# NTSB LAX04LA191: North American Aviation Div. Navion, N91729, Page, AZ, April 8, 2004 - Type: NTSB accident investigation - Classification: Accident · No injuries · Limited investigation · Final report - Date: April 8, 2004, 09:16 local (16:16 UTC) - Place: Page, AZ - Coordinates: 36.926109, -111.448333 - Nearby events: https://openairdocs.org/map.md?lat=36.9261&lon=-111.4483&mi=10 - Phase of flight: [Initial climb](https://openairdocs.org/ntsb-phases/350) (OpenAirDocs' grouping) - Highest injury: No injuries - Injuries: 3 uninjured - Status: Completed, report June 8, 2005 - Report: Approved by Office Director - Parties: Federal Aviation Administration - NTSB case key (mKey): 59093 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=LAX04LA191 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/59093/pdf - Page: https://openairdocs.org/ntsb/LAX04LA191 ## Probable cause the pilot's failure to attain and maintain a sufficient airspeed, which led to an inadvertent stall mush in high density altitude conditions. ## 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 - weather condition - high density altitude - airspeed - not obtained/maintained, pilot in command (cause) - stall/mush - inadvertent, pilot in command (cause) - In flight collision with terrain/water, descent - uncontrolled - terrain condition - cliff ## Analysis The airplane stalled and collided with terrain in the takeoff initial climb. A witness reported that after liftoff the airplane climbed out of ground effect and stalled. The airplane returned back into ground effect, and the pilot lowered the nose to regain speed. He rotated out of ground effect, and subsequently stalled. The airplane returned to ground effect and, again, the pilot attempted to regain speed. As the airplane was approaching a cliff, it lifted out of ground effect and banked to the right. The left wing appeared to stall and the airplane impacted terrain in a nose and left wing low attitude. Based upon the atmospheric conditions provided by the METAR, the density altitude was calculated to be 4,896 feet. A Federal Aviation Administration maintenance inspector examined the airplane after the accident. He reported that he ran the engine, and found no anomalies or malfunctions that would have resulted in a decrease in power. ## Factual narrative On April 8, 2004, at 0916 mountain standard time, a North American Navion, N91729, collided with terrain while departing from the Page Municipal Airport, Page, Arizona. The pilot/owner was operating the airplane under the provisions of 14 CFR Part 91. The private pilot and two passengers were not injured; the airplane sustained substantial damage. Visual meteorological conditions prevailed, and a visual flight rules flight plan had been filed. The personal cross-country flight was originating from Page, with a planned destination of Grand Canyon National Park Airport, Grand Canyon, Arizona. In a written a statement, the pilot reported that prior to departure, he calculated the weight and balance of the airplane to be within the airplane's limits, by weighing persons and baggage. He received weather information from the Automated Surface Observation Station, which reported winds light and variable. He opted to depart from runway 33, and, after an uneventful run-up, he leaned the engine in an effort to compensate for the density altitude. During the takeoff roll, the pilot began rotation about 65 miles per hour (mph). The pilot further stated that the airplane climbed to about 50 feet above ground level, at which point the engine experienced a reduction of power. With the throttle in the full power position, the airspeed decreased below 60 mph, and the pilot lowered the airplane's nose in an effort to regain speed. The pilot opted to abort the takeoff, and the airplane touched down at the end of the runway. The airplane continued off the runway onto loose dirt. After decelerating for about 150 yards, the pilot maneuvered the airplane to the left in an effort to avoid a steep drop-off in terrain. The airplane turned and came to rest in a nose down position. During a telephone interview with a National Transportation Safety Board investigator, a Federal Aviation Administration maintenance inspector, who examined the airplane after the accident, reported that he ran the engine at Air Transport, Phoenix, Arizona. He stated that the engine operated normally during the run-up. He did note that the bracket holding the airbox cable was broken, allowing the cable to loosely hang. When he activated the alternate air in the cockpit he noted about 100 rpm drop in engine power. He could not ascertain if the broken bracket was a result of the impact. In a telephone conversation with a Safety Board investigator, a certified flight instructor at Page Municipal Airport reported that while performing a run-up, he witnessed the Navion attempt to takeoff. He stated that the airplane departed ground effect with about 8 to 12 degrees pitch attitude and stalled. The airplane returned back into ground effect, and the pilot attempted to regain speed for about 1,000 feet of runway. The airplane again rotated out of ground effect, and subsequently stalled. The airplane returned to ground effect and, again, the pilot attempted to regain speed. As the airplane was approaching a cliff, it lifted out of ground effect and banked to the right. The left wing appeared to stall, and the airplane impacted terrain in a nose low attitude. A routine aviation weather report (METAR) for Page was issued at 0856. It reported a temperature of 12 degrees Celsius and an altimeter setting of 29.97 inHg. Based upon the atmospheric conditions provided by the METAR, a Safety Board computer program calculated the density altitude to be 4,896 feet. The Airport/ Facility Directory, Southwest U. S., indicates that Page Municipal Airport runway 33 is 5,499 feet long and 150 feet wide. ## Aircraft - Registration: N91729 (not matched to a registry record) - Reported make and model: North American Aviation Div. Navion - Category: Airplane - Serial number: NAV-4-490 - Airframe hours: 3992.3 - Engines: Continental IO-470-D 260 horsepower reciprocating - Damage: Substantial damage - Flight: Personal, Part 91 - Operator: Ken Whittall-Scherfee - Registered owner: Ken and Laura Whitall-Scherfee - Airworthiness certificate: Standard, Normal - Last inspection: Annual, April 25, 2003, 79.8 hours before - Departed: PGA, Page, AZ - Destination: GCN, Grand Canyon, AZ - Flight plan: VFR - Airport: PGA, Page Municipal Airport, runway 33, 5,499 × 150 ft, asphalt ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 46; injuries: none; private; airplane ratings: single-engine land; medical: class 3, valid medical--no waivers/lim.; last flight review May 13, 2003; seat: left; flight hours: 293 total, 242 in this make and model, 216 as pilot in command, 27 in the last 90 days, 13 in the last 30 days, 3 in the last 24 hours ## Weather - Conditions: Visual (VMC), Day - Wind: variable at 5 knots - Visibility: 10 statute miles - Lowest ceiling: none - Temperature: 54 °F, dew point 37 °F - Altimeter: 29.96 inHg - Observed at: KPGA ## 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 20040408007449A](https://openairdocs.org/incident/20040408007449A), Apr 8, 2004: Tmpson NAVIONA, Page, AZ, Substantial damage. (-23) During a take-off from Page, AZ (pga) and as witnessed by another pilot, the pilot (plus 2 passengers) encountered a stall after leaving ground effect @… 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.