Qantas crash danger: jet loses power

[Dori]

A Qantas 747 with 344 passengers on board could have faced catastrophe after losing power from all four of its generators on its descent into Bangkok on Monday.

A Qantas spokeswoman was unable to say what systems were affected on flight QF2 from London to Bangkok or for how long the aircraft lost power.

The Australian Transport Safety Bureau said it had been told the power from the main generators was lost 15 minutes away from Bangkok.

The pilot was then forced to switch to battery back-ups for the landing.

"This incident involved loss of electrical power on a Boeing 747 on descent into Bangkok," Qantas chief pilot, Captain Chris Manning, said in a statement.

"The back-up system was activated and the aircraft landed safely.

"Qantas reported the incident to Boeing, the Australian Transport Safety Bureau and the Civil Aviation Safety Authority and is also conducting its own thorough investigation. The aircraft is currently being repaired and assessed."

A spokeswoman added: "Because it is under investigation, we are unable to provide any further information at this stage."

If the power failure had occurred further away from an airport there could have been a serious accident, Australian Transport Safety Bureau deputy director of aviation Julian Walsh said.

"Obviously there's a limit to the battery power that's available," Mr Walsh said.

"Obviously, if they were a long way from an airport then clearly there would have been potential for some sort of accident.

"All we've been advised is that there was a failure of the four electrical generators on the aircraft 15 minutes out of Bangkok - it's quite unusual."

Mr Walsh said he was liaising with his Thai counterparts to see if they would investigate the incident. If they did investigate the ATSB would send a representative to assist, he said.

[landofsmiles]

From an Aussie paper>>>

QANTAS faced a potential disaster on Monday when a jumbo jet en route from London lost 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 $100 million 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," he said.

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 Australian

[landofsmiles]

Not the first time they've had generator failures either.

MAY 2, 2000: Flight QF128 was forced to return twice to Hong Kong airport after a warning light indicated a generator had failed.

The same aircraft underwent $100 million in repairs after it overshot the runway at Bangkok.

[The Loop]

Thank god they were in reach of an airport and were able to land safely.
These planes have been around a long time,wonder if one has ever gone down due to this type of problem.
Bit unusual,4 simultaneous failures,though.

[22poolip]

From crikey.com.au

Qantas unplugged
Ben Sandilands writes:



If it wasn’t so serious it might have been funny.


Water leaking from a galley appliance put the 360 souls aboard QF2 in mortal peril on Monday afternoon as the Boeing 747-400 was descending toward Bangkok from London.


It seeped into the only spot inside the airframe where the power feed from four engine driven generators comes together to drive the main electrical system, and shorted it.


The cause of the seepage? A drain and drip barrier which informants claim wasn’t replaced after the jet underwent maintenance in Sydney.


A safe landing was made after 15 minutes running on a one hour battery and invertor back-up system. The professionalism of the pilots and cabin crew was of the highest standard. They dealt with a bungle that could have ended in disaster had the supply been cut off at cruising altitude, especially if at night and far from an adequate emergency runway, with most instruments no longer working and little if no engine power and a host of electrically assisted processes.


What is in the gun now is the calibre of Qantas maintenance in Australia and the capacity of management to ensure all jets are correctly maintained and airworthy.


Late last year Qantas workers at Melbourne topped up the emergency oxygen system in one of its 747s with nitrogen supposed to be used on the tyres.


It is an error that would have swiftly incapacitated both pilots in an emergency in which they put on the masks because of a cabin depressurisation or fumes or smoke in the cockpit.


The independent safety investigator the ATSB decided not to inquire into that deadly screw up but has taken up this latest incident.


And at CASA which favours the self-administration of safety rules, the question that the new government might reasonably ask is when and how often have its inspectors actually checked that all of the work that is signed off as being done on a Qantas jet is actually being done. A large fibre glass drainage shield is pretty hard to overlook.


Is there another explanation for the QF2 incident? Qantas clearly doesn’t think so. Within hours of the jet being inspected in Bangkok every one of its 747s was specifically checked before departure for missing items of plumbing.

[Soupdragon]

Who would have the job of an aircraft designer having to think about every eventuality that could cause incidents in flight. A dripping tap and a missing/damaged splashguard has the potential to down a 747, thats just scary. Just shows how important the job of the flight crew in reporting everything no matter how trivial and the maintenance engineers in doing the job to the letter is. Does this happen in every case, obviously not.

Originally Posted by 22poolip

Late last year Qantas workers at Melbourne topped up the emergency oxygen system in one of its 747s with nitrogen supposed to be used on the tyres.

It is an error that would have swiftly incapacitated both pilots in an emergency in which they put on the masks because of a cabin depressurisation or fumes or smoke in the cockpit.


The independent safety investigator the ATSB decided not to inquire into that deadly screw up but has taken up this latest incident.

That doesn't sound right, surely the ground crew would have had to put a very high percentage of nitrogen in the O2 system before anyone would experience hypoxia breathing it ?? Maybe thats why the ATSB didn't do a full inquiry into this incident, maybe it is even common practice if sufficient O2 isn't available ???

[suakopannu]

Scary stuff for someone who flies alot

[pablo]

As for the B747 (Qantas) incident, not that big of a deal IMO.

Sounds like the media making a mountain from a mole hill.

In the first place, a "bus fault" that would isolate and "trip" all 4 electrical generators off line, IS a serious condition. There are however, procedures with which to troubleshoot, and restore generating capacities. (lengthy and time consuming)

Also, the battery power (for ESSENTIAL power), is certified for a minimum of 30 minutes usage. However, on long range (over water) aircraft, such as the B747...there is a redundant electrical generating system, used to keep the batteries "topped off", in case of such an event. Thus, the use of "essential" flight instruments and equipment, can go on indefinitely.

(This redundant generating system can be either "ADG", air driven generator...or perhaps "HDMG", hydraulic driven motor generator. And, in most cases, these are activated automatically. The sole purpose being, to assure continued battery power.)


These aircraft operate (at times) in over water routing's that place them as much as 2 to 3 hours from the nearest alternate airport. Therefore, designs are in place to insure continued operation of "essential equipment", in the case of (total) electrical generator failure.

When operating on "essential" power only, the pilot is well able to fly, navigate and communicate. However, there will likely be no cabin lighting, movies, dinner service, etc. 55555

If I were the Captain on this flight, and was 15 minutes from landing at BKK, when the failure occurred...I'd probably elect to continue on battery power only (essential), and complete the landing. No sense in trying to reinstate the system (not necessary for continuation), when landing is so imminent....as opposed to being over water, and hours from the nearest landing site.

The press does a good job of sensationalizing most airline incidents. They must love to scare the hell out of the public.

The pilots did a great job, and don't think of them as "Sky God's"...just everyday hero's. 55555

[aussie dollar]

Originally Posted by landofsmiles

Not the first time they've had generator failures either.

MAY 2, 2000: Flight QF128 was forced to return twice to Hong Kong airport after a warning light indicated a generator had failed.

The same aircraft underwent $100 million in repairs after it overshot the runway at Bangkok.

where do u find these incidents is there a data base,was on singapore flight which aborted takeoff would be interested to find out why ?

[Soupdragon]

Originally Posted by pablo

(This redundant generating system can be either "ADG", air driven generator...or perhaps "HDMG", hydraulic driven motor generator. And, in most cases, these are activated automatically. The sole purpose being, to assure continued battery power.)

That's that little windmill affair that pops out of the bottom of the aircraft and drives a small generator, saw that on Air Crash Investigation when a plane ran out of fuel and the pilot performed the longest glide in a commercial jet to land safely.

Do you have any comment on nitrogen being used in the O2 emergency system Pablo ???

[pablo]

Originally Posted by Soupdragon

That's that little windmill affair that pops out of the bottom of the aircraft and drives a small generator, saw that on Air Crash Investigation when a plane ran out of fuel and the pilot performed the longest glide in a commercial jet to land safely.

Do you have any comment on nitrogen being used in the O2 emergency system Pablo ???

I think you're referring to the Air Canada B767 that ran out of fuel. (faulty gauges) You're correct, the ADG will deploy out of the underside...and they somewhat resemble a small outboard marine motor. (propeller driven) On some aircraft (DC10 & MD11), they may be used to provide hydraulic power for flight controls, as well as electric.

Nitrogen is commonly used for servicing tires, hydraulic accumulators and such. It is void of water, and therefore won't freeze. (good idea)

I don't think that Nitrogen works too well on human lung function, however. 5555 (I'm not a doctor, and I don't play one on a TV show)

I once caught mechanics at Heathrow, ready to pump up a flat tire with breathing oxygen instead of nitrogen. But, I've never seen the other way around, for an O2 system. 55555

[landofsmiles]

Originally Posted by Soupdragon

That's that little windmill affair that pops out of the bottom of the aircraft and drives a small generator, saw that on Air Crash Investigation when a plane ran out of fuel and the pilot performed the longest glide in a commercial jet to land safely.

Yeah they're good to watch and they're all on youTube. That would be the AirTransat that glided into the Azores?

YouTube - Air Crash Investigation: Flying on Empty Part 1

The BA 747 that lost all 4 engines going through volcanic ash is good too>>>

YouTube - Air Crash Investigation: All Engines Failed Part 1

[Soupdragon]

Originally Posted by pablo

I think you're referring to the Air Canada B767 that ran out of fuel. (faulty gauges) You're correct, the ADG will deploy out of the underside...and they somewhat resemble a small outboard marine motor. (propeller driven) On some aircraft (DC10 & MD11), they may be used to provide hydraulic power for flight controls, as well as electric.

Nitrogen is commonly used for servicing tires, hydraulic accumulators and such. It is void of water, and therefore won't freeze. (good idea)

I don't think that Nitrogen works too well on human lung function, however. 5555 (I'm not a doctor, and I don't play one on a TV show)

I once caught mechanics at Heathrow, ready to pump up a flat tire with breathing oxygen instead of nitrogen. But, I've never seen the other way around, for an O2 system. 55555

The plane than ran out of fuel was an airbus, mechanics had fitted a new engine but used an incorrect bracket in the wing which allowed the fuel pipe to rub on another component and chaff through. The pilot got an fuel imbalance warning as fuel leaked from the wing so operated the fuel crossflow pump to correct this and basically left it open until all the fuel had leaked out. Mind boggling really really would have thought they would realise they had a leak and stopped the fuel transfer. I believe they thought they had a computer problem and disregarded all the warnings.

Please don't recount too much of what you have seen behind the scenes with regards to mistakes being made. I love to fly and would like to keep it that way. 5555555

[pablo]

Originally Posted by Soupdragon

The plane than ran out of fuel was an airbus, mechanics had fitted a new engine but used an incorrect bracket in the wing which allowed the fuel pipe to rub on another component and chaff through. The pilot got an fuel imbalance warning as fuel leaked from the wing so operated the fuel crossflow pump to correct this and basically left it open until all the fuel had leaked out. Mind boggling really really would have thought they would realise they had a leak and stopped the fuel transfer. I believe they thought they had a computer problem and disregarded all the warnings.

Please don't recount too much of what you have seen behind the scenes with regards to mistakes being made. I love to fly and would like to keep it that way. 5555555

Yes, I recall that incident as well. I think the Airbus crew landed in the Azore's, under emergency.

The Air Canada B767 occurred a long time ago, and if memory serves...they "glided" into an abandoned military field somewhere near Montreal.

"You'll probably be OK" 5555

[The Loop]

Originally Posted by pablo

no cabin lighting,movies, dinner service, etc.

Oh my god,thats way too scary.
Hang on thats how i always fly,Jetstar.

Originally Posted by Soupdragon

Do you have any comment on nitrogen being used in the O2 emergency system Pablo ???

The air we breath is made up of about 78% Nitrogen,the emergency systems are designed to regulate enough nearly pure O2 to keep you alive for so long.So obviously there would be a problem if there was a mix.

[faultytowers]

Originally Posted by 22poolip

Late last year Qantas workers at Melbourne topped up the emergency oxygen system in one of its 747s with nitrogen supposed to be used on the tyres.


It is an error that would have swiftly incapacitated both pilots in an emergency in which they put on the masks because of a cabin depressurisation or fumes or smoke in the cockpit.

Originally Posted by The Loop

The air we breath is made up of about 78% Nitrogen,the emergency systems are designed to regulate enough nearly pure O2 to keep you alive for so long.So obviously there would be a problem if there was a mix.

Can't comment on the situation with planes but with hospitals it is now impossible to top up oxygen tanks with any other gas . All pipelines and fittings are different sizes/configurations for each specific gas , and all emergency oxygen systems must be fitted with analyzers to monitor the percentage of oxygen.

[Spector]

Originally Posted by pablo

Yes, I recall that incident as well. I think the Airbus crew landed in the Azore's, under emergency.

The Air Canada B767 occurred a long time ago, and if memory serves...they "glided" into an abandoned military field somewhere near Montreal.

"You'll probably be OK" 5555

You guys are both right. Both out of fuel emergency landings were Canadian carriers. The Air Canada Flight in the 70’s was an error in fueling in Toronto during the metric conversion from gallons to litres. This resulted in not enough fuel being added.

The second one was an Air Transat charter flight out of Toronto that ran out of fuel due to a major engine fuel leak. (wrong parts installed on engine change) It landed in the Azores. The pilot was held up as a hero and then chastised when it was discovered he served time in South America for drug running. Maybe that’s how he learned to fly so well….5555…

[Soupdragon]

Originally Posted by faultytowers

Can't comment on the situation with planes but with hospitals it is now impossible to top up oxygen tanks with any other gas . All pipelines and fittings are different sizes/configurations for each specific gas , and all emergency oxygen systems must be fitted with analyzers to monitor the percentage of oxygen.

I would hope that the airline industry apply the same logic. If they can use the same equipment to fill the emergency O2 system as the tyres there is a real risk of contamination, not of the breathing gas, that would be neglible, but if hydrocarbons were introduced into an O2 system under pressure, well you know what happens next, BOOOOOM.

[geespot]

Scary I flew QF2 LHR-BKK 6 weeks ago probably on the same place

The plane was a sh*t hole

G

[MrDK]

Originally Posted by pablo

I don't think that Nitrogen works too well on human lung function, however. 5555 (I'm not a doctor, and I don't play one on a TV show)

Fresh (breathing) air comprise 78% nitrogen (N2) and 20.9% oxygen (O2) and 1.1% other trace gases (water vapors, CO2 and Argon). At sea level or equivalent pressure (1 atm) loss of coordination for a healthy person sets in below 18% O2 and at 10,000 feet (eq) at 19.5%. For most, 12% O2 (1 atm) is survivable. At 0% O2 or 100% N2 a person would faint in 1 single breath and likely not take more than a second and obviously die within a few seconds.