Due diligence

(CEN14FA035)

By David Jack Kenny

Technological advances are rarely unmixed blessings. Anecdotally, at least, more drivers tailgate more flagrantly since the adoption of anti-lock brakes. Datalink services that bring radar images into the cockpit have tempted more than one pilot to fly too close to thunderstorms.  The aura of precision attached to fuel computers capable of pinpointing consumption down to the ounce has been known to mask the first rule of data processing: Garbage in, garbage out.

Initial reports that a King Air C90 had succumbed to apparent fuel exhaustion on the short hop from Pine Bluff, Arkansas, to Bentonville (about 172 nautical miles straight-line distance) inspired some incredulity. How could anyone able to operate a King Air be too cheap or too careless to assure he had enough fuel for the flight? As so often happens in aviation, though, the truth wasn’t quite that simple.

Prior to departing from Pine Bluff on the morning of Nov. 1, 2013, the 72-year-old private pilot had flown down to Cozumel, Mexico, returning via New Orleans to Camden, Arkansas.  The amount of fuel, if any, that he took on in Cozumel and New Orleans is not known, but the FBO in Camden recalled putting 25 gallons into each side. A representative of the Hawker Beechcraft Corp. calculated that the subsequent flight from Camden to Pine Bluff would have used no more than 30 gallons of that 50 gallons, leaving the King Air with at least 20 gallons more than when it took off from Camden. The planned flight from Pine Bluff to Bentonville required a maximum of 70 gallons. The pilot apparently didn’t buy any fuel during the stop at Pine Bluff.

Until the last few minutes of the flight, radio communications were routine. The pilot contacted Little Rock Approach Control at 4:51 p.m. to request flight following to Bentonville. Radar contact was established as he climbed through 10,000 feet to his VFR cruising altitude of 16,500.  At 5:02 p.m., the flight was handed off to the Hot Springs sector of the Memphis ARTCC.  The King Air began a VFR descent at 5:21 p.m.; six minutes later, it was transferred to the Fort Smith tower while descending through 11,800 feet to a planned 6,500 feet. A potential traffic conflict required a level-off at 7,000 feet, but within three minutes both pilots reported traffic in sight and were cleared to proceed maintaining visual separation. 

The first sign of trouble came at 5:40 p.m., when the King Air pilot transmitted that he was changing his destination from Bentonville to Fayetteville because of low fuel. Within a minute he requested the distance to Fayetteville. Told it was nine nautical miles, he requested a closer airport and was vectored to Springdale, four nautical miles away at twelve o’clock. The pilot contacted Springdale tower, but 30 seconds after receiving his landing clearance advised that he’d be unable to make the field. Witnesses three and a half miles from the airport described the King Air descending with the wings level but “rocking,” and three of five described an abrupt pitch upward just before the crash. It rolled right and dropped nose-first from about 300 feet above the ground. The pilot and passenger were both killed.

Examination of the wreckage suggested that the King Air crashed about 100 yards beyond a set of power lines strung 35 to 40 feet above the ground. The wires were undamaged and there was no ground scar, suggesting a steep nose-first impact. Physical examination showed that neither engine was producing power at impact. The airspeed indicator was frozen at 78 knots, the airplane’s power-off stall speed with flaps retracted. There were no fuel stains or smell of fuel on site, and only about one quart was found in the tanks.

The panel included a fuel totalizer, which indicated that 260 gallons had been burned since it was last reset, leaving 123 gallons available. Exactly when that reset happened is not known. The NTSB said “it was reported” that the pilot didn’t like to top off the airplane, instead adding just enough fuel for the coming flight.

Anyone who’s ever forgotten to write down an ATM withdrawal knows how easy it is to let your bookkeeping drift out of whack, but the fuel totalizer is a little different. Withdrawals, measured by the fuel transducer(s), should be known pretty exactly. The problem is recording the deposits.  Either way, it’s good to balance your account now and then. At some point the King Air’s totalizer was thrown off considerably. Perhaps some fuel order was never fulfilled, or the pilot mis-keyed an entry. Creeping computational errors might also have figured in. Whatever the cause, the accident makes painfully clear that yet another pilot paid for taking off without actually knowing how much fuel was on board—whether by looking into tanks where the level would be visible, or topping it off in order to balance the books.