Eye Spy

See-and-avoid usually works, but densely packed airports can present unseen danger

0

Nearly every pilot has stuck his head in the lions mouth.

You realize its happened only after the crisis has passed. You have the metallic taste of fear in your mouth and the pounding of your pulse to remind you of the fleetingness of your mortality. Its not much fun, but at least you have seen the enemy and will have a better shot at recognizing him next time.

If there is a next time.

Busy airspace is one place where constant vigilance is the order of the day. During good weather, that vigilance depends on scanning outside the airplane and being alert to the dynamics of the airspace as well as the possibility of traffic.

Some pilots, particularly those who routinely fly IFR in high performance airplanes, tend to rely on controllers to call traffic. In addition, they tend to focus more on whats happening inside the cockpit, even during phases of flight where their attention should be focused outside. Finally, some pilots flying a routine route will assume this flight will be the same as the last.

Sometimes, all the elements add up to catastrophe.

A Learjet 55 was leaving Boca Raton, Fla., en route to Fort Pierce, Fla., 68 miles to the north, on a positioning flight to have the aircrafts registration number changed. The pilots had filed an IFR flight plan and planned to open it with Palm Beach Approach after takeoff. Boca Raton, an uncontrolled airport at the time, has since opened a control tower due to the volume of traffic and the mix of airplanes.

Good Credentials
PIC of the Lear flight was the chief pilot and Director of Training for the Part 135 operation that owned the airplane. He had been hired a year earlier as a contract pilot and a month earlier had been brought on as a full-time salaried pilot.

The 40-year-old pilot had more than 15,000 hours of flight experience, including 100 in the Lear in the previous 90 days. His previous biennial flight review, five months earlier, was in a Lear 35.

His co-pilot for the flight was a 35-year-old contract pilot who had 1,500 hours total time, including 850 multi and 110 hours in type. According to the NTSB accident report, he did not have a Learjet type rating. Also on board was another company contract pilot, along as a nonrevenue passenger.

The Lear was equipped with a cockpit voice recorder that captured the conversation of the pilots aboard as well as their radio transmissions. The conversation between the pilot and the copilot was relaxed, yet it was clear the pilot was helping the copilot learn the nuances of the machine. In fact, at one point he even explained why one of the items on the starting engines checklist should not be followed exactly, particularly when flying in developing countries.

As they completed the preflight checklists and taxied to runway 23, they monitored the airports Unicom frequency and even started making comments about the quality of the landings they were seeing. At one point, two airplanes were on final simultaneously and nearly collided in mid-air.

The co-pilot remarked that the resulting go-arounds looks like formation flying to me. Little did he know what a harbinger it was.

The Learjets route would take the flight within spitting distance of seven public airports (including one Class C) and nine private airports. In addition, there were three more public airports within 10 miles to the south and southwest – the direction theyd be taking off.

The pilot allowed the co-pilot the takeoff, and the flight took off at 11:40:37. As the jet began its climb to its intended initial cruising altitude of 2,500 feet, it announced a right turn to 270. As the co-pilot pondered the power settings, the pilot/instructor gave him rein to work. You can do whatever you feel comfortable with. You play with it. Figure out what you need to do, he told the co-pilot.

The airplane was climbing to 2,500 feet at about 180 knots. The pilot switched to the radio that was tuned to Palm Beach Approach.

Meanwhile, Down the Road
As the pilots of the Lear were going through their engine starting checklist, the pilot of an Extra 300S fired up his airplane at Pompano Air Park, an airport only eight miles to the south.

The pilot was an airshow pilot who also conducted aerobatic instruction.He monitored the ATIS and contacted the ground controller for taxi to runway 15.

He planned a 20-mile flight to Willis Gliderport, a fly-in community where he lived. The route to the private airport would take him west of the traffic pattern of Boca Raton and underneath the floor of the outer ring of Palm Beachs Class C airspace.

He was well-known to the controllers at Pompano, and they exchanged a bit of friendly banter as he taxied. He was cleared for takeoff and his wheels cleared the ground about three minutes before the Learjet left Boca Raton.

At 11:40:10 he was granted a frequency change. His parting words to the controller were that he planned to go to the Florida Keys the next day.

The radar track showed the Extra tracked directly toward its destination at 170 knots. The altitude held steady at 2,400 feet, with a momentary blip up to 2,500 feet, then back down to 2,400 feet.

As the Lear turned toward the west, it was climbing through 1,400 feet, 1,700 feet, 2,000 feet and 2,300 feet. The co-pilot began running the trim to level out at 2,500 feet.

Weather at the time was reported as 25,000 scattered, visibility 10 miles, temperature 92, dewpoint 68, wind variable at 5 knots.

Witness accounts vary somewhat about what happened next. In fact, some of them are so at odds with more objective facts that it shows how witnesses can be unreliable at times. However, most of the accounts are consistent in several respects. The Extra pilot apparently saw the Lear at the last second, turned right and pushed the nose down. It was unclear whether the pilot of the Lear made any attempt at evasive action. In any event, it was too late.

The left wing of the Extra struck the left wing of the Learjet. The nose of the Extra struck the aft fuselage of the Lear just over the wing.

Much of the right wing was ingested by the Learjets left engine. The right horizontal stabilizer punched into the tail of the Lear and stuck there.

The jet broke in half where the nose of the Extra struck it. As the jets nose plunged toward the ground, it exploded and trailed fire. Witnesses all reported seeing a parachute deploy, perhaps the emergency bail-out chute worn by pilots of aerobatic airplanes, but the NTSB report is mum on the parachutes fate. The pilot apparently was not wearing it. The Extra pilot and all three aboard the Lear were killed in the crash.

The wreckage rained down on three gated communities in west Boca Raton. The initial wreckage, primarily the engine and left wing from the Extra, were found 2.5 miles southwest of the Boca Raton airport. The Learjet and the fragments of the Extra it carried went a little farther.

The main fuselage section, including the cockpit, struck a condominium and penetrated the 4- to 6-inch concrete roof of the auxiliary generator room, where it continued to burn. No one on the ground was injured.

An analysis of the visibility from the Lear cockpit showed the Extra would have been clearly visible as the aircraft closed. That is, no aircraft structure would have interfered with the line of sight from the pilot sitting in the left seat.

The pilot in the right seat would have had difficulty seeing the Extra because of the structure and the person sitting in the left seat.

The NTSB report made no mention of any kind of collision avoidance device being installed on the Learjet, but given the Lears performance and sophistication it would not be unusual for TCAS I to be installed. Regulations require that an installed TCAS must be on. However, TCAS was not required on the Learjet.

The Extra, with its bubble canopy, had no impediments to visibility for the pilot.

See and avoid is a time-honored method of detecting conflicting traffic. However, it cannot work if pilots focus their attention inside the cockpit two miles from an airport.

The accident report also includes a chilling witness account. He describes the Extra as performing stunts as it flew along.

There are some discrepancies in the account of this witness, in that he thought the Extra was going south and the Lear was going north. However, the witness said that, among other things, the airplane flew vertical, twisted and spun down again at a very fast rate.

If this witness account is considered credible, then the Extra pilot was clearly out of bounds. Although he was far enough from an airway to do aerobatics, he was over populated terrain and far too close to an airport to make such activities wise.

Some pilots swear by innovations like collision avoidance gear, saying its the airplanes you dont see that surprise you. That may be true, but you cant see what you dont look for.

The traffic scan is an elementary technique, yet its one that some pilots, inexplicably, seem to think theyre above. For safetys sake, the odds improve if you make sure youre not one of them.


Also With This Article
Click here to view “Technology can aid avoidance, within limits.”
Click here to view “Crash Diagram.”
Click here to view “Radar ground track and altitude readout.”

-by Ken Ibold

LEAVE A REPLY

Please enter your comment!
Please enter your name here