# NTSB NYC00LA022: Godbout Exec 162F, N228CH, Milan, NH, October 30, 1999 - Type: NTSB accident investigation - Classification: Accident · Fatal · Limited investigation · Final report - Date: October 30, 1999, 15:30 local (19:30 UTC) - Place: Milan, NH - Location: 44.5734° N, 71.1851° W: Placed by OpenAirDocs: center of Milan, NH, within about 6 miles (OpenAirDocs) - Nearby events: https://openairdocs.org/map.md?lat=44.5734&lon=-71.1851&mi=10 - Phase of flight: [Maneuvering](https://openairdocs.org/ntsb-phases/450) (OpenAirDocs' grouping) - Highest injury: Fatal - Injuries: 1 fatal - Status: Completed, report May 17, 2001 - Report: Approved by Office Director - NTSB case key (mKey): 47693 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=NYC00LA022 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/47693/pdf - Page: https://openairdocs.org/ntsb/NYC00LA022 ## Probable cause The pilot's failure to maintain proper rotor rpm while maneuvering, which resulted in main rotor blade flapping, and its subsequent impact with the tail boom. A factor was the pilot's lack of experience in maneuvering flight. ## Sequence of events In NTSB's coding before 2008 (https://www.ntsb.gov/GILS/Documents/codman.pdf). - Loss of control - in flight, maneuvering - rotor rpm - not maintained, pilot in command (cause) - rotor system,main rotor blade - other - lack of total experience in type operation, pilot in command (contributing factor) - In flight collision with object, descent - uncontrolled ## Analysis After transiting to an area about 8 miles from its departure point, the homebuilt helicopter was observed making a low pass along a 5-mile trail. It then flew to a point about midway along the trail, where trail maintenance was taking place, and began maneuvering about 50 feet, over 50-foot trees. It entered a steep turn, there was a loud 'bang', and the helicopter descended almost vertically into the woods. The main wreckage was found upside down, and the tail boom was located about 150 feet away. There were paint transfer marks where the tail boom had separated, which matched the paint on the end of a main rotor blade. That blade exhibited downward bending near its inboard end, and upward bending near its outboard end. The blade's leading edge had impact marks and paint transfer marks from the tail boom. There was no evidence of in-flight blade failure or separation. Fuel was found onboard the helicopter, and the engine exhibited scoring marks consistent with a sudden stoppage. The student pilot had 64 hours of flight time, and had been to the kit manufacturer's facility three times for training. He had been endorsed for hovering flight, flight through translational lift and quickstops, provided he remained within 35 feet of the ground at all times. He had previously had an accident while hovering the helicopter. Another builder/pilot, who had flown with the student pilot, stated that his 'ability to maintain proper rotor rpm was a problem.' An onboard recording of throttle positions revealed that the throttle had been opened to 29 to 32 percent, for the first 4, of the last 5 minutes of flight, consistent with the helicopter transiting the area. From 56 seconds, until 6 seconds prior to the last recording, the throttle position was approximately 38 to 40 percent, consistent with the use of added power for maneuvering over the trees. Three seconds before the last recording, the throttle had been closed to 7 percent, before it was returned to 38 percent for the last two seconds of the recording. ## Factual narrative HISTORY OF FLIGHT On October 30, 1999, about 1530 Eastern Daylight Time, a homebuilt Exec 162F, N228CH, was destroyed while maneuvering near Milan, New Hampshire. The certificated student pilot/builder was fatally injured. No flight plan had been filed for the local flight, which originated from the student pilot's back yard in Berlin, New Hampshire. The personal flight was conducted under 14 CFR Part 91. According to a Federal Aviation Administration (FAA) inspector, the pilot flew about 8 miles west northwest from his home, to a wooded area where his son and a crew were working on a snowmobile trail. A witness, on top of a mountain about 9/10 of a mile from the accident site, observed the helicopter making a low pass, from south to north, along the 5-mile trail. The pilot then flew the helicopter over an area midway up the trail, where a bridge was being constructed over a brook. The helicopter began circling and maneuvering, approximately 50 feet above 30- to 50-foot trees, west of the trail. The witness saw the helicopter go into a very steep right bank, and "tumble" into the trees. He also heard a loud "snap or bang," followed by "a brief pause," before he heard the helicopter impact the trees. Another witness, on the ground at the worksite, whose view was partially obscured by vegetation, said the helicopter was in a left bank just before the accident. He, and other witnesses at the site reported hearing the engine "rev-up" just before impact with the trees. PERSONNEL INFORMATION The pilot held a student pilot certificate, and his third class medical certificate was dated May 21, 1998. The pilot's student pilot certificate had two endorsements, one on August 6, 1999, and one on September 10, 1999. Corresponding logbook endorsements included: On August 6, 1999: "I certify that [the student pilot] has been "instructed in the flight operations of FAR 61.87 (A)(B)(C)(F 1,2,10,11,13) and found competent for solo hover in his/her assigned test area, in no more than five mph winds. Maneuvers to include hover taxi, hovering turns and patterns in ground-effect below translation in the Rotorway Exec/Exec 90. Day VFR only. Also valid for Exec 162F." On September 10, 1999: "I certify that [the student pilot] has been "instructed in the flight operations of FAR 61.87 (A)(B)(C)(F 1,2,10,11,13,16), but only competent in no more than five mph winds. All hovering maneuvers are to be in ground effect. Translational flight is approved to a maximum height of 35 feet AGL while avoiding operation in the shaded area of the height-velocity envelope for the Exec/Exec 90. Also valid for Exec 162F." The pilot's logbook indicated he had 64.8 hours of flight time as of October 21, 1999. All of that flight time had been in Rotorway Exec helicopters. On April 17, 1999, with 12.7 hours of flight time, the pilot had a "rollover incident" while attempting to hover his helicopter. The pilot's formal flight training had been conducted at Rotorway International, where he had completed the first phase and portions of the second phase of a three-phase instructional program. According to the chief pilot of Rotorway: "[The student pilot's] first visit to us was the week of 8 March 1999. He received 10.0 hours of flight instruction, administered by myself and...another flight instructor. At the end of that week, I did not feel sufficiently confident in [the student pilot's] ability to hover and land the helicopter to issue an endorsement.... Sometime between his first and second visit, he attempted to hover his own helicopter, and rolled it over, doing damage to the blades and requiring substantial repair work. On his second visit, the week of 2 August 1999, [the student pilot] received 11.7 hours of additional instruction, and on 6 August 1999 I issued an endorsement allowing him to hover in his assigned training area, in no more than 5 mph winds, providing that his altitude not exceed the ground effect altitude. His third visit was on the week of 7 September 1999. This was to be the week that [the student pilot] learned the 'altitude maneuvers' i.e., quick stops, takeoff and landing, traffic pattern, steep approach and maximum power takeoff, and emergency procedures. At the end of the week, I did not feel sufficiently confident in [the student pilot's] abilities to issue the usual endorsement, and so I did not issue the usual endorsement. I did issue an endorsement allowing him to perform one of the trained maneuvers: the quick stop. The endorsement limited [the student pilot] to practice hovering and flight through effective translational lift, providing that he remain within 35 feet of the ground at all times, and not attempt to fly in a manner which would enter the danger areas of the height-velocity envelope for the 162F helicopter. He was not to attempt to fly the helicopter at all in more than 5-mph winds." The FAA inspector conducted an interview with a Rotorway Exec 162F pilot/builder, who had frequently helped other Rotorway builders, and who had approximately 500 hours in Rotorway helicopters. According to the inspector, in September 1999, the other pilot/builder assisted the student pilot in balancing his main and tail rotor blades. He also flew with the student pilot, and noted that his "ability to hover had improved, but his ability to maintain proper rotor rpm was a problem." WRECKAGE AND IMPACT INFORMATION All major components were accounted for at the accident scene. According to the FAA Inspector: "There was no evidence of any fire. The tree damage was limited to the tops of two trees, which were broken off, and two other trees were knocked down. The tree damage indicated the helicopter descended through the...trees in an almost vertical path. The main portion of the helicopter came to rest inverted on its back and resting on the main rotor head with the nose elevated and the tail down...Both main rotor blades were still attached, but damaged, (after-market composite blades, trailing edge separated.) The tail boom had been severed approximately 4 feet from the aft end. The severed portion of the tail boom and the entire tail rotor were found approximately 150 feet from the main wreckage. The tail rotor showed no evidence of rotational...chordwise scoring. There was clear paint transfer and impact damage on the tail boom to match the main rotor blades." The wreckage was subsequently moved to a garage, where a detailed inspection was performed. During the recovery, 5 gallons of fuel were drained, although additional fuel remained in the tanks. According to the FAA inspector: "The cyclic controls were verified to be intact from the stick to the rotorhead and moved throughout the entire range. The collective controls were verified to be connected and relatively intact. The right collective handle was broken off. The left collective handle was intact and moved through its normal range. The vertical push-pull collective actuating rod behind the left seat was bent and somewhat crushed on impact, but still moved through its normal range. The tail rotor control cable was severed, but both ends were...connected. The tail rotor actuator mechanism moved freely throughout its normal range. The main fuel selector T-handle was down (on) and the remote valve was verified to be in the "on" position. The four shear bolts for the main rotor drive at the large secondary cog belt drive pulley were all separated. The four primary "V" drive belts and the secondary drive cog belt were intact. Both main rotor blade droop stops (teeter stop straps) were bent up on the rotor head. Both main rotor blades were composite after-market parts...No serial numbers were found on the blades, but each blade tip had been previously marked during the tracking process; one with red ink and the other with black ink. The black blade was...broken at mid-span and be ## Aircraft - Registration: [N228CH](https://openairdocs.org/deregistered/N228CH-2001-09-18), registration cancelled 2001-09-18, S/N 6318 (OpenAirDocs) - Reported make and model: Godbout EXEC 162F - Registry model: [Godbout Roger J EXEC 162F](https://openairdocs.org/model/godbout-roger-j-exec-162f) (registry code 05606CD) (OpenAirDocs) - Category: Helicopter, amateur-built - Serial number: 6318 - Airframe hours: 51 - Engines: Rotorway RI 162F 150 horsepower reciprocating - Damage: Destroyed - Flight: Personal, Part 91 - Registered owner: Roger Godbout - Airworthiness certificate: Special, Experimental (Special) - Departed: NONE, BERLIN, NH ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 50; student; medical: class 3, valid medical--no waivers/lim.; seat: left; flight hours: 65 total, 52 in the last 90 days ## Weather - Conditions: Visual (VMC), Day - Wind: 190° at 7 knots - Visibility: 10 statute miles - Lowest ceiling: none - Temperature: 54 °F, dew point 36 °F - Altimeter: 30.00 inHg - Observed at: BML, 8 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 19991030045679A](https://openairdocs.org/incident/19991030045679A), Oct 30, 1999: Amtr EXEC162F, Milan, NH, Destroyed. (.4)After transiting to an area about 8 miles from its departure point, the homebuilt helicopter was observed making a low pass along a 5-mile trail. It then… 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.