# NTSB LAX93LA367: Robinson R-22 Beta, N2407X, Livermore, CA, September 23, 1993 - Type: NTSB accident investigation - Classification: Accident · Minor injuries · Limited investigation · Final report - Date: September 23, 1993, 15:10 local (22:10 UTC) - Place: Livermore, CA - Coordinates: 37.679389, -121.749107 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=37.6794&lon=-121.7491&mi=10 - Phase of flight: [Maneuvering](https://openairdocs.org/ntsb-phases/450) (OpenAirDocs' grouping) - Highest injury: Minor injuries - Injuries: 2 minor - Status: Completed, report August 1, 1994 - Report: Approved by Office Director - NTSB case key (mKey): 28488 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=LAX93LA367 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/28488/pdf - Page: https://openairdocs.org/ntsb/LAX93LA367 ## Probable cause A partial engine power loss that resulted in a hard landing due to the engine primer system becoming unlocked. ## Sequence of events In NTSB's coding before 2008 (https://www.ntsb.gov/GILS/Documents/codman.pdf). - Loss of engine power(partial) - nonmechanical, hover - fuel system,primer system - unlocked (cause) - Forced landing, descent - emergency - Hard landing, descent - emergency ## Analysis THE PILOT HAD STABILIZED THE AIRCRAFT IN A HOVER AND WAS DESCENDING FOR LANDING FROM ABOUT 30 FEET AGL. THE ENGINE SUDDENLY LOST POWER AND THE RATE OF DESCENT INCREASED. THE PILOT ATTEMPTED TO ADD FORWARD CYCLIC TO PERFORM A RUNNING LANDING. THE HELICOPTER LANDED HARD IN A LEVEL ATTITUDE COLLAPSING THE SKIDS AND DAMAGING THE ROTORS AND FUSELAGE. INSPECTION OF THE ENGINE PRIMER SYSTEM DISCLOSED THAT THE PRIMER HANDLE WAS UNLOCKED. THE PRIMER HAD UNLOCKED ON THIS HELICOPTER ON TWO PREVIOUS OCCASIONS. ## Factual narrative On September 23, 1993, about 1510 hours Pacific daylight time, a Robinson R22-Beta, N2407X, crashed during landing at Livermore Municipal Airport, Livermore, California. The helicopter was being operated as a visual flight rules (VFR) local area photo flight when the accident occurred. The helicopter, operated by Tri Valley Helicopters, sustained substantial damage. The certificated pilot and a passenger received minor injuries. Visual meteorological conditions prevailed. The flight originated at the Livermore Airport at 1445 hours. The pilot reported that he was preparing to land and began a steep approach to a landing pad from about a 45-foot above ground level (AGL) hover. About 25 feet AGL, the helicopter's engine began losing power. The pilot ensured that the throttle was full open and reduced collective pitch and applied forward cyclic to attempt a running landing. The pilot reported that his rate of descent was about 300 feet per minute. The helicopter contacted an asphalt airport ramp in a level attitude with about 20 knots of airspeed. The helicopter received damage to the landing gear skids, tail boom, rotor blades, and fuselage. The pilot reported that during his preflight inspection of the helicopter, he observed the engine primer "IN" and "LOCKED". After the accident, the pilot reported that the primer was found unlocked and an inspection of the lower spark plugs revealed that they were fouled. In addition, the pilot said that the accident helicopter had two previous cases of the primer becoming unlocked. The first occured during an engine run up, and a second occurred during a flight in which the pilot made a precautionary landing. An operations inspector, Federal Aviation Administration, Oakland Flight Standards District Office, inspected the helicopter. He reported that the primer is an optional engine item and is installed under and forward of the right seat cushion. His inspection of the primer also revealed that it was unlocked. The helicopter and engine had accumulated a total time in service of 1,631.6 flight hours. Examination of the maintenance records revealed that the most recent annual inspection was accomplished on June 2, 1993, 239.6 flight hours before the accident. In addition, a 100-hour inspection was completed on September 6, 1993, 33.6 hours before the accident. ## Aircraft - Registration: [N2407X](https://openairdocs.org/deregistered/N2407X-1994-08-25), registration cancelled 1994-08-25, S/N 1883 (OpenAirDocs) - Reported make and model: ROBINSON R-22 BETA - Registry model: [Robinson Helicopter R22 BETA](https://openairdocs.org/model/robinson-helicopter-r22-beta) (registry code 7640110) (OpenAirDocs) - Category: Helicopter - Serial number: 1883 - Airframe hours: 1632 - Engines: LYCOMING O-320-B2C 160 horsepower reciprocating - Damage: Substantial damage - Flight: Part 91 - Operator: Tri Valley Helicopters - Registered owner: Brady, Howard N., Jr. - Airworthiness certificate: Standard, Normal - Last inspection: 100 hour, September 6, 1993, 34 hours before - Airport: LVK, Livermore ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 42; commercial, flight instructor, private; airplane ratings: single-engine land; medical: class 2, valid medical--no waivers/lim.; seat: right; flight hours: 2,160 total, 200 as pilot in command, 94 in the last 90 days, 50 in the last 30 days ## Weather - Conditions: Visual (VMC), Day - Wind: 360° at 10 knots - Visibility: 30 statute miles - Lowest ceiling: none - Temperature: 82 °F - Altimeter: 29.00 inHg - Observed at: LVK ## FAA reports on this event (1) The FAA's own accident and incident reports, matched to the aircraft by N-number and date (OpenAirDocs). - [Accident 19930923036229A](https://openairdocs.org/incident/19930923036229A), Sep 23, 1993: Robsin R22BETA, Livermore, CA, Substantial damage. Landing from hover engine lost power. Attempt divert to run landing. Landed hard. Collapsed skids. Primer unlocked. From the NTSB's public API. Aircraft are matched to registry aircraft by N-number and event date, checked against the reported serial number, make and model; the registry's history has gaps, so older matches can be wrong. Compare the reported make and model. --- OpenAirDocs.org is an independent research project of [Contrail Labs](https://contraillabs.com/). It is not affiliated with the FAA or the NTSB. Source documents are U.S. government works in the public domain.