# NTSB DEN05FA100: CGS Hawk Two Place Arrow, Jackson, WY, June 27, 2005 - Type: NTSB accident investigation - Classification: Accident · Fatal · Field investigation · Final report - Date: June 27, 2005, 12:25 local (18:25 UTC) - Place: Jackson, WY - Coordinates: 43.626667, -110.727218 - Nearby events: https://openairdocs.org/map.md?lat=43.6267&lon=-110.7272&mi=10 - Phase of flight: [Approach](https://openairdocs.org/ntsb-phases/500) (OpenAirDocs' grouping) - Highest injury: Fatal - Injuries: 1 fatal - Status: Completed, report October 31, 2006 - Report: Approved by Office Director - Parties: CGS Aviation, Federal Aviation Administration - NTSB case key (mKey): 61813 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=DEN05FA100 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/61813/pdf - Page: https://openairdocs.org/ntsb/DEN05FA100 ## Probable cause The loss of airplane pitch control resulting from the pilot/owner's improper reinstallation of the rear locking collar on the elevator control torque tube, which allowed the torque tube to move rearward during flight and loosen the elevator control cable tension. ## Sequence of events In NTSB's coding before 2008 (https://www.ntsb.gov/GILS/Documents/codman.pdf). - Loss of control - in flight, approach - vfr pattern - base leg/base to final - maintenance,installation - improper, owner/builder (cause) - flt control syst,elevator control cable/rod - loose (cause) - aircraft control - not possible, pilot in command (cause) - In flight collision with terrain/water, descent - uncontrolled - terrain condition - ground ## Analysis Several witnesses reported that the airplane departed runway 19, and immediately climbed to approximately 500 feet above ground level (agl), while maintaining runway heading. The airplane then turned left onto the crosswind leg of the traffic pattern and maintained a slight climb. One witness, who was in a vehicle, observed the airplane in normal flight on a left downwind for runway 19 at an altitude of 800 to 1,000 feet. The witness observed the airplane turn left (west) onto the base leg for runway 19 "in normal flight and was descending but not what appeared to be abnormal." The airplane continued its nose-low descent toward the terrain until approximately 200 feet agl, the airplane began a "steeper" nose-low descent toward terrain. The airplane then impacted terrain in a wings level attitude, bounced, nosed over, and came to rest inverted. During the descent, the witness did not noticed any movement of the elevator or other flight control surfaces, or any in-flight structural failure of the airplane. The accident flight was the third flight conducted by the pilot since he had completed repairs after sustaining a hard landing with the airplane. In order to complete the repairs to the airplane, the pilot had to removed the elevator and aileron controls located in the boom tube. NTSB materials laboratory examination of the aileron and elevator controls revealed no features or marks were found at a location of approximately 5/16-inch forward of the original location of the rear locking collar on the torque tube surface, with the exception of two distinct circumferential marks. The featureless surface, confirmed by testing, indicated that the locking collar was slightly torqued and that the torque tube had moved relatively slowly over this distance, possibly with two stops. The torque required to loosen the rear locking collar screw was measured at 3-inch pounds, representing a minimal snugging of the collar bolt and collar on the torque tube. According to the manufacturer, a 3/16-inch aft movement of the torque tube would be enough to lose any tension in the elevator control cables. The rear edge of the cutout on the boom tube for the rear control stick displayed three locations where paint had been removed, but there was no material deformation. The lack of deformation is consistent with light contact by the control stick, which would be expected if the control stick had been pulled rearwards manually. A lightly rubbed area on the aileron crank revealed laterally orientated arced lines on the surface and corresponding laterally orientated smeared surface on the upper front bulkhead tube. No evidence was found to indicate that an inspection mirror had been trapped in the boom tube. ## Factual narrative HISTORY OF FLIGHT On June 27, 2005, approximately 1225 mountain daylight time, an unregistered CGS Aviation Hawk Two Place Arrow experimental light-sport airplane was destroyed when it impacted terrain following an uncontrolled descent during the base leg of the visual approach to runway 19 at Jackson Hole Airport (JAC), Jackson, Wyoming. The commercial pilot, who was the sole occupant and owner of the airplane, sustained fatal injuries. Visual meteorological conditions prevailed, and a flight plan was not filed for the Title 14 Code of Federal Regulations (CFR) Part 91 personal flight. The local flight departed JAC at 1218. Several witnesses at JAC reported that the airplane departed runway 19, and immediately climbed to approximately 500 feet above ground level (agl), while maintaining runway heading. The airplane then turned left onto the crosswind leg of the traffic pattern and maintained a slight climb. Two witnesses, who were traveling southbound in motor vehicles on Highway 89 (parallel to JAC runway 01/19), reported that they observed the airplane on the left downwind leg at an altitude of 700 to 900 feet agl. One witness, who was also in a vehicle, observed the airplane in "normal flight" at an altitude of 800 to 1,000 feet flying parallel to the east of Highway 89. The witness observed the airplane turn left (west) onto the base leg for runway 19 "in normal flight and was descending but not what appeared to be abnormal." The airplane continued a nose-low descent toward the terrain. Approximately 200 feet agl, the airplane began a "steeper" nose-low descent toward terrain. The airplane then impacted terrain in a wings level attitude, bounced, nosed over, and came to rest inverted. During the descent, the witness did not noticed any movement of the elevator or other flight control surfaces, or any in-flight structural failure of the airplane. According to Federal Aviation Administration (FAA), the pilot was in communication with the JAC air traffic control tower during the accident flight. The pilot contacted the air traffic controller (ATC) and reported he wanted to depart JAC to the east with a left turn out. Shortly after departure, the pilot contacted ATC and stated he wanted to re-enter the traffic pattern and return to JAC for a full stop landing. The controller told the pilot to report left base for runway 19. The pilot reported left base for runway 19. No further communications were received by ATC from the pilot. During the communications, the pilot did not report any problems with the airplane. PERSONNEL INFORMATION The pilot, age 58, who was seated in the front seat position, held a commercial pilot certificate, issued February 25, 1970, with airplane multi-engine land, airplane single-engine land, and airplane instrument ratings. The pilot also held a type rating for Cessna CE-525S jet airplanes. The pilot was issued a third-class medical certificate on March 9, 2004, with the limitation, "Holder shall possess glasses that correct for near vision." The pilot's logbooks were not located; however, according to the pilot's March 9, 2004, medical certificate application, the pilot reported a total time of 9,400 hours, and 203 hours in the previous 6 months. AIRCRAFT INFORMATION The CGS Hawk Two Place Arrow was a high wing, 2-seat tandem airplane, constructed from aluminum tubing and Dacron covers, featuring dual 3-axis control. The orange and white accident airplane was configured with conventional fixed landing gear (a tricycle gear configuration was also available from the manufacturer). The wing (31 1/2-foot span, 147 square feet) consisted of one section per side with an aileron, 3-position flap, and aluminum wing strut. Each wing contained two 5-gallon fuel tanks, a total capacity of 20 gallons. The wings are attached to the fuselage, and a Velcro secured Dacron or Lexan "gap" cover completes the upper wing surface between the two wing sections and fuselage. The fuselage (cockpit) was an aluminum tubing construction covered with Dacron and a Lexan windscreen, which was sewn to the Dacron cover. The fuselage had four removable zipper doors which provide a full fuselage enclosure. The accident airplane was equipped with a heater which was mounted in the nose of the airplane. A single aluminum boom tube attached the fuselage and empennage. The empennage consisted of vertical and horizontal stabilizers, with rudder and elevator control surfaces. The accident airplane was originally equipped with an optional elevator trim tab. The flight control surfaces were operated via control cables. The dual stick controls were slaved via a torque tube. The torque tube assembly was routed inside the boom tube, and the rear stick was exposed through a rectangular cut-out in the top portion of the boom tube. The CGS Hawk Two Place Arrow was powered by a 100-horsepower, water-cooled, fuel-injected Hirth model 3701 engine, equipped with a three-blade IVOPROP electric in-flight adjustable, composite propeller. The engine was mounted at the rear of the fuselage, immediately aft of the wing. The accident airplane was built and completed in May 2005 by a CGS Aviation approved dealer located in West Virginia, in conjunction with partial assistance by the pilot. The airplane building records and logbooks were not obtained. According to the dealer and acquaintances of the pilot, the airplane had accumulated approximately 45 hours at the time of the accident. The accident airplane was eligible for certification in the experimental light-sport aircraft category. According to CFR Part 21.191(i)(1), after January 31, 2008, an experimental certificate would not be issued for the accident airplane. The airplane was not eligible for certification in the ultralight category due to a fuel capacity of greater than 10 gallons. According to the kit manufacturer and dealer, the pilot had intended on registering the airplane with the FAA; however, he had not completed the process at the time of the accident. METEOROLOGICAL INFORMATION At 1215, the JAC METAR (routine aviation weather report) reported the wind from 180 degrees at 4 knots, visibility 10 statute miles, sky clear, temperature 66 degrees Fahrenheit, dew point 41 degrees Fahrenheit, and an altimeter setting of 30.03 degrees inches of Mercury. AERODROME INFORMATION The Jackson Hole Airport, JAC, is a public, controlled airport located approximately 7 miles north of Jackson, Wyoming, at 43 degrees, 36.44 minutes north latitude, and 110 degrees, 44.265 minutes west longitude, at a surveyed elevation of 6,451 feet. The airport features one asphalt runway, Runway 1/19, which is 6,300 feet long and 150 feet wide. WRECKAGE AND IMPACT INFORMATION The accident site was located in sage brush-covered flat terrain approximately 575 feet west of Highway 89, and 3/4-mile north of the approach end of runway 19. Initial examination of the wreckage and accident site was completed by Grand Teton National Park personnel. With assistance from a local mechanic, the accident site was documented by the National Park Service on-scene coordinator. A global positioning system (GPS) receiver reported the location as 43 degrees 37.36 minutes north latitude and 110 degrees 43.38 minutes west longitude, at an elevation of 6,400 feet. The wreckage was distributed along a measured magnetic heading of approximately 320 degrees. The initial impact point was consistent with the fuselage and the main landing gear. The main wreckage came to rest inverted approximately 50 feet from the initial impact point. The main wreckage consisted of the left and right wings, boom tube, empennage, and fuselage tubing. The airplane wreckage was transported to a vacant hangar at JAC for further examination by the NTSB. On June 28, 2005, the wreckage was examined by the NTSB investigator-in-charge, two FAA inspectors, and the on-scene coor ## Aircraft - Registration: UNREG (not matched to a registry record) - Reported make and model: CGS Aviation Hawk Two Place Arrow - Category: Airplane - Serial number: AII-179-3701-TD - Airframe hours: 50 - Engines: Hirth 3701 100 horsepower reciprocating - Damage: Destroyed - Flight: Personal, Part 91 - Operator: John T. Walton - Departed: JAC, Jackson, WY - Destination: JAC ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 58; injuries: fatal; flight instructor, commercial; airplane ratings: multi-engine land, single-engine land; instrument ratings: airplane; medical: class 3; seat: front; toxicology performed; flight hours: 9,400 total, 15 in this make and model ## Weather - Conditions: Visual (VMC), Day - Wind: 180° at 4 knots - Visibility: 10 statute miles - Lowest ceiling: none - Temperature: 66 °F, dew point 41 °F - Altimeter: 30.03 inHg - Observed at: JAC, 1 nm away 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.