CHI03FA284 · Cessna 172S

The Cessna and Piper airplanes were destroyed when they impacted terrain after a mid-air collision. Both the Cessna and Piper aircraft were flying beneath the positively controlled Class B airspace of the Minneapolis-St. Paul International Airport. Both airplanes were operating under visual flight rules, and both airplanes were transmitting the 1200 VFR beacon code on their respective transponders. Neither airplane was required to be in radio contact with air traffic control. The student pilot in the Cessna who survived the accident reported that the CFI let him take the flight controls while they were flying straight and level. He reported that he was flying the airplane and was looking straight ahead, trying to maintain straight and level flight. He reported that the CFI put her hand on the throttle and started explaining a climb procedure. He reported that while the CFI was explaining the climb procedure, the airplane was hit by another airplane on the right side. He reported that he never saw the other airplane before the impact and that he didn't think the CFI saw it either. He reported that the CFI did not grab the controls or make any "violent maneuvers" prior to the impact. Radar data indicated that the Cessna departed Downtown St. Paul Airport (STP) at approximately 1719 to the northwest and turned right to an easterly heading, paralleling interstate highway I-94 to the east. The Cessna climbed to approximately 2,300-2,400 feet pressure altitude about 4 minutes after takeoff and remained at that altitude until impact, approximately 2 minutes later. The Cessna was traveling approximately 98 knots average ground speed during the 2 minutes prior to impact. The Piper departed South St. Paul Municipal Airport (SGS) at approximately 1719. Approximately 4 minutes after takeoff, the Piper turned to the northeast on a heading of about 027 degrees. The Piper climbed from about 1,900 feet pressure altitude to about 2,300 feet pressure altitude during the 2 minutes prior to impact. The relative bearing between the Piper and the Cessna was about 60 degrees. The radar data indicated the Piper was traveling at approximately 107 knots average ground speed during the 2 minutes prior to impact. Approximately 36 inches of the Cessna's outboard right wing structure was found lodged in the wing root of the Piper's left wing, and was located with the main wreckage of the Piper. The Piper's left wing exhibited a span-wise crease about five feet long in the lower wing skins forward of the flap. The Cessna's right wing leading edge had two distinct dents that were spaced a similar distance apart as the Piper's wing tie-down ring and jack pad. The aft left side of the Piper's fuselage in the vicinity of the registration number exhibited black, rubber-like transfer marks. The right tire from the Cessna's main landing gear had white scuff marks on the right side of the tire.

Verbatim NTSB analysis and probable cause from the NTSB dataset