Daily Telegraph: CX 744 "seconds from disaster"

[crossfire]

A colleague pointed me towards an article in the Daily Telegraph today, titled: 'Pilotless' jumbo seconds from disaster :oh:

Apparently a Cathay 747-400 did a go-around without autopilot because the disconnection warning was not noticed over the wind shear warning.

The story is online at telegraph.co.uk but you have to register to be able to read it, so I'll just quote a few lines:

"The aircraft flew uncontrolled for three minutes, veering almost 180 degrees off course toward mountains and coming within seconds of a catastrophic stall."


"Despite its steep rate of ascent, the uncommanded 240-ton aircraft was travelling at the dangerously low speed of 130 mph. It was saved from a stall, which analysts believe could have been fatal, because the left wing had dropped by 30 degrees - just enough to bring the nose down fractionally and enable a recovery. Worried air traffic controllers issued urgent instructions to bring the jet back on course."


"But this had no immediate effect, as the crew - still under the impression that the autopilot was working - were not attempting to fly manually and simply keyed the navigation commands into the lifeless machine."


Ignoring the usual sensationalist BS about a "lifeless autopilot", "uncommanded aircraft", and "catastrophic stalls", can anyone explain the real story of this incident?

... and 130 mph? smells like BS to me. I thought reporters always checked their facts :rolleyes:

I'm surprised that nobody else has posted it here yet.

Anyone got the other side of the story?

[Avman]

Hmm, unless this is new, I think it was covered some time ago. Try a search in the Fragrant Harbour forum.

This could be it: http://www.pprune.org/forums/showthread.php?s=&threadid=141635

[Five Livers]

The Telegraph story saying that the A/Pilot disengaged without the crew realising it, is pretty close to the truth as I know it,.

The published G/A from 25R at CLK requires an initial climb to 3000' and a series of right turns and stage climbs, eventually going through about 210 degrees and ending up at 4500ft.

CX 252 went around & climbed to slightly > 6000ft and the speed reduced to @118kts [VRef for 744 at 240t= 140kts]. The left wing dropped and turned the aircraft towards Lantau [& the high ground at 3100ft] and they ended up on the LEFT side of the 25 LEFT repeat LEFT Missed Approach Path. During the subsequent manouevres they an aural 'Bank Angle' warning [bank angle > 35 degrees] after they had sort of levelled off.

If the A/Pilot had been engaged AND the crew had done nothing other than hit TOGA [twice 'cos it's Windshear], they would have gone up like a rocket with Max Thrust to 3000ft maintaining roughly 250 track and disappeared at 3000ft until they hit Vne.

The fact that they didn't points pretty conclusively to the A/Pilot falling out at some stage before 3000ft, unnoticed by the crew.

Again the Telegraph seem on the track when they speculate that the Windshear aural may have drowned the A/Pilot wailer

[Stratocaster]

Do we know what triggered the "wake-up call" for the crew ? Apparently ATC tried to warn them but they didn't take action immediately.

[ManaAdaSystem]

Autopilot disconnect aural warning has a low priority when it happens at the same time as other warnings. WS and GPWS warnings will "cancel" the autopilot disconnect warning should they take place at the same time.
Easy to forget, easy to overlook, and hello Murphy!

[747FOCAL]

At flaps 10 and 130 mph the 747 at any weight would be a rock.

[411A]

Why are we not surprised at this incident?

And just think, just a couple of years ago they wanted extra $ in the pay packet, because they are 'so professional' and 'we deserve more'.

No wonder 49+ went bye-bye.

[christn]

I suspect that the reason you are aware of such incidents and are able to make such childish comments is due to the Professionalism, maturity and openness of the company and crews involved.

What a shame you have nothing useful to add to the discussion!

[UNCTUOUS]

<<Autopilot disconnect aural warning has a low priority >>

Maybe so but surely you don't get any warning at all if the autopilot is accidentally/inadvertently disconnected NORMALLY.

Not in the airplanes that I fly/flew....

In the ruff n tumble of a sudden go-round would it be possible for some press-button-itis to have normally disconnected the autopilot? And having done that, it may follow that the individual wot did the dirty deed may not necessarily be aware that he had.

As Bart Simpson said: "I didn't do it". Sometimes things happen and you cannot recall having been the conscious culprit.......

AND,
Are go-rounds "de rigeur" for a precautionary wind-shear alert?

[cactusbusdrvr]

What was the missed approach altitude setting on the MCP? I don't know anything about the 74 Autoflight system but on the 757 if you don't set a go around altitude the autoflight system drops out once you go above what is set on the MCP.

Sounds like there would be a change of underwear after this one.

[Wizofoz]

UNCTIOUS,

On all Boeing aircraft the AP dissconect aural and visual warning is triggered by one push of the AP dissconect switch, or if the AP dissconnects for any othe reason. A second push on the switch silences the warning.

[autoflight]

CX not the only ones. In the 1980s a north-west African 747SP stalled at 4000ft over Kai Tac with the King on board.