# NTSB DFW07CA096: Robinson R-22 Beta, N7534S, Spring, TX, April 25, 2007 - Type: NTSB accident investigation - Classification: Accident · No injuries · Data collection · Final report - Date: April 25, 2007, 15:34 local (20:34 UTC) - Place: Spring, TX - Coordinates: 30.061944, -95.55278 - Nearby events: https://openairdocs.org/map.md?lat=30.0619&lon=-95.5528&mi=10 - Phase of flight: [Takeoff](https://openairdocs.org/ntsb-phases/300) (OpenAirDocs' grouping) - Highest injury: No injuries - Injuries: 2 uninjured - Status: Completed, report March 31, 2008 - Report: Approved by Office Director - Parties: Houston, Texas - NTSB case key (mKey): 65640 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=DFW07CA096 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/65640/pdf - Page: https://openairdocs.org/ntsb/DFW07CA096 ## Probable cause The student pilot's improper use of the flight controls resulting in dynamic rollover. Contributing factors were the delayed remedial action by the flight instructor and the uneven, muddy terrain conditions. ## Sequence of events In NTSB's coding before 2008 (https://www.ntsb.gov/GILS/Documents/codman.pdf). - Roll over, takeoff - dynamic rollover - encountered, dual student (cause) - rotorcraft flight controls - improper use of, dual student (cause) - remedial action - delayed, pilot in command(cfi) (contributing factor) - In flight collision with terrain/water, takeoff - terrain condition - rough/uneven (contributing factor) - terrain condition - muddy (contributing factor) ## Analysis The helicopter experienced dynamic rollover and came to rest on its left side while attempting to take off. The flight instructor reported in the NTSB Form 6120.1 (Pilot/Operator Aircraft Accident/Incident Report) that the instructional flight comprised of practice autorotations and rapid decelerations or quick-stops. The practice area where these maneuvers were performed was reported by the flight instructor as "a grassy, dirt area with occasional dirt mounds raising approximately 1 and 1/2 feet above the ground". The ground was also wet and muddy due to thunderstorms having passed through the area prior to the flight. While executing the third quick-stop maneuver, the student pilot receiving instruction performed a normal takeoff from a 3-foot hover. The helicopter assumed a pronounced nose low attitude while accelerating during takeoff and the toe of the right landing gear skid simultaneously contacted a dirt mound. The student attempted to correct the right yawing condition by over-controlling to the left, while the flight instructor compensated by raising the collective and applying right cyclic. The flight instructor concluded that "by the time the inputs were felt the helicopter had reached its critical angle and rolled [to the] left side." The helicopter sustained structural damage to the main rotor, fuselage, tail boom, and tail rotor. The flight instructor and student pilot were able to exit the helicopter unassisted and neither was injured. At the time of the accident the flight instructor reported having accumulated 116 hours as a flight instructor and the student had accumulated a total of 24 hours in helicopters. The weather at the accident site was reported as calm winds, 10 miles visibility, a broken ceiling at 2,100 feet, and a temperature of 26 degrees Celsius. ## Factual narrative The helicopter experienced dynamic rollover and came to rest on its left side while attempting to take off. The 423-hour helicopter flight instructor reported in the NTSB Form 6120.1 (Pilot/Operator Aircraft Accident/Incident Report) that the instructional flight comprised of practice autorotations and rapid decelerations or quick-stops. The practice area where these maneuvers were performed was reported by the flight instructor as "a grassy, dirt area with occasional dirt mounds raising approximately 1 and 1/2 feet above the ground." The ground was also wet and muddy due to thunderstorms having passed through the area prior to the flight. While executing the third quick-stop maneuver, the student pilot receiving instruction performed a normal take off from a 3-foot hover. The helicopter assumed a pronounced nose low attitude while accelerating during takeoff and the toe of the right landing gear skid simultaneously contacted a dirt mound. The student attempted to correct the right yawing condition by over-controlling to the left, while the flight instructor compensated by raising the collective and applying right cyclic. The flight instructor concluded that "by the time the inputs were felt the helicopter had reached its critical angle and rolled [to the] left side." The helicopter sustained structural damage to the main rotor, fuselage, tail boom, and tail rotor. The flight instructor and student pilot were able to exit the helicopter unassisted and neither was injured. At the time of the accident the flight instructor reported having accumulated 116 hours as a flight instructor and the student had accumulated a total of 24 hours in helicopters. The weather at the accident site was reported as calm winds, 10 miles visibility, a broken ceiling at 2,100 feet AGL, and a temperature of 26 degrees Celsius. ## Aircraft - Registration: [N7534S](https://openairdocs.org/deregistered/N7534S-2007-07-23), registration cancelled 2007-07-23, S/N 3657, built 2004 (OpenAirDocs) - Reported make and model: Robinson R-22 Beta - Registry model: [Robinson Helicopter R22 BETA](https://openairdocs.org/model/robinson-helicopter-r22-beta) (registry code 7640110) (OpenAirDocs) - Registry engine: [Lycoming O-360 series](https://openairdocs.org/engine/lycoming-o-360-series) (registry code 41575, reciprocating) (OpenAirDocs) - Category: Helicopter - Serial number: 3657 - Airframe hours: 1329 - Engines: Lycoming O-360 180 horsepower reciprocating - Damage: Substantial damage - Flight: Instructional, Part 91 - Operator: David Vargas - Registered owner: Helicopter Services Inc. - Airworthiness certificate: Standard, Normal - Last inspection: 100 hour, April 1, 2007 - Departed: KDWH, Spring, TX - Destination: KDWH - Airport: KDWH, David Wayne Hooks, runway 17R, 7,009 × 100 ft, grass/turf ## Flight crew As NTSB recorded them. NTSB leaves out names. - Flight instructor; age 28; injuries: none; flight instructor, commercial; instrument ratings: helicopter; medical: class 2, without waivers/limitations; last flight review December 1, 2006; seat: left; flight hours: 423 total, 423 in this make and model, 312 as pilot in command, 116 in the last 90 days, 66 in the last 30 days, 5 in the last 24 hours - Student pilot; age 41; injuries: none; private; airplane ratings: single-engine land; medical: class 3, without waivers/limitations; last flight review May 1, 2005; seat: right; flight hours: 151 total, 24 in this make and model, 52 as pilot in command, 24 in the last 90 days, 13 in the last 30 days, 0 in the last 24 hours ## Weather - Conditions: Visual (VMC), Day - Wind: calm - Visibility: 10 statute miles - Lowest ceiling: 2,100 ft broken - Temperature: 79 °F, dew point 66 °F - Altimeter: 29.79 inHg - Observed at: KDWH 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.