# NTSB ERA16LA014: Gross Michael E Stol CH 701, N4931M, Eufala, AL, October 14, 2015 - Type: NTSB accident investigation - Classification: Accident · No injuries · Limited investigation · Final report - Date: October 14, 2015, 14:45 local (19:45 UTC) - Place: Eufala, AL - Coordinates: 31.951389, -85.12889 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=31.9514&lon=-85.1289&mi=10 - Phase of flight: [Initial climb](https://openairdocs.org/ntsb-phases/350) (OpenAirDocs' grouping) - Defining event: [Initial climb: Loss of control in flight](https://openairdocs.org/ntsb-events/240) - Highest injury: No injuries - Injuries: 1 uninjured - Status: Completed, report January 25, 2018 - Report: Approved by Office Director - NTSB office: Eastern Region Aviation - Parties: FAA/FSDO - NTSB case key (mKey): 92181 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=ERA16LA014 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/92181/pdf - NTSB docket: https://data.ntsb.gov/Docket?ProjectID=92181 - Page: https://openairdocs.org/ntsb/ERA16LA014 ## Probable cause A partial loss of engine power during takeoff for reasons that could not be determined, because postaccident examination revealed no evidence of any preimpact mechanical malfunctions or failures. Also causal was the pilot's decision to continue the takeoff following the loss of power. ## Findings NTSB's coded findings; those marked are part of the probable cause. - [Performance/control parameters: pitch control](https://openairdocs.org/ntsb-findings/01062022): Aircraft › Aircraft oper/perf/capability · Incorrect use/operation; cases with it: [Gross Michael E STOL CH 701, 1 case](https://openairdocs.org/ntsb-findings/01062022/cases.md?model=05622HD), [All aircraft, 526 cases](https://openairdocs.org/ntsb-findings/01062022/cases.md) - [Performance/control parameters: angle of attack](https://openairdocs.org/ntsb-findings/01062042): Aircraft › Aircraft oper/perf/capability · Capability exceeded; cases with it: [Gross Michael E STOL CH 701, 1 case](https://openairdocs.org/ntsb-findings/01062042/cases.md?model=05622HD), [All aircraft, 990 cases](https://openairdocs.org/ntsb-findings/01062042/cases.md) - [Action: incorrect action performance](https://openairdocs.org/ntsb-findings/02041015): Personnel issues › Action/decision · Pilot (probable cause); cases with it: [Gross Michael E STOL CH 701, 1 case](https://openairdocs.org/ntsb-findings/02041015/cases.md?model=05622HD), [All aircraft, 1,386 cases](https://openairdocs.org/ntsb-findings/02041015/cases.md) ## Sequence of events The events NTSB coded, in order, by phase of flight. The defining event best describes what happened. - [Initial climb: Loss of control in flight](https://openairdocs.org/ntsb-events/240) (defining event); cases with it: [Gross Michael E STOL CH 701, 1 case](https://openairdocs.org/ntsb-events/240/sequence.md?model=05622HD), [All aircraft, 5,002 cases](https://openairdocs.org/ntsb-events/240/sequence.md) ## Analysis The private pilot had purchased the airplane a day earlier and, while flying it back to his home airport, stopped at an en route airport to refuel. The pilot stated that, about midfield during the takeoff, the engine began to run roughly and vibrate, was not producing full power, and the flight controls "got mushy." Shortly after the takeoff, at an altitude of 50 ft, the airplane veered to the left, impacted the ground, and nosed over. The pilot noted that the airplane took longer to take off due to a crosswind; however, weather recorded at the airport 13 minutes after the accident included calm winds. Postaccident examination of the airframe and engine revealed no evidence of any preexisting mechanical anomalies that would have precluded normal operation, and the reason for the loss of engine power could not be determined. ## Factual narrative On October 14, 2015, about 1445 central daylight time, an experimental amateur-built Zenith STOL CH701, N4931M, was substantially damaged shortly after taking off from Weedon Field (EUF), Eufala, Alabama. The private pilot was not injured. Visual meteorological conditions prevailed, and no flight plan had been filed for the flight to Eu-Wish Airport (MU68), Hermann, Missouri. The personal flight was operating under the provisions of 14 Code of Federal Regulations Part 91.After the accident, the pilot was granted permission by the NTSB investigator in charge to transport the airplane to his home in Missouri, being advised that additional information would be requested. The pilot subsequently failed to respond to any NTSB information requests, either directly or through his attorney. The investigation could thus only rely on the information gathered onsite by the responding Federal Aviation Administration (FAA) inspector, and on a written statement from the pilot subsequently provided through his attorney to the FAA inspector. According to the pilot, he had purchased the airplane the day before in Florida, and was flying it home to Missouri, stopping at EUF to refuel. After refueling, the engine would not start, and the battery discharged. After charging the battery, the engine started "normally." In a written statement the day of the accident, the pilot stated that after takeoff, about 50 feet above the runway, the airplane "turned left and did not respond to any control inputs to trim right and stay over the runway. Instead, it continued a left bank and impacted the ground." In a later statement, the pilot stated that he had performed an engine run-up at 4,000 rpm without noting any anomalies. After which, he taxied to south end of runway 36 and commenced the takeoff. After applying full power, the airplane took longer than normal to take off due to crosswind conditions. About 50 feet above the runway, at mid-field, the engine began to run roughly and vibrate, and was not producing full power. The pilot attempted to "smooth out" the engine by adjusting the throttle; there was no mixture control. The pilot then attempted to land the airplane back on the runway, but in the process, it veered off the left side and flipped upside-down. The pilot egressed the airplane, and reached back in to turn off the fuel valve as the emergency vehicles arrived. According to the responding FAA inspector, the airplane had been moved to a hangar prior to her arrival. There, she noted that one blade of the three-bladed composite propeller was broken off and one was cracked. There was no bending or twisting of the propeller blades. There was no dripping or splattering of oil on the engine cowling. No anomalies were noted within the engine compartment. The fuel bowl on the left side of the engine was full, and both wing fuel tanks were full of fuel. The inspector also drained fuel from each of the two wing tanks, and the fuel sump on the underside of the fuselage,just aft the engine compartment, and all samples were "clear and clean." The inspector noted no control binding to the elevator or rudder, and while checking for aileron binding (none noted), the pilot stated that the controls "got mushy." The FAA inspector subsequently drove out along the runway to where the airplane was recovered, which was about 3,200 feet from the departure end of the 5,000-foot runway. Weather, recorded at the airport 13 minutes after the accident, included clear skies and calm winds. ## Aircraft - Registration: [N4931M](https://openairdocs.org/deregistered/N4931M-2016-02-12), registration cancelled 2016-02-12, S/N 7-4931, built 2006 (OpenAirDocs) - Reported make and model: GROSS MICHAEL E STOL CH 701 - Registry model: [Gross Michael E STOL CH 701](https://openairdocs.org/model/gross-michael-e-stol-ch-701) (registry code 05622HD) (OpenAirDocs) - Registry engine: [Rotax 912UL series](https://openairdocs.org/engine/rotax-912ul-series) (registry code 55571, 4 cycle) (OpenAirDocs) - Category: Airplane, amateur-built - Serial number: 7-4931 - Year built: 2006 - Airframe hours: 738 - Engines: ROTAX 912UL reciprocating - Damage: Substantial damage - Flight: Personal, Part 91 - Airworthiness certificate: Special, Experimental (Special) - Last inspection: Annual, February 11, 2015, 25 hours before - Departed: EUF, Eufala, AL - Destination: MU68, Hermann, MO - Airport: EUF, Weedon Field, runway 36, 5,000 × 100 ft, asphalt ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 66; injuries: none; sport pilot, private; airplane ratings: single-engine land; last flight review October 10, 2015; seat: left; flight hours: 218 total, 6 in this make and model, 8 in the last 90 days, 6 in the last 24 hours ## Weather - Conditions: Visual (VMC), Day - Wind: calm - Visibility: 10 statute miles - Lowest ceiling: none - Temperature: 82 °F, dew point 48 °F - Altimeter: 29.98 inHg - Observed at: EUF ## 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 20151014017439A](https://openairdocs.org/incident/20151014017439A), Oct 14, 2015: Gross Michael E STOL CH 701, Eufaula, AL, Substantial damage. Pilot completed a normal run-up. Pilot departed runway 36. Pilot states, that during climbout at approximately 50 feet AGL the engine began to run roughly and… ## Docket (3 files) The files NTSB released with the investigation on October 31, 2017, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=92181. 1.8 MB in all. - FAA Inspector - Supplied Documents (item 1, .PDF, 1.2 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40457501&FileExtension=.PDF&FileName=FAA%20Inspector%20-%20Supplied%20Documents-Master.PDF - Pilot Statement (item 2, .PDF, 254 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40457502&FileExtension=.PDF&FileName=Pilot%20Statement-Master.PDF - Memorandum for Record - Attemps for Information (item 3, .PDF, 323 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40457503&FileExtension=.PDF&FileName=Memorandum%20for%20Record%20-%20Attemps%20for%20Information-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.