Safety Experts Find Pilots Reluctant To Abort Landings
Airline pilots occasionally must decide whether to abort a landing because the approach isn't quite right, as with Asiana Airlines Flight 214, and safety experts are studying the industry reluctance to circle an airport and try again.
In the Asiana crash, the pilot's decision seconds before impact to try a "go-around" came too late and the plane crashed Saturday at San Francisco International Airport, killing two passengers and injuring more than 160.
More often, a mistake in the landing means a "runway excursion" where the plane runs off the end or side of a runway with little or no injuries. But safety experts have found pilots reluctant to abandon landings, so they are studying whether there would be fewer accidents if they performed more go-arounds.
"It's not that they're making the wrong decision necessarily, it's how they get led down that path," said Rudy Quevedo, director of global programs at the Flight Safety Foundation, which studies aviation accidents. "One of the biggest things that we see is that the pilots don't feel a threat -- they feel they can recover."
The foundation reviewed 16 years of accidents worldwide and found that one-third involved runway excursions. In studying the biggest risks for excursions, the foundation surveyed 2,500 pilots worldwide and discovered that a plane approaching a landing in an "unstable" way occurs in 3.5% to 4% of all approaches, according to a report released in February.
With more than 20,000 flights each day in the USA, the problems quickly add up. A stable approach means the plane is on the right path at the right height and speed, with the flaps and landing gear in the right positions. Unstable means one or more of those elements may be off.
In the Asiana crash, investigators found the plane was going much slower than the 137 knots intended at landing; it was at 103 knots three seconds before impact. Crash investigators said the flight-data recorder found pilots began increasing the throttle eight seconds before impact and called for a go-around 1.5 seconds before impact.
Major airlines have rules calling for pilots to perform go-arounds if their descents are unstable when they reach 500 feet above the ground on a clear day or 1,000 feet off the ground when pilots are flying with instruments.
But the foundation discovered that pilots perform go-arounds in only about 3% of their unstable approaches. The studies are continuing, but the foundation found reasons for the reluctance include a pilot's pride in completing the job, reduced fuel at destinations and the lack of attention on unstable approaches when planes land safely.
"It's not a pilot problem and it's not a management problem -- it's really an industry problem," Quevedo said. "We need to understand why."
John Cox, a former commercial pilot and president of Safety Operating Systems consulting firm, said more study is needed.
"My speculation is that using experience, (pilots) recognize that they're not very far out and they'll be within the stable criteria within a few seconds," Cox said. "It is very much worth a deeper look."
One aspect of the studies is whether a dramatic increase in the number of go-arounds would improve safety.
"What could be the risk?" Quevedo asked. "Could we make something worse, in effect, or would it be better?"
Earlier this month, the National Transportation Safety Board urged the Federal Aviation Administration to change its rules so that planes aren't placed on collision courses when one plane is performing a go-around and another plane is either taking off or landing on another runway.
The NTSB noticed five incidents in recent years - including three in Las Vegas - where planes got too close together when one performed a go-around and another plane was either taking off or landing on another runway.
Nobody was injured in the incidents and in several cases the pilots didn't even see each other.
The FAA said in a statement that the agency "thoroughly investigated the incidents and took aggressive steps to address the causes," and that the agency would respond formally to the NTSB.
The Asiana crash is expected to focus more attention on go-arounds.
"I think this Asiana accident potentially has the possibility of being one of those catalysts for increased training on go-around and accepting a go-around at an even earlier time," Cox said.
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