FlyerTalk Forums

FlyerTalk Forums (https://www.flyertalk.com/forum/index.php)
-   Other Middle Eastern and African Airlines (https://www.flyertalk.com/forum/other-middle-eastern-african-airlines-471/)
-   -   ET / Ethiopian 787 "Dreamliner" catches fire at LHR [12 Jul 2013] (https://www.flyertalk.com/forum/other-middle-eastern-african-airlines/1484336-et-ethiopian-787-dreamliner-catches-fire-lhr-12-jul-2013-a.html)

Firewind Jul 30, 13 10:41 am


Originally Posted by DaviddesJ (Post 21183254)
Why is pressurization important for a flight with no passengers, and possibly at a low altitude?

Hey, I'm the one asking the questions and you're the expert. :D But seriously, I don't know. I would think that the crew, and maybe some systems, would need the same conditions as passengers, or to need to operate to a design objective. If the fuselage is not sealed, would they fly with masks and more? And would a unitary (meaning the parts relying on the whole) fuselage be subject to (partially) imploding? I've read that the composite is just as strong as aluminum, but I probably can't conceive of what all the issues would be with a crippled plane.

DaviddesJ Jul 30, 13 3:12 pm

There's nothing on the plane that needs pressurization to operate. The plane needs to be able to survive depressurization at altitude and land safely, after all. The crew could either just fly at a low enough altitude to not require pressurization, or they could use masks. That doesn't seem like a big deal to me, for a single shuttle flight.

I wonder what the range of the 787 is if it has to stay at a relatively low altitude for the whole flight. Should still be plenty to cross the Atlantic.

ffsim Jul 30, 13 3:38 pm


Originally Posted by DaviddesJ (Post 21185247)
I wonder what the range of the 787 is if it has to stay at a relatively low altitude for the whole flight. Should still be plenty to cross the Atlantic.

Considering AC uses a 319 on its YYT-LHR route, I think that's a safe assumption ;)

DaviddesJ Jul 30, 13 10:27 pm


Originally Posted by ffsim (Post 21185434)
Considering AC uses a 319 on its YYT-LHR route, I think that's a safe assumption ;)

How does this relate to the question? I don't know what the fuel economy of a 787 is at 8000 or 10000 ft, compared to normal cruising altitude. Probably a lot worse. Do you know? The 319 certainly flies a lot higher than 10000 ft.

Scrooge McDuck Jul 31, 13 2:29 am


Originally Posted by DaviddesJ (Post 21185247)
There's nothing on the plane that needs pressurization to operate. The plane needs to be able to survive depressurization at altitude and land safely, after all. The crew could either just fly at a low enough altitude to not require pressurization, or they could use masks. That doesn't seem like a big deal to me, for a single shuttle flight.

True, but that is not the point. The question is if the damage effects the structural integrity of the frame or if the flight might/will cause more (hidden) damage to the structure or hull of the plane. If that is/might be the case, then flying the plane to a repair station ends up rather dangerous. Just have a look at China Airlines flight 611 or Japan Airlines flight 123. Both crashes were caused by bad repair jobs.

I personally would feel much safer if the repair job is done at LHR.

ffsim Jul 31, 13 6:20 am


Originally Posted by DaviddesJ (Post 21187444)
How does this relate to the question? I don't know what the fuel economy of a 787 is at 8000 or 10000 ft, compared to normal cruising altitude. Probably a lot worse. Do you know? The 319 certainly flies a lot higher than 10000 ft.

How does it relate? You were wondering about the range of the 787 should it need to fly across the Atlantic at a low altitude. As you admit, you don't know how much less efficient the 787 is at lower altitude as opposed to cruising altitude. I'll admit that I don't know, either.

However, an A319 carries about 24 000 litres of fuel whereas a 787 carries about 127 000 litres. So, unless you're suggesting the 787 is 80% less efficient at low altitude than the 20 year old A319 is at cruising altitude, it should easily be able to cross the Atlantic.

As I suggested in my post, I think it's a safe assumption.

Firewind Oct 22, 13 6:14 am

Pushing the Limits?
 
"...pushing the limits"?

http://seattletimes.com/html/busines...repairxml.html

Firewind Nov 24, 13 12:44 am

Now, with all the news about the Dreamlifter that landed at the wrong airport, we see that Boeing actually had the wherewithal to fly in a fuselage section, instead of just a patch.

Firewind Jan 9, 14 2:46 am

All Done
 
All done. And back on the line since 23 December...

http://seattletimes.com/html/busines...87firexml.html


Flightaware, which tracks airplane flights, shows the jet on a Dec. 23 scheduled flight from Frankfurt, Germany, to Ethiopianís base in Addis Ababa.

ETStar Jan 22, 14 11:49 am


Originally Posted by Firewind (Post 22116395)
All done. And back on the line since 23 December...

http://seattletimes.com/html/busines...87firexml.html

Flew her ex YYZ on her first trans atlantic after the fire. She was awesome!

JDiver Aug 19, 15 7:26 am

It seems the investigation is over; the fire was caused by a wiring fault. No indication if the problem can be assigned to Boeing, Honeywell or the equipment installer. Clear case of poor workmanship and quality control, it would seem (from the perspective of someone who did similar work wiring, installing and maintaining precision electronic equipment) and the battery thermal problems.

The boffins say if the short circuit had occurred in the air, the very cold ambient temperatures would have prevented similar damage in flight - perhaps the same people who though a short would only drain the battery?


BBC: 19 Aug 2015 - A fire on a parked Boeing 787 Dreamliner jet at Heathrow Airport two years ago was probably caused by a short circuit, air accident investigators have said.

The fire was likely to have been started by two bare wires touching in a piece of location equipment, the UK Air Accidents Investigations Branch said.

...

The piece of equipment that caught fire - the Emergency Locator Transmitter (ELT) - was located near the back of the plane, and was made by Honeywell, investigators said.

...

The device in the 787 had positive and negative cables that were too long to fit into the box housing the device, and so ended up touching one another.

Testing had predicted that the worst reaction from a short circuit would be the batteries running down.

Unfortunately, what actually happened was what investigators called "a thermal runaway" - a fire that spread from one battery cell to the next.

http://www.bbc.co.uk/news/business-33985615

Firewind Aug 19, 15 1:32 pm

Thank you, JDiver.

Firewind Aug 20, 15 11:39 am

However...

http://www.seattletimes.com/business...ut-mid-flight/

Sabasi Aug 21, 15 1:08 am

The safety of all 787 aircraft has been questioned in serious reporting about their manufacture and assembly, including interviews with the employees and contractors involved in both. This does not promote confidence in ET's decision to purchase the early manufactured aircraft that had been stored for years.


All times are GMT -6. The time now is 8:31 pm.


This site is owned, operated, and maintained by MH Sub I, LLC dba Internet Brands. Copyright © 2021 MH Sub I, LLC dba Internet Brands. All rights reserved. Designated trademarks are the property of their respective owners.