Qantas B744 Total electrical failure?
 

QANTAS faced a potential disaster on Monday when a jumbo jet en route from London lost all main electrical power and was forced to land on battery back-up.

Flight QF2 with 344 passengers on board was about 15 minutes from Bangkok when the highly unusual failure took place and a back-up system kicked in.

With the batteries providing power for up to an hour, aviation sources said the failure would have been a disaster if it had occurred further out to sea.

"If this had happened over the ocean in the middle of the night, it would probably have crashed," an experienced 747 pilot told The Australian last night.

The near-disaster came nine years after a Qantas 747 aquaplaned off the end of the runway at Bangkok airport, crashing through navigational equipment and finishing up across a perimeter road 220m away.

The crash, Qantas's worst in 40 years, caused about $100million in damage.

Qantas chief pilot Chris Manning and the Australian Transport Safety Bureau yesterday confirmed the incident took place as the plane returned from London. "The back-up system was activated and the aircraft landed safely," Captain Manning said.

"Qantas reported the incident to Boeing, the ATSB and Civil Aviation Safety Authority and is also conducting its own thorough investigation.

"The aircraft is currently being repaired and assessed."

ATSB deputy director of aviation safety investigation Julian Walsh said investigators had been advised of the failure and had asked for flight data and cockpit voice recorders to be quarantined.

He said the ATSB was liaising with Thai authorities about who should lead the investigation. It was too early to say what had happened, he said, but he agreed the failure was "unusual".

"Obviously Qantas, Boeing and ourselves are keen to get to the bottom of it," he said.

"The information I have at the moment is that it was a total power failure."

Mr Walsh said he understood the aircraft's systems went into a degraded mode under standby power to reduce the drain on the batteries. The 747-400 has four generators, one on each engine, plus two generators on the auxiliary power unit that sources said could be linked to the main system in an emergency.

A Qantas engineer familiar with the the 747-400's electrical systems said the failure was unheard of.

He said the battery back-up and standby inverter would supply power for up to an hour.

"It's pretty dramatic if they've lost all generation systems," hesaid.

The engineer agreed the APU generators could be used in an emergency but noted that would depend on the fault that had led to the loss of power.

Another 747-400 pilot said he was aware of two other instances when the electrical systems had failed and the aircraft went to the battery back-up. "It has happened before and the aeroplane can quite comfortably cope with it for a limited period of time," he said.

Australian and International Pilots Association president Ian Woods was also surprised that the plane had lost all power. "The pilots have done a good job in dealing with a highly unusual event," he said.

The source is The Australian for 9th January 2008:


http://www.theaustralian.news.com.au...3-2702,00.html

I am told VH-OJM, last C check carried out in Sydney.:suspect:

Sounds like the "experienced 747 pilot" isn't as experienced as he makes out.:suspect:

On second thoughts, a better way for him to describe the scenario would be "If this had happened over the ocean in the middle of the night, I would probably have crashed". Idiot.

I think he may have been alluding to the fact that if he was out at sea, middle of the night, he would have had to fly for longer than the standby power system supplies battery power to the standby instruments.

When the juice has dried up, I think it would be a little challenging flying at night with only a magnetic compass, no A/H, and basic pressure altimiter and airspeed. No comms, or nav aids, foreign country. Not impossible, but pretty difficult.

Weekend flyer here - no opinions, only questions, so pls treat accordingly. Gald someone else is questioning this so called "experience pilot". Out if interest, if it had happened further out and the back up batteries or bus had failed but all engines were still running, plane can still be controlled, right? Hyrd. units would be pressurised by the engines and gear could still be lowered also - is that correct? What would the crew have available to them? Analogue compass only? Could the APU be started if relevant altitude was reached, and even if it could, would the crew even know their altitude (could ATC provide an accurate reading?)? Are there SOPs covering such an event? Pretty amazing set of circumstances whatever the cause. Thanks.

I think things look pretty dire for anyone at night time IFR when all battery power has gone. Someone holding the torch up to illuminate what standby instrumentation is left - no airtifical horizon, no comms - no body to talk to, no nav aids - just a compass.


Think I would be asking the cabin crew to get a pax to see if they had a portable GPS on them.

I understand the APU of a 744 is not designed to run inflight.

Anyone know what happens to the windows when they lose electrical power/heating for an extended period of time (i dont know - just a question here)

It runs in flight it just cant be started in flight. An inconvenient difference in this case!

Doesn't the 744 have a RAT?

I don't know myself, but according to a thread on this same suject in the D+G Forums, NO it doesn't.

Also a lot of other info over there. :ok:

B747-400 Rat
 

no, B747 does not have a RAT

and if you are thinking that was an easy job flyig on batteries please let me write down here some of the more important (ad my advise)inoperative systems: (in order of less importance )
sped Brake Auto/single source ILS/cabin ALT auto/fuel pressure 4-1/AC bus all/yaw damp/Packs 3,2,1,/fuel pumps aft/fw 2,3,/heat probes including TAT and AOA/ Ground p[orximity protection/trasponder/FMC right/ IRS AC all/

cheers

The 747 does have a RAT (Ram Air Turbine), actually two of them, they are called Engine 3 and Engine 4.:}

As to what caused this failure?
A source claims it was a blocked drain under one of the gally's that caused water to short out an electronics rack that caused the generators to fail.
I'm sure the full and proper cause will be revealed.
It would be a real shame though ,if this was due to substandard outsourced maintanence wouldn't it!
Another case of Profitability before Safety before Schedule?:)

"It would be a real shame though ,if this was due to substandard outsourced maintanence wouldn't "

Seems it may not have been outsourced at all - post on the D&G forum suggests it was local.

"Seems it may not have been outsourced at all - post on the D&G forum suggests it was local."

Reportedly it was the last aircraft to have gone through major maintainance in Sydney... Why am I not surprised... The people doing the work were probably about to lose their jobs (and they knew it). Their focus probably lay elsewhere.

The decay continues...

Rgds.
NSEU (former "expert".. now "jack of all trades.. master of none")

Thread on this in D&G
 

This is all getting a good run over in D&G.

Mods, any chance of a merge?

What difference would it make if the plane was flying at night over the ocean rather than any other time of the day?

Muppett99,

Loss of artificial horizon - I suspect it might be harder to see the real horizon at night, over the drink, at FL410 if there's no moon or unfavourable WX. So you might find yourself in a nicely balanced, imperceptible attitude change which suddenly gets very messy and difficult to recover from.

Hmmm, down to ships battery power, not good.

It will be remembered by some that one airline, which pioneered many (but certainly not all) long overwater routes (Atlantic mostly)...TWA, had extra ships batteries fitted to cater for this very same potential problem.
PanAmerican (most aircraft)...likewise.

Never ever ever depart with insufficient ships battery backup power.

Note: Even TWA Constellations had extra ships batteries fitted....ditto their B707's, L1011's.

As I read it, when the batteries run out, you are dead meat. The only way to survive this scenario, as I understand it, would be to switch off the batteries to preserve the basic standby instruments until within range of an airfield. That would require a good visual horizon and a lot of seat of the pants skill.
Didn't the Americans lose a B52 with a similar problem during one of the Gulf wars?

Pan Am lost a 727 that way. GENs went out FE switched off BAT (instead of the GALLEY PWR switch).

All dead.

747-400 - No APU or Ram Air Turbine Power? Just Battery?
 

On a 737-800 This is the procedure and events that occur in event of loss of Gen 1 and Gen 2 in flight on a 737-800:

1) STBY AC BUS and STBY DC BUS automatically switch to their back-up source upon loss of both
engine driven generators. The STANDBY PWR OFF amber light should not be illuminated!
If you see this light illuminated, the first check-list to be started [before the LOSS OF BOTH
ENGINE DRIVEN GENERATORS] is the STANDBY POWER OFF NNC (non normal check list)

2) Bus Transfer switch OFF

3) Electrical Hydraulic pump switches OFF

4) APU select Start & On Busses

5) Bus Transfer switch AUTO

3) Electrical Hydraulic pump switches ON (one at a time)

5) Max APU Start Alt FL250.

6) Declare MAY DAY, if loss of only 1 generator declare PAN PAN.

Looking at the news tonight you would think that no APU or RAM air was available for a 747-400 - is this the case? :confused:

"The only way to survive this scenario, as I understand it, would be to switch off the batteries to preserve the basic standby instruments until within range of an airfield. "

If you switched off the battery on a 744 (whilst down to Battery/Standby Power), you would lose your standby attitude indicator...

The next best thing would be to pull circuit breakers for selected systems (e.g. Do you really need a FMC, more than one IRU, cockpit dome lights, etc...)

I guess you could pull and push in cb's as required (think twice about pulling the IRU DC CB, though )

"Looking at the news tonight you would think that no APU or RAM air was available for a 747-400 - is this the case?"

Can't start the APU in flight on a 747-400 (airplane logic prevents it). On an aviation forum in the dim dark past, someone said they could do it by pulling certain circuit breakers... but I never got around to proving it (using wiring diagrams). Not sure what RAM air is on a 747-400.. unless we are talking about pack cooling??? Not sure how this would save the day, though :}

Rgds
NSEU

"Looking at the news tonight you would think that no APU or RAM air was available for a 747-400 - is this the case?"

Correct.

No RAT (Ram Air Turbine)
APU not to be started in flight.


Rgds

N

APU not to be started in flight.

747-400 APU CAN'T be started in flight... NOT shouldn't, musn't, not to be.....

Well, perhaps it should be made able to be.


The main issue is attitude. Then navigation Then some sort of communication with ATC.

I've beat a drum on this for years, but a turn and slip with its own battery could have saved several disasters over the years. The first one that I was involved with was the British Eagle Viscount. Total electrical failure: Total loss.

That particular captain loved a challenge, but even he broke the outer wings off doing a cloud break. They didn't quite make it over the top of an autobahn embankment.

A t&S the size of a flashlight, could have saved the day. These days a spare totally independent GPS is obvious. These life saving bits of kit would take up less space than a shaver kit.

I don't know if any GPS will show turn information quickly enough to dispense with the T&S instrument.

I understand some instruments have a back-up battery inside them, but to make long term demands on such a small battery with the load taken by an artificial horizon would be expecting too much.

I just read somewhere that the cause of the initial problem was water getting into the generators...now I don't know how all 4 could be lost...but, like murphy said: if it can happen, it will happen.

I hope that we take this situation seriously. It is possible to lose everything...to be down to battery with 45 minutes of power...time to think how to use that time. Over the USA, land at the first available proper airport.

BUT over the ocean, at night, hours from landfall...ouch.

if in the clear, I would get out a mayday, request an intercept and escort and advise powering down and an ETA for the next radio contact. Certainly there are so many concerns and potential scenarios.

There was a delta 767 that had the same problem, crew landed ok. AND YES, the RAT didn't work! 747 doesn't have the RAT to being with.

if NOT in the clear, you have to keep the gyro working somehow.

*(I suppose someone could use the cat system...joke here)

APU
 

the 747 boys indicate that you CAN'T start the APU in flight.

fine.

CAN you start the APU on the ground and leave it running throughout the flight to supply electrics? air?

just wondering.

Qantas Statement on QF2
Sydney, 09 January 2008
Qantas said today the B747-400 aircraft that lost electrical power on descent into Bangkok on 7 January was now back in normal operation.
Qantas Executive General Manager John Borghetti said the pilots had handled this unusual situation in line with their training.
Mr Borghetti said the incident was triggered by water entering the generator control unit, which caused loss of power. The aircraft had automatically reverted to standby power.
"The aircraft was subjected to stringent inspections and testing in Bangkok before being cleared to fly," he said.

"As is normal practice, we are conducting our own investigation as well as working with Boeing, the ATSB and CASA, on their investigations. A more detailed report on the incident will be released by the ATSB in due course.
"As a precaution, Qantas has inspected its entire B747-400 fleet and all of these aircraft have been cleared to fly."
Mr Borghetti said that Boeing, in line with normal practice, would notify all airlines operating B747-400s of what had occurred.

Issued by Qantas Corporate Communication (Q3709)

If there is a hughe amonut of water killing the AC Power distribution an APU wouldn't be of great help either.....

So then even if you had the APU up and Running, you would be in the same situation except instead of having four Generaters offline, you would have five generaters...offline.

I believe that the drip trays located in the fwd MEC failed ( maybe the trays were missing altogether) this should have prevented any water leaking this time from the First Class galley from getting into the electrical system.
Some of the components on those rack are many of the Control units including the Generators Control Units GCUs that would have tripped off line

Boeing believe that there was no requirements for the 400 to be started a APU in flight.
Unlike the B747 classic which some had in-flight start capabilities these had a special air scoop fitted on the APU door,

United departing LAX...

Quote:
I understand the APU of a 744 is not designed to run inflight.

It runs in flight it just cant be started in flight. An inconvenient difference in this case!




Worth a shot thou if last resort!!!!!!

The B747-400 does not have a RAT(ram air turbine).
The APU is available in flight up to 20,000ft.
It cannot be started in flight, only on the ground.
Electrical power is not available in flight, only air to one pack.
There is no total electrical failure check-list.
Standby power from the batteries provides electrical power to the standby compass/standby attitude director/standby ASI, for a minimum of 30 minutes.
If any of the 4 generators would not go back on line, then the crew did an excellent job in very difficult circumstances.

Also standby altimeter!

The Staples from Singapore didnt last very long did they? :eek:

Out of curiousity, does anyone know why the RAT was not installed on the 747? There's one on the 757,767 and 777. Did they think that having 4 engines is enough redundancy making RAT an 'unnecessary' feature?

Then again, Airbus didn't think so with the A340

A dc standby power system is provided to supply nominal 24 volt dc power to selected flight critical loads for 30 minutes minimum in the event of complete loss of primary dc power. This system is supplied by two 40 ampere hour nickel-cadmium batteries (main and APU battery), associated
battery chargers, various control relays, the main and APU battery hot buses, and main and APU battery buses.

Try and start the APU if possible and you will loose screens etc.

or the A380...