British Airways Flight 9 The Institution of Mechanical Engineers report entitled "Volcanic Ash: To Fly or Not to Fly? reports that the prediction of "ash movement and dispersal has become more sophisticated over the years. In the UK, the Met Office uses Numerical Atmospheric-dispersion Modeling Environment (NAME), computer model, developed after the Chernobyl accident in 1986." (2010, p.3) This model is reported to have tracked various atmospheric dispersion events and to have as its purpose the prediction of "how far and how concentrated, emitted particles will be dispersed, using a number of factors, such as wind, rainfall and particle size…" (Institution of Mechanical Engineers, 2010, p.3) On June 24, 1982 British Airways 747-200, Flight 9 near Jakarta Indonesia ran into trouble when the crew accidentally flew into a volcanic ash cloud from Mount Galunggung in west Java, Indonesia. The ash caused severe damage to all four engines and the aircraft lost its flying power briefly. The crew was however able to restart the engines once the plane glided out of the dust cloud. The crew was able to make an uneventful landing in Jakarta with none of the 15-crew members or 247 passengers being injured.

I. Report of Eric Moody

Eric Moody writes that the airline pilot's job in the earlier days of civil aviation was one "in which character, skills, and a dogged ability to stick to the task under extreme pressure, were tested on an almost daily basis. Weather forecasting was rudimentary; navigation was based on fleeting glimpses of railway lines thorough ragged cloud and accurate landings on an ability to discern a dim line of gooseneck flares. These aircraft were subject to frequent technical failure and the engines had to be nursed with the sensitivity of old stagecoach drivers used in handling an inexperienced team of four. Those who learned their trade during the war came through an even more deadly and unforgiving school." (Moody, 1986, p.1)

However, Moody states that pilots in the modern generation "sit in air-conditioned comfort, with reliable engines, navigating errors measured in yards rather than miles on aircraft which can handle themselves, smoothly and accurately, in almost impenetrable fog." (1986, p.1) Moody writes that his generation of pilots is the first "who may go through a whole career without having a genuine emergency; many pilots have completed fifteen years flying without having suffered an engine failure." (1986, p.1)

II. BA Flight 009

British Airways Flight 009 was carrying 247 passengers along with 91,000 kg of fuel on the flight to Perth. The night was "moonless, but clear and the flying conditions were smooth." (Moody, 1986, p.1) The weather forecast was good and the expectations of the crew was for an "uneventful flight lasting 5 hours." (Moody, 1986, p.1) The flight had eaten their meal and settled into the cruise at 37,000 feet. Moody is reported to have taken "a quick look at the area ahead of the aircraft with the weather radar and picked up nothing more interesting than returns from the surface of the sea. He made his way aft and found that the crew toilet was occupied. He descended the stairs to the first class area and started a conversation with the forward purser Sarah Delane-Lea. Almost immediately he was called to the flight deck by Fiona Wright the Stewardess I." (Moody, 1986, p.1)

As Moody climbed the stairs it is reported that ne noticed that "puffs of smoke [were] billowing out from the vents at floor level and a smell which he described as 'acrid or ionized electrical' such as one finds near sparks from electrical machinery." (Moody, 1986, p.1) When Moody entered the flight deck, he found the windscreens on fire "with what appeared to e the most intense display of St. Elmo's fire he had ever experienced." (Moody, 1986, p.1) Moody is reported to have then strapped himself into his seat and to have looked at the weather radar again." (1986, p.1)

In Moody's absence in the flight cabin, it is reported that other two crew members "had put on the seat belt signs and the engine igniters." (Moody, 1986, p.1) It is reported that a belief exists that the "slow build-up of danger ensured that they [the crew] were not plunged instantly into an extreme situation. They became more alert and concentrated as the incident became more complex and at no time lost control of their reasoning processes. They were soon forced to face the full consequences of their problem by the voice of the Flight Engineer."...

This would have caused a failure of the co-pilot's instrumentation and much of the cockpit lighting. Yet the instrumentation all appeared to work and the auto-pilot remained in control." (Moody, 1986, p.1) The engine displays are reported as a mix of Smiths and General Electric with some of the freezing when power was lost and some with needles dropping off the scale. In addition, amber lights indicated that the engines had exceeded their maximum turbine gas temperatures. The Flight Engineer suggested that they shut off the engines and Moody put the auto-pilot into a "gentle descent" and instructed the co-pilot to "put out a Mayday." (Moody, 1986, p.1)
II. Processes, Intuition and Decisions of the Flight Crew

The crew attempt to relight the engines 1, 2 and 3 and attempt to relight number 4 engine once the fire handle had been pulled when the fire drill was carried out. It is reported that the cabin pressure warning horn sounded as the plane climbed through 10,000 feet. When the removed their oxygen masks one of the pilots masks fell apart when pulled form stowage. Moody had to decide at this point whether to continue the plane's descent or to have the co-pilot "suffer the effects of anoxia and Moody went ahead with an emergency descent. (1986, p.2)

Moody did decide however, not to extend the landing gear although the manual instructed otherwise because this presented the possibility that he might have to "ditch the aircraft with gear extended should it prove impossible to retract them." (1986, p.2) Hindsight shows that "it is now obvious that during a gear extension the hydraulic power from windmilling engines might not be powerful enough to move the gear and the fling controls at the same time." (Moody, 1986, p.2) The aircraft had been turned back towards Jakarta and that with a safety height of 10,500 feet in that area that they would turn the plan out to sea when the aircraft reached 12,000 feet. When the aircraft reached 20,000 feet, it is reported that Moody "retracted the flight spoilers and reduced the rate of descent." (Moody, 1986, p.2)

By that time, the co-pilot had managed to put his oxygen mask back together reported to be a "test of intelligence and manual dexterity while under extreme pressure…" (Moody, 1986, p.2) It was at the time that the captain announced to the passengers as follows:

"Good evening ladies and gentlemen. This is your Captain speaking. We have a small problem. All four engines have stopped. We are all doing our damndest to get them going again. I trust you are not in too much distress." (Moody, 1986, p.2)

III. The Engines Restart

Just as Moody had began to consider "the awesome consequences of attempting a deadstick touchdown on the sea a night it is reported that his thought were interrupted "by sounds of jubilation from the other two crew members as number 4 engine started." (1986, p.2) This is reported as the engine which had first run down and the successes amply repaid Eric's gamble in trying to start it. The other three engines started an almost interminable 90 second later. They were at 12,000 feet." (Moody, 1986, p.2) The flight crew is reported to have "immediately requested a climb to a height which gave them ore clearance over the high ground ahead of them and asked for a clearance to Jakarta. They climbed to 15,000 feet and at about this height there was a resumption of the St. Elmo's Fire." (Moody, 1986, p.2) Number 2 engine surged continually when the throttles were pulled back and the aircraft was shut down. Eric suspected that the St. Elmo's Fire, above 15,000 feet was connected with the engine problems somehow and he decided to get away from "the strange atmospheric effects but resolved to leave the throttles in their present position and to control the aircraft speed and the descent by the use of speedbrakes, flaps and undercarriage. This required a leap of the imagination as up till then they had a strong suspicion that the engines had failed because of an oversight or an error, by the crew." (Moody, 1986, p.3) The aircraft was cleared to Jakarta Airport where the weather was fine with calm…