What Happened
On April 9, 2018, about 8:48 p.m. mountain standard time, Piper PA-24-260 N9456P crashed shortly after takeoff from Scottsdale Airport, Arizona. The airline transport pilot, student pilot, and four passengers were killed. The airplane was destroyed by impact and a postcrash fire.
Earlier that evening, the airline transport pilot had flown from North Las Vegas to Scottsdale to collect the group. That inbound leg was his first flight in the airplane. It landed at 8:18 p.m., and surveillance video showed the occupants beginning to board about 10 minutes later.
The student occupied the front left seat and the airline transport pilot sat on the right. Four passengers occupied the middle and aft seats. The investigation could establish those seating positions from video and photographs, but could not determine who was manipulating the controls during the accident sequence.
The airplane departed runway 03 in nighttime visual conditions. Surveillance video and witnesses showed the wings rocking during the takeoff and shortly after rotation. The controller noticed the movement and thought the engine did not sound as though it was producing enough power.
When the controller asked whether the airplane was having difficulty, the reported response was that the occupants were fine and were in training mode. The airplane continued away from the airport. The final recorded radar point placed it only about 200 feet above the ground.
A traffic camera approximately half a mile northwest of the runway end captured the aircraft turning left. As the turn progressed, its bank increased and it began descending. The wings were nearly vertical before it struck the ground.
Investigation Findings
Investigators calculated that the airplane departed about 135 pounds above maximum gross weight and with its center of gravity 2.22 inches beyond the aft limit. The takeoff was therefore outside two separate loading limits.
Excess weight reduced the available performance margin. The aft center of gravity also affected pitch behavior and longitudinal stability, meaning the aircraft’s tendency to maintain or recover a stable pitch condition. The NTSB noted that an excessively aft center of gravity could allow premature rotation and reduce stability.
The Board concluded that the pilot likely failed to maintain airspeed during the initial climb and lost control. That finding was supported by the low altitude, the increasing bank, and the subsequent descent seen in the recordings.
The engine investigation found a preexisting defect. The number 3 cylinder’s outer intake-valve spring was broken, with fracture features consistent with fatigue. Damage on the springs indicated the break likely occurred before the accident and had gone undetected.
The NTSB found that the broken spring likely reduced available engine power. That reduction might not have been noticeable on previous flights, but it became more consequential with the accident airplane’s overloaded condition. The report identified no other pre-impact engine or airframe anomaly that would have prevented normal operation.
The cause therefore combined aircraft loading and control, with reduced power as a contributing factor. It did not describe a proven total engine failure immediately after takeoff. That distinction matters because an aircraft can still produce power and lack the climb performance its pilot expects.
Toxicology showed evidence of prior cocaine and ecstasy use by the student pilot. The findings indicated past rather than immediate use, and the NTSB stated that those drugs were not factors in this accident. They do not belong in a substitute explanation for the loading and power findings.
The probable-cause statement referred to the flight instructor’s failure to maintain control. That finding does not resolve which occupant’s hands were on the controls at impact; the investigation explicitly left that point undetermined.
NTSB Probable Cause
The flight instructor’s failure to maintain airplane control during the initial climb as a result of the airplane being loaded above its maximum gross weight and beyond its aft center of gravity limits. Contributing to the accident was a degraded engine power output due to a preexisting engine cylinder intake valve spring failure, which further reduced the airplane’s climb capability.
Safety Lessons
The following takeaways apply the investigation findings to flight planning and cockpit decisions.
- Calculate both weight and center of gravity. Seat availability does not establish that a full passenger load is within limits. Verify actual occupant and fuel loading against the approved envelope before departure, including the effect of passengers in the aft seats.
- Keep initial-climb margins conservative. A modest power reduction can become critical when loading has already consumed performance margin. Confirm expected takeoff and climb performance using the aircraft data and avoid treating prior flights as proof that the present loading is acceptable.
- Define command and intervention responsibilities. When a student and instructor or more experienced pilot share the cockpit, clarify who is flying and who will intervene. That does not replace the loading calculation, but it keeps control responsibilities clear when performance is abnormal.
Watch the Full Analysis
Frequently Asked Questions
Q: Why did the Piper Comanche crash after takeoff at Scottsdale?
A: The NTSB cited loss of control during initial climb with the airplane above maximum gross weight and beyond its aft center-of-gravity limit. Reduced engine power from a preexisting valve-spring failure contributed.
Q: Was the Scottsdale airplane overweight?
A: Yes. Investigators calculated that it departed 135 pounds above maximum gross weight and 2.22 inches beyond the aft center-of-gravity limit.
Q: Was the student flying when the airplane crashed?
A: The student was seated on the left and the airline transport pilot on the right, but investigators could not determine who was manipulating the controls during the accident.
Sources and References
