MH370: Malaysian Airlines Flight to Beijing carrying 239 people is lost over sea.

[Grayfox]

Has anyone look for the plane in North Korea?

 

[Mike Rotch]

The Chinese are claiming to have found more debris via satellite images and will be having a press conference shortly:

http://www.smh.com.au/world/missing...y-chinese-satellite-image-20140322-35ap6.html

 

[Bopop4]

My main concern with jumping from the 777 would be clearing the horizontal stabilizer on the way out

That wouldn't be an issue, you'd fall well clear of it.

The tail on something like a Cessna is a lot closer than that of the Boeing, and you could slow down to under 200mph if you threw full flaps on the airliner.

 

[TenEightyOne]

They'd end up with 200 credit cards and no PIN numbers. The cursing as he descended with parachute would have echoed around the world

Haha, you might find this incredible but US cards don't have a PIN! They're very insecure, some even still use a "signature" from the holder

By "going through wallets" I was referring to generally doing as one wishes according to whatever purpose one has on one's mission... but "going through wallets" sounds a little more innocent (after killing 270 people...)

@Bopop4 No, that doesn't really compute... you leave a Cessna at about 100kias max, 3m from the rear control surface, and you drop faster than the airflow carries you.

On a 777 the distance from the rear of the wing root to the front of the stab is about 30m but you're going to leave at nearer 220-250-kias. Leaving through a door is going to get you minced. Running below that speed will begin to require 5 or 10' of flap, auto throttle (unless your accomplice is happy to stay on the flight deck) and a programmed descent unless you want the plane to maintain altitude when you jump... in which case you'd be flying slightly nose-up which increases the chances of becoming a disappointed smear on the rear control surfaces.

Go out through the cargo hatch, it's a no-brainer, although you would still set the autopilot for course/alt maintenance

 

[Grayfox]

Go out through the cargo hatch, it's a no-brainer, although you would still set the autopilot for course/alt maintenance

Cargo hatch is locked from outside and can not be opened from with inside.
A few Airlines have crashed due to the cargo door opening by it self when at altitude.

 

[TenEightyOne]

Cargo hatch is locked from outside and can not be opened from with inside.
A few Airlines have crashed due to the cargo door opening by it self when at altitude.

You're absolutely right, however in the 777 the door is a plug design that's so secure the 777 checklist presumes that if the cabin is pressurised-at-altitude then CARGOHATCH warnings absolutely can't be a result of it opening*.

However, if you're below pressurised altitude and you weren't planning to resell the plane.... you could easily persuade the door to part company.

*EDIT: Checklist says that if cabin pressurisation is normal then door is secure, if pressurisation changes (no mention of oxygen deployment but this is a cascaded checklist) then PIC should consider further reducing inner/outer pressure difference to decrease risk of separation and reduce altitude to 8,000ft.

 

[Grayfox]

Main issue is why did the pilots add a new course into the auto pilot?

If they died due to smoke or decompression the plane will continue to the airport, then go into a holding pattern then crash a few hours later, unless they tried a Airport 1975 styled rescue.

 

[Bopop4]

On a 777 the distance from the rear of the wing root to the front of the stab is about 30m but you're going to leave at nearer 220-250-kias. Leaving through a door is going to get you minced.

???

When you jump out of an airplane you drop, 100ft is more than enough room to clear the tail.
You can run it to 150 knots, not much faster than what a 206 can do.

 

[Grayfox]

???

When you jump out of an airplane you drop, 100ft is more than enough room to clear the tail.
You can run it to 150 knots, not much faster than what a 206 can do.

But at 700km/h you do not drop fast enough to clear the wings.

 

[TenEightyOne]

My guess is, if this was an emergency scenario, they were dialling a course on-the-fly.

Reports from ground monitoring say that the corrections were made by "typing on the center console", that implies that the course was set on the Flight Management Computer, this is at the upper left edge of the pilot's center console (left seat) and in the mirrored position for the first officer. That is (a) a peculiar piece of data to have from a plane that supposedly didn't have any data services and (b) completely contradictory to what I'm about to describe

If the aircraft's AP is still operable then it's quite normal to fly the plane by just adjusting the knobs on the autopilot interface which is along the top of the main console just below the windscreen. You can watch any number of 777 approach videos to see how routine this is.

In an emergency you'd aviate, navigate, communicate. You may well aviate by holding alt with the AP, holding course, then dialling your course changes in. That's what I'd expect to have happened here (providing AP is working, seems it may have been due to some weird sequence of events). The fact that the course was dialled at the FMC contradicts this though, as I said.

???

When you jump out of an airplane you drop, 100ft is more than enough room to clear the tail.
You can run it to 150 knots, not much faster than what a 206 can do.

That's a 206 at max, not safe exit speed, and if you think you'll easily fly a laden 777 with the doors open at 150kias then you're Chuck Yeager. Think where the tailplane is at that speed...

 

[Bopop4]

But at 700km/h you do not drop fast enough to clear the wings.

Why not?

Look at drop tanks on fighters, they're going much faster than that, with a much shorter length, and they have no problem getting enough safety between the wing and the tanks.

That's a 206 at max, not safe exit speed, and if you think you'll easily fly a laden 777 with the doors open at 150kias then you're Chuck Yeager.

Again, why not?

You can fly aircraft with many objects attached to it, and still have it fly perfectly fine.
Creating some extra drag on the fuselage isn't going to make it spin out of control on a huge aircraft.

 

[TenEightyOne]

Look at drop tanks on fighters, they're going much faster than that, with a much shorter length, and they have no problem getting enough safety between the wing and the tanks.

The ones that are mounted under the wings? I could never figure out how they miss the wings... and they don't just "drop", do they? Some are forced (to stop them jamming) and most have aero on a tailpiece that drops to "pull" them down.

EDIT: And doesn't one pull up to help release, iirc?

You can fly aircraft with many objects attached to it, and still have it fly perfectly fine. Creating some extra drag on the fuselage isn't going to make it spin out of control on a huge aircraft.

I don't disagree overall, but I entirely disagree with what you're actually theorising; you could open the door on a 777 with 270 passengers, luggage and cargo aboard and (at the Andaman Islands) 5 hours-worth of fuel and then fly it at 150kias at 8000ft in order to jump from the doorline and clear the tailplane.

I hesitate to say this but I have to wonder if you know what you're talking about or the difference in airflow 'intensity' over 90kias, the Cessna is only just above the top of that envelope at jump speed, the 777 is at nearly double that at the base of its control envelope. I also wonder if you're aware if the differences in air pressure between sea level and 8000ft above.

The door is unusually relevant at that speed because the aircraft is at the limit of control.

 

[Bopop4]

The ones that are mounted under the wings? I could never figure out how they miss the wings... and they don't just "drop", do they? Some are forced (to stop them jamming) and most have aero on a tailpiece that drops to "pull" them down.

Gravity.

Most tanks don't have any aero devices on them, only the larger ones do and that's just to help keep the aircraft stable.

I don't disagree overall, but I entirely disagree with what you're actually theorising; you could open the door on a 777 with 270 passengers, luggage and cargo aboard and (at the Andaman Islands) 5 hours-worth of fuel and then fly it at 150kias in order to jump from the doorline and clear the tailplane.

Those aircraft are very stable, and an autopilot can keep it at that speed too.

I hesitate to say this but I have to wonder if you know what you're talking about or the difference in airflow 'intensity' over 90kias, the Cessna is only just above the top of that envelope at jump speed, the 777 is at nearly double that at the base of its control envelope. I also wonder if you're aware if the differences in air pressure between sea level and 8000ft above.

The door is unusually relevant at that speed because the aircraft is at the limit of control.

I could say the same thing back.

You fall at the same speed, because you don't have wings.

If the aircraft is going double or even triple the speed of the 206, but it's more than double or triple the distance to the tail, then you're not going to hit.

On a light aircraft, even if you jump and try to hit the tail, you can't.

If the 777 can take off at that speed, and it still has a safe zone in that, then the door would be fine.[/quote]

 

[TenEightyOne]

Most tanks don't have any aero devices on them, only the larger ones do and that's just to help keep the aircraft stable.

Fair enough, however they're still below the wings. Those mounted higher than the tailplane still jettison to clear.

Those aircraft are very stable, and an autopilot can keep it at that speed too.

I've flown a 777 at 190kias at 6000ft in a simulator and even with light winds-aloft it was not stable by any means. Do you know the difference in air pressure at those altitudes? DCS simulates it very well so you must, think of the change in SU25 turn circle at 400kias for varying altitudes. Why is the stall angle so much lower at altitude?

You fall at the same speed, because you don't have wings.

Correct, but consider the rapidity of your decellaration against the continued speed of the aircraft. The ratio is massively different from the Cessna example to the 777 example.

On a light aircraft, even if you jump and try to hit the tail, you can't.

I know, although I'd never try it personally. I'm not disputing that this is possible, in fact I think it's a good thing as it keeps nutters occupied all day Saturday.

If the 777 can take off at that speed, and it still has a safe zone in that, then the door would be fine.

Not much of a safe zone clearing a loaded 777 at that speed, and that is at sea level.

 

[Bopop4]

I'll be starting by explaining the difference between what an aircraft can do at sea level and what it can do at 8,000 feet, the lift differential is immense.

That's assuming takeoff speeds, which I just realized doesn't have to be that low because there is so much space the the tail.

 

[BobK]

@Bobop4, the thing is, as you slow a plane down you have to raise the nose. And when you raise the nose, the tail moves down. Flying a 777 at 150 kts is getting pretty close to the stall speed so you'd have to raise the nose (and lower the tail) quite a bit; the horizontal stabilizer would be well below the level of the exits.

 

[TenEightyOne]

Edited my reply, sorry for the delay

In other news, as @Mike Rotch points out, China looking at second possible debris field. At the moment debris news isn't so exciting, there's so much stuff floating around the oceans that they could keep this up for ages. Sadly the ELT may only have another 10-20 days? We're into week three so possibly.

 

[Jordan]

I'm skeptical about the "fire" theories, but this is something of an interesting development, as Malaysian Airlines has confirmed the 777 was carrying lithium-ion batteries as cargo:

http://feedly.com/k/1ioV5l0

 

[Vic Reign93]

http://jalopnik.com/mh370-families-reportedly-kicked-out-of-hotel-for-ferra-1549390817

Spotted this whilst checking Jalopnik and thought would be slightly relevant to the topic.

 

[ExigeEvan]

While I fully support the investigation of every object, I do think the media around 'an item' is all a bit much, there are loads of things floating around the deep oceans, and until we see a positive collection of debris I would not build anyone's hopes up.

 

[TenEightyOne]

While I fully support the investigation of every object, I do think the media around 'an item' is all a bit much, there are loads of things floating around the deep oceans, and until we see a positive collection of debris I would not build anyone's hopes up.

Exactly, there's a lot of debris out there.

I'm skeptical about the "fire" theories, but this is something of an interesting development, as Malaysian Airlines has confirmed the 777 was carrying lithium-ion batteries as cargo:

http://feedly.com/k/1ioV5l0

I quite agree, this is another possibly-connected fact to fit into the unconnectable puzzle. I still don't go with the fire theory but it can't be excluded, whatever happened is a version of one of the existing theories with something random and possibly incredible thrown in.

@Famine, I still make the groundspeed for your route nearer 600mph, kias convert at 6:7 I think, cruise is M0.84 or around 300kias at cruise altitude, that's about 520kigs and about 600mph. That's some range...!

That's assuming takeoff speeds, which I just realized doesn't have to be that low because there is so much space the the tail.

No, although you could "bottom off" the wing from that escape door, possibly. The other doors are too close to the tail. You need to keep the plane level which, with your load, requires over 220kias. Have you flown a 777?

EDIT: Just spotted this on a re-read of the article linked by Jordan;

Malaysian investigators say they believe that the plane was commandeered, and one fact in particular they have released does not fit the fire theory. They say that the plane changed its course prior to a final radio communication in which the co-pilot said "good night" to air-traffic control — a routine call that made it seem like everything was fine.

Read more: http://www.businessinsider.com/malaysia-plane-lithium-ion-batteries-2014-3#ixzz2wjMHJ3Qs

If that's correct then the pilots were involved or already under coercion at that time. I simply cannot imagine that a single passenger wouldn't have got a message out if they were aware that coercion was in progress.

 

[Crash]

Impossible since the doors are pushed against the hull by the internal air pressure of the plane, so you won't be able to open them.

Unless, of course, you disable the cabin pressurization. Why not? You're at 8000 feet after all.

Most large metallic fuselage commercial planes in service today are pressurized to 8000 feet. If the plane is flying at that level, the pressure inside and outside the cabin would be the same, not that you would even need the pressurization system to be on anyways at that altitude.

 

[TenEightyOne]

@Crash, absolutely right... I included the checklist quote further up.

The crew can presume on a CARGOHATCH warning that if cabin pressurisation remains stable then the door is in place and intact, one of the remedies to balance a loose door is to deploy oxygen, depressurise, and in any event make for 8000ft.

EDIT: And more on why the fire theory might not be such a good one, from 777 pilots...

 

[eran0004]

I simply cannot imagine that a single passenger wouldn't have got a message out if they were aware that coercion was in progress.

Why tell the passengers? Most of them were probably sleeping, and even if they weren't it was in the middle of the night so they wouldn't have been able to see if the plane was at a lower altitude than usual.

Or they could simply have invented a fake story about having to return to the airport for whatever reason.

 

[ExigeEvan]

Why tell the passengers? Most of them were probably sleeping, and even if they weren't it was in the middle of the night so they wouldn't have been able to see if the plane was at a lower altitude than usual.

Or they could simply have invented a fake story about having to return to the airport for whatever reason.

Minor point, would the planes in flight entertainment system have included a "current location" map? Whilst I'm sure this could be switched off, potentially shutting down the entire IFE might provoke a lot of questions from the passengers.

 

[TenEightyOne]

Why tell the passengers? Most of them were probably sleeping, and even if they weren't it was in the middle of the night so they wouldn't have been able to see if the plane was at a lower altitude than usual.

Or they could simply have invented a fake story about having to return to the airport for whatever reason.

I meant more that if people in the passenger compartment had taken hostages and forced the crew to admit them to the flight deck then passengers would naturally have been alarmed. If the perps did it with a note, showed a steward an apparent bomb or weapon, maybe they did it more surreptitiously than Steven Seagull might have been able to

@ExigeEvan no, they just switch over to Disaster at 30,000 ft and everybody's happy I'm sure they have an option to do that now, it was a point of concern for some passengers on the QANTAS jet that they were able to flick between "Roadhouse" and "Your Plane's Falling Apart". Either the option to kill the live data feeds to the passenger cabin didn't exist at that time or the crew didn't consider it.

If the map was switched off (maybe replaced with a blank page showing the airline logo) most people wouldn't really consider it to be a matter of concern, in my opinion.

EDIT: @Bopop4 , I hate this bit... I stand corrected. The overwing door on the 200 is rear of the wing, I must have been thinking of the 300 door which is over the wing (and so doesn't have a chute).

That's a door you could go out of I think, but it's very risk to jump onto the top of jetflow, I still don't think you'll easily clear the tailplane, the aero around there is immensely powerful. Interestingly though there's actually a service door on the lower rear starboard that takes crew steps if required. If you could get to the cargo hatch then there's a perfect inward-opening aperture (the main cargo hatches release outwards).

You're still dead wrong about the flyability:altitude stuff

 

[Bopop4]

You're still dead wrong about the flyability:altitude stuff

Not really, no.

The aircraft won't have a terribly large AoA at 250kts.

You'd still have a ton of space to the tail, the only risk is the actual windblast and riveting.

Hitting the wind at 250kts would require a helmet or it would hurt pretty bad, and the riveting could also hurt you depending on how you rolled.

 

[Grayfox]

I'm skeptical about the "fire" theories, but this is something of an interesting development, as Malaysian Airlines has confirmed the 777 was carrying lithium-ion batteries as cargo:

http://feedly.com/k/1ioV5l0

But they "were" packed according to the FAIs instuctions on Li-ion Battery transport.
Batties dont explode like bombs but burst and they talk about thermal runaway but can a battery go into thermal runaway when their is no circuit.

 

[TenEightyOne]

The aircraft won't have a terribly large AoA at 250kts.

I'm sure I told you that?

You need to keep the plane level which, with your load, requires over 220kias. Have you flown a 777?

Ah yes.

You can run it to 150 knots, not much faster than what a 206 can do.

Oh.

You're also, I'm going to say this again, at 8000ft above sea level. You are not at sea level, not by any means.

I just tried this evening, with the passenger, fuel and (presumed) cargo load you stall at about 155kias in still air. With very mild air movement and gusts the safe limit is near 165kias (by safe I mean doesn't suddenly stall and pitch the plane out of the recoverable angle). You don't want to know where the nose is at level flight at that speed. You'd struggle to climb from the rear seats to the cockpit, that's for sure. To decrease this angle you can deploy a lot of flap but then you're pretty much guaranteeing being blown upwards into the tailplane when you hit the doors. That's massive aero.

@Grayfox and @Jordan, I found an article at the quite incredible Battery University (I know!) about what causes fires/melts in Li-ion batteries. I guess a manufacturing defect in a separator could cause an issue in a packed quantity? That said, I'm sure the manufacturers/transporters are well aware of the risks, and Boeing too

Uneven separators may also trigger cell failure. Poor conductivity due to dry area increases the resistance, which can generate local heat spots that weaken the integrity of the separator. Heat is always an enemy of the battery. When fully charged, elevated temperature causes a harmful reaction between the positive and negative electrodes and the electrolyte. As a small water leak in a faulty hydro dam can develop to a torrent and take a structure down, so also can heat buildup damage the insulation layer in a cell and cause an electrical short. The temperature can quickly reach 500°C (932°F), at which point the cell catches fire or explodes. This thermal runaway that occurs is known as “venting with flame.” “Rapid disassembly” is the preferred term by the battery industry.

 

[Bopop4]

I'm sure I told you that?



Ah yes.

You can punch out at 250.

I just tried this evening,

How?