# NTSB ANC05LA032: Johnson Revolution Mini 500, N38DJ, Isabela, PR, February 12, 2005 - Type: NTSB accident investigation - Classification: Accident · Minor injuries · Limited investigation · Final report - Date: February 12, 2005, 15:40 local (20:40 UTC) - Place: Isabela, PR - Coordinates: 18.494722, -67.129447 - Nearby events: https://openairdocs.org/map.md?lat=18.4947&lon=-67.1294&mi=10 - Phase of flight: [Enroute](https://openairdocs.org/ntsb-phases/400) (OpenAirDocs' grouping) - Highest injury: Minor injuries - Injuries: 1 minor - Status: Completed, report December 20, 2005 - Report: Approved by Office Director - NTSB office: Alaska Regional Office - Parties: FAA San Juan PR - NTSB case key (mKey): 61005 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=ANC05LA032 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/61005/pdf - Page: https://openairdocs.org/ntsb/ANC05LA032 ## Probable cause The loss of engine power during cruise flight for an undetermined reason, which resulted in an autorotation and collision with terrain. ## Analysis The pilot was conducting a personal flight in a single-seat experimental helicopter under 14 CFR Part 91 when the helicopter had a loss of engine power. The pilot entered an autorotation to a construction site, and during the approach to land, he had to maneuver away from power lines. After clearing the power lines, the rotor rpm was too low to flare the helicopter, and it impacted the ground. The pilot said due to the extensive damage, he was not able to determine why the engine lost power. ## Factual narrative On February 12, 2005, about 1540 eastern standard time, an experimental amateur built Johnson Revolution Mini 500 helicopter, N38DJ, sustained substantial damage when it collided with terrain following a loss of engine power, and subsequent emergency descent and landing at Isabela, Puerto Rico. The helicopter was being operated by the pilot as a local visual flight rules (VFR) personal flight under Title 14, CFR Part 91, when the accident occurred. The solo private pilot received minor injuries. Visual meteorological conditions prevailed, and no flight plan was filed. During a telephone conversation with the National Transportation Safety Board (NTSB) investigator-in-charge (IIC) on February 13, the FAA aviation safety inspector who interviewed the pilot said the pilot told him the helicopter had a loss of engine power for an unknown reason. The pilot reported he attempted an autorotation to a building construction site, but had to maneuver hard to miss power lines. The pilot said that during the maneuver, the rotor rpm dropped, and he was unable to stop the descent prior to the collision with terrain. He said the helicopter sustained structural damage to the fuselage and rotor system. In a written statement to the NTSB dated May 19, the pilot said due to the extensive damage to the helicopter, he was unable to determine why the engine lost power. ## Sequence of events In NTSB's coding before 2008 (https://www.ntsb.gov/GILS/Documents/codman.pdf). - Loss of engine power, cruise - reason for occurrence undetermined (cause) - Forced landing, descent - emergency - autorotation - performed, pilot in command - In flight collision with terrain/water, emergency descent/landing - terrain condition - ground ## Aircraft - Registration: [N38DJ](https://openairdocs.org/deregistered/N38DJ-2005-05-04), registration cancelled 2005-05-04, S/N 321, built 1997 (OpenAirDocs) - Reported make and model: Johnson Revolution Mini 500 - Registry model: [Johnson Douglas C REVOLUTION MINI-500](https://openairdocs.org/model/johnson-douglas-c-revolution-mini-500) (registry code 05605HE) (OpenAirDocs) - Registry engine: [Bombardier ROTAX (ALL)](https://openairdocs.org/engine/bombardier-rotax-all) (registry code 09050, reciprocating) (OpenAirDocs) - Category: Helicopter, amateur-built - Serial number: 321 - Airframe hours: 125 - Engines: Rotax 582 67 horsepower reciprocating - Damage: Substantial damage - Flight: Personal, Part 91 - Registered owner: Neftail Valentin - Airworthiness certificate: Special, Experimental (Special) - Last inspection: Condition, February 1, 2005, 0 hours before - Departed: Vega Baja, PR ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 52; injuries: minor; private; medical: class 3, without waivers/limitations; last flight review March 1, 2004; seat: front; flight hours: 142 total, 51 in this make and model ## Weather - Conditions: Visual (VMC), Day - Visibility: 20 statute miles - Lowest ceiling: none - Temperature: 70 °F ## 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 20050212005139A](https://openairdocs.org/incident/20050212005139A), Feb 12, 2005: Amtr MINI500, Isabela, Puerto Rico, Destroyed. (-23) At 1210 on February 14, 2005, [privacy data omitted], pilot, accidented in Isabela on February 12, 2005, when his helicopter a revolution mini-500… 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.