A near miss (near hit makes more sense) as a Boeing 777 came within 300 feet of a small high-wing Aeronca Chief in San Francisco. Just after wheels up at 1,100 feet, United pilots were advised by ATC that they had company. Simultaneously, the airplane’s traffic collision avoidance system, (TCAS) sounded a warning.
The Boeing plane’s automated collision avoidance system instructed the pilots to “adjust vertical speed” and then “descend” to clear the smaller plane’s path. The first officer followed those directions and the flight continued to Beijing without further incident, the NTSB said The United flight’s first officer, who was flying the 777, pushed the control column forward to level the airplane…Both crew members said they saw the underside of the Aeronca as it passed overhead, coming within 200 to 300 feet of their jet.
Not one where visibility was impeded due to the nature of the aircraft. One was a high wing with a vertical blind spot. Low wing aircraft have a few areas of blocked visibility when looking down. The Aeronca pilot must have had a commanding view of a gray monster passing underneath and I expect his pants required dry cleaning afterward. Older aircraft are not required to have radios so perhaps no radio contact was available but then he would be prohibited from KSFO airspace which surely this Aeronca must have violated. That particular area is protected from 10,000 feet to the surface. How can anyone dawdle off into class Bravo airspace-right by the airport?
I’ve had two close calls over the years within less than 500 feet. Both times with no radio contact from the pilots of faster planes. Closure rates can be pretty quick and these were VFR “See and Avoid” situations.
TCAS: Went from nice to have to something higher in my priority list.
Update: While this incident is unsettling, the good news is that mid air collisions are gratefully small in number. According to the 2009 Nall Report: Out of 1.254 accidents involving non-commercial fixed-wing aircraft only 11 were midair collisions. Eleven isn’t good but certainly not a leading cause.