Doppler shift gives you radial speed relative to the satellite. ie, a hypothetical plane flying a curved track along the 40 degree contour would have zero doppler shift (and constant ping time.) Nobody thinks a curved track was flown by 9M-MRO.

The combination of changing ping time and doppler gives further information, but does not appear to be sufficient to identify a single location without assumptions about speed, fuel, and altitude.

It's all going into a mathematical model. When some of the assumptions (variables in the equation) change, the results change.

Ping Circles
 

If the last 3 ping circles are known, then assuming reasonably constant speed, altitude and direction, there will be 3 equidistant intersecting points along the actual path which can be found on those circles.

No need for doppler measurements.

Anyone see a problem with this geometrical method?

The consequences of the laws of physics can sometimes be counterintuitive.

Faster does not necessarily mean further.

In nil wind conditions, any airspeed above the aircraft's best range speed will result in shorter range.

Much faster equals much shorter.

time and position
 

Are we REALLY even certain of that? (Considering it was a primary target only)

Regardless , we are assuming that there was fuel available at 08:11 :ugh:

Fuel exhaustion is not a given. Maybe the aircraft arrived at the desired destination...

Olasek,

I agree the SATCOM makers who ever they are being Rockwell Collins, Honeywell, etc, will know the reason and the logic behind that last partial ping. We don't know yet. Let's hope they have an answer and are being called upon by the investigation team...

buttrick (03:47):

Quote:

---

01:30 02:11 18:11 First of seven automated hourly Classic Aero pings (handshakes) (since last ACARS transmission) via the Inmarsat-3 F1

---

From the published chart the six "pings" before the 00:11 read on the chart at:
~18:25, ~18:28, 19:40, 20:40, 21:40 and 22:40. They are not every hour, as written everywhere:
http://www.straitstimes.com/sites/st...325/graphe.jpg

Is any body have an idea why there are 3 pings in about five minutes around the time the plane ("possibly") turn south?

OK a bit speculative but not pure!
It would be exactly the sort of consequence of the gennys going off-line and RAT or APU coming on line.

time and position
 

I'm really questioning the primary returns at GIVAL and IGREX ( the NW, "avoid" Indonesia route). Any coorborating evidence? (Could the Indonesian military radar been asleep also?)

you have right to question anything you want, nothing is 100% official appart from disappearing of this plane.
But I think you have to be reasonable. Every piece of info, every map analyzing possible tracks shows all tracks converging at IGREX, this seems to be an undisputed origination point for the tracks heading South. I haven't seen any mention that it could still be disputed.

I disagree.
They just had a plane and 239 people disappear on their watch. Despite the fact that no physical evidence has been found, the Malaysian President said the plane is destroyed and all the passengers are dead. A profoundly disturbing conclusion like this needs a better explanation than "oh some clever satellite guys in England worked it out."
They have a duty to explain this conclusion in excruciating detail, not just morally, but legally under agreements signed under the auspices of the ICAO.

Personally, I don't doubt the conclusion that the a/c is somewhere in the Indian Ocean, but I am starting to doubt the Malaysian authorities competence and commitment to transparency in this investigation.

I believe the RAT won't power the SATCOM terminal, but the APU presumably would.

No problem, Mises, but there are an infinite number of solutions to it.

To buttrick and the others that are still having difficulties understanding how, if the plane was at a higher speed, the crash location would be closer to Malaysia:

If the plane travelled faster, then it would have achieved less range. This is a well known fact of aerodynamics. The laws governing this reality are the same as those for your car. Try driving somewhere at 100 until you run out of fuel. Then, try again at a speed of 80. You will get further along the road at 80.

So, at the higher speed, the plane covered less distance. Therefore, the crash point is closer to Malaysia than originally calculated. So the crash point would still be on the 40 degree arc, but at a point further up - which is a point to the northeast of the original area - which is exactly how they have moved the search area.

99.99% would not understand the explanation, and because of that would claim conspiracy, including the most 'vocal' victims.

Under ICAO charter they have to eventually come up with the report, there is no duty to stand in front of some hysterical crowd
and play psychologist and mathematician at the same time.

What is missing is that some people are married to the idea of time being known, constant, this is a mirage, at best we know elapsed time of this flight +/- 20 mins.

I would claim reverse - there is a PR machine to give those few 'hystericals' more credence than they deserve and discounting families of other passengers.

Have they?

I think the only thing that has changed is where around the 40° arc they are searching.

Speculation about the speed the aircraft may have been traveling and when is just an irrelevant furphy (primary radar speculation withstanding) until the black boxes are found.

Glen

Holding multiple press conferences makes you a target.

I think what Amsa are doing releasing multiple updates, charts and photos via the internet plus the raaf pilots bad pollies found media conferences has kept everyone in the loop, even when large changed occur.

Just my HO.

In practical terms, I suspect that the 'pings' happened every 30 minutes, i.e. 11 and 41. My question would be, "Where are the missing 'pings'? Did they not fit the expected Doppler.

In relation to the 18:25 and 18:28 graphed points, there is no straight forward explanation, but may be the cockpit SatPhone has been used??

Same elapsed time - 6 hours from last radar return (if not bogus)

But don't forget, you'd need a dog on the 4th seat just in case the retired Captain decides to go postal with the Taser.
I'm glad this thread has degenerated to a level whereby all commonsense, reason and useful facts are no longer being submitted.
I wonder why I stopped reading this a while back, and now I know.
When you have 'members' who are clearly not professional flight crew clogging up pages because they can't understand how you can travel less distance when cruising at a higher speed, you have to wonder.

Let's hope the ongoing search can reveal a few facts, then perhaps 99% of the posts by Mar2014 joiners can be eradicated to remove a lot of the uneducated bullcr@p.

I'll give this post 5 mins.