The Mystery of Flight 72

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This week’s blogwatch sets out to probe the mysterious in-flight incident which befell Qantas Flight 72 over WA recently.

It’s fair to say that the aviation blogoshere, comprising plane spotters, geeks, engineers and flight crews, stands by the safety record of Qantas and that old adage, "stuff happens".

Since the in-flight incident on 7 October, the Australian Transport Safety Bureau (ATSB) has commenced inquiries into the descent of the A330-300 (described affectionately by Airbus as "the long fuselage member of the family"). Early rumours that a laptop may have been to blame were quashed by a recent briefing and the ATSB has released an animated film recreating the events.

Details of the descent have been outlined with the flight data recorder showing the initial uncommanded climb above the cruise altitude of 37,000 feet was 200 feet, (previous reports suggested it was 300 feet). The first dive was 650 feet in 20 seconds, and the second dive was 400 feet in 16 seconds.

Plane spotter Philip Argy posting on the Sydney Airport message board has been analysing the early reports, and mentally reconstructing the human frappe that apparently occurred inside the cabin on QF 72:

"Imagine that you were in a lift that suddenly accelerated downwards rapidly. You’d hit your head on the ceiling of the lift. If it then reversed direction just as suddenly, you’d be slammed into the floor.

"Now think of the [aircraft]as pivoting around the fulcrum of the wings like a see-saw, so that in a sudden climb the displacement of the rear of the aircraft is like the suddenly descending lift – the inertia of the unrestrained mass of people and service carts will tend to make them rise in relation to the descending portion of the fuselage at that point.

"With CAT ["clear air turbulence"], occurring where there are no visible clouds, the sudden downward displacement of the fuselage is what makes unrestrained people contact the cabin ceiling — I’m positing the same effect in the aft of the cabin from a sudden pitch up during stable cruise.

"In the second movement sequence recorded on the FDR the 8.4 degree pitch down and descent to my mind would have more likely created almost zero G for everyone on the a/c and that would not have resulted in the injuries being so concentrated in the aft section of the cabin."

Investigations of plane accidents start with many possibilities and the initial ATSB briefing hasn’t put an end to other rumours, which included suggestions that the incident was caused by problems with the "unconventional" Airbus sidestick (the duplicate set of controls which allows the co-pilot to take over), which, unusually in the Airbus, is not mechanically linked to the main control,
or an "irregularity" in the plane’s computerised elevator control system.

Or there’s always the Crikey theory:

"Geoff Dixon has drained every last drop of blood out of the Red Rat, coupled with the complete lack of respect for the Qantas Club & Frequent Flyer member who spends more time in the air then on Earth but can’t believe they won’t upgrade them or offer another glass of shiraz as they’re left waiting for yet another delayed QF flight to leave the gate plus the issues with upgrading the Altea IT system and the engineers IR dispute have raised all sorts of issues and despite not having any qualifications in aeronautical engineering, can tell you from stuff they overheard or were told by their sister-in-law who was married to a former Qantas navigator that — well let’s just say, there are plenty of Qantas execs sneaking over to Terminal Two at Kingsford Smith and hopping on Branson Airways."

More than 40 passengers were injured on flight QF 72. Seeing an opportunity to reinforce its reputation as an airline that’s always ready to play hard ball with clients, unions or anyone else, the Red Rat has reminded any passenger seeking compensation that the seating classes are very different, so passengers will be compensated with travel vouchers at different levels.

Clearly, since being catapulted through the ceiling and then stuffed into an overhead locker is more unlike the first class flying experience than the economy experience, fist class passengers should be better compensated for the indignity. Your Bananas in Pajamas is reporting separate compensation claims are expected to cost tens of millions.

For those planning on flying soon, the nicest safety tip and reminder of the joy of flight can be found on the blog of ex-Italian Airforce fighter pilot David Cenciott.

"[The] turbulence was caused by the bad weather that QF72 encountered en route. This kind of turbulence is often linked to the jet streams that are generated by the difference of pressure between troposphere and tropopause.

"At the border between these two atmospheric areas, these streams move large masses of air that cause turbulence. The jet stream can be particularly strong and travel parallel to the ground at heights of around 11 km in a west-to-east direction (in both hemispheres because of the Coriolis acceleration). There are two major jet stream flows in both hemispheres at polar latitudes and two minor subtropical flows next to the Equator.

"Since in the Northern Hemisphere the jet streams appear at high latitudes (up to 60°–70° N), they interest many transatlantic routes: it is for this reason flights from the US to Europe last 2 hours less than flights in the opposite direction. It is connected to the jet streams, the Clear Air Turbulence [CAT], a kind of turbulence that is not associated to any cloud. Anyway, don’t worry — the flights are planned taking into consideration the possibility to encounter a jet stream and aircraft are projected to resist to any CAT. Just keep your seat belt fastened; many injuries could have been avoided and could be avoided in the future."

Wise words David. Wise words.

Although there’s never a good time for in-flight incidents, this most recent one comes soon after the delivery of the first A380 for Qantas. This was expected to improve Qantas’s image of after a bad run in the air and in the media. Qantas has been trying to get everyone excited about flying with them again — just not excited like the passengers on QF72.

But it’s not as if Qantas is the only airline having a bad time right now. Emirates have ordered more than 60 Airbus A380s but after plenty of fanfare (check the eye-candy on the Telstar Logistics blog) a fault has been discovered with the showers in First Class. The rumour is that they leak and delivery has been delayed. At newmatilda.com, we’re not aeronautical engineers but we are pretty sure water leaking on aircraft is a bad thing.

New Matilda is independent journalism at its finest. The site has been publishing intelligent coverage of Australian and international politics, media and culture since 2004.

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