# NTSB DEN04CA143: Robinson R22 Beta 2, N7533E, Spanish Fork, UT, September 16, 2004 - Type: NTSB accident investigation - Classification: Accident · Minor injuries · Data collection · Final report - Date: September 16, 2004, 16:20 local (22:20 UTC) - Place: Spanish Fork, UT - Coordinates: 40.141387, -111.661109 - Nearby events: https://openairdocs.org/map.md?lat=40.1414&lon=-111.6611&mi=10 - Phase of flight: [Landing](https://openairdocs.org/ntsb-phases/550) (OpenAirDocs' grouping) - Highest injury: Minor injuries - Injuries: 1 minor, 1 uninjured - Status: Completed, report March 30, 2005 - Report: Approved by Office Director - Parties: FAA Flight Standards District Office - NTSB case key (mKey): 60160 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=DEN04CA143 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/60160/pdf - Page: https://openairdocs.org/ntsb/DEN04CA143 ## Probable cause the pilot's failure to maintain adequate rotor rpm during a practice autorotation, and the flight instructor's improper flare. A contributing factor was the instructor's inadequate supervision of the pilot. ## Sequence of events In NTSB's coding before 2008 (https://www.ntsb.gov/GILS/Documents/codman.pdf). - Hard landing, landing - emergency procedure - simulated (cause) - adequate rotor rpm - not maintained, pilot in command (cause) - flare - improper, pilot in command(cfi) (cause) - supervision - inadequate, pilot in command(cfi) (contributing factor) ## Analysis The flight instructor was preparing the commercial pilot for his upcoming flight instructor practical test. He asked the pilot to demonstrate a simulated engine failure with autorotation to landing. The pilot rolled off the power and entered an autorotation. Airspeed was between 65 and 70 knots, and rpm was maintained between 98 and 100 percent. The rate of descent was 2,000 feet per minute (fpm) in the 180-degree turn, but decreased to 1,800 fpm when they lined up with the runway. Rpm was at 97 percent and started to drop. The warning horn and light activated at 100 feet agl. Rpm was at 94 percent. The instructor took control of the helicopter and applied full power and "a small cyclic flare, and lowered the collective slightly to recover rpm." The helicopter began to shake with a low frequency vibration. Rpm was between 92 and 94 percent. Approximately 50 feet agl, the instructor applied "a strong cyclic flare" to reduce the rate of descent. The vibrations continued and the helicopter continued to settle. Just before ground contact, the instructor noted the rpm needles were "married at 92 percent (sic)." The helicopter contacted the runway tail first, then the rear portion of the skids hit. The helicopter bounced and began to spin. The helicopter came to rest right side up and the engine continued to run. ## Factual narrative On September 16, 2004, approximately 1620 mountain daylight time, a Robinson R22, N7533E, piloted by a commercial pilot, sustained substantial damage when it made a hard landing during a simulated power loss and practice autorotation at the Spanish Fork-Springvale Municipal Airport (U77), Spanish Fork, Utah. Visual meteorological conditions prevailed at the time of the accident. The local instructional flight was being conducted under the provisions of Title 14 CFR Part 91 without a flight plan. The pilot received minor injuries and flight instructor was not injured. The flight originated at Provo (PVU), Utah, approximately 1600. According to the flight instructor's written statement and telephone interview, he was preparing the commercial pilot for his upcoming flight instructor practical test. He asked the pilot to demonstrate a simulated engine failure with autorotation to landing. The pilot rolled off power and entered an autorotation. Airspeed was between 65 and 70 knots, and rpm was maintained between 98 and 100 percent. The rate of descent was 2,000 feet per minute (fpm) in the 180-degree turn, but decreased to 1,800 fpm when they lined up with the runway. Rpm was at 97 percent and started to drop. The warning horn and light activated at 100 feet agl. Rpm was at 94 percent. The instructor took control of the helicopter and applied full power and "a small cyclic flare, and lowered the collective slightly to recover rpm." The helicopter began to shake with a low frequency vibration. Rpm was between 92 and 94 percent. Approximately 50 feet agl, the instructor applied "a strong cyclic flare" to reduce the rate of descent. The vibrations continued and the helicopter continued to settle. Just before ground contact, the instructor noted the rpm needles were "married at 92 percent (sic)." The helicopter contacted the runway tail first, then the rear portion of the skids hit. The helicopter bounced and began to spin. The helicopter came to rest right side up and the engine continued to run. The following is an excerpt from Section 4, "Normal Procedures," of the Robinson R22 PILOT'S OPERATING HANDBOOK, p. 4-10: "CAUTION. The R22 has a light, low-inertia rotor system. Most of the energy required for an autorotation is stored in the forward momentum of the aircraft, not in the rotor. Therefore, a well timed cyclic flare is required and rotor RPM must be kept in the green until just before ground contact. "CAUTION. During simulated engine failures, a rapid decrease in rotor RPM will occur, requiring immediate lowering of collective control to avoid dangerously low rotor RPM. Catastrophic rotor stall could occur if the RPM ever drops below 80 percent plus 1 percent per 1000 feet of altitude." ## Aircraft - Registration: [N7533E](https://openairdocs.org/deregistered/N7533E-2014-09-16), registration cancelled 2014-09-16, S/N 3646, built 2004 (OpenAirDocs) - Reported make and model: Robinson R22 Beta 2 - 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: 3646 - Airframe hours: 295 - Engines: Lycoming O-360-J2A 131 horsepower reciprocating - Damage: Substantial damage - Flight: Instructional, Part 91 - Operator: Silver State Helicopters - Registered owner: Eric Spitzer - Airworthiness certificate: Standard, Normal - Last inspection: 100 hour, September 6, 2004, 47 hours before - Departed: PVU, Provo, UT - Destination: PVU - Airport: U77, Spanish Fork-Springville, runway 30, 5,700 × 100 ft, asphalt ## Flight crew As NTSB recorded them. NTSB leaves out names. - Flight instructor; age 31; injuries: none; flight instructor, commercial; medical: class 2, valid medical--no waivers/lim.; last flight review August 5, 2003; seat: right; flight hours: 1,040 total, 920 in this make and model, 975 as pilot in command, 185 in the last 90 days, 33 in the last 30 days, 2 in the last 24 hours - Pilot; age 21; injuries: minor; commercial; airplane ratings: single-engine land; medical: class 2, valid medical--w/ waivers/lim; last flight review June 16, 2004; seat: left; flight hours: 268 total, 185 in this make and model, 176 as pilot in command, 29 in the last 90 days, 9 in the last 30 days, 1 in the last 24 hours ## Weather - Conditions: Visual (VMC), Day - Wind: 210° at 4 knots - Visibility: 10 statute miles - Lowest ceiling: none - Temperature: 82 °F, dew point 32 °F - Altimeter: 29.92 inHg - Observed at: PVU, 7 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 20040916021869A](https://openairdocs.org/incident/20040916021869A), Sep 16, 2004: Robsin R22BETA, Spanish Fork, UT, Substantial damage. (-23) On 09/16/04 at 1610 a Robinson R-22 (beta), N7533E, s/n 3646, impacted the ground during flight instruction, 180 degree turn autorotation, at Spanish… 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.