Incident Overview
On September 7, 2022, at approximately 1453 mountain standard time, a Cessna 750, registration N15TZ, sustained substantial damage during a landing at Phoenix-Mesa Gateway Airport (IWA) in Phoenix, Arizona. The aircraft was operating as a Title 14 Code of Federal Regulations Part 91 positioning flight from Tucson International Airport (TUS). The pilot and co-pilot reported no injuries.
Preflight Events
Before the accident flight, while the airplane was parked at TUS, a mechanic observed hydraulic fluid leaking from the nose landing gear area, forming a puddle on the ramp. The mechanic informed one of the pilots, who indicated that they were en route to Iowa and would address the issue there.
Cockpit voice recorder (CVR) data captured a conversation after boarding, where a pilot remarked about a leak outside, stating "it's not water." Another pilot confirmed the leak but could not identify its source. They also discussed the right wheel and the possibility of a hydraulic leak in System A. During preflight checks, they noted everything appeared functional and decided to monitor the situation, planning to check fluid levels after landing.
Departure and Diversion
Shortly after departing TUS, the landing gear would not retract despite multiple attempts. The pilot contacted air traffic control and requested a diversion to IWA. The crew observed that hydraulic System A had lost fluid and pressure. They completed the "Landing with No 'A' System Pressure" checklist. During the flight, they discussed the System A failure and noted that System A had no fluid. They also mentioned that the power transfer unit (PTU) had been pulled. The crew communicated with ATC, confirming no emergency, and later reported that all flaps possible were extended, initially limited to 15°. About 15 seconds before touchdown, they called out an airspeed of 160 knots.
Landing and Runway Excursion
The aircraft touched down on runway 30L, which is 10,401 feet long with a downhill gradient of 0.4%. The pilot reported a smooth landing at Vref speed and immediately applied the emergency brake. After traveling several hundred feet, the left main landing gear tires blew out. The pilot used rudder for directional control. At approximately 6,900 feet down the runway, the airplane veered left and departed the paved surface, causing the right main landing gear to collapse.
Video footage of the landing showed two bright flashes on the left side of the airplane shortly after touchdown. The airplane continued down the runway before veering left.
Automated dependent surveillance-broadcast (ADS-B) data indicated that the aircraft crossed the runway threshold at a groundspeed of about 154 knots.
The airplane came to rest in the runway safety area near taxiway H, facing approximately 140° magnetic. The right wing contacted the ground, and the right main landing gear remained partially attached. The slats and flaps were fully deployed, with the right wing slats buckled in several areas. The right thrust reverser was deployed, and the fuselage was buckled near the engine pylons.
Postaccident Examination
A mechanic at the accident site confirmed that both hydraulic System A and System B contained no fluid. With the landing gear handle in the down position, System A was serviced and pressurized without leaks. However, the PTU line near the right landing gear attachment was damaged, and System B would not retain fluid or pressure when serviced.
Examination of the aircraft revealed that the nose landing gear centering hydraulic flexible line was frayed and cracked near the upper fitting. When the line was removed and pressurized, hydraulic fluid flowed freely from the frayed area. Approximately one-third of the left main wheel, tire, and brakes were worn on one side. The hydraulic System B pressure line showed damage consistent with impact from the right main landing gear collapse. The emergency brake handle had been pulled twice at the pilot's seat, and brake pressurization was heard from the left main landing gear, though the left main wheel rotated freely on its axle.
Aircraft Systems
According to the airplane's operating manual, the hydraulic system is a dual closed center system with pumps driven by each engine. System A and System B are separate, with redundancy provided by a hydraulic motor/pump unit (PTU) and an electrically operated auxiliary pump. Pneumatic backup is available for landing gear extension and braking.
The airplane's flight manual specifies a maximum certified landing weight of 31,800 lbs. The Vref landing speed for the abnormal procedure (flaps 15°) was between 137 and 138 knots based on the reported weight at landing.