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Lack of Clarity Leads to an Accident

Uncertainty makes for an accident waiting to happen.

A Cessna 210N, with only the pilot aboard, took off on a clear morning from Dekalb-Peachtree Airport (KPDK) and flew northbound. A few minutes later, the pilot radioed the tower that he wanted to return.

“Do you need any assistance,” the tower controller inquired, “or are you just coming back inbound?”

“Coming back inbound,” he said.

A minute or so later, the pilot reported, “I’ve got smoke in the cockpit, and the gear won’t go down.”

The controller offered the pilot a straight-in approach to Runway 20L, which the pilot acknowledged. When the airplane appeared to be heading somewhat to the left of the expected track, the controller asked the pilot whether he intended to make a left base to 20L or if he would rather make a right base to 27, which intersected 20 at midfield.

The pilot replied that he wanted to do a right-base entry for Runway 2R. He said that he still didn’t think the gear was down. “Say your request,” the controller replied.

“I think I would like to get the gear down, and I still got this smoke.”

The controller asked if the pilot would like to make a fly-by to check the gear position and if he still had the smoke.

“Yes, I do,” the pilot replied. “I just have the window open.”

“And if you want to, do a fly-by on Two right to check the gear?”

“OK, will do.”

Half a minute later, as the pilot turned to the right, the controller asked whether he was making a tight base for 2R or intended to use Runway 34, whose threshold was about 2,000 feet north of 2R’s. The pilot replied that he intended to fly past the tower, which was at midfield, for a gear check. While the 210 was still on the base leg, the controller told the pilot that the gear appeared to be down.

“I’ll land it if the gear looks down,” the pilot said. “It feels up to me.”

The controller cleared the Cessna to land on 2R, but then revised her assessment of the gear position and instructed the pilot to go around. The Cessna touched down momentarily and then climbed away. A few seconds later, the controller advised the pilot that one gear leg was not in the down position, adding: “It did not look like it was locked in place, and I do see smoke coming from the cockpit. Say your request.”

The pilot did not answer. In the meantime, another pilot on the frequency suggested to the controller that she tell the pilot to pull his gear circuit breaker because he probably had a problem with the electric hydraulic pump. The controller asked the pilot whether he had copied that transmission but again received no response.

The 210 made a right 270 and appeared to be approaching Runway 27 to land. At this point, the tower advised the pilot that there were vehicles on Runway 27 and instructed him to go around again. Shortly afterward, the tower controller advised the pilot that the vehicles had driven off the runway. She suggested that the pilot could make a left turn to land on 2L and cleared him to land on any runway.

The National Transportation Safety Board’s narrative is not clear, but it appears that the pilot did turn left as the controller suggested and then, being too close to 2L, may have tried to make 2R. In any case, the Cessna struck the ground between the runways, possibly because it stalled out of the turn or because the pilot, who had moved from the left seat to the right, was distracted or disabled by smoke or flames. It immediately caught fire. Rescuers arrived within seconds—the vehicles on Runway 27 were fire trucks that had stopped there expecting the Cessna to land on 2R—but they were unable to save the pilot.

Investigators determined that a chafed wire, most likely one supplying power to the flap motor, had shorted under the floor beneath the pilot’s seat, igniting hydraulic fluid presumably from a preexisting leak. The fire consumed a flexible hydraulic hose, and the leaking fluid fed the fire.

Each player in this drama was operating in partial ignorance, relying on others to provide certainty that they did not have.

Consider the predicament of the pilot. He was a 750-hour private pilot with single- and multiengine privileges as well as an instrument rating, so he was not a novice. The airplane was rented, so he was probably not intimately familiar with its maintenance history. Presumably, everything seemed fine when he took off. The gear probably retracted at first, because some time elapsed before the pilot told the tower that he wanted to return.

The likely sequence of events was that the flexible hydraulic hose, previously damaged by the shorting wire, finally burned through as the flaps were being retracted. After a short time, the landing gear, which lacks mechanical locks and is kept up by trapped hydraulic pressure, began to sag. The green lights flickered, and the electric hydraulic pump ran briefly. After a minute or two of this, the pilot realized he could not continue the flight.

At some point during the return to the airport, smoke appeared in the cockpit.

There is no emergency more urgent in an airplane than an in-flight fire, and you know what they say about smoke. The pilot now found himself entangled in conflicts. On the one hand, he did not want to wreck the club airplane he was flying if he could manage to get the gear down. On the other hand, he had to get onto the ground quickly, in case the smoke turned into flames. The emergency procedures for electrical fire in flight require turning off all the electrics and shutting the air vents, but he evidently did not know this because he opened the window. Turning off the electrical services would have deprived him of communication with the tower, and he was hoping the tower could elucidate the gear situation for him. Actually, turning off electrics would not have done any good in this case because the hydraulic oil was already burning—but we know that only in hindsight.

The one clue the pilot may have had was the odor of the smoke. Burning insulation and semiconductors smell different from burning oil, but getting a pilot’s license does not require being able to distinguish the two.

The tower controller was similarly conflicted. She had mobilized the emergency equipment, but she evidently believed the pilot’s principal problem was his landing gear because “smoke in the cockpit” can mean anything from a faint odor to a choking cloud, and the pilot did not declare an emergency or express an urgent need to get onto the ground. Pilots often minimize their troubles, but heroic reticence is ill-advised if it gives potential helpers the impression that the problem is less serious than it is.

It appears possible that the collision with the ground may have occurred because the fire broke through the floor under the pilot’s seat, and he lost control of the airplane while trying to move away from the flames.

The NTSB included in the probable cause “the pilot’s in-flight decision to continue flight with…known airplane deficiencies.” That was an odd way to put it. I would have said that the root problem was the pilot’s failure to convey sufficient urgency to the controller. She saw smoke trailing from the cockpit, and yet she felt free to make the pilot go around twice. If he had been more insistent, she might have instead said, “Land anywhere—on the grass if you wish.” Whether the outcome would have been any different, however, is not ours to know.

This story appeared in the August 2020 issue of Flying Magazine

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