[Peetwo]

No pong about the pings! - Let the search continue.

Yes "V" excellent post...

I have a question for you in regards to:

A number of pilots have postulated that:-

(a) the flight was deliberate and
(b) the flight was under pilot "management" and "control" until the end, and
© that end was a ditching.

Q/ In regards to (a) & (b), does your view/theory entertain the possibility that MH370 may have been under control to TOPD then with flameout of LH engine 'person(s) in control' have nosed over into steep dive prior to RH engine flameout, RAT auto-deployment & APU auto-start (in time to transmit 00:11UTC ISAT ping).  So hitting the water controlled, much like Germanwings A320 into the foot of the French ALPs?

I know that brings into question the matter of debris dispersal (or lack of), but as it was pointed out by Mick & John at post #232, it is conceivable that debris would have drifted many miles from the impact point by the time the SIO SAR had begun.

One thing from the rubbish article from News Corp that I think is significant, was the comment from Mr Mimi on the one bit of evidence that could ultimately prove/disprove the many "cruise portion" theories:

Commissioner Dolan said the ATSB was still awaiting the outcome of a French investigation into the flaperon confirmed as coming from MH370.

“At this stage we’ve not heard anything from the French that would enable us to form a view about what position the flaperon was in when it separated from the aircraft which is the key question for us,” he said. “It’s quite possible we won’t get anything definitive on that.”

Malaysia is also due to release another report on the anniversary of the plane’s disappearance, en route from Kuala Lumpur to Beijing.

“We’re still waiting to understand what it is that they’re intending to publish, said Mr Dolan.

“That’s up to them.”

   
From experience with this individual, when he says "anything definitive" is code for "hopefully never", therefore he feels vulnerable about what the French may ultimately reveal.

Coincidentally back to the Oz where the subject of the flaperon also gets discussed:

David

@Brendan Footnote. Suspect I am firing this into thin air, but in case anyone is there, why the flaperon detached is, I understand, under investigation by the French. Not that obvious because it is attached at four strong points and the Bailey theory that if might have been taken off by a separated engine seems unlikely because it does not display that sort of impact damage. Shame this investigation is incomplete (or its results not made public) because it might well throw light on the aircraft's last moments, in turn confirming search priorities or otherwise.

Mick

@David  David, you're correct. Captain Bailey has previously stated that Boeing had stated that the flaperon had "been broken off in a lowered position".   Boeing have made no such statement, they have examined the flaperon but only to the extent required to identify the part number.    The flaperon is still in the possession of the French authorities.

Have a look at the underwater pictures from the Air France AF447 crash; one wing is shown completely stripped of aileron, inner and outer flaps.

David

@Mick @David Thanks Mick. Air France hit the water fast. MH370 not so fast?
Probably left spiral, right flaperon. DuncanSteel com archives 2026 refers to Tom Kenyon's flaperon failure study of Oct last year, on Dropbox. His 1933 refers to others and also ocean drift analysis. Curious silence about this, months later. 

Mick

@David   Thanks David, that's a very, very interesting report, I hadn't seen it before.  Very interesting conclusion:

"Repetitive lateral or torsion forces appear most likely at this stage of the analysis. This conclusion, combined with the lack of strong secondary evidence of a trailing edge strike, infers that the disengagement occurred while MH370 was in flight."

That pretty well torpedoes the good Captain's claim that "the flaperon is an integral part of the wing and would not be broken off separately unless it were lowered."
 
I think MH370 would have had a higher speed impact than AF447 which hit the water about 10,000 feet per minute or just under 200 km/h.  I think some of the simulations for MH370 suggest it may have exceeded its design envelope during the descent, exceeding 1,000 km/h.

David

@Mick @David  My first response now revised.  Yes I have now seen Air France was quite slow and nose up in the stall though with high descent rate. Maybe even tougher on the wing fittings. Unclear to me where in the flaperon report he got info on evidence of fatigue from and it will be interesting to see what the French find. 

It would be odd should the French not have been in consultation with Boeing since they will have all the stressing and test data.I hope they talk or Malaysia facilitates and something definitive is forthcoming shortly.

&..

Mick

@Rod Mmm, I really can't comment on the underwater locator beacon other than to say that it is not an integral part of the CVR or FDR, it is attached and its survivability rate is only 90%, when we heard the pings it was right towards the end of the normal operating life for one of those bits of kit, and the detection range is 5 kilometres under ideal conditions down to 1 kilometre in rough seas so you pretty well got to be right over the thing to be able to localise it, especially with one one detector (eg one ship) . 


The floating wreckage is always going to be a matter of conjecture.  Bear in mind that we weren't looking anywhere near close to the right spot until some three weeks after the actual crash; 10 days were wasted looking in the Gulf of Thailand and Andaman Sea and then we spent the best part of another 10 days looking way to the south and west of where we should have been (that was largely because we didn't get the refined INMARSAT analysis and interpretation until around about day 18 after the crash).


Without wanting to sound trite, it's a big ocean, complex currents, bounded by a lot of relatively remote and/or lightly trafficked coastline.   Add the complexity associated with what floats and for how long and under what circumstances and you've got one lowish probability layered upon another layered upon another ...    Why the flaperon?   If you look at the underwater pictures from the Air France AF447 crash you'll see that one of the wings is pretty well devoid of control surfaces, the ailerons and inner and outer flaps were all gone.   Depending on the damage sustained in the crash, the control surfaces are pretty good candidates to float and float the longest and be easily recognised if they are ever found - they are sealed, light, have good structural integrity and being "wing-shaped",  even to the casual observer, they look "aeronautical".



Rod


So from what I can gather the engines receive fuel from three tanks - one in each wing, a right or left centre tank and a shared centre tank. There is then no auxiliary tank which needs to be switched on either automatically or manually, the latter method requiring the hand of a living, breathing pilot, in order to exhaust the fuel supply.


A course was set for one of the remotest parts of the world such that, even if the plane had substantially broken up on impact, there would be little likelihood of finding debris. The theory that the pilot himself was responsible for this outcome seems plausible to me. His motive is lees clear as is the timing of his death.


As an interested member of the public I resent being told that we have pings, pings come from the plane but, guess what, there is no plane even to this day. I think Mick that even you have some trouble with this.



David



@Rod Unfamiliar with what you mean by the third ping Rod. There was a ping apparently detected (HMS Hero?) which proved to be a sonar fault. To add one point to Mick, it has been found that the pinger battery life was out of date I think so it may not have had normal oomph anyway. 



Rod



My recollection is that Angus Houston announced that there were enough pings to locate the plane but it is quite some time ago and further information about ping reliability may have come to light.



Mick



@Rod 

I can't recall Houston saying that (they never localised the pings with any precision).

I'm pretty sure that there were 5 "pings" picked up in total. 


On 5 April 2014 (day 30), a towed pinger locator detected two sets of underwater pulses of a frequency close to that used by the underwater locator beacons (ULBs).  The ULBs emit an ultrasonic 10 millisecond ping once per second at 37.5 kHz ± 1kHz; the battrey has a 30 day life at 4°C temperature.  At the depth the wreckage would have sunk to in that part of the Indian Ocean woukd have been colder than 4°C so getting 30 days out of batteries would have been unlikely. Also, the pings detected were outside the ± 1kHz range but there are some underwater phenomena that could account the frequency shift.


On 8 April the off-frequency pings were briefly reacquired twice.  The signals weren't localised and they were about 27 kilometres from the 5 April detection.

A fifth detection on 10 April by a sonobuoy dropped from an Orion, was way off frequency and not proximal to the other four and was deemed unlikely to be related to a ULB.


As David points out above the 8 April detection was put down to an equipment fault. Maybe that's where the third ping comes in - 5 in total, 2 eliminated leaves 3 - but that would make the sonobuoy ping, the least reliable, the third ping.

Riddle, mystery, enigma.



Rod



Good to know there is no pong about the pings! Let the search continue.........



Andrew



@Rod  Expanding on Mick's comments above re the fuel system, there are essentially three tanks; left and right main tanks and a centre tank.  The centre tank on the 777-200ER is essentially one big tank that feeds both engines.  Part of the centre tank is located in the left and right wing roots, just inboard of the engines, with the rest located in the centre wing section inside the fuselage.  There is no auxiliary tank.



The fuel system operation is automatic.  Fuel is normally used from the centre tank first, to supply both engines.  When the centre tank is empty, the left and right main tanks automatically supply the left and right engines respectively.  Fuel can be cross-fed from one side to the other, but that selection must be made manually and would normally only be done in the event of a fuel imbalance.



Re the 'pings', there were three sets of acoustic detections.  The first, by HMS Echo, was discounted as it was caused by the ship's own sonar equipment.  The second, by the Chinese ship MV Haixun 01, was discounted after analysis revealed the detections were unlikely due to the ocean depth, surface noise and the type of equipment that was used.  A submarine that was tasked to the same area was unable to get any detections.  The third set of detections, by Australian Defence Vessel Ocean Shield, could not be repeated when the ship was tracking in the opposite direction.  Independent analyses of the Ocean Shield detections determined that they were not consistent with the acoustic beacons fitted to MH370.  Nevertheless, an underwater sonar survey of the area was undertaken using an autonomous underwater vehicle about a week later, but nothing was located. 

MTF...P2