# NTSB BFO94LA035: Robinson R-22A, N8559A, Gaithersburg, MD, January 25, 1994 - Type: NTSB accident investigation - Classification: Accident · No injuries · Limited investigation · Final report - Date: January 25, 1994, 16:05 local (21:05 UTC) - Place: Gaithersburg, MD - Coordinates: 39.169742, -77.180809 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=39.1697&lon=-77.1808&mi=10 - Phase of flight: [Maneuvering](https://openairdocs.org/ntsb-phases/450) (OpenAirDocs' grouping) - Highest injury: No injuries - Injuries: 1 uninjured - Status: Completed, report January 26, 1995 - Report: Approved by Office Director - NTSB case key (mKey): 8885 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=BFO94LA035 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/8885/pdf - Page: https://openairdocs.org/ntsb/BFO94LA035 ## Probable cause THE PILOT'S FAILURE TO MAINTAIN ROTOR RPM WHICH LED TO AN IN FLIGHT LOSS OF CONTROL RESULTING IN A COLLISION WITH THE RUNWAY AND THE HELICOPTER ROLLING OVER ON ITS SIDE. A FACTOR IN THIS ACCIDENT WAS THE PILOT'S LACK OF TOTAL EXPERIENCE FLYING HELICOPTERS. ## Sequence of events In NTSB's coding before 2008 (https://www.ntsb.gov/GILS/Documents/codman.pdf). - Loss of control - in flight, hover - rotor rpm - not maintained, pilot in command (cause) - lack of total experience in type of aircraft, pilot in command (contributing factor) - In flight collision with terrain/water, descent - uncontrolled - terrain condition - runway - Roll over, descent - uncontrolled ## Analysis The pilot was in the process of being trained to fly helicopters and did not have a helicopter rating. The pilot had accumulated about 19 hours of total helicopter flight time when the accident occurred. He did possess a private pilot fixed wing certificate at the time of the accident. The pilot was performing a supervised solo and was hovering over the runway at the termination of his fourth approach. He said the low RPM light illuminated and he lowered the collective. He lost control of the helicopter and it descended to the runway. The helicopter bounced on both skids and returned to the runway. The helicopter's left skid contacted the runway and the helicopter rolled over. ## Factual narrative On January 25, 1994 about 1605 hours eastern standard time, a Robinson R-22A, N8559A entered an uncontrolled descent from hovering flight, collided with the runway, and rolled over at Gaithersburg Airport, Gaithersburg, Maryland. The helicopter sustained substantial damage and the certificated private pilot was not injured. The local area instructional flight was being operated by Montgomery Aviation, Limited at the time. Visual meteorological conditions prevailed and a flight plan was not filed. According to an FAA safety inspector, at the time of the accident, the pilot had a private pilot certificate with a single engine airplane rating. The pilot was in the process of being trained to fly helicopters and did not have a helicopter rating. The FAA safety inspector examined the helicopter after the accident and did not find any pre-existing anomalies. In his written statement, the pilot said that during his supervised solo flight, he made his fourth approach to the runway and then began to hover the helicopter. He said the low RPM warning light illuminated and he "...rolled throttle and lowered collective, nose yawed left and gained altitude. Lowered collective (I believe) and left skid touched ground. Bounced on both skids and returned on ground on left skid. Then started dynamic rollover." Neither the pilot nor the operator reported any pre-existing deficiencies for the helicopter prior to the accident. ## Aircraft - Registration: [N8559A](https://openairdocs.org/deregistered/N8559A-1999-06-24), registration cancelled 1999-06-24, S/N 0468 (OpenAirDocs) - Reported make and model: ROBINSON R-22A - Registry model: [Robinson Helicopter R22 ALPHA](https://openairdocs.org/model/robinson-helicopter-r22-alpha) (registry code 7640104) (OpenAirDocs) - Category: Helicopter - Serial number: 468 - Airframe hours: 3867 - Engines: LYCOMING O-320-B2C 160 horsepower reciprocating - Damage: Substantial damage - Flight: Instructional, Part 91 - Operator: Montgomery Aviation - Registered owner: David Carr - Airworthiness certificate: Standard, Normal - Last inspection: 100 hour, January 9, 1994, 40 hours before - Airport: GAI, Montgomery Airpark, runway 14, 4,196 × 73 ft, asphalt ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 24; private; airplane ratings: single-engine land; medical: class 3, valid medical--no waivers/lim.; seat: right; flight hours: 95 total, 19 in this make and model, 52 as pilot in command, 24 in the last 90 days, 7 in the last 30 days, 1 in the last 24 hours ## Weather - Conditions: Visual (VMC), Day - Wind: 140° at 5 knots - Visibility: 10 statute miles - Lowest ceiling: none - Temperature: 36 °F - Altimeter: 29.00 inHg ## 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 19940125000869A](https://openairdocs.org/incident/19940125000869A), Jan 25, 1994: Robsin R22ALPHA, Gaithersburg, MD, Substantial damage. On departing airport, experienced low RPM warning horn. Tried to recover. Touched runway on left skid and rolled. (.4)the pilot was in the process of being… ## Other investigations on N8559A (1) 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. - [NTSB BFO88LA076](https://openairdocs.org/ntsb/BFO88LA076), Aug 27, 1988: Robinson R22A (N8559A), Gaithersburg, MD, substantial damage 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.