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

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Bopop4
You can punch out at 250.
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What are you talking about? Punch out is a term for the use of ejection devices. They are not fitted to passenger aircraft, apart from Bond's.

Bopop4
How?
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PDMG in FSX. I can tell you it perfectly replicates my time in a Boeing 777 simulator and that the aero simulation in particular is very good.

You could actually work the figures that I gave you out for yourself; you already seem to know that V2 (sea level) is around 160kias so you'd expect to be trimmed slightly nose-up with flaps. To say that you'd fly it level or stable at 8,000feet at that speed (or closer to 200kias as you said later) without flaps is incredible. You then accepted you'd go up to 250kias as I advised.

I said that you might be able to get out of door 3, but you can not use flaps doing that, you'll definitely be blown up to the tail plane.

Next time you're on the m-way put your hand out of the window at 40mph, 80mph and 120mph. The pressure difference is not linear. 100mph is around the max speed you'll leave your Cessna at, but it's more likely closer to 70mph (incidentally the speed that lift aero effects really start to curve up!) for safety reasons (got to make sure you miss that tailplane!). There's 2m between you and that tailplane.

There's about 20m between you and the Boeing tailplane, but you're doing 290mph. That's the 70mph zone + 220mph. Parp.
 
TenEightyOne
(got to make sure you miss that tailplane!). There's 2m between you and that tailplane.

There's about 20m between you and the Boeing tailplane, but you're doing 290mph. That's the 70mph zone + 220mph. Parp.
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There is no way to hit the tail in level flight in a small aircraft, one of the testing criteria is someone trying to hit the tail.
If you're going 100mph and you jump and try to hit a tail 2m away, then someone trying to not hit a tail ten times the distance at triple the speed isn't going to hit either.



(For the record I think the plane just had a catastrophic failure and it crashed in the ocean and sank.)
 
Re: Lithium Batteries - There's been a recent uplift in the IATA standards for shipping lithium batteries and it is no less a minefield than it was before.

I would note however that lithium batteries can be packaged within their product in most circumstances. So we're not necessarily considering just individually packaged cells/batteries.

However, I really hope it's not lithium batteries that caused an issue, because it's getting tough to transport them as it is.
 
There are reports that the captain received a two-minute phone call just before takeoff from an unidentified woman using a pre-paid phone that has not been used before or since. The reports go on to suggest that the caller used a false identity, as under Malaysian law, anyone purchasing a pre-paid phone must register it with their passport number.

But I cannot follow the source of any of these stories back further than a tabloid rag.
 
Bopop4
Again, one of the certifications for a parachute approved aircraft is testers trying to hit the tail.
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In Canada, or in general? Got a link for that?

If someone does something stupid, (Or like that link says, "Innovative".) then you could kill yourself with the tail.
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Bopop4
There is no way to hit the tail in level flight in a small aircraft...
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These two things cannot both be true. Either there is no way to hit the tail of a small aircraft, or it's possible if you do just the right (wrong) thing, in that particular case jumping upwards as you exit.

It's probably possible to calculate whether someone would get close to the tailplane mathematically in a similar way to the article I linked in my last post, given the dimensions of the aircraft, the airspeed, the air pressure and a reasonably maximum approximation of the aerodynamic drag of a person.

Seems like it's more work than it's worth though, when as @TenEightyOne says they could just choose another door, one without the possibility of sudden catastrophic death if they did their math wrong.
 
@Bopop4 @TenEightyOne
@Imari

I calculated the tail hit scenario for various airspeeds at an altitude 8000 feet and a distance to tail of 20 meters. The human body is of an average shape and size and weighs 80 kg.

First I needed to calculate how fast a body is decellerating when jumping from an airplane. At the moment of jumping it's travelling at the same speed as the airplane, but is quickly decellerated by the drag from the air.

So here's the first graph, showing how much time it takes before the decelleration of the body causes the tail of the plane to pass overhead (hopefully it'll be overhead and not on-head...)

777_1.jpg


So at 700 km/h it takes 0,68 seconds before the distance between tail and body is 0 meters.
At 450 km/h it takes 0,89 seconds.

So now when we know how much time the body has to fall before the tail would pass, we can calculate how far it would have dropped.

777_2.jpg


At 700 km/h the body would have dropped about 2,3 meters by the time the tail passes.
At 450 km/h the body would have dropped about 3,9 meters.


7773.jpg


So it looks like it would be possible to jump and miss the tail. Of course, turbulence is a big question mark in these calculations, I'd imagine there's quite a lot of it at those speeds and they might just as well push the body over the tail... It also depends on the shape of your body when you jump. If you're shaped like an airfoil, your body might create lift at those speeds, counter-acting gravity.

It would also be a chocking experience to jump at those speeds. When jumping at 700 km/h, the air resistance would decellerate the body by an initial force of 8.7 G. At 450 km/h, it would be 3.6 G.

For comparison, when parachuting from a Cessna at 70 mph the G forces from wind resistance is about 0.2 G.
 
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Imari
In Canada, or in general? Got a link for that?
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An ex-parachute instructor actually told me that.
I would assume FAA standards regulate it. (Or something along those lines.)

Imari
These two things cannot both be true. Either there is no way to hit the tail of a small aircraft, or it's possible if you do just the right (wrong) thing, in that particular case jumping upwards as you exit.
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The "wrong" thing would be something like climbing onto the wing and then jumping, or climbing up onto the aircraft etc.
Jumping out the door or from the struts you shouldn't be able to hit.

eran0004
...
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Yay math.

I will say that when you get up to 700km/h, you might get sucked into the slipstream from the fuselage, and end up getting knocked out. (Hence the term "riveting", because you bounce along the aircraft's rivets.:lol:)

I remember watching a video where an F-15 pilot had to bail at somewhere around mach 1. He lived but basically broke his face.
 
eran0004
MATH
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Nice work.

Seems like in level flight you'd miss, but not by much, assuming no weird aero effects like the slipstream Bopop mentions.

Put a bit of angle on the aircraft and you're probably bone-diddley-owned.

Bopop4
The "wrong" thing would be something like climbing onto the wing and then jumping, or climbing up onto the aircraft etc.
Jumping out the door or from the struts you shouldn't be able to hit.
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The math in the first link I gave you says otherwise, not to mention the guy who died, and then there's stuff like this:

http://www.totalinjury.com/blog/skydiving-center-found-not-liable-for-jumper’s-injuries/

So it's clearly possible. I'd agree with you that if proper procedure is followed it would be near impossible, but it doesn't seem like it takes much of someone showing off by trying to do a stylee move or something out the door to make it really pretty close. Certainly not something as obvious as climbing the struts, anyway.
 
Great maths, @eran0004 :D

3.6g on leaving, ouch! Presumably you couldn't jump straight out, you'd need to 'slide' around the rear edge of the door so you weren't bashed to death on the way out... then push away if you're able. As @lmari said the margin's still quite tight though.

@prisonermonkeys, I'd just seen the story about the "Captain's mystery phone call". It's not impossible but he'd presumably have had an unregistered mobile too... at least that was my first thought.

BBC
"Malaysian police have dismissed as mere speculation a report by the UK's Daily Mail newspaper that the captain of Flight MH370 received a call shortly before take-off from a woman using a mobile phone number obtained under a false identity, [/URL]according to The Star Online. A spokeswoman was quoted as saying the information "originates from unnamed and unverified sources".
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That's all I can find on it.

Going back to thoughts about Li-ion batteries, I asked an electrical engineer who designs packs for field equipment, he said one big nightmare for racks of them is damp. I asked what could make a brand-new stored battery pack just go up, he said moisture or manfuacturing defect. They have to be stored and transported properly, no doubt the company responsible for the shipment would have ensured that all safety advice was given and followed, but what if some warehouse shortcut led to them being left overnight in the dew and starting a short that didn't reach a critical point until the aircraft was in flight? You could theoretically have a large, hot, localised fire in the belly of the aircraft without any of the timeline warnings associated with a fire of a more 'normal' profile.

The fire theory has fallen out of favour now given that the plane appears to have changed course before the last routine radio message... but I'm not sure of any fact right now ;)

EDIT: Just watching coverage of the Aussie search, they're dropping GPS locators at the edge of their search envelope to try to figure out what the currents are doing out there. They're not so green as they're cabbage looking!
 
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No @Imari, @TenEightyOne, and @eran0004 you guys are very wrong. First off @Bopop4 knows and he knows because he watched...IRON MAN 3 and the scene where IM saves the people from Airforce One proves that they jumped. /close thread.

On a serious note, has no one brought up the French supposedly finding stuff or did I already forget that I saw it...
 
TenEightyOne
I said that you might be able to get out of door 3, but you can not use flaps doing that, you'll definitely be blown up to the tail plane.
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Wings blow air down, not up, the flow off the wing will probably help you clear the tail. Still, as you said there are better exits.
 
Exorcet
Wings blow air down, not up, the flow off the wing will probably help you clear the tail. Still, as you said there are better exits.
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It's a pretty turbulent business, might as well push you up. And as you're not travelling with the windflow but rather against it (if you jump at 450 km/h you'd still be going at an airspeed of 280 km/h by the time the tail passes) your body would be an airfoil and wether it will lift you up or push you down would be purely down to chance as I don't think you'll be able to control your body much when facing such forces. I mean, it's equal to a category 5 hurricane when you pass the tail, and twice that when you leave the plane.

If you decide to jump I wouldn't give you better odds than 50/50.

Of course, potential hijackers may not have done the math and just thought that it would be like parachuting off any plane. What you're not aware of you can't be afraid of.
 
prisonermonkeys
The Chinese have reportedly found "suspicious objects" floating ~850km from the current search zone.
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Source?

Anyway, HMAS Success is nearing the site of two large objects seen in the water, in the next few hours. Hopefully that will bring something conclusive.
 
Exorcet
Wings blow air down, not up, the flow off the wing will probably help you clear the tail. Still, as you said there are better exits.
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Yes, with the flaps retracted you'd actually get a bit of help going downwards. Once you lower flaps you'd hit the new overflow that misses the wing and blows over the fuselage to the tail (777 deploys surface aft and for'd of the wing). Mincemeat time. :)

OT: The Beeb also seeming to increase in confidence with reports of debris. They report more ships/planes moving into the area to try to find reported debris, including "square orange object", "round grey or green object". Hmmm....

Squidward-3-spongebob-squarepants-23418080-500-289.gif
 
I get the feeling that if this doesn't turn out to be MH370, then the plane may be lost forever. They have been quickly and gradually narrowing down the search area over the past few days, but if this turns out to be nothing, then they will have nowhere to go from here.
 
prisonermonkeys
I get the feeling that if this doesn't turn out to be MH370, then the plane may be lost forever.
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There is only so many places it can be and if it is not found by thre search party, it will be found later in the future when they do deep sea mapping and they end up finding the wreckage.
 
Grayfox
There is only so many places it can be and if it is not found by thre search party, it will be found later in the future when they do deep sea mapping and they end up finding the wreckage.
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Presuming that it is lost at sea (which I agree is still the most likely scenario) then it will only be 'easily' findable as long as it remains on the surface of the sea bed. In deeper areas we know very little about the nature of the terrain surface. AF was only found because of the most insanely dedicated ongoing search attempt. The odds of it ever having been found otherwise would, in my opinion, have been very very low.

@prisonermonkeys These searches are all based (afaik) on satellite imaging returns, either photographic or other. I suspect that potentially-significant returns will keep cropping up and be as credible as the current ones. Finding things floating about isn't unusual and as the debris field drifts over time so the area from which 'hits' need to be considered increases.

Sadly this stops when someone makes the decision that it stops.
 
TenEightyOne
Presuming that it is lost at sea (which I agree is still the most likely scenario) then it will only be 'easily' findable as long as it remains on the surface of the sea bed. In deeper areas we know very little about the nature of the terrain surface. AF was only found because of the most insanely dedicated ongoing search attempt. The odds of it ever having been found otherwise would, in my opinion, have been very very low.
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At depth, the sea floor is mostly quite flat, and if the plane went down by a water "landing" rather than a hard impact, then the pieces would should be big enough to spot using shipboard bathymetric scanning equipment.
 
TenEightyOne
Presuming that it is lost at sea (which I agree is still the most likely scenario) then it will only be 'easily' findable as long as it remains on the surface of the sea bed. In deeper areas we know very little about the nature of the terrain surface.
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Pray it didn't go too deep...
hXe2DvA.jpg
 
eran0004
It's a pretty turbulent business, might as well push you up.
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If the air you're flying through is relatively calm, the turbulence is only confined to a few specific areas, though one of those would be along the fuselage. While the wake of the wing contains turbulence, most of the air it's affecting won't have much.


If you decide to jump I wouldn't give you better odds than 50/50.
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I don't really know what the chance of success would be, but I think the flaps may actually help.

TenEightyOne
Yes, with the flaps retracted you'd actually get a bit of help going downwards. Once you lower flaps you'd hit the new overflow that misses the wing and blows over the fuselage to the tail (777 deploys surface aft and for'd of the wing). Mincemeat time. :)
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Are there no levels of deflection which only deploy the trailing edge surfaces? Though even if there is separation off the wing, it would tend to be slower and/or lower in total pressure which would actually help with the massive deceleration issue.

Maybe if you looked really deep into this it might work, but it still wouldn't be as good as going out the back.
 
Barra333
At depth, the sea floor is mostly quite flat, and if the plane went down by a water "landing" rather than a hard impact, then the pieces would should be big enough to spot using shipboard bathymetric scanning equipment.
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Semi-buoyant objects on flat areas tend to make their way to deeper areas as they get wafted along. Technical term, obviously :) . That's not the case if they sink into silt but silt itself isn't necessarily static. Big pieces will stay pretty much as they are in any case, so you're quite right about that.

I'm surprised the Americans haven't found something yet, a 777's only 75% of the size of an Akula but with a larger plan area.

@Exorcet, actually there are, the initial stages are trailing-edge only iirc, you wouldn't go beyond the first two 'stops' above 220kias. The aircraft flies the same way in stable flight at 8000ft but takes longer to react to inputs and is harder to keep stable. I think the chances of finding a good jump configuration are so tough that you might as well just go out of the cargo hatch, like we keep saying :D

@Dotini , I need to look at some of the technical claims in there, the 45,000 feet climb seems to be something that is recognised to have happened. That's from sources additional to the FlightTracker which, in itself, just looks laggy and incorrect to me.

They're correct that the service ceiling is 43,000 feet (give or take a pigeon) but the plane can climb quite a bit higher by accelerating at a lower altitude then zoom-climbing. The pilots need to be ready to guide the plane back down at the top of the arc, this is a manouver that one would only perform in testing or a genuine emergency. I wasn't sure that pilots would do this to try to extinguish a fire but I've read accounts from a number of pilots saying that they would consider it feasible although they're not aware of it having been carried out in real life. So I stand corrected on that.

EDIT: Be wary of statements that say "The pilots cannot...". That's true in normal operation mode but any number of things can be done by someone who wants to sabotage a flight. This is especially true of claims about switching systems off.

Here's one of the ELTs, mounted in the FDR that is in a rack forward of the rear pressure bulkead. Two minutes' work to unplug and, if you wish, destroy.

cfkha8tal274wq0uu.jpg
 
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Yikes, sounds like they've found the plane.

@BillNeelyNBC: Message from Malaysia Airlines
"We deeply regret that we have to assume beyond any reasonable doubt that MH370 has been lost"
 

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