# NTSB MIA99LA017: Reinhold Revolution Mini 500, N500GQ, Hickory, NC, October 26, 1998 - Type: NTSB accident investigation - Classification: Accident · No injuries · Limited investigation · Final report - Date: October 26, 1998, 15:15 local (20:15 UTC) - Place: Hickory, NC - Coordinates: 35.770591, -81.329452 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=35.7706&lon=-81.3295&mi=10 - Phase of flight: [Enroute](https://openairdocs.org/ntsb-phases/400) (OpenAirDocs' grouping) - Highest injury: No injuries - Injuries: 1 uninjured - Status: Completed, report August 27, 1999 - Report: Approved by Office Director - NTSB case key (mKey): 45171 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=MIA99LA017 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/45171/pdf - Page: https://openairdocs.org/ntsb/MIA99LA017 ## Probable cause The seizure of the rear piston in the cylinder barrel resulting in total loss of engine power and an autorotation which resulted in main rotor contact with the tail boom while touching down on unsuitable terrain. ## Sequence of events In NTSB's coding before 2008 (https://www.ntsb.gov/GILS/Documents/codman.pdf). - Loss of engine power(total) - mech failure/malf, cruise - normal - engine assembly,piston - seized (cause) - Forced landing, emergency descent/landing - autorotation - performed, pilot in command - Miscellaneous/other, emergency descent/landing - terrain condition - none suitable - terrain condition - high vegetation - misc rotorcraft,main rotor/tail boom contact ## Analysis The pilot stated the engine lost power without warning while in cruise flight between 500-700 feet. An autorotaion was made to a clear area with high vegetation. During touchdown on the previously unnoticed uneven terrain, the main rotor hit the mechanical stop and contacted the tailboom. The helicopter then spun around 180 degrees and came to rest. Postcrash examination of the engine showed the rear cylinder had seized in the barrel. The pilot stated this was the second time this had happened. The engine had accumulated 46 hours since being rebuilt after the previous failure. ## Factual narrative On October 26, 1998, about 1515 eastern standard time, a Reinhold Revolution Mini 500, N500GQ, registered to an individual, crashed while making a forced landing following loss of engine power near Hickory, North Carolina, while on a Title 14 CFR Part 91 personal flight. Visual meteorological conditions prevailed at the time and no flight plan was filed. The helicopter received substantial damage and the airline transport-rated pilot was not injured. The flight originated from Hickory, North Carolina, the same day, about 1600. The pilot stated that while in cruise flight at between 500-700 feet, the engine quit with no prior warning. He initiated an autorotation and made a left turn toward a clearing. Upon touchdown on uneven terrain, the main rotor hit the mechanical stop and then contacted the tailboom. The helicopter spun around to the left 180 degrees and came to rest on the back skids and engine muffler. The clear area he selected for the landing was overgrown with about 6 feet of vegetation. Postcrash examination of the engine by the pilot showed the rear piston had seized in the barrel. The pilot stated to NTSB that this was the second time this has happened in this helicopter. The engine had accumulated about 46 flight hours since it was rebuilt after the previous piston seizure. ## Aircraft - Registration: [N500GQ](https://openairdocs.org/deregistered/N500GQ-2000-08-08), registration cancelled 2000-08-08, S/N 404 (OpenAirDocs) - Reported make and model: Reinhold REVOLUTION MINI 500 (REVOLUTION) - Registry model: [Grauer Reinhold REVOLUTION MINI 500](https://openairdocs.org/model/grauer-reinhold-revolution-mini-500) (registry code 056043L) (OpenAirDocs) - Category: Helicopter, amateur-built - Serial number: 404 - Airframe hours: 69 - Engines: Rotax 582 67 horsepower reciprocating - Damage: Substantial damage - Flight: Personal, Part 91 - Registered owner: Grauer Reinhold - Airworthiness certificate: Special, Experimental (Special) - Last inspection: Annual, March 15, 1998, 38 hours before - Departed: WEDDINGTON, NC ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 39; flight instructor, airline transport, flight engineer; airplane ratings: multi-engine land, single-engine land; instrument ratings: airplane; medical: class 1, valid medical--no waivers/lim.; seat: center; flight hours: 11,600 total, 69 in this make and model, 4,000 as pilot in command, 210 in the last 90 days, 70 in the last 30 days, 2 in the last 24 hours ## Weather - Conditions: Visual (VMC), Day - Wind: calm - Visibility: 10 statute miles - Lowest ceiling: none - Temperature: 75 °F, dew point 39 °F - Altimeter: 30.00 inHg - Observed at: HKY, 1 nm away ## 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 19981026030419A](https://openairdocs.org/incident/19981026030419A), Oct 26, 1998: Amtr MINI500, Hickory, NC, Substantial damage. Helicopter engine failed, the acft made an emergency landing in a field, and the tail boom sustained damage. (-23) grauer stated, he was flying over rhodhiss… 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.