Qantas A380 makes a successful emergency landing

[Ian Warren]

Found this, reply #266 - one engine stuck at flight idle would be a lot easier to handle for a landing, you'd just have to hope that you never lose FADEC just after takeoff !

QUOTE

Regarding #1 Engine continuing to run at the last commanded thrust based on loss of command, I don't believe that is the case, or at least maybe it differs for the control systems of different aircraft/engine combinations. I've experienced a CFM engine return to idle power due to loss of thrust command. The FADEC sends out a signal to an RVDT at the thrust lever in the cockpit, and the return signal (dependent on the position of thrust lever) is split into two parts which have to match each other within 2%. If they are not within 2%, signals from the channel not in command will be used, so long as they are within 2%. If the signals from both channels are out of range, then the FADEC commands the engine to idle. If the Aircraft on Ground signal is not available to the FADEC (ie the wire has been severed) then idle speed will be at flight idle rather than ground idle even when the aircraft is on the ground, for failsafe reasons.[/quote]

Also here is reply # 242, about the engine continuing to go until it runs out of fuel - You'd think that if nothing else there would be a physical manual shutoff somewhere that crash crews could get to, but where would you put it ? Would you want to creep up on a Trent 900 to open a panel on the side and turn the tap off ?

QUOTE

A few posts mentioned the Etihad A340 in Toulouse.
In that case, engines #1 and #2 struck the blast wall, but both engines #3 and #4 kept running.
Engine #4 was indeed "drowned" after nearly three hours, using water and foam, but engine #3 kept running until the fuel was exhausted, because the engine was too close to the blast wall to get enough water and foam into the engine.[/quote]

Chairman

Sim-holic

 

Joined: Wed Feb 13, 2008 8:07 pm

Posts: 912

Top

[Chairman]

Meanwhile, in a pleasant contrast to the sensationalist reporting everyone else is pumping, here is CNN's story on it ...

http://www.flightpath.co.nz/cnn_a380_headline.jpg


Gary

[Ian Warren]

Nothing like a brand new Airbus , aye .. Guy Fawkes in the next day or so , POP ! , BANG ! .. ya then get the big one you want to play with , then FIZZEL ! Poof out it gos

[Chairman]

http://www.aviationweek.com/aw/generic/sto...mp;channel=comm

EASA Orders New Trent 900 Inspections

Nov 11, 2010

By Robert Wall wall@aviationweek.com
LONDON

The European Aviation Safety Agency (EASA) issued an airworthiness directive (AD) effective Nov. 10 mandating new inspection requirements for Rolls-Royce Trent 900 engines powering Airbus A380s. The action was taken after an uncontained engine failure on a Trent 900 powering a Qantas A380 on Nov. 4. Since then, several oil problems on Trent 900s have been found by operators.

The EASA directive states that “An uncontained engine failure has recently occurred on a Rolls-Royce Trent 900 involving release of high energy debris and leading to damage to the aeroplane.

“Analysis of the preliminary elements from the incident investigation shows that an oil fire in the HP/IP [high pressure/intermediate pressure] structure cavity may have caused the failure of the Intermediate Pressure Turbine (IPT) Disc.

“This condition, if not detected, could ultimately result in uncontained engine failure potentially leading to damage to the aeroplane and hazards to persons or property on the ground.

“For the reasons described above and pending conclusion of the incident investigation, this AD requires repetitive inspections of the Low Pressure Turbine (LPT) stage 1 blades and case drain, HP/IP structure air buffer cavity and oil service tubes in order to detect any abnormal oil leakage, and if any discrepancy is found, to prohibit further engine operation.

“The requirements of this AD are considered as interim action. If, as a result of the on-going incident investigation, a terminating action is later identified, further mandatory actions might be considered.â€￾

As a result, the regulator is requiring operators to carry out extended ground idle runs, inspections of the low-pressure turbine stage 1 blades and case drain, and inspection of the high pressure and intermediate pressure structure air buffer cavity and oil service tubes.

If a problem is found, “any further engine operation is prohibited,â€￾ EASA says.

For on-wing engines, inspections are required within 10 flight cycles of the AD taking effect, and then at intervals of no more than 20 flight cycles. For in-shop powerplants, the inspection requirement is after an engine test procedure and before the next flight.

In addition to Qantas, which has its A380s grounded, Singapore and Lufthansa are changing some of their Trent 900s, although the latter says it is unrelated to the Qantas problem.

[Ian Warren]

Go from 25 to 30 per cent off the aircraft cost is the engine , Rolls Royce is going to want to get this one right only for the reputation .

[Charl]

140 years of experience and over 71,000 flight hrs – a significant factor in the successful outcome of the incident.
Here's an interview with Captain David Evans, Senior Check Captain on that flight.
http://www.aerosocietychannel.com/aerospac...om-the-cockpit/
This was a really close call...

[Ian Warren]

NOW that,s good listening , No.1 engine running 5 hours on the ground because they could shut it down , so fire crew drowned it , very lucky with the fuel .

One thing Captain David Evans mentioned was they tried to simulate it , this is one thing they also tried after the United Airlines DC-10 crash at Sioux City in 1989 - they also could not simulate the emergency , only the thinking outside the square that saved many .

[Charl]

It's the human element you need in situations like this...
Crew elected to ignore/skip certain ECAM advisories because there were conflicting messages.
And they convinced the fire crews to approach an aircraft before engine shut-down - breach of rules.

Think about the scenario with a crew that panicked, and maybe deployed the emergency slides onto a fuel-soaked runway with brakes glowing...

I have utmost respect for the top pilots - they have a way of precisely following the rules, exactly up to the point where they impinge on good airmanship.