# NTSB ERA10TA429: Bell UH1H, Warrenton, VA, August 16, 2010 - Type: NTSB accident investigation - Classification: Accident · No injuries · Final report - Date: August 16, 2010, 14:45 local (18:45 UTC) - Place: Warrenton, VA - Coordinates: 38.586387, -77.710556 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=38.5864&lon=-77.7106&mi=10 - Phase of flight: [Landing](https://openairdocs.org/ntsb-phases/550) (OpenAirDocs' grouping) - Defining event: [Landing-flare/touchdown: Abrupt maneuver](https://openairdocs.org/ntsb-events/270) - Highest injury: No injuries - Injuries: 2 uninjured - Status: Completed, report April 7, 2011 - Report: Approved by Office Director - NTSB office: Eastern Region Aviation - Parties: FAA/FSDO - NTSB case key (mKey): 76990 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=ERA10TA429 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/76990/pdf - NTSB docket: https://data.ntsb.gov/Docket?ProjectID=76990 - Page: https://openairdocs.org/ntsb/ERA10TA429 ## Probable cause The pilot receiving instruction's failure to maintain a proper pitch attitude during the practice autorotation maneuver. ## Findings NTSB's coded findings; those marked are part of the probable cause. - [Action: incorrect action performance](https://openairdocs.org/ntsb-findings/02041015): Personnel issues › Action/decision · Pilot (probable cause); cases with it: [All aircraft, 1,386 cases](https://openairdocs.org/ntsb-findings/02041015/cases.md) - [Performance/control parameters: landing flare](https://openairdocs.org/ntsb-findings/01062041): Aircraft › Aircraft oper/perf/capability · Incorrect use/operation (probable cause); cases with it: [All aircraft, 1,285 cases](https://openairdocs.org/ntsb-findings/01062041/cases.md) ## Sequence of events The events NTSB coded, in order, by phase of flight. The defining event best describes what happened. - [Landing-flare/touchdown: Abrupt maneuver](https://openairdocs.org/ntsb-events/270) (defining event); cases with it: [All aircraft, 346 cases](https://openairdocs.org/ntsb-events/270/sequence.md) - [Landing-flare/touchdown: Tailstrike](https://openairdocs.org/ntsb-events/091); cases with it: [All aircraft, 124 cases](https://openairdocs.org/ntsb-events/091/sequence.md) - [Landing-flare/touchdown: Part(s) separation from AC](https://openairdocs.org/ntsb-events/338); cases with it: [All aircraft, 563 cases](https://openairdocs.org/ntsb-events/338/sequence.md) - [Landing-flare/touchdown: Loss of control on ground](https://openairdocs.org/ntsb-events/230); cases with it: [All aircraft, 4,585 cases](https://openairdocs.org/ntsb-events/230/sequence.md) ## Analysis The pilot receiving instruction was performing a practice autorotation from about 1,800 feet above ground level. During the touchdown, the pitch of the helicopter increased excessively and the tail rotor and stinger contacted the runway. The certificated flight instructor took authority of the helicopter's controls and lowered the pitch to arrest the tail-low condition. The helicopter began to shudder and both pilots manipulated the flight controls in an attempt to maintain aircraft control. The helicopter then struck the runway in a left-skid-low attitude. A postaccident examination of the wreckage revealed that the tail rotor was separated and the vertical stabilizer was severed. The pilots reported no mechanical anomalies with the helicopter during the autorotation. ## Factual narrative On August 16, 2010, about 1445 eastern daylight time, a Bell UH1H helicopter, U.S. Customs tail number 21769, and no Federal Aviation Administration registration number, was substantially damaged during a practice autorotation at Warrenton-Fauquier Airport (HWY), Warrenton, Virginia. The helicopter was operated by U.S. Customs and Border Protection. The certificated commercial pilot and flight instructor were not injured. Visual meteorological conditions prevailed at the time, and a visual flight rules flight plan was filed for the public use training flight. The flight originated at Manassas, Virginia (HEF) at 1400. The pilot receiving instruction reported that he was attempting a practice autorotation to runway 33 from 1,800 feet. During the touchdown, the pitch of the helicopter increased and the tail rotor and stinger contacted the runway. The flight instructor immediately pitched the helicopter forward to arrest the tail-low condition when the helicopter began to shudder. Both pilots worked to maintain aircraft control and the helicopter pivoted to the right due to the loss of tail rotor control. The helicopter struck the runway in a left-skid-low condition and came to rest near the taxiway exiting runway 33. The pilots reported that there were no mechanical anomalies with the helicopter during the autorotation. The pilot receiving instruction reported about 3,500 hours of helicopter flight time, including 100 hours in the UH1H. He also reported 20 hours in the 90 days prior to the accident and 10 hours in the 30 days prior to the accident. A cursory examination of the wreckage revealed the tail rotor was separated and the vertical stabilizer was severed. The 1440 weather observation for HWY included the following: scattered clouds at 3,700 feet, ceiling broken at 4,400 feet, surface winds from 230 degrees at 6 knots, 10 statute miles visibility, temperature 35 degrees Celsius, dew point 22 degrees Celsius, and an altimeter setting of 29.94 inches of mercury. ## Aircraft - Registration: UNREG (not matched to a registry record) - Reported make and model: BELL UH1H - Category: Helicopter - Serial number: 73-21769 - Airframe hours: 5140 - Engines: Honeywell T53-L-703 1800 horsepower turbo shaft - Damage: Substantial damage - Flight: Public aircraft - federal, Public use - Operator: U.S. Customs and Border Protection - Registered owner: U.S. Customs and Border Protection - Airworthiness certificate: Unknown - Last inspection: Continuous airworthiness, August 13, 2010 - Departed: HEF, Manassas, VA - Destination: HWY, Warrenton, VA - Flight plan: Company VFR - Airport: HWY, Warrenton-Fauquier Airport, runway 33, 5,000 × 100 ft, asphalt ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 44; injuries: none; commercial; airplane ratings: single-engine land; instrument ratings: helicopter; medical: class 1, without waivers/limitations; last flight review November 16, 2009; seat: right; flight hours: 4,300 total, 100 in this make and model, 4,000 as pilot in command, 20 in the last 90 days, 10 in the last 30 days, 1 in the last 24 hours - Flight instructor; age 37; injuries: none; flight instructor, airline transport; airplane ratings: single-engine sea, single-engine land, multi-engine land; instrument ratings: helicopter, airplane; medical: class 2, with waivers/limitations; last flight review June 24, 2010; seat: left; flight hours: 9,500 total, 105 in this make and model, 8,000 as pilot in command, 88 in the last 90 days, 49 in the last 30 days, 1 in the last 24 hours ## Weather - Conditions: Visual (VMC), Day - Wind: 230° at 6 knots - Visibility: 10 statute miles - Lowest ceiling: 4,400 ft broken - Temperature: 95 °F, dew point 72 °F - Altimeter: 29.94 inHg - Observed at: HWY ## Docket (4 files) The files NTSB released with the investigation on December 3, 2010, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=76990. 2.4 MB in all. - Statement from Flight Crewmembers (item 1, .PDF, 9 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40339576&FileExtension=.PDF&FileName=Statement%20from%20Flight%20Crewmembers-Redacted.PDF - Weather Reports for HWY (item 2, .PDF, 39 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40339577&FileExtension=.PDF&FileName=Weather%20Reports%20for%20HWY-Master.PDF - Photo 1: Wreckage Viewed from Left Side (US Customs and Border Protection Digital Photo) (item 3, .PDF, 1.2 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40339047&FileExtension=.PDF&FileName=Photo%201%3A%20Wreckage%20Viewed%20from%20Left%20Side%20(US%20Customs%20and%20Border%20Protection%20Digital%20Photo)-Master.PDF - Photo 2: Wreckage Viewed from Right Side (US Customs and Border Protection Digital Photo) (item 4, .PDF, 1.1 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40339048&FileExtension=.PDF&FileName=Photo%202%3A%20Wreckage%20Viewed%20from%20Right%20Side%20(US%20Customs%20and%20Border%20Protection%20Digital%20Photo)-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.