Originally Posted by
antonen
first ping was before the plane disappeared, so at least 1 ping has real coordinates. Maybe even second can be assigned with the help of military data.
Inmarsat have not (AFAIK) released information about any 'pings' other than the final one. Before the data source (ACARS, transponder, other) was disabled, what the aircraft (presumably) sent to the satellite was not just a "ping" but a proper telemetry message.
Even so, any satellite-based range information obtained before the transponder was disabled or ground-based radar lost track of the aircraft is redundant information. ATC and/or the radar tells us "the plane was
exactly at this point at this time" while a 'ping' at the same time tells us "the plane was on a circle X km from the sub-satellite point" where the circle includes the exact point known from ATC/radar.
None of that tells us whether the plane flew north or south after ATC/radar lost track of the plane.
Originally Posted by
antonen
Yes, this can be true, but if we assume the plane was going circles. Does the planes usually fly that? I think it's reasonable to consider that the plane continued flying along established routes, then the ping data will help a lot. Of course it may be wrong, but then, it's better than searching whole Indian ocean. Then we can assume it was flying straight - this will be tougher, but again possible to calculate. Once again, it really depends on the ping data. They can really show nothing but there's not 0% possibility they will be a great help. I can't see the reason for not making this info available to public.
No, planes don't
usually fly like that, but pilots don't
usually turn off the transponder, or make a sharp turn off the scheduled course, or fly a zig-zag path after that, or fly to 45,000 feet and then drop to 23,000 feet. MH370 is known (or suspected) to have done those things.
We are not talking about a normal flight. It is already clear that either the pilot was flying an unpredictable route to avoid detection or the flight was erratic for other reasons.
If the plane was on the northern route and under intelligent control, there is quite reasonable speculation that the pilot was flying close to the terrain, which would involve more zig-zagging to use terrain as well as trying to avoid population centers which might have radar. It may also (maybe
CaptainMiles or another pilot can help us) mean it was flying somewhat slower than the ideal cruising speed.
If it was on the southern route and under intelligent control, it looks like someone was planning to ditch in the ocean. It's not obvious that one needs to fly as far as possible in a straight line to achieve that.
In short, I don't think you can assume the plane took a straight line at a constant speed after the last radar contact.
Originally Posted by
antonen
if we are speaking about a theoretical Mathemathical question you're absolutely correct. But in real life possibilities like flying 200 kph or 1200 kph or touching down and then taking off are not very likely imho.
No, of course it can't fly at very low or very high speeds, but I assume that the speed is variable within a range (
CaptainMiles can you help here?) and ground speed varies with wind speed as well as load, as
CM already explained. And the plane was "missing" for 5 or 6 hours between the last radar contact and the final 'ping', it is not completely impossible that it touched down somewhere; it could have even stopped at a point on the final 'ping' arc close to where it went missing and stayed there sending 'ping's until 0811.
Originally Posted by
cassiewoofer
Yes I know there are problems but if taken for a purpose of a long flight by a human with a distant intended destination it is almost certain it would be straight and at cruising speed. Unless he's got plenty of fuel to spare and is not in a hurry.
But what if his intended destination was not "distant"? He could have flown a non-linear complicated route to avoid radar, knowing he had fuel to spare and not being in a hurry, to get to a point somewhere between KL and the end points of the ping 'arc'. If he had a hidden base in, Bhutan, for example, he didn't have to fly that far to get there.
Or again, it might not have been a deliberate plan; there may have been an inexperienced (unexperienced?) pilot at the controls who couldn't keep a straight course, or there could have been damage to the aircraft controls or navigation system that made keeping a straight course impossible.