Former test pilot recalls flying through volcanic ash


PILOT'S EXPERIENCE:A FORMER US test pilot who witnessed first hand the effects that flying into volcano ash has on jet engines said the aviation authorities had no choice but to shut down European airspace.

Bernie “Topgold” Goldbach, now a lecturer on the multimedia programme at Tipperary Institute, said flying into the volcanic ash cloud left by the giant Mount St Helen’s eruption in 1980 had been a scary experience.

Mr Goldbach said he was sitting in the right seat of a giant military cargo plane the C-141 Starlifter on May 20th, 1980, when it approached the leading edge of Mount St Helen’s volcanic ash cloud, and the cloud extended higher than several weather experts had predicted.

“I still remember the uneasy feeling I got when Hal the aircraft commander throttled back at level off because the number four engine burped and shot a 10-ft plume of flame out its front compressor.

“The whole aircraft shuddered, and our main air conditioning pack started a wild temperature fluctuation.”

Two of the aircraft’s engines had to be repaired at a cost of more than €500,000 in today’s money, and he made a “memo to self” to make sure he avoided volcanic ash when flying in the future.

“The ash attaches to the turbine section of an aircraft engine. It starts to cause all sorts of problems. It changes the airflow characteristics, reduces thrust and causes backblow. It blew a combusting mixture back through the front of the engine. It can lead to engine trouble.”

He said ash could cause a catastrophic engine failure. Alternatively, it could cause huge damage to aircraft engines which are more than a third of the cost of a plane.

“Aircraft are not designed for anything other than air going through the engines,” he said.

The latest ash plume was such that planes flying through it increased the chances of an accident.

“It was a safety decision, not just a commercial decision,” he explained.

“It is going to cost airlines a lot of money, but it would have cost them even more money if they crashed.”