Menu Sign In Contact FAQ
Banner
Welcome to our forums

MH370

I am leaning towards a catastrophic failure, such as a fire particularly in the avionics bay, nose gear bay or pressurization pack. It is difficult to explain the reported temporary climb to FL450 unless there was a fight for control in the cockpit or some sort of catastrophic failure. Some have advanced a theory that it was to kill off the passengers, but this makes absolutely no sense. According to available data on the 777, it maintains a cabin pressure differential of 8.5 psi. At 35000 feet, the outside pressure is 3.2 psi and the cabin altitude is just over 5000 feet. At 45000 feet, the pressure is just under 2.1 psi and the cabin would be at 7700 feet. Either won’t kill off the passengers. On the other hand, people would not survive long exposure at either 35000 feet or 45000 feet, so if the pilot was going to dump the cabin pressure to kill off the passengers, a climb is totally unnecessary. Part of the fire procedure can involve turning off one of the service packs or other equipment and rapidly descending. Also, remaining at 45000 feet would be difficult at best as the spread between supersonic flight involving mach tuck or a stall is around 10 knots. The service ceiling is listed at just over 43000 feet, but probably not that high when the airplane is heavy with fuel.

If it was a suicide mission, why would the airplane continue for so long? One might as well get it over with. A crew that was incapacitated would fly on until fuel ran out if the autopilot remained in control.

KUZA, United States

The altitude reports after the txp was turned off are very unclear.

Can any primary radar system get that resolution from possibly a few hundred nm away?

Administrator
Shoreham EGKA, United Kingdom

Can any primary radar system get that resolution from possibly a few hundred nm away?

Yes, military radar could do that already in 1968 (when I did my compulsory military service with the airforce).

Last Edited by nobbi at 21 Mar 19:34
EDxx, Germany

How does it do that?

The angular resolution needed would be far higher than what is achieved using civilian radar today.

For example modern ATC radar is accurate in azimuth to something like 1nm at 50nm range i.e. 1 part in 50. Obviously this is not a problem with traffic separation because that is done relatively, but it means your GPS is far more accurate in determining whether you are busting some CAS boundary than ATC radar if located some tens of nm away. I have seen this a number of times and on one occasion I recall I had a discussion with them afterwards and they told me they can’t really tell to better than 1nm (at 30nm in that case) so they tell people they are busting even if they show 1nm outside.

Now, in altitude terms, 1 part in 50 is equivalent to 6000ft at 50nm, which is rubbish. To get the figures talked about e.g. 5000ft, FL450, FL295, one would need 10x to 100x better accuracy. I am not saying it isn’t possible, but how does it work?

Administrator
Shoreham EGKA, United Kingdom

I remember something about radar accuracy like that, actually managed to manifest itself and cause an operational discussion.

On a trip somewhere with multiple a/c in our group I was passing just outside a zone and had an exchange with the controller where he didn’t chastise me, but just told me that I was showing slightly inside his zone and was henceforth cleared if that’s where I wanted to be. I replied thanking him for the clearance and advising that our certified GPS showed us outside the zone.

Later in conversation with others in the group, there was a bit of head-shaking. A couple of folks with a lot of experience said things like “I’ll take his multi-million pound radar over your GPS” and generally tut-tutted a lot. I was the only scientist in the group. I tried to explain about azimuth, range, resolution, and the relative absolute accuracy of the two technologies, but the non-scientists just didn’t want to hear it. I think their reasoning was that I was wrong, and I had to be wrong because I was a PPL and the other guy was a professional ATCO. I just shook my head and gave up.

EGLM & EGTN

I am not saying it isn’t possible, but how does it work?

I have no idea – it must be a matter of wave length, antenna diameter, certain impulse technology, sheer power output ? And it is different to ATC Radar …

http://www.radartutorial.eu/02.basics/rp13.en.html

EDxx, Germany

The other possibility would be simply to note how far away the aircraft was when it appeared over the horizon – would give you the altitude.

How many people here think that “doppler” could be used to distinguish between the northern arc and the southern arc?

It is a simple symmetrical case no matter which way you look at it. There is no way to tell.

Would they have logged the very small frequency shift caused by the aircraft flying south the northern arc versus flying south the southern arc (for which there would be a different shift)?

Last Edited by Peter at 24 Mar 21:34
Administrator
Shoreham EGKA, United Kingdom

I read somewhere that after the turn West, the aircraft tracked directly along the border of the airspace between Malaysian and Thai airspace at 29500 ft. For that reason alone, I think this was a hijack.

Peter, are you referring to this
Last Edited by JasonC at 24 Mar 23:06
EGTK Oxford
Sign in to add your message

Back to Top