NTSB is just finishing a preliminary investigation on what has to be the closest call we’ve had between a GA aircraft and an airliner in years. On September 19, 2008, at 1938 local time, a runway incursion resulted in a near-collision on Runway 6 at the Lehigh Valley International Airport, Allentown, Pennsylvania. Mesa Air Shuttle flight 7138, a Canadair CRJ aborted takeoff at 120 knots skidding around a Cessna R172K that had just landed and was still taxiing on the runway. The RJ crew estimated the distance between the two aircraft at 10 feet.
The conditions were night VMC. The Cessna had just landed on Runway 6 and the tower cleared the RJ into position and hold. Tower then discussed with the Cessna pilot where he wanted to park, and cleared him to exit the runway at A-4 taxiway. You will note from the airport taxi diagram that A-4 is the first turnoff and unless the Cessna touched down right at the end, and was moving slowly, making the first turnoff might be difficult. Some 35 seconds later, the tower, assuming the Cessna was off the runway cleared the RJ for takeoff. 23 seconds after the RJ was cleared, the Cessna pilot advised the tower that he’d missed A-4 and would like to exit on Bravo taxiway.
There are multiple factors in this incident which both pilots and ATC should consider:
1. ATC apparently did not visually scan the runway prior to clearing the RJ and assumed the Cessna had cleared. It might also have been prudent to give the Cessna pilot more runway to get the aircraft slowed to taxi speed.
2. RJ crew apparently did not visually scan the runway prior to accepting the takeoff clearance- assumed the Cessna had cleared. It’s always good to verify that the runway is clear and if you can’t see for yourself, ask the tower.
3. The Cessna pilot should have notified the tower that he’d missed A-4 taxiway quite a bit sooner in my opinion. AIM section 4-4-1 and FAR 91.123 make it clear that you don’t have to roll it up in a ball to stop at the next taxiway if that cannot be done safely but you DO have to let the tower know, on a timely basis, that an amended clearance is needed. It would also be smart to SPEAK UP immediately if tower clears another aircraft to takeoff while you’re still on the runway.
Everyone was lucky – this time. Remember that no matter how routine something may seem, it can turn ugly faster than a speeding RJ can leapfrog a slow-clearing Cessna.