# NTSB CEN15LA132: Butler Raymond Rotorway Exec 162F, N162RB, Seadrift, TX, January 31, 2015 - Type: NTSB accident investigation - Classification: Accident · No injuries · Limited investigation · Final report - Date: January 31, 2015, 14:45 local (20:45 UTC) - Place: Seadrift, TX - Coordinates: 28.521667, -96.798332 - Nearby events: https://openairdocs.org/map.md?lat=28.5217&lon=-96.7983&mi=10 - Phase of flight: [Enroute](https://openairdocs.org/ntsb-phases/400) (OpenAirDocs' grouping) - Defining event: [Enroute-cruise: Loss of engine power (total)](https://openairdocs.org/ntsb-events/341) - Highest injury: No injuries - Injuries: 2 uninjured - Status: Completed, report July 13, 2015 - Report: Approved by Office Director - NTSB office: Central Region - NTSB case key (mKey): 90676 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=CEN15LA132 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/90676/pdf - NTSB docket: https://data.ntsb.gov/Docket?ProjectID=90676 - Page: https://openairdocs.org/ntsb/CEN15LA132 ## Probable cause A fault in the No. 1 engine control module, which disabled the ignition system and resulted in the engine losing power; during the subsequent autorotation, the main rotor rpm was further reduced just before touchdown, which resulted in a hard landing. ## Findings NTSB's coded findings; those marked are part of the probable cause. - [Electrical power system: dC generation system](https://openairdocs.org/ntsb-findings/01022430): Aircraft › Aircraft systems · Failure (probable cause); cases with it: [Butler Raymond ROTORWAY EXEC 162F, 1 case](https://openairdocs.org/ntsb-findings/01022430/cases.md?model=05621ZX), [All aircraft, 6 cases](https://openairdocs.org/ntsb-findings/01022430/cases.md) - [Engine (reciprocating)](https://openairdocs.org/ntsb-findings/01058500): Aircraft › Aircraft power plant · Failure (probable cause); cases with it: [Butler Raymond ROTORWAY EXEC 162F, 1 case](https://openairdocs.org/ntsb-findings/01058500/cases.md?model=05621ZX), [All aircraft, 497 cases](https://openairdocs.org/ntsb-findings/01058500/cases.md) ## Sequence of events The events NTSB coded, in order, by phase of flight. The defining event best describes what happened. - [Enroute-cruise: Loss of engine power (total)](https://openairdocs.org/ntsb-events/341) (defining event); cases with it: [Butler Raymond ROTORWAY EXEC 162F, 1 case](https://openairdocs.org/ntsb-events/341/sequence.md?model=05621ZX), [All aircraft, 3,820 cases](https://openairdocs.org/ntsb-events/341/sequence.md) - [Autorotation: Off-field or emergency landing](https://openairdocs.org/ntsb-events/440); cases with it: [Butler Raymond ROTORWAY EXEC 162F, 1 case](https://openairdocs.org/ntsb-events/440/sequence.md?model=05621ZX), [All aircraft, 3,365 cases](https://openairdocs.org/ntsb-events/440/sequence.md) ## Analysis The pilot reported that the experimental, amateur-built helicopter was at 300 ft above ground level (agl) when the low rotor rpm horn sounded and the engine lost power. The pilot entered an autorotation and arrested the descent rate. When the helicopter was about 8 ft agl over tall grass, the main rotor speed further decelerated. The helicopter landed hard while it was still moving forward at high speed, which resulted in the landing gear separating. The engine had been modified with a full authority digital electronic control (FADEC) system. Following the accident, the pilot tested the FADEC system and determined that the loss of engine power was caused by a fault in the No. 1 engine control module (ECM); every time the No. 1 ECM was turned on, the engine would quit; however, if the No. 1 ECM was turned off and the No. 2 ECM was turned on, the engine would operate. Although the helicopter was equipped with two ECMs, which should have provided redundant operation, it was determined that a single-point failure of the No. 1 ECM resulted in the engine failure. ## Factual narrative On January 31, 2015, about 1445 central standard time, an experimental amateur-built Rotorway Exec 162F, N162RB, landed hard during an emergency autorotation near Seadrift, Texas. The pilot and his passenger were not injured. The helicopter was substantially damaged. The helicopter was registered to and operated by the pilot under the provisions of 14 Code of Federal Regulations Part 91 as a personal flight. Visual meteorological conditions prevailed at the time of the accident, and no flight plan had been filed. The local flight originated from Port Lavaca, Texas, about 1420.The pilot said they were flying at about 300 feet above ground level and were returning to Port Lavaca after a 25 minute sightseeing flight. The LOW ROTOR RPM horn sounded and the engine had lost power. The pilot entered an autorotation and picked a landing spot. He arrested the rate of descent but the helicopter had too much forward speed to set down vertically. As he maneuvered the helicopter into some tall heavy grass about 8 feet above the ground, the main rotor speed decelerated below the minimum safe rpm. The pilot said the helicopter was still moving forward at high speed and, as such, it landed hard, tearing off the landing gear. According to the pilot, the stock Rotorway engine had been highly modified. An after-market Full Authority Digital Electronic Control (FADEC) system, designed specifically for the engine, had been installed. The FADEC system consisted of two separate and redundant Engine Control Modules (ECMs). On one occasion, the engine failed to start after the pilot had made a brief flight. He determined that there was a fault in the No. 1 ECM. Both ECMs were sent to the manufacturer for examination and testing. No problems were identified and they were returned to the pilot. He made four additional uneventful flights, totaling more than 3 hours, before the accident flight. After the accident, the pilot examined and tested the ignition system since the manufacturer was no longer in business. With both ECMs on, the engine was started and ran normally. When the No. 1 ECM was switched off, the engine continued to run on the No. 2 ECM. When the No. 1 ECM was switched back on, the engine quit. The only way the engine would start was to turn on the No. 2 ECM and leave the No. 1 ECM off. Every time the No. 1 ECM was switched on, the engine would quit. The pilot switched the wiring harnesses and established that the problem followed the No. 1 ECM. He determined the fault lay solely in the No. 1 ECM. ## Aircraft - Registration: [N162RB](https://openairdocs.org/deregistered/N162RB-2019-09-06), registration cancelled 2019-09-06, S/N 6873, built 2008 (OpenAirDocs) - Reported make and model: BUTLER RAYMOND ROTORWAY EXEC 162F (NO SERIES) - Registry model: [Butler Raymond ROTORWAY EXEC 162F](https://openairdocs.org/model/butler-raymond-rotorway-exec-162f) (registry code 05621ZX) (OpenAirDocs) - Registry engine: [Rotorway RI-162F](https://openairdocs.org/engine/rotorway-ri-162f) (registry code 55007, 4 cycle) (OpenAirDocs) - Category: Helicopter, amateur-built - Serial number: 6873 - Year built: 2008 - Engines: ROTORWAY RI 162F 152 horsepower reciprocating - Damage: Substantial damage - Flight: Personal, Part 91 - Operator: Butler William Raymond - Registered owner: Butler William Raymond - Airworthiness certificate: Special, Experimental (Special) - Last inspection: 100 hour, September 1, 2014, 140 hours before - Departed: NONE, Port Lavaca, TX - Destination: NONE, Port Lavaca, TX ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 62; injuries: none; private; airplane ratings: single-engine land; instrument ratings: airplane; medical: class 3, with waivers/limitations; seat: left; restraint: 3-point; flight hours: 3,000 total, 350 in this make and model ## Weather - Conditions: Visual (VMC), Day - Wind: 120° at 14 knots - Visibility: 10 statute miles - Lowest ceiling: 1,900 ft broken - Temperature: 66 °F, dew point 63 °F - Altimeter: 30.01 inHg - Observed at: KPKV, 15 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 20150131002929A](https://openairdocs.org/incident/20150131002929A), Jan 31, 2015: Butler Raymond ROTORWAY EXEC 162F, Sea Drift, TX, Substantial damage. Pilot stated he was returning home, flying at about 300 feet altitude, in VFR conditions, when he heard the low rotor RPM horn start blaring, felt the… ## Docket (7 files) The files NTSB released with the investigation on April 28, 2015, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=90676. 7.8 MB in all. - Pilot's Accident Report and Related E-Mails (item 1, .PDF, 120 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40425623&FileExtension=.PDF&FileName=Pilot%27s%20Accident%20Report%20and%20Related%20E-Mails-Redacted.PDF - Google Earth View of Accident Site, Seadrift, TX (item 2, .PDF, 199 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40425641&FileExtension=.PDF&FileName=Google%20Earth%20View%20of%20Accident%20Site,%20Seadrift,%20TX-Master.PDF - Weather Reports and Records (item 3, .PDF, 85 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40425626&FileExtension=.PDF&FileName=Weather%20Reports%20and%20Records-Master.PDF - Photo 1 - N162RB in tall grass at the accident site (item 4, .PDF, 338 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40425631&FileExtension=.PDF&FileName=Photo%201%20-%20N162RB%20in%20tall%20grass%20at%20the%20accident%20site-Master.PDF - Photo 2 - Closer view shows bent rotor blades and buckled skids (item 5, .PDF, 364 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40425628&FileExtension=.PDF&FileName=Photo%202%20-%20Closer%20view%20shows%20bent%20rotor%20blades%20and%20buckled%20skids-Master.PDF - Photo 3 - Rear view of helicopter and severed tail rotor assembly (item 6, .PDF, 3.7 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40425629&FileExtension=.PDF&FileName=Photo%203%20-%20Rear%20view%20of%20helicopter%20and%20severed%20tail%20rotor%20assembly-Master.PDF - Photo 4 - FADEC ignition system with the two ECMs (item 7, .PDF, 3.1 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40425630&FileExtension=.PDF&FileName=Photo%204%20-%20FADEC%20ignition%20system%20with%20the%20two%20ECMs-Master.PDF 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.