# NTSB LAX98LA271: Clark Barnett J4B2, N694, Marysville, CA, August 18, 1998 - Type: NTSB accident investigation - Classification: Accident · Minor injuries · Limited investigation · Final report - Date: August 18, 1998, 12:08 local (19:08 UTC) - Place: Marysville, CA - Coordinates: 39.149932, -121.469024 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=39.1499&lon=-121.4690&mi=10 - Phase of flight: [Initial climb](https://openairdocs.org/ntsb-phases/350) (OpenAirDocs' grouping) - Highest injury: Minor injuries - Injuries: 1 minor - Status: Completed, report April 20, 2000 - Report: Approved by Office Director - NTSB case key (mKey): 43690 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=LAX98LA271 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/43690/pdf - Page: https://openairdocs.org/ntsb/LAX98LA271 ## Probable cause The pilot's inadequate rigging of the rotor blades and rudder, which led to an inability to maintain control of the gryocopter. The pilot's inadequate landing flare in soft terrain, which resulted in a nose low touchdown and subsequent nose over, and, his limited experience in gyroplanes were factors. ## Sequence of events In NTSB's coding before 2008 (https://www.ntsb.gov/GILS/Documents/codman.pdf). - Loss of control - in flight, takeoff - initial climb - flt control syst,rudder control - malfunction - maintenance,adjustment - improper, owner/pilot mechanic (cause) - rotor system,main rotor blade - malfunction - maintenance,installation - improper, owner/pilot mechanic (cause) - Forced landing, emergency landing after takeoff - Nose over, landing - flare/touchdown - terrain condition - soft (contributing factor) - flare - inadequate, pilot in command (contributing factor) - lack of total experience in kind of aircraft, pilot in command (contributing factor) - landing gear,nose gear - overload ## Analysis The student pilot was testing out a new set of rotor blades that he had recently changed. The pilot reported that the gyrocopter unexpectedly shot straight up into the air 50 feet during the takeoff ground roll. He had trouble maintaining control, stating that the aircraft immediately yawed to the left and it felt like the left rudder was being held. The pilot made a pattern circuit and decided to land in a dirt area adjacent to the runway. He said he landed nose low in soft dirt, which broke the nose wheel off, slid 30 feet and then nosed over. An FAA inspector examined the aircraft and reported that the main rotor, rotor head, and the empennage control surfaces were destroyed. ## Factual narrative On August 18, 1998, at 1208 hours Pacific daylight time, a homebuilt experimental Clark Barnett J4B2 gyroplane, N694, nosed over during a landing at the Yuba County airport, Marysville, California. The aircraft, owned and operated by the pilot under 14 CFR Part 91, was destroyed in the accident sequence. The student pilot sustained minor injuries. Visual meteorological conditions prevailed at the time and no flight plan was filed for the local area personal flight. The pilot stated that he had recently purchased the gyroplane and wanted to test out the new set of rotor blades that had been installed to see if they would spin up. According to the pilot, after he reached a certain speed while on the runway, the gyroplane shot up in the air approximately 50 feet. For a short period of time he was able to level it out, but the plane immediately yawed to the left. The pilot applied right stick and he reported that it seemed like left rudder was being held. After he made a complete circle to the left he decided to land in the dirt by the runway. According to the pilot, he landed nose low and broke the nose wheel off. He reported he slid for 30 feet and nosed over. The pilot stated that the rotor blades, rotor head, and propeller were destroyed. Some damage was done to the tail section and stabilizer. The Federal Aviation Administration investigator reported that the gyrocopter was destroyed after the rotor blades hit the ground. He reported that the pilot had altered the rotor blades. ## Aircraft - Registration: [N694](https://openairdocs.org/deregistered/N694-2018-01-23), registration cancelled 2018-01-23, S/N 169, built 1997 (OpenAirDocs) - Reported make and model: Clark BARNETT J4B2 (BARNETT J4) - Registry model: [Clark Jesse BARNETT J4B2](https://openairdocs.org/model/clark-jesse-barnett-j4b2) (registry code 05601HW) (OpenAirDocs) - Registry engine: [Subaru ALL MDLS A/B](https://openairdocs.org/engine/subaru-all-mdls-a-b) (registry code 59050, 4 cycle) (OpenAirDocs) - Category: Gyroplane, amateur-built - Serial number: 169 - Airframe hours: 7 - Engines: Subaru EJ22 reciprocating - Damage: Destroyed - Flight: Personal, Part 91 - Registered owner: Thomas J. Burns - Airworthiness certificate: Special, Experimental (Special) - Last inspection: Annual, April 1, 1998, 2 hours before - Airport: MYV, Yuba County ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 63; student; medical: class 3, valid medical--w/ waivers/lim; seat: front; flight hours: 35 total ## Weather - Conditions: Visual (VMC), Day - Wind: 150° at 8 knots - Visibility: 20 statute miles - Lowest ceiling: none - Temperature: 75 °F, dew point 59 °F - Altimeter: 30.00 inHg - Observed at: MVY, 3 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 19980818021269A](https://openairdocs.org/incident/19980818021269A), Aug 18, 1998: Amtr BARNETTJ4B, Marysville, CA, Destroyed. Gyro copter was approx 30 feet above the ground when it lost a main rotor blade and crashed. (-23)rotorcraft was flying up and down the taxiway when in a turn,… 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.