Grand Canyon-National Park

According to the airplane's operator, the airplane was part of a flight of four airplanes that were taking an organized tour group of revenue passengers on a sightseeing tour of southern Utah. While operating in a high density altitude environment, the pilot was flying into an airport that had a 1,000-foot cliff about 400 feet from the end of the runway he was landing on. Because of the presence of the cliff, the Airguide Publications Airport Manual stated that all landings should be made on the runway that was headed toward the cliff and that all takeoffs should be made on the runway that was headed away from the cliff. The manual also stated that a go-around during landing was not possible. During his approach, the pilot encountered a variable wind and downdrafts. During the landing flare, the airplane dropped onto the runway hard and bounced back into the air. The pilot then immediately initiated a go-around and began a turn away from the runway heading. While in the turn, he was most likely unable to maintain sufficient airspeed, and the airplane entered a stall/mush condition and descended into the ground. A postaccident examination of the airframe and engine revealed no evidence of mechanical malfunctions or failures that would have precluded normal operation.

The airplane did not gain altitude after takeoff and collided with trees and terrain off the departure end of the runway. Prior to takeoff the pilot received a computerized weather briefing that showed generally good conditions. The tower controller cleared the pilot to taxi to the active runway (runway 21) and issued winds, which were 300 degrees at 10 knots, a direct crosswind. During the initial climb after liftoff, the pilot saw that the airplane had stopped climbing and he asked for and received the wind information again. With the airplane not climbing and headed directly for some trees, the pilot maneuvered the airplane towards a clearing but the left wing hit a tree and the airplane descended into the ground. The pilot reported no mechanical problems with the airframe and engines. The density altitude was calculated to be 9,481 feet. The aircraft's gross weight at the time of takeoff was 6,000 pounds. Review of the Airplane Flight Manual climb performance charts for that aircraft weight at the pressure altitude and reported outside air temperature discloses that the airplane should have had a positive rate of climb of about 1,100 feet per minute. The airport was equipped with a wind information recording system, which had four sensors. Three sensors recorded wind information at ground level only. They were placed, one each, at the approach, middle, and departure ends of the runway. Wind data was recorded every 10 seconds. The system does not have the capability to predict or warn of wind shear events. During the aircraft's departure, the approach end sensor recorded winds at 068 degrees at 1 knot; the middle sensor recorded winds at 293 degrees at 5 knots; and the departure sensor recorded winds at 302 degrees at 2 knots. At the next data sampling (10 seconds later), the departure end sensor recorded a wind increase of 10 knots, and the approach end recorded a wind shift from a headwind to a tailwind at 10 knots. A full analysis of the weather conditions indicated that due to developing convection over the runway the airplane likely encountered a wind shear (increasing tailwind) event that seriously degraded the takeoff and climb performance.

The airplane veered off the runway during a rejected takeoff, overran an airport sign, and impacted a hangar. The captain stated that during the after start checklist he moved the power levers to disengage the start locks on the propellers. Post accident examination found that the left propeller was still in the start lock position, while the right propeller was in the normal operating range. The captain was the pilot flying (PF) and the second-in-command (SIC) was the non flying pilot (NFP). After receiving their clearance, the PF taxied onto the runway and initiated the takeoff sequence. The SIC did not set and monitor the engine power during takeoff, as required by the company procedures. During the takeoff acceleration when the speed was between 40 and 60 knots, the captain released the nose gear steering control switch as the rudder became aerodynamically effective. When the switch was released, the airplane began immediately veering left due to the asymmetrical thrust between the left and right engine propellers. The PIC did not advise the SIC that he had lost directional control and was aborting the takeoff, as required by company procedures. The distance between where the PIC reported that he began the takeoff roll and where the first tire marks became apparent was about 630 feet, and the distance between where the marks first became apparent and where the airplane's left main landing gear tire marks exited the left side of the runway was about 220 feet. Thereafter, marks (depressions in the dirt) were noted for a 108-foot-long distance in the field located adjacent to the runway. Medium intensity tire tread marks were apparent on the parallel taxiway and the adjacent vehicle service road. These tread marks, over a 332-foot-long distance, led directly to progressively more pronounced marks and rubber transfer, and to the accident airplane's landing gear tires. Based on an examination of tire tracks and skid marks, the PIC did not reject the takeoff until the airplane approached the runway's edge, and was continuing its divergent track away from the runway's centerline. The airplane rolled on the runway through the dirt median and across a taxiway for 850 feet prior to the PIC applying moderate brakes, and evidence of heavier brake application was apparent only a few hundred feet from the impacted hangar. No evidence of preimpact mechanical failures or malfunctions was found with the propeller assemblies, nose wheel steering mechanism, or brakes.