If it had crashed on February 20, 2014 when it was 47 kilometres WSW of Sydney Airport, a Virgin Australia ATR 72 would have become the worst airline disaster in Australian history.
A second ATSB interim report released today into the state of that 68 passenger aircraft, which was approaching the end of its flight from Canberra, says the inadvertent actions of its two pilots could have catastrophically damaged its airframe faster than they could have recognized and corrected their mistakes.
Over that part of western Sydney the flight could have plunged onto a major motorway, or a retail centre or housing estate if not open ground.
Wherever it might have come down, it would have been instant carnage, all over the evening news, all because its because two pilots accidentally applied opposite pitch inputs to raise or lower the nose of the aircraft, with sufficient force to break critical parts of its tail control surfaces.
But the Virgin ATR not only safely completed its flight, albeit with serious leg injury to a cabin attendant, but went on to fly up 13 more sectors over five days before it was grounded in a manifestly unairworthy state at Albury Wodonga.
That astonishing lapse of oversight and maintenance procedures is the subject of the on going inquiry by the ATSB.
Today’s second interim report says that the turbo-prop was at risk of a catastrophic failure of its airframe from the moment the initial incident occurred. It says tests showed that the
- vertical load on the horizontal stabiliser was exceeded
- vertical load on the wing was reached
- bending moment on the wing was exceeded
- engine mounts were exceeded.
- the ultimate load, in terms of the asymmetric moment on the horizontal stabiliser, was exceeded.
The ATSB says it acted today to release an interim report tightly focused on the ‘pitch disconnect event’ because “a safety issue has been identified that, in the interests of safety, needs to be brought to the attention of the industry before the investigation is completed.”
The ATSB is surely referring to the world wide users of this turbo-prop, since the situation with this particular aircraft has been front of mind for Virgin Australia since the first competent investigation of the damaged state of the aircraft was made shortly after it was declared inoperable at Albury airport about six or seven days after the initial incident.
This ATSB report needs to be read in full to understand the gravity of that first incident. To do that it is necessary to go down to the bottom of the page and open the two blue + signs which hide its ‘safety analysis and finding’ and the ‘safety issue and actions’ sections.
Virgin Australia issued this statement this afternoon.
Safety is Virgin Australia’s number one priority and it is important to note that this aircraft landed safely during this event. Following this incident we immediately implemented a number of risk controls over and above the manufacturer’s recommendations. The aircraft manufacturer also conducted a full review of our ATR-72 fleet which found it was safe to continue operations. This investigation is ongoing and we will comment further upon the release of the final report.
An earlier Plane Talking report encompassing both the initial incident and the deterioration of the airliner to the state where it could not continue to fly after a landing at Albury can be read here.