MH370 - New Development

[dutchroll]

Thanks.. and whats the duration of the pilot o2 on a 772ER ?

It's not possible to give an exact answer to that.

Pilot oxygen mask regulators in all Boeing and Airbus aircraft are "on demand" regulators, not fixed flow regulators like the passenger ones.

 

The FAR requirement is for a 10 minute minimum crew oxygen supply (I think). It's really only supposed to get you down to a breathable altitude. I would suggest about 15 minutes max would be a reasonable guess, unless you switched it off 100%. But with varying respiratory rates and workload, who knows what it will last? Probably not a heck of a lot longer than that at a typical cruise altitude, judging on how it drops during the preflight check.

 

The cockpit also has portable oxygen bottles which we can plug into.

 

We also get an alert if the flight crew oxygen pressure gets too low.

 

 

[facthunter]

Just a bit of general stuff on oxygen/altitude . The normal cabin is kept at around 8,000 ft. Even that will affect some people who are not very fit. A fit person will stay conscious at around 23,000 for quite a while but that will be widely variable with the individual. If you live at high altitudes you adapt a lot over time. At modern cruise levels of 40,000 ft plus you won't stay conscious for very long at all without oxygen which is often diluted with air Demand system. Pure oxygen is not good for you if used for long periods, though we used to use it for hangovers whether it did much, I don't know. Nev

 

 

[dutchroll]

The more I click on the links to the other MH370 theories out there (I seriously need to stop doing that), the more dumbfounded I get. I'm starting to understand why most current commercial airline pilots who fly Boeing and Airbus jets are not commenting in any great numbers.

 

You can't fight them. Even if you say "the system doesn't actually work that way" or "that's not how we operate the aircraft", the theory doesn't really change but just gets squished and stretched to a slightly different shape.

 

Like the oxy bottle failure theory. It totally ignores the fact we get a prominent warning on main display screens of any flight crew oxygen system failure, including a readout of the current oxygen system pressure which is displayed at all times. And it ignores the fact that if that we also have portable, self contained oxygen bottles the same as the ones in the cabin, but with an attachment on the bottle to directly plug our cockpit oxygen masks into.

 

The jet appears to have been programmed to take it on a course to where, once it ran out of fuel, it would be most difficult to ever find (though I bet they never imagined how successful they'd be). No terrorist organisation ever claimed responsibility. So someone wanted to die and they didn't care that everyone else would too. I seriously doubt anyone was alive on it for most of that flight.

 

 

[facthunter]

If the pressurisation system wasn't working the plane's temperature would fairly rapidly become so low the passengers would be frozen solid, (same as happened with the Greek airliner) .Long before that they would have died of hypoxia. IF someone had an extended supply of oxygen It wouldn't stop them freezing.

 

 

[onetrack]

The ATSB has apparently had an initial examination of the so-called "MH370 burnt debris" items found by Blaine Gibson, and brought to Australia by him.

 

They have determined that;

 

A: It cannot yet be proved that the items comes from MH370. Their statement was, (the investigators have) "found no manufacturing identifiers such as part numbers or serial numbers that provided clues as to the items' origin".

 

B. It appears the markings on the material, that were identified as a dark grey colouration on most of both sides of the items, were due to "an applied resin and was not the result of exposure to heat or fire".

 

It was further stated, that there was, "no evidence of overall gross heat damage".

 

So, despite Gibsons excitement, and widely reported claim that the items had been burnt, and could quite likely be from MH370, it appears he's wrong on all counts. Back to the search, Mr. Gibson!

 

MH370: No evidence 'debris' exposed to fire, officials say

 

 

[dutchroll]

....I don't find that surprising at all!

 

But that's just a real bummer for the "kept flying for 7 hours after a catastrophic fire" theorists!

 

 

[facthunter]

Your range would be significantly less at lower levels. Depressurising saves fuel also. Just for those who want more to speculate with. The captain would know all that. Nev

 

 

[onetrack]

One part that continually puzzles me, is that the MH370 wreckage continually turns up at Mauritius or Madagascar, and the surrounding regions. Now, the entire West Australian coast has 1100 known shipwrecks along its length.

 

Quite a number are local shipwrecks - but a sizeable number are sailing ship wrecks - and they were all blown ashore by the prevailing strong South-Westerly and Southerly winds, that are feature of the W.A. coast.

 

Only during the extreme height of Summer (Jan-Feb), does the wind (in the lower latitudes) occasionally alter to a strong Easterly that blows out to sea - but it doesn't usually last long, or go out to sea very far.

 

In general, if something lands in the sea to the West of W.A., below about the latitude of roughly, say Shark Bay/Denham, the item will eventually wash up on the West Australian coast.

 

However, if an item ends up in the sea off the coast North of Shark Bay/Denham - and particularly during the cyclone season (Nov-May), the trade winds above this latitude at that time of year are strong - and they're prevailing strong Easterlies.

 

As a result, items lost in the sea from this area above Shark Bay/Denham, quite often end up on the East Coast of Africa. There was a case of a bloke who lost a boat off Exmouth in 2013 - and it turned up at Madagascar, 8 mths later!

 

http://www.perthnow.com.au/news/western-australia/lost-wa-boat-found-7400km-away-in-madagascar-after-eight-months/story-fnhocxo3-1226795703739

 

Then there was also the case of the Carley float from HMAS Sydney - which was sunk in November 1941, about 200kms West of Carnarvon, found washed up, on the shores of Christmas Island in February 1942.

 

What I am getting at, is the combination of not one single item from MH370 being found on the W.A. coast - yet items from MH370 being found on the East Coast of Africa - indicates to me that MH370 went down, a lot further North than the ATSB has calculated.

 

Then we have the corresponding indicator, that not one single item of any kind from MH370, has been found since the ATSB initiated the Fugro-led search operation.

 

Not only have Fugro been combing the supposed crash area for around 2 years, the Australian Govt also carried out an Indian Ocean sea bed mapping operation, prior to the Fugro ships starting their search.

 

This apparently had to be done, because there had been no previous accurate sea-bed mapping done in the region, and the Fugro ships would have otherwise been doing the equivalent of setting off on a flight without charts.

 

So, we have had an absolutely vast amount of trawling of the selected search area, and still not a single item has been found. They even found an 18th or 19th century, previously-unknown shipwreck - but they still have not located a skerrick of wreckage from MH370.

 

The accumulating evidence is either that the ATSB's fuel-burn calculations are wrong, and they are searching in the wrong place - or the wreckage of MH370 fell into an underwater canyon, which they have missed.

 

One would believe, that Fugro is a very professional and skilled operation, and they haven't missed very much at all - unless they have set their equipment to scan too rapidly and too widely.

 

However, you'd expect that a hull the size of a B777 would surely show up on any reasonably-well-done sonar sweep, sticking out like the proverbial sore thumb.

 

 

[facthunter]

It's a big area to cover and no doubt some deep canyons. The prevailing ocean currents may provide clues rather than surface winds. Nev

 

 

[dutchroll]

However, you'd expect that a hull the size of a B777 would surely show up on any reasonably-well-done sonar sweep, sticking out like the proverbial sore thumb.

Yeah I think they're probably looking in the wrong area and there is some error in the estimated endurance.

It's just that I don't have the faintest clue where the right area is!

 

It is a "needle in a haystack" search though. With Air France they knew exactly what its planned route was and had a lot more to go on, including the time stamping of the barrage of automated ACARS messages they received when it had the air data computer problems. Still took them a year to find it (and I sure am glad they did because the airline industry learned some enormous lessons from that investigation).

 

 

[Birdseye]

This old map has appeared in Wikipedia and a number of MH370 articles and clearly shows how debris would generally move on the ocean currents. Wind would only have very localised effects, bar the Monsoonal changes in the northern Indian Ocean.

 

 

 

[onetrack]

Wind would have a substantial input to the travel direction of wreckage if it projected above the water line. The average current is around 1-3kts, wind is regularly around 10-15kts - and it gusts to a lot more.

 

All the old VOC ships that fell victim to the W.A. reefs and cliffs, were driven onto the W.A. shoreline, or the Abrohlos Islands, every time, by the prevailing winds.

 

The old Dutch ships captains knew that they could get to Batavia (Java) in record time by travelling in the "Roaring 40's" latitudes - and they all knew they had to be very alert to being driven onto the W.A. coast, and to turn North early, to stop that from happening.

 

William Dampier, the Englishman, knew about all the VOC shipwrecks, and he was super-cautious about running into the Abrohlos Islands or the W.A. coast, and made sure he turned North early on his 1699 voyage, and very carefully avoided Dirk Hartog Island at Shark Bay, where he was at risk of being driven aground constantly as he tried to get around the island and into Shark Bay.

 

The ocean current map above is a bit "dodgy". It shows an unmarked current off the W.A. coast, running S to N - but the reality is, the Leeuwin Current is what is just offshore from W.A., and it runs from N to S - with a number of eddys a little further offshore.

 

Further West, well offshore, the West Australian Current is the stronger current, but only during Summer, when the Leeuwin Current weakens. In Summer, the West Australian Current is known to bring flotsam and jetsam onto the W.A. coast.

 

http://www.oceanclimatechange.org.au/content/images/uploads/Australia_oceans_fig1.jpg

 

 

[Birdseye]

Yes I'm sure you are right. <Yawn>

 

 

[vixen]

Onetrack:

 

Old galleons would have got blown East with their hull and sail areas easily, for sure.

 

However with MH370 I think you are assuming that the 777 hull floated.

 

I doubt it floated at all. Even if it ditched successfully (which is highly unlikely) it would not have floated for long. Hence the currents would surely be the dictator, not the winds?

 

Would the prevailing currents have brought it to WA, based roughly on the current search area?

 

Cheers

 

 

[onetrack]

No, no - I wasn't intimating the hull or any huge component floated. I know as well as anyone else, when an aircraft hits water at speed, it shatters. Water is nearly the equivalent of concrete when you hit it with substantial velocity.

 

We have the AF447 wreckage to give us the proof of what happens when a large commercial jet goes into the open ocean.

 

The engines break free, but largely stay intact, wings are broken into many small pieces, the tail is ripped off, and the fuselage breaks up into sections.

 

However, the larger portions of the wings, the elevators, the tailplane and the VS are quite likely to float (due to their honeycomb structure, or compartments that are effectively sealed), and have enough surface area exposed to the wind to affect their direction of travel.

 

I've seen an article where the investigation experts are trying to figure out, with improved accuracy, just how much the drift of wreckage is governed by currents, and just how much is governed by the wind (can't recall where it was now).

 

They were doing calculations on the amount of exposed surface area regularly above the water, versus the amount of surface area constantly in the water, to try and determine the forces and direction.

 

It appeared to be that it didn't take a lot of area exposed above the water (even if that area was flat), for the items direction to be driven more by the wind, than by the current.

 

The problem with trying to figure out the direction of currents, is the regular number of eddies in the ocean, even within known strong currents.

 

However, the likes of the prevailing winds to the West and South West of Australia are reasonably constant, and the movement of the weather patterns below the Tropic of Capricorn is constantly Eastwards.

 

MH370: Aircraft Debris and Drift Modelling

 

 

[tafisama]

If it hit water at high speed they might need to at the Acoustic hydrophone signals again from Curtain University.Maybe the actual location is perpendicular to the assumed track.I believe its more North and probably west.

 

 

[ben87r]

DR (and other WB drivers), do they have any indication of what altitude it maintained? And how much effect would it have had if they were say 4-6k' above or below planned cruise on range?

 

 

[dutchroll]

I don't think they had any indication of altitude after it went outside radar and VHF coverage (I can't see how they'd get one if they weren't datalinked by satcom).

 

2000 ft above optimum cruise = 2.5% penalty

 

1000 ft below optimum cruise = 1.5% penalty

 

4000 ft below optimum cruise = 5% penalty

 

That's in an Airbus. I don't have a B777 FCOM but it gives an indication of what sort of penalties you're looking at.

 

 

[facthunter]

Unless someone's resetting stuff, there's not much scope for it to wander around the sky. It has to have a reference for the A/Pilot, usually "alt hold" as it cruises with a clearance based on a set "level". and if you don't lose power it's OK. You have very little margin for a change of Airspeed or Mach No as the "boundaries" are not far apart especially at highest recommended flight levels, which used to be referred to as "Coffin Corner" where the VMo/ MMo lines come closer together. As fuel burn takes place, a higher level is desired for optimum cruise , but that's a question of efficiency not a safety issue unless your range is critical. Nev

 

 

[Robbo]

The thing is on the FMS you have Perth/Penang in close proximity (in the menu) if you are suffering hypoxia or from smoke inhalation you are that dazed and seeing double vision you could easily hit Perth and off to Perth you go, until the plane is destroyed by fire or runs out of fuel and crashes in the ocean.

 

 

[dutchroll]

Not sure I understand what you mean by this. Where are Perth and Penang in close proximity in which menu on a Honeywell (standard Boeing) FMC?

 

To get to a new waypoint or destination you have to type either the ICAO designator in, or the navaid identifier. If you type in a navaid identifier for Penang VOR, you would type VPG. The only list you'll get is any other identifiers around the world which are VPG, and their distance from your current position. Perth VOR is PH.

 

Or if you typed the airfield in, you'd have to type WMKP for Penang, or YPPH for Perth. That won't give you a choice at all because ICAO designators are unique but navaid identifiers are not.

 

 

[Robbo]

Not sure I understand what you mean by this. Where are Perth and Penang in close proximity in which menu on a Honeywell (standard Boeing) FMC?To get to a new waypoint or destination you have to type either the ICAO designator in, or the navaid identifier. If you type in a navaid identifier for Penang VOR, you would type VPG. The only list you'll get is any other identifiers around the world which are VPG, and their distance from your current position. Perth VOR is PH.

 

Or if you typed the airfield in, you'd have to type WMKP for Penang, or YPPH for Perth. That won't give you a choice at all because ICAO designators are unique but navaid identifiers are not.

There is an option to get into a screen with quick access, cannot remember exactly on how to find it but it allows to create quick access way points, like favorites on your computer, maybe I am thinking of a different FMS but there is an option in one of them, forget how I got into it but I was shown it by someone and there words were "hardly anyone knows you can do this"

 

Not sure if anyone uses the menu, but will check it out when I can and make sure I am not thinking of something else.

 

 

[dutchroll]

Yeah you can type in quick access waypoints in the fix pages, or just type them in the scratchpad and line-select them into the legs page, or change your destination.

 

But the only syntax a Honeywell FMC (and the Airbus is the same) recognises is ICAO 4 letter identifier, or the navaid identifier. Type in PE and all it will do is pop up the list of identifiers, respective current distances from them, and corresponding navaid frequency, in its database which are "PE", neither of which are Penang or Perth. You then have to choose the one you want, which is 99.99% of the time the closest one.

 

Even I know Penang is WMKP. A Malaysian pilot would certainly know it. If they wanted Penang they'd type (for a Boeing) WMKP into the scratchpad, line select it to 1L, confirm it, then the flying pilot would say "execute", the non flying pilot would press the illuminated EXEC (execute) button and it would load into the navigation legs as the next waypoint.

 

 

[vixen]

I already stated I don't buy "The Captain dun it" theory.

 

Why would he kill 100's coz he was a bit peed off with the politics in Malaysia?

 

And/or where was his history of insanity, a la the German Wings FO?

 

I could go on. Suffice it to say - It doesn't have enough evidence to assert such imo. If there is please enlighten me?

 

I have never supported any conspiracy theories.

 

However, in this case I suggest we should be considering UMNO racketeers as a possibility.

 

A well planned suicide operative could have done this - and brilliantly (in a vile way) made it look like it was the Skipper.

 

And I suggest more than a few wildcard nutters in the UMNO tentacles thought they had good motive to do so.

 

A bit Hollywood??? ... yea I used to think like that... until 9/11

 

"Fact can be stranger than fiction" ?

 

Cheers

 

 

[Robbo]

Sadly, I think in 100 years the children of our childrens children will be talking about this.

 

It will be like a long lost ship wreck.