Qantas jet's plunge

[avandonk]

I had a control cable break due to fraying on my yaw (rudder) control. All cables should be banned until we understand cable fraying?

There are many more failures of mechanical systems that led to many deaths.

Of course I understand that there are far more people that die in larger aircraft in one 'incident'

Only rational assessment of the scientific data is the way to understand what is really happening.

I personally prefer a nice taut uninterrupted cable between my joystick and my control surfaces. When you are pulling a 6G loop and then roll 180 deg level out inverted and then push for a vertical climb and then do a stall turn and then something breaks....

Bert

[kinetic (Steve)]

Sort of Fred....
It's more along the lines of multiple redundancies Peter mentioned
several times.
Ever heard of the Gimli Glider....
Great happy ending story.
Pretty much all due to both the right pilot being in the seat and
a redundancy contingency working.
A RAT or RAM Air Turbine gave some control back to an almost
dead in the air 767 when it ran out of fuel at cruise alt.
As all of the power systems and hydraulics rely on the engines
running...this was curtains for the crew and passengers.
Except for the R.A.T that did it's job...and the experience and unique
background of the pilot.
Read it up.....great story.

Steve

[Peter Ward]

Originally Posted by Bassnut

..... Isnt there a backup option somewhere in between?, as in a seperate simple backup servo control, without automation (or cables)?, or is that mode what is ment by "switching the computer off"?.

Sort of Fred. The A330 incident wasn't actually a "failure" of the FBW system.

Several very abnormal "spikes" came from one of the Air Data/Inertial reference units (ADIRU's) ....and the flight envelope computer "protections" pitched the aeroplane when there was no physical reason to do so.

As it turned out the samplng intervals did not help things, in that the perfectly functioning ADIRU outputs were ignored (they supposed to look at each other and discard spurious signals).

I believe this has since been addessed by Honeywell.

And as I mentioned earlier..there is indeed an out...turning off all primary and secondary flight computers.

[Peter Ward]

Originally Posted by avandonk

I had a control cable break due to fraying on my yaw (rudder) control.....

Bert

Bugger

I dare say had it been the elevator you'd not be telling the tale !

[avandonk]

Yes Peter lose the elevator and you are in deep do do's. At least you can ask your 400 odd passengers to run from the back of the aircraft to the front or vice versa to simulate an elevator. I am sure you can also pump fuel to change the balance. I still maintain the tail slide had nothing to do with it. If you lose your elevator control and it is even worse in a large aicraft as the worm can get jammed due to lack of maintenance and overcycling then only thrust can start to control your attitude. Too bad if to maintain some sort of level flight to attempt a landing full thrust is required.

The most important bit of your flight is what you check on the ground. That is all your pre flight checks.

All of us are still safer in an aircraft than even crossing a busy road.

We pilots read everything we can about aircraft crashes as it may give us some ideas to not go down in the same way.

I used to work with a senior scientist who was terrified of flying. He thought that paying pilots heaps of money was a good thing as it gave them a reason for living. So that way in his own irrational logic he sort of felt safer as long as he was flying with an airline with highly overpaid pilots.

Bert

[Nesti (Mark)]

This is all starting to get pretty interesting now. How we use technology has always been critical, but the decision to place too much technology between the human operator and the machine might prove to be even more critical.

http://www.spiegel.de/international/...679980,00.html

"The controls suddenly feel completely different to the pilot," says flight expert Hüttig. The sheer complexity of the Airbus' systems makes it difficult to control in critical phases of the flight. It would be easier for pilots if they could simply switch the computer off in critical situations, as is possible on Boeing planes

Pitot tubes sometimes also fail on Boeing aircraft. When SPIEGEL contacted the American Federal Aviation Administration, the body which oversees civilian flight in the US, the FAA confirmed that there had been eight such incidents on a Boeing 777, three on a 767, and one each on a 757 and a Jumbo. Boeing is currently conducting a study on the safety effects of "high-altitude pitot icing on all models in its product line," says FAA spokeswoman Alison Duquette. The FAA did not, however, identify "any safety issues arising" during these incidents.