MH370 - "new" news
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After reviewing the primary radar recording, the turn back was most likely at a standard 25 degree angle of bank left turn.
Failing someone for diverting to the NEAREST SUITABLE AIRPORT seems harsh.
The loss of transponder, ACARS, radio communications, Flight ID, and diverting to an airport is consistent with an onboard emergency.
Failing someone for diverting to the NEAREST SUITABLE AIRPORT seems harsh.
The loss of transponder, ACARS, radio communications, Flight ID, and diverting to an airport is consistent with an onboard emergency.
We know that MH370 had both engines operating normally, a fuel system operating normally, a flight control system operating normally, a navigation system operating normally, a Satcom system operating normally; which included means to communicate any emergency should all other comms be down.
So the turn towards Malaysia, if you really believe Penang was the goal; (it wasn't), would still take a few minutes at the very minimum to happen and would not be the very first response. Penang also had a curfew which the Captain would be aware of. You also haven't explained why they didn't land there but managed to fly for more 6 hours in a straight line to the SIO which can only be accomplished with an operating and programmed FMC (LNAV) or an operating and correctly set Autoflight system. (True TRK)
Q. Hamid was the PF. Who flew the initial turn and how do you know?
How do we know? The primary radar recordings.
The turn back was not commenced immediately, it was a few minutes later after the “event”. This is still consistent with an accident scenario.
Q. What altitude and speed would you fly at towards Penang, following an oxygen bottle rupture with a damaged P105?
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Penang may have been the nearest option, but not by a significant amount. A few minutes flying time.
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Who flew the initial turn towards Penang? As stated previously, the 25 degree angle of bank left turn was conducted manually by someone in the cockpit, or via the autopilot in heading mode.
How do we know? The primary radar recordings.
The turn back was not commenced immediately, it was a few minutes later after the “event”. This is still consistent with an accident scenario.
Q. What altitude and speed would you fly at towards Penang, following an oxygen bottle rupture with a damaged P105?
How do we know? The primary radar recordings.
The turn back was not commenced immediately, it was a few minutes later after the “event”. This is still consistent with an accident scenario.
Q. What altitude and speed would you fly at towards Penang, following an oxygen bottle rupture with a damaged P105?
Is the aircraft losing pressurisation? If so is it a rapid depressurisation?
Evidently not, due to the TAS values of the entire subsequent track.
MH370 was travelling at normal, or slight faster TAS values until it crashed in the SIO. The track into the SIO was programmed by the FMC or the available autopilot modes. We know that because it flew a straight line to the south.
The turn back was initiated just after the transponder was turned off from the flight-deck. That is known from the transmissions received from the transponder as the knob was turned through the various options available, to the “OFF” position.
I’ve have given you a list of the major systems that are known to have been operating for the entire flight. There is no indication of any malfunction.
You haven’t responded to the straight line of the track. I suspect you don’t know the significance of that and why it means there was someone actively flying the aircraft.
You have an unsupported theory. Nothing more.
Last edited by Capt Kremin; 19th Jan 2023 at 11:40.
Capt Kremin, thanks for your reply.
You say, “The track into the SIO was programmed by the FMC or the available autopilot modes. We know that because it flew a straight line to the south.”
What flightpath and endpoint are you proposing?
Do you know what happens when a B777 flown on autopilot in LNAV, encounters an end of route, whilst tracking south on the last leg?
You say, “The track into the SIO was programmed by the FMC or the available autopilot modes. We know that because it flew a straight line to the south.”
What flightpath and endpoint are you proposing?
Do you know what happens when a B777 flown on autopilot in LNAV, encounters an end of route, whilst tracking south on the last leg?
For example, if the transponder loses the air data input from the AIMS cabinet, it will be unable to transmit that data. Monitoring will then disable the transponder.
The left transponder is usually the primary transponder.
The air data for the left transponder is from the left AIMS cabinet.
The left AIMS cabinet is next to the oxygen bottle.
The left transponder is NOT situated near the oxygen bottle.
The oxygen bottle was repressurised prior to flight.
An oxygen bottle rupture would cause extensive damage to the P105 left wire integration panel/left AIMS Cabinet.
An outside observer cannot determine the lack of transponder returns was due to the transponder being turned OFF manually (at a slower than normal speed) or due to a failure.
It is unknown why the Prime Minister of Malaysia reported the lack of transponder returns was ONLY due to it being switched off. This comment, along with the multitude of other misinformation being spruiked, deflected the blame from the Malaysian Government (accident scenario) onto a scapegoat pilot (hijack scenario) unable to defend himself.
For example, if the transponder loses the air data input from the AIMS cabinet, it will be unable to transmit that data. Monitoring will then disable the transponder.
An outside observer cannot determine the lack of transponder returns was due to the transponder being turned OFF manually (at a slower than normal speed) or due to a failure.
Ah GBO, you clearly missed the point Capt Kremlin was making, the switch design and functions on the way to off.
Perhaps I should ask you, which is the NORMAL in flight position, from your experience flying?
Perhaps I should ask you, which is the NORMAL in flight position, from your experience flying?
Not necessarily. The "primary" transponder is whichever transponder is selected (ie L or R) during the preflight. That selection is airline dependent. At Malaysian, the SOP (as stated in their OPS-A) was to select the L transponder on outbound flights from KUL and the R transponder on inbound flights to KUL. In this case, the L transponder should have been selected given that MH370 departed from KUL.
The transponders receive air data from BOTH AIMS cabinets. The L transponder receives ADIRU data from the L AIMS cabinet on ADC Input1, and SAARU data from the R AIMS cabinet on ADC Input 2. The R transponder receives SAARU data from the R AIMS cabinet on ADC Input 1, and ADIRU data from the L AIMS cabinet on ADC Input 2.
The air data for the left transponder is from the left AIMS cabinet.
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Q. What flight-path and endpoint are you proposing?
A: Easy, PPOS-99SP
Q. Do you know what happens when a B777 flown on autopilot in LNAV, encounters an end of route, whilst tracking south on the last leg?
As I posted before, stop feeding the troll. If you don't feed him, they'll get bored and go away.
We know from the data that the last two ADS-B transmissions received from MH370 (at 17:20:34.15 and 17:20:34.55 UTC) didn't have altitude data. There was subsequently some speculation that the absence of that altitude data may have been because the transponder was, at those times, in a mode that would suppress the transmission of said data, specifically ALT OFF.
It was noted that the ALT OFF position on the Transponder Mode Selector sits between STBY and the normal operating mode position, TA/RA. There was then further speculation that the process of manually moving the Transponder Mode Selector knob from TA/RA to STBY would cause the transponder to go into ALT OFF mode as the selector passed through that switch position.
Stitching all of that together, some observers contend that the ADS-B data shows that transponder must have been switched off manually.
A couple of things are worth noting. The physical process of turning the Transponder Mode Selector knob through 135° from TA/RA to STBY takes about 0.35 seconds, a bit less if the act is performed with a sense of purpose. The dwell time in the ALT OFF position is consequently fleeting, <0.1 seconds. To the best of my knowledge, nobody has actually checked whether the switch reader would even register that as a mode change.
Similarly, again to the best of my knowledge, there hasn't been much of an effort put into understanding the processing logic that sits under that mode selector switch. Once the switch has read a mode change, the processing logic will be such that different routines are commanded. In there somewhere will be instructions for what data needs to be be packaged and handed off for transmission. It would be useful to understand how that works.
And an understanding of basic processing times and latency would be needed to resolve the problem of timing. ADS-B transmits every 0.5 seconds, give or take. The physical act of turning the transponder off takes less than that. It would be an extraordinary piece of timing for the fleeting transition to ALT OFF to have been read and the data package for next ADS-B transmissions to have been amended accordingly before the final mode position, STBY, is read and the transponder responds by ceasing to transmit.
The missing altitude data may be an indication that the transponder was manually turned off but that is currently just speculation. Speculative interpretations being commonplace on this particular topic, I am sure that nobody is surprised that some other observers point to the exact same ADS-B data as being evidence of some sort of cascading system failure whereby altitude data was lost just prior to the transponder failing.
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Good points, all of which are easily testable. I’m surprised that test has not occurred.
And GBO’s claim that loss of air data input to the Left transponder, as a result of the loss of air data from the left AIMS cabinet alone, would result in the monitoring system automatically disabling all Left transponder functions, is easily testable. If true, I’d suggest it’s not a sensible design. It’s like ‘disabling’ a life raft because its emergency torch doesn’t work.
And GBO’s claim that loss of air data input to the Left transponder, as a result of the loss of air data from the left AIMS cabinet alone, would result in the monitoring system automatically disabling all Left transponder functions, is easily testable. If true, I’d suggest it’s not a sensible design. It’s like ‘disabling’ a life raft because its emergency torch doesn’t work.
