777 down

[gordner]

There are detection systems for wheel bay fires but not usually supression systems.
And wheel fires occur on take of as well as landing, it can be a result of hot brakes from a long taxi or a bearing failure causing overheat, or a locked brake leading directly to tire ignition. That is why they have the detection systems in place.

[kach22i]

Originally Posted by gordner

There are detection systems for wheel bay fires but not usually supression systems.
And wheel fires occur on take of as well as landing, it can be a result of hot brakes from a long taxi or a bearing failure causing overheat, or a locked brake leading directly to tire ignition. That is why they have the detection systems in place.

I recently watched a X-Prize special featuring the Burt Rutan effort. The main fuel in the rocket booster was a long rubber tube.


http://www.nbcnews.com/id/5226424/ns/technology_and_science-space/t/historic-rocket-powered-rubber-fuel/#.Uyi8mKhdU7k

SpaceShipOne officials have chosen SpaceDev's hybrid rocket propulsion system, shown here during an engine test. The system uses nitrous oxide and a rubber component known as HTPB.

[greglepore]

Would an electrical fire sufficient to take out the transponder/ACAR also take out the comms?

[Seahawk]

Originally Posted by greglepore

Would an electrical fire sufficient to take out the transponder/ACAR also take out the comms?

I was thinking the same thing. The aircraft I flew had essential comm and nav systems on different electrical "buses" to prevent system wide failure in the case of failure (or fire).

I have no insight into the 777.

Here is the fire detection and suppression info: http://www.smartcockpit.com/download.php?path=docs/&file=B777-Fire_Protection.pdf

[kach22i]

Originally Posted by greglepore

Would an electrical fire sufficient to take out the transponder/ACAR also take out the comms?

The article said it is standard procedure in the event of an electrical fire is to shut off all the circuit breakers and turn them back on one at a time.

Had the smoke overwhelmed the crew not all of the panel would have been reactivated including possibly the transponders.

[kach22i]

Originally Posted by Seahawk

Here is the fire detection and suppression info: http://www.smartcockpit.com/download.php?path=docs/&file=B777-Fire_Protection.pdf

From the PDF:................about mid-way in the document and again about 3/4rds way though

Main wheel well has fire detection only.............Nose gear does not have a fire detection system

Neither system has fire suppression.

[cockerpunk]

Originally Posted by greglepore

Would an electrical fire sufficient to take out the transponder/ACAR also take out the comms?

the operators would have turned everything not necessary for control of the aircraft off, if there was some kind of electrical fire, in order to try and stop it. it might not have been turned back on, because the fire had progressed, or the operators were incapacitated.

[greglepore]

Except, as I've understood it to date, the ACAR isn't switchable from the cockpit-although, thinking about it now, that's odd, for just the fire suppression reasons stated. And you wouldn't isolate the a/p as well?

I have to admit, the theory has great appeal, but...

[cockerpunk]

Originally Posted by greglepore

Except, as I've understood it to date, the ACAR isn't switchable from the cockpit-although, thinking about it now, that's odd, for just the fire suppression reasons stated. And you wouldn't isolate the a/p as well?

I have to admit, the theory has great appeal, but...

well that point goes against the notion that a hijacking or someone crazy turned the ACAR off too.

the ACAR could have been damaged in the fire first.

[VaSteve]

Originally Posted by cockerpunk

well that point goes against the notion that a hijacking or someone crazy turned the ACAR off too.

the ACAR could have been damaged in the fire first.

Maybe one thing got damaged and one was shut off. This is an interesting theory that maybe it was set for the nearest airport and just kept going.

[VaSteve]

Originally Posted by intakexhaust

The other day I was thinking about those speculative observations. How many people are up at 1:30 - 2:00 am and catching a plane sighting in the distance?

ONe of the sightings I heard today was the very tip of India. Isn't it like packed there and basically life runs all hours? Maybe someone was up?

[scottbombedout]

If there was a fire and it was that bad, how come the plane managed to fly on for 5 odd hours?

[HardDrive]

Originally Posted by VaSteve

ONe of the sightings I heard today was the very tip of India. Isn't it like packed there and basically life runs all hours? Maybe someone was up?

India is 24/7. Big time.

[VaSteve]

Originally Posted by scottbombedout

If there was a fire and it was that bad, how come the plane managed to fly on for 5 odd hours?

Burning smell **** bad enough to kill you but not take out the engines I guess? Like the Payne Stewart thing...Ghost Plane... Worse would be if the pilots were dead and the people aboard still alive, waiting and couldn't do anything. But it sounds like that wasn't the case anyhow.

[intakexhaust]

Originally Posted by kach22i

From the PDF:................about mid-way in the document and again about 3/4rds way though


Neither system has fire suppression.

So much for redundancy. System like that is probably another half mil. Lives aren't worth it. And the extra weight...... yeah, right......

[intakexhaust]

Introducing for 2014, the 777 Hindenburg.

[Don Plumley]

Jalopnik posts why a fire is unlikely.

Goodfellow's theory is very well-written, and provides a lot of insight from someone with professional experience. It makes sense, and paints the pilots as heroes rather than villains (they may be, we don't know). But here's the kicker — in the comments of his post, he admits that after Sunday's revelation of the hijacking theory from the Malaysia government, the fire theory may be wrong, saying:

[URY914]

As far as this plane landing somewhere and stored for future use, answer me this:

- Don't you need a ground crew of a half dozen guys to get this thing ready to go again?

- Don't you need special refueling equipment of some sort? You can't refill it with gerry cans.

- One rouge pilot couldn't do all this by himself could he?

I'm saying it at the bottom of the ocean.

[ossiblue]

Latest, "confirmed," information.

Thailand reports it's radar picked up the left turn of the plane, supporting the claim of the Malaysian military. That would tend to lessen the likelihood the plane took a northern route (my conclusion.)

Investigators claim the turn was programmed into the computer "at least 12 minutes before" the pilot spoke the last words. That tells me two things. One, the only way investigators could make that claim is if the turn program was reported to the ground via the ACARS report at 1:07 (that's exactly 12 minutes before the last words.). Two, the turn program could have been made at any time from take-off to 1:07, and for any number of reasons, some of which are not necessarily suspect, but not reported until 1:07, and not executed until 1:21.

The last words, "All right, good night," showed no indication of trouble. Two minutes later, the programmed turn was executed. This is the key to the mystery--what happened in those last two minutes?

Pure speculation. From 1:07 to 1:21 is fourteen minutes. That gives the pilots a window in which they could have been dealing with a "situation" they didn't consider serious enough to report, a situation that they were going through their checklist to isolate, a situation that suddenly got out of hand during the final two minutes and either required them to disable the comm. systems or the incident disabled the system. Turn is executed, the rest is unknown.

[tcar]

Originally Posted by onewhippedpuppy

Anything that could ignite the front tire on takeoff would be major enough (locked front brake) that the crew would have known.

There is NOT a brake on the nose wheel.

Nosewheel fires only happen if the tire is significantly deflated/flat... landing or takeoff.