By David Kenny
Midair collisions are mercifully rare, perhaps in part because pilots pay so much attention to avoiding them. The Air Safety Institute documented just 10 in 2009, but seven were fatal. Airport traffic patterns have classically been the site of the largest number of midairs, which makes sense: There are usually more aircraft operating in closer proximity there than anywhere else. (The airspace above VORs is another high-risk area, though increasing use of GPS navigation may be reducing that risk somewhat.)
A small number of midairs occur at towered fields, where part of the blame often falls on air traffic control. More common is a failure to see and avoid at nontowered fields, particularly among traffic converging on final. Much rarer, but difficult to excuse, are collisions between aircraft deliberately flying in close proximity without the benefit of actual training in formation flight.
On Oct. 10, 2009, two Cessna 150s collided during climbout following a low pass over the Pineville Municipal Airport near Alexandria, La. The airplanes had taken off from Esler Airport nine nautical miles away with the intention of flying in formation to Pineville and doing one low pass before a full-stop landing. The collision severed the vertical stabilizer of the lead airplane and collapsed its right wing, leaving it uncontrollable; both people on board were killed. The pilot of the airplane in the wing position survived with minor injuries. His passenger was seriously hurt.
The wingman told investigators that they’d planned to maintain a separation of about 100 feet, with the wing remaining behind and to the right of the lead. As they climbed out following a low pass at about 200 feet agl, the lead pilot radioed that he intended to turn right to join the downwind (Runway 23 at Pineville has right traffic). As the wingman cautioned the lead not to turn too sharply, the lead banked right at an estimated 45 degrees. The wingman pitched up and rolled to the right but was unable to avoid the collision. A local photographer happened to be taking pictures of the flight. An image snapped immediately after the collision “...showed the lead airplane inverted, the right wing buckled towards the fuselage and the empennage separated from the aft baggage bulkhead. In addition, lead's separated vertical fin and various debris was suspended in air near the lead airplane. In this photo the wingman’s airplane appears to be in a right bank in excess of 90 degrees.”
Both pilots held private pilot certificates and valid third-class medicals. The best available estimate suggests that the 53-year-old lead pilot had between 550 and 600 hours of total flight experience. There is no record that he ever received any formation training. The 48-year-old wingman claimed almost 900 hours, and though he’d never trained in formation flying, he told investigators that he flew formations about once a month.
The Cessna 150 is not what most pilots would consider a fast airplane, but it’s still fast enough to get you into trouble if you operate without enough margin for error. An airspeed of 90 statute miles per hour works out to 132 feet per second. Even if they’d slowed to 60 during climb-out, 100 feet of separation would give the wingman barely one and one-eighth seconds to react to a sudden maneuver by the lead. It wasn’t enough.
Like so many other things in aviation, formation flying isn’t intrinsically dangerous ... if the pilot takes the time to learn to do it well, calibrates the operating margin to a realistic assessment of the skills of everyone involved, and identifies the ways out before they’re needed. And like everything else in aviation, it’s not a game. Close to the ground and close to other aircraft, things can get serious very, very quickly.