The latest gripping read about a Qantas flight, the preliminary report into the 7 October double dive by QF 72 and its emergency landing at Learmonth in WA, shows that a lot more went wrong with the Airbus A330 than previously disclosed.
The jet’s captain was mostly on his own for the early part of the control crisis, after sending the second officer back into the cabin to get the first officer who was taking a scheduled rest break.
Both the captain and first officer had to deal with eight serious failings in the air data and inertial reference system, not just the erroneous angle of attack values that were fooling the flight control system.
The cockpit was filled with the sound of what were false stall warning alarms and other “master cautions”. The fault messages display in the cockpit began scrolling too fast for the pilots to read.
It all sounds a bit like Microsoft Office gone mad on a bad day, but this was a jet at 37,000 feet with 315 people on board, 74 of whom were to be injured, nine of them seriously.
The report is illustrated with the damage some of their heads did to the overhead lockers when flung upwards from the seats in an abrupt negative-G upset.
The Australian Transport Safety Bureau report will be a must read for every airline everywhere flying modern computer intensive passenger jets.
It is probably the most important inquiry the ATSB has ever begun, and the mystery remains largely substantially unsolved at this early stage. This preliminary report does however finger the US avionics maker Northrop-Grumman as a party of interest, because it made the inertial reference system unit that went mad and put QF 72 from Singapore to Perth in grave peril.
Airbus has already dictated a significantly changed operating procedure for dealing with “upsets” like this one.
The ATSB also shared the investigative role in a somewhat similar incident with a Malaysia Airlines 777 on 1 August 2005 also over WA. However in that incident the jet kept trying to climb rather than dive out of control, and while it also involved a fault that fed false data to the flight control system of the Boeing, it was caused by an inertial reference data unit made by a different avionics firm.
These type of systems are found in every large jet built since about 1989 and some dating back to the early 80s.
This preliminary report casts doubts on popular theories that a passenger operated computer or even electromagnetic interference from the top secret Harold E Holt US “spy base” near the QF 72 flight path could have caused the accident.
The base, which keeps watch on Russian nuclear missile carrying submarines, uses ultra long wavelength signals to find them hundreds of metres under water.
However the ATSB says it is still gathering and examining whatever information it can about such remotely possible scenarios.
This factual phase of the inquiry has found no evidence that Qantas or its pilots did anything to cause this incident.
On any reading of this report, the actions of the pilots should remind the incoming management at Qantas that excellence in flight standards is a priceless asset that must never be compromised.