NTSB Factual Report

On September 02, 2002, at 1202 mountain standard time, the right wing of a Cessna 172I, N404SW, struck the pavement after the airplane encountered jet blast from a departing commercial transport airplane while taxing to the ramp after landing at Tucson International Airport (TUS), Tucson, Arizona. The airplane sustained substantial damage, and both the certified flight instructor (CFI) and student pilot were uninjured. Arizona Aero-Tech was operating the airplane as an instructional flight under the provisions of 14 CFR Part 91. Visual meteorological conditions prevailed, and no flight plan had been filed. The local instructional flight departed Tucson about 1100.

According to the CFI, they had just landed on runway 11R and were taxiing to the west ramp via taxiway Alpha as directed by ground control. A United Airlines Boeing 737 was holding short at taxiway A4 (Alpha Four) for takeoff on runway 11L. The CFI was discussing jet blast awareness with his student as they were passing behind the jet. They taxied as far to the right side as they could to avoid the potential hazard. The Boeing 737 was not on the ground frequency. It was monitoring the tower while awaiting takeoff clearance.

As the Cessna began to merge back in toward the middle of the taxiway, the left wing rose into the air. The right wing hit the pavement two times as the airplane oscillated and then weathervaned towards the jet. The propeller also struck the pavement. After the airplane stabilized, the instructor shut down the engine, and turned the master electrical switch off. The CFI and student exited the airplane.

Tucson Airport Police interviewed Air Traffic Control (ATC) tower personnel. ATC cleared the United Boeing 737 for takeoff. It had been holding short of runway 11L at taxiway intersection A4 in proximity to where the Cessna was taxiing. Reportedly, no personnel in the tower cab could determine where the Cessna was in relation to the 737 as the jet throttled up and began its takeoff roll. Both airplanes were on their respective frequencies for their related positions on the movement area.

Air Traffic Control Order 7110.65N, 3-1-4 states that local and ground controllers shall exchange information as necessary for the safe and efficient use of airport runways and movement areas. There are also directions in Chapter 2 to issue cautionary information to any aircraft when in the opinion of the controller; wake turbulence may have an adverse effect on it. "The words jet blast may be used by controllers in lieu of wake turbulence."

The National Transporation Safety Board investigator obtained the radio transmission recordings for Tucson International Airport's tower and ground frequencies. The United 737 had been cleared to taxi from the gate to A4 prior to the Cessna coming onto ground control frequency. The local controller handed off the Cessna to the ground controller's frequency after the landing on runway 11R, and after it had crossed 11L (the parallel runway). Ground control issued instructions for the Cessna to make a left on taxiway Alpha and hold short of runway 21.

The pilot followed the transmission with a read back of the clearance and hold short instructions. The recording demonstrated that after receiving clearance to taxi, 1 minute 51 seconds went by before the Cessna radioed to advise the ground controller of the incident. "The United 737 jet blast had popped the airplane over and they were deciding where to go as the prop was damaged." The controller issued only one instruction in that time frame, which was to have another taxiing aircraft give way to the Cessna. Overall, six calls to ground control were on the tape during the 5 minute 44 second period prior to the accident. ATC issued no safety alerts or cautionary advisories.

Examination of the airplane revealed damage to the right wing spar. One propeller blade was twisted, the other sustained tip damage. Strike marks were on the pavement near the right side boundary of taxiway Alpha. Tucson Airport Authority reported taxiway Alpha as being 75 feet wide and taxiway A4 having a length of 425 feet.

NTSB Probable Cause

the certified flight instructor's failure to maintain an adequate distance from a jet during taxi. A factor was the local/ground controller's failure to issue a safety alert or cautionary advisory to the pilot with regards to the jet blast of the departing Boeing 737.