# NTSB CEN15LA042: Mosier Robert S Mosquito XET, N922RM, Angleton, TX, November 8, 2014 - Type: NTSB accident investigation - Classification: Accident · Minor injuries · Limited investigation · Final report - Date: November 8, 2014, 10:00 local (16:00 UTC) - Place: Angleton, TX - Coordinates: 29.165, -95.401107 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=29.1650&lon=-95.4011&mi=10 - Phase of flight: [Emergency descent](https://openairdocs.org/ntsb-phases/600) (OpenAirDocs' grouping) - Defining event: [Autorotation: Controlled flight into terr/obj (CFIT)](https://openairdocs.org/ntsb-events/120) - Highest injury: Minor injuries - Injuries: 1 minor - Status: Completed, report June 9, 2015 - Report: Approved by Office Director - NTSB office: Central Region - Parties: Flight Standards District Office, Composite FX - NTSB case key (mKey): 90377 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=CEN15LA042 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/90377/pdf - NTSB docket: https://data.ntsb.gov/Docket?ProjectID=90377 - Page: https://openairdocs.org/ntsb/CEN15LA042 ## Probable cause The pilot’s failure to maintain adequate clearance from trees during a precautionary landing. Contributing to the accident was the pilot’s inadequate preflight inspection during which he failed to detect a loose drive belt, which resulted in an in-flight shudder. ## Findings NTSB's coded findings; those marked are part of the probable cause. - [Inspection: preflight inspection](https://openairdocs.org/ntsb-findings/02061510): Personnel issues › Task performance · Pilot (probable cause); cases with it: [Mosier Robert S MOSQUITO XET, 1 case](https://openairdocs.org/ntsb-findings/02061510/cases.md?model=05630GN), [All aircraft, 551 cases](https://openairdocs.org/ntsb-findings/02061510/cases.md) - [Attention/monitoring: monitoring environment](https://openairdocs.org/ntsb-findings/02021545): Personnel issues › Psychological · Pilot (probable cause); cases with it: [Mosier Robert S MOSQUITO XET, 1 case](https://openairdocs.org/ntsb-findings/02021545/cases.md?model=05630GN), [All aircraft, 809 cases](https://openairdocs.org/ntsb-findings/02021545/cases.md) - [Info processing/decision: identification/recognition](https://openairdocs.org/ntsb-findings/02041510): Personnel issues › Action/decision · Pilot (probable cause); cases with it: [Mosier Robert S MOSQUITO XET, 1 case](https://openairdocs.org/ntsb-findings/02041510/cases.md?model=05630GN), [All aircraft, 559 cases](https://openairdocs.org/ntsb-findings/02041510/cases.md) - [Performance/control parameters: altitude](https://openairdocs.org/ntsb-findings/01062012): Aircraft › Aircraft oper/perf/capability · Not attained/maintained (probable cause); cases with it: [Mosier Robert S MOSQUITO XET, 1 case](https://openairdocs.org/ntsb-findings/01062012/cases.md?model=05630GN), [All aircraft, 1,310 cases](https://openairdocs.org/ntsb-findings/01062012/cases.md) - [Object/animal/substance: tree(s)](https://openairdocs.org/ntsb-findings/03022020): Environmental issues › Physical environment · Awareness of condition (probable cause); cases with it: [Mosier Robert S MOSQUITO XET, 1 case](https://openairdocs.org/ntsb-findings/03022020/cases.md?model=05630GN), [All aircraft, 933 cases](https://openairdocs.org/ntsb-findings/03022020/cases.md) ## Sequence of events The events NTSB coded, in order, by phase of flight. The defining event best describes what happened. - [Initial climb: Powerplant sys/comp malf/fail](https://openairdocs.org/ntsb-events/340); cases with it: [Mosier Robert S MOSQUITO XET, 1 case](https://openairdocs.org/ntsb-events/340/sequence.md?model=05630GN), [All aircraft, 820 cases](https://openairdocs.org/ntsb-events/340/sequence.md) - [Autorotation: Controlled flight into terr/obj (CFIT)](https://openairdocs.org/ntsb-events/120) (defining event); cases with it: [Mosier Robert S MOSQUITO XET, 1 case](https://openairdocs.org/ntsb-events/120/sequence.md?model=05630GN), [All aircraft, 1,074 cases](https://openairdocs.org/ntsb-events/120/sequence.md) ## Analysis The pilot reported that he noticed the helicopter abruptly shudder during the crosswind turn. The pilot lowered the collective control, entered an autorotation, and turned back toward the airport. As he approached the runway area, the helicopter skids passed over a row of trees by about 5 or 10 ft. Immediately after the skids cleared the trees, the pilot began a cyclic flare, which resulted in the tail rotor striking a tree and a subsequent loss of directional control. Examination of the helicopter revealed that the belt for the secondary drive reduction unit was loose, which allowed the belt to jump the drive cogs on the pulley. The belt was loose due to excessive wear of the pulley, which resulted in an abrupt in-flight shudder. The helicopter operating manual preflight inspection includes a check for proper belt tension. ## Factual narrative On November 8, 2014, about 1000 central standard time, a Composite FX Mosquito XET helicopter, N922RM, impacted trees during approach for landing at the Bailes Airport (7R9), Angleton, Texas. The pilot sustained minor injuries and 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. Day visual meteorological conditions prevailed for the local flight, which departed without a flight plan. According to the pilot, he noticed the helicopter abruptly shudder during the crosswind turn at about 300 feet above ground level. The pilot lowered the collective control, entered an autorotation, and turned back toward the airport. As he approached the runway area, the helicopter skids passed over a row of trees by about 5 or 10 feet. Immediately after the skids cleared these trees, the pilot began a cyclic flare, which resulted in the tail rotor striking a tree. The helicopter began to spin violently and impacted the ground several times, damaging the main rotor and tail boom. The helicopter was examined by Federal Aviation Administration and Composite FX personnel at the kit manufacturer's facility. The belt for the secondary drive reduction unit was observed to be loose, which allowed the teeth of the drive belt to "jump" the drive cogs on the pulley. The loose belt was due to excessive wear on the pulley. The operating manual pre-flight inspection includes a check for tension of this belt, during which the operator should attempt to deflect the belt by about 3/16 of an inch, with an estimated five pounds of finger pressure in the middle of a long, unsupported span of the belt. ## Aircraft - Registration: [N922RM](https://openairdocs.org/deregistered/N922RM-2018-04-18), registration cancelled 2018-04-18, S/N MXE 1099109B, built 2011 (OpenAirDocs) - Reported make and model: MOSIER ROBERT S MOSQUITO XET (NO SERIES) - Registry model: [Mosier Robert S MOSQUITO XET](https://openairdocs.org/model/mosier-robert-s-mosquito-xet) (registry code 05630GN) (OpenAirDocs) - Registry engine: [Amateur-built UNKNOWN ENG](https://openairdocs.org/engine/amateur-built-unknown-eng) (registry code 99999) (OpenAirDocs) - Category: Helicopter, amateur-built - Serial number: MXE 1099109B - Year built: 2011 - Airframe hours: 123.6 - Engines: Solar T-62T-2A1 95 horsepower turbo jet - Damage: Substantial damage - Flight: Personal, Part 91 - Operator: Charles Burgoon - Registered owner: Charles Burgoon - Airworthiness certificate: Special, Experimental (Special) - Last inspection: Condition, May 5, 2014 - Departed: 7R9, Angleton, TX - Destination: 7R9, Angleton, TX - Airport: 7R9, Bailes Airport ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 59; injuries: minor; flight instructor, private, commercial, sport pilot, airline transport; airplane ratings: multi-engine land, single-engine land; instrument ratings: airplane; medical: class 3, with waivers/limitations; last flight review April 16, 2014; seat: single; restraint: 3-point; flight hours: 1,800 total, 12 in this make and model ## Weather - Conditions: Visual (VMC), Day - Wind: 70° at 5 knots - Visibility: 10 statute miles - Lowest ceiling: 10,000 ft overcast - Temperature: 61 °F, dew point 46 °F - Altimeter: 30.11 inHg - Observed at: KLBX, 5 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 20141108020009A](https://openairdocs.org/incident/20141108020009A), Nov 8, 2014: Mosier Robert S MOSQUITO XET, Angleton, TX, Destroyed. The pilot was in a climb on the crosswind pattern and encountered a shudder in the aircraft. The pilot stated he immediataely entered an autorotation with… ## Docket (1 files) The files NTSB released with the investigation on April 27, 2015, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=90377. 994 KB in all. - Pilot/Operator Aircraft Accident Report, NTSB Form 6120.1 (item 1, .PDF, 994 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40425637&FileExtension=.PDF&FileName=Pilot%2FOperator%20Aircraft%20Accident%20Report,%20NTSB%20Form%206120.1-Redacted.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.