity Indicator Unknown
Wind Gust Indicator Not Gusting
Wind Gust (knots) 0
Altimeter Setting at event time (in. Hg) 29
Density Altitude (feet) 5579
Intensity of Precipitation Unknown
METAR weather report --
Event Highest Injury Serious
On Ground, Fatal Injuries 0
On Ground, Minor Injuries 0
On Ground, Serious Injuries 0
Injury Total Fatal --
Injury Total Minor --
Injury Total None --
Injury Total Serious 1
Injury Total All 1
Investigating Agency NTSB
NTSB Docket Number (internal use) 1939
NTSB Notification Source --
NTSB Notification Date Jun 15 1999 12:00AM
NTSB Notification Time 1400
Fiche Number and/or location -used to find docket information IMAGE
Date of most recent change to record May 25 2001 4:45AM
User who most recently changed record dbo
Basic weather conditions Visual Meteorological Cond
FAA District Office --

Aircraft Involved

Aircraft #1

Aircraft Registration Number N6187C
NTSB Number LAX99GA216
Missing Aircraft Indicator N
Federal Aviation Reg. Part Part 91: General Aviation
Type of Flight Plan filed None
Flight plan Was Activated? --
Damage Destroyed
Aircraft Fire None
Aircraft Explosion None
Aircraft Manufacturer's Full Name Hughes
Aircraft Model OH-6A
Aircraft Series Identifier OH-6A
Aircraft Serial Number 68-17154
Certified Max Gross Weight 2550
Aircraft Category Helicopter
Aircraft Registration Class U.S. Registered/U.S. Soil
Aircraft is a homebuilt? No
Flight Crew Seats --
Cabin Crew Seats --
Passenger Seats --
Total number of seats on the aircraft 4
Number of Engines 1
Fixed gear or retractable gear Fixed
Aircraft, Type of Last Inspection Continuous Airworthiness
Date of Last Inspection Jun 7 1999 12:00AM
Airframe hours since last inspection 26
Airframe Hours 7176
ELT Installed Yes
ELT Activated Unknown
ELT Aided Location of Event Site No
ELT Type --
Aircraft Owner Name U.S. DEPARTMENT OF JUSTICE
Aircraft Owner Street Address 2021 EAST AIRPORT DRIVE
Aircraft Owner City TUCSON
Aircraft Owner State AZ
Aircraft Owner Country
Aircraft Owner Zipcode 85706
Operator is an individual? --
Operator Name
Operator Same as Owner? Yes
Operator Is Doing Business As --
Operator Address Same as Owner? Yes
Operator Street Address
Operator City
Operator State
Operator Country
Operator Zip code
Operator Code
Owner has at least one certificate None
Other Operator of large aircraft? No
Certified for Part 133 or 137 Operation Unknown
Operator Certificate Number --
Indicates whether an air carrier operation was scheduled or not --
Indicates Domestic or International Flight --
Operator carrying Pax/Cargo/Mail --
Type of Flying (Per_Bus / Primary) Public Use
Second Pilot on Board No
Departure Point Same as Event No
Departure Airport Code E78
Departure City SELLS
Departure State AZ
Departure Country
Departure Time 0
Departure Time Zone
Destination Same as Local Flt crash at destination city
Destination Airport Code TUC
Destination City
Destination State
Destination Country
Specific Phase of Flight Approach
Report sent to ICAO? --
Evacuation occurred --
Date of most recent change to record May 24 2001 8:43AM
User who most recently changed record dbo
Since inspection or accident --
Event Location Runway Number and Location 3
Runway Length 7000
Runway Width 150
Sight Seeing flight No
Air Medical Flight No
Medical Flight --