By Paul Bertorelli, Editorial Director
The U.S. Air Force says that an F-16 came no closer than 600 feet to a Pilatus PC-12 it intercepted while flying VFR in the Gladden MOA near Phoenix last month. The incident raised quite a ruckus when AVweb reported it earlier this month following an eyewitness report from the PC-12s pilot, Patrick McCall, who told us the F-16, one of a flight of four, maneuvered aggressively and came as close as 20 feet to his airplane. (Hear McCalls report in this podcast.)
McCall told AVweb that when his onboard TCAS tracked the approaching F-16, he maneuvered to avoid the conflict but that the F-16 countered and stayed right with him. He reported a merge from head on, then a join up by the F-16 from behind his PC-12.
A second airplane inside the MOA, a Beech Premier jet, was also intercepted and had to declare an emergency while complying with a TCAS resolution advisory that would have taken it into Class A airspace without a clearance. The Premier was also transiting the MOA VFR and both civil pilots were operating legally in the airspace.
An investigation by our sister publication, Aviation Safety, scheduled to appear in the May issue, reveals that the Air Forces account of the intercept contrasts with McCalls report. Major Miki Gilloon, Luke Air Force Bases public information officer, told Aviation Safety that the F-16s radar, head-up display and HSD display tapes showed that the F-16 approached the PC-12 on a parallel or divergent heading and got no closer than 600 feet.
She also said the F-16 did not counter the PC-12s TCAS evasive maneuvers but approached to visually identify it in order to contact the civilian pilot and educate him about the risks of transiting an active MOA. The F-16s data tapes arent releasable to the general public, according to Gilloon. However, the investigation results will be available under the Freedom of Information Act on the Luke Air Force Base web site.
The incident occurred on March 21 when the PC-12, flying VFR at 16,500 feet on a westerly heading through the MOA, transited airspace in which four F-16s were conducting a two-on-two air combat exercise. The training exercise was halted and three of the F-16s orbited in holds while the lead aircraft conducted a properly executed standard maneuver such as he might do to gain a visual contact with his flight leader or an aerial refueling tanker, Gilloon said This was a controlled maneuver to ensure that neither aircraft was placed in any danger. She said the F-16 was fully within Air Force rules to conduct the intercept.
Military controllers alerted the four-ship flight to the presence of the PC-12, but neither they nor the F-16s were aware of its identity. The civilian traffic was identified by the military controlling agency as stranger traffic, possibly military. The civil aircraft entered the MOA near our local military entry point at the altitude and airspeed comparable to an F-16 and without a VFR IFF squawk, Gilloon said.
The FAA says that the PC-12 was not receiving traffic advisories from Albuquerque Center, which owns the local airspace, although McCall told us he was receiving flight following. Once the PC-12 was identified, the F-16 flight raised its tactical floor to 20,000 feet and resumed its training.
When asked about FAR 91.111, which prohibits unplanned formation flight, Major Gilloon said Our ongoing investigation has revealed no indication whatsoever that the F-16 pilot violated any existing military practices or procedures for operating military aircraft in a MOA. While the Aeronautical Information Manual notes that military aircraft are exempt from some FARs, its unclearat least to usif 91.111 is among them. However, the Air Force considers 500 feet of separation well clear, while the civil definition of formation flight is ambiguous.
Both the Air Force and the FAA are continuing their investigation into the incident. McCall has filed a near miss report with FAA, but Gilloon said it is not USAF policy to file complaints against civilian aircraft legally operating in a MOA. For more in Aviation Safetys May report, see www.aviationsafety.com. The article will appear on the site next week.