APU bleed air max altitude is 22000' for 777

etrang
 

But the timeline for when that information, if it exists, was made available is not clear.

The fact that the aircraft may have been pinging periodically for up yo four hours is the flight timeline, not the SAR timeline.

Malaysians 'muppets', etrang? To quote you,
Yes, one example of why the Malaysians face such a challenging situation, as time and again supposedly 'reliable' sources, including sources from outside Malaysia, have proved to be misleading and contradictory. If the US 'knew' where the plane is, they would have told everyone by now and the mystery would have been resolved. None of us can know for sure, but press conferences aside, I can see no reason not to think they are doing the best job they can in the circumstances.

If the information is correct that they received pings for 5 hours it might be a valid assumption that the aircraft continued until the engines flamed out. Obviously one of the scenarios could have been a successful ditching and a bunch of life rafts floating somewhere.

If a buss problem occurred, and took out 1 IDG, the busses tie and takes out the second. APU is off so your down to the emergency generator ( that can't carry the whole plane) and the battery powered backup...

If the event was caused by a hull breech and for some reason the pilots didn't get on O2 fast enough you would lose a lot from the load shed, and would start losing more as the radios dropped out do to low buss voltage.

I know..longshot. But just because the APU Is supposed to start at service ceiling doesn't mean this one would.

RE ACARS- PINGS- TRACKING
 

FROM WSJ . . ." The automatic pings, or attempts to link up with satellites operated by Inmarsat PLC, occurred a number of times after Flight 370's last verified position, the people briefed on the situation said, indicating that at least through those five hours, the Boeing Co. BA -2.04% 777 carrying 239 people remained intact and hadn't been destroyed in a crash, act of sabotage or explosion.

Malaysia Airlines said it hadn't received any such data. According to Boeing, the plane's manufacturer, the airline didn't purchase a package through Boeing to monitor its airplanes' data through the satellite system."

IMO- there is a lot of confusion re pings and data by most of the media

depending on whom you believe

1) MA did not buy the online- enroute maint package- therefore pings may only had or RR only received takeoff and climb and mayberf level off data- thus the " no data " after xxx comment

2) The simple pings may only contain altitude and speed data- triangulation by sigint or other satellites may reveal course

3) The difference in time between Acars data and turnoff of transponder may be simply due to ACARS time intervals re pinging

4) Its doubtful the Pentagon would re route a destroyer/ship AND P8 without a bit more positive info than reported

5) actions re shutoff of systems seem to be deliberate- rule out explosion

6) IF deliberate - why not fly to deepwater and dive in - no claims by any group will have greater longterm effect ( re cost $$$$$ and unknown FUD ) than simply saying ' we did it "

7) On a $$$ cost basis, the 911 was very effective and made a major change in air travel and security costs

8 ) almost any-every indication and analysis seem to indicate a deliberate action by ?????

(9) AD re corossion is a non starter as is my post about future tie in of FBW and entertainment systems PLANNED BUT NOT YET IMPLEMENTED-

JUST MHO- FWIW

slats11
 

But human intervention is not the same thing as system failure.

From a security point of view, which is my field, preventing human intervention is whole different ballgame from making systems more reliable and less prone to failure.

The only way to stop a human intervening and doing something they shouldn't is to totally lock the human out of the equation. So the pilot would be rendered a complete spectator and would, therefore, be completely superfluous.

Not quite. Any receiver will also broadcast an intermediate frequency at very low power. Detecting this is how radar detector detectors work, and it is also how the television tax police in UK and France track down folks with TVs who aren't paying their TV tax. None of this helps find a GPS receiver somewhere over the ocean though. The latest news on ACARS data is quite interesting.

Or landed somewhere. Or ditched before the engines flamed out and floated for a while.

Impressions on Press Conference
 

Over the course of the week, we've seen the Malaysians hold several press conferences. As we are not privy to what goes on behind the scenes to the actual SAR work, we can only draw the efficacy of their operations from these media events.

IMHO, they started the press conferences like deer caught in headlights, but are getting better. I think they have revealed what they are sure of, and were cautious with unconfirmed information at hand. Military secrecy is not unique to them, and I was suprised that earlier press conferences involved a couple of generals. If unlawful acts were considered, it is understandable that leads were not publicised straight out. They have been consistent in saying the priority is to find the plane, and I believe this is matched by what they do on the ground (well, at sea & in the air, rather).

But being in the limelight is clearly not their thing. To make matters worse, those on the podium try to communicate in English, only a second language in Malaysia. They were hesitant, clumsy and uncoordinated. And so we judge their whole operation by what we see there.

Everyone is frustrated with the lack of progress. It is all too easy to place blame as a way to vent.

"Seafloor event" possibly linked to MH370: Chinese researchers
2014-03-14 13:15:46

BEIJING, March 14 (Xinhua) -- Chinese researchers have detected a "seafloor event" near the waters between Malaysia and Vietnam, an area suspected to be linked with the missing Malaysian jetliner MH370, a university announced on Friday.

The event occurred at about 2:55 a.m. local time on Saturday, about one and a half hours after the plane's last definitive sighting on civilian radar.

The area, 116 km northeast from where the last contact with the Boeing plane was recorded, used to be a non-seismic region, according to a research group on seismology and physics of the earth's interior under the University of Science and Technology of China.

The seafloor event could have been caused by the plane possibly plunging into the sea, the research group said.

"Seafloor event" possibly linked to MH370: Chinese researchers - Xinhua | English.news.cn

It is also possible that the US Government has military capability that they do not want to talk about publicly. In other words, the data sent by Boeing is simple "I'm alive" data for non-subscribers to its service but that USA spy satellites intercept such data and store the location of the source on the fly. So Boeing doesn't know where the plane is or was but the military does, and its taken bureaucratic shuffling to get that data to the SAR people.

One can imagine a scenario, where decompression did not occur, but comms and nav became permanently disabled and command authority in cockpit by design or circumstance was left to the autopilot. Then manual authority in the cockpit was eventually regained so there was manual input or control when it touched down/crashed in the sea.

In such a scenario, a very, very, very slim chance of the latter phase of the flight ending well enough that there are survivors currently languishing on escape slides that are not fitted with even an off the shelf $200 EPIRB.

Satcom Phones
 

In response to an earlier post, I flew in an MH 772 recently and can confirm that it was NOT fitted with a Satcom Phone system.

GPS Receiver inside Cell Phones/Smartphones
 

Many smartphones include GPS functionality, but this is usually disabled to conserve power.

Presumably, there is an "NSA" function allowing the operator to turn on the GPS of a cell phone on a network.

Separately, cell phones are automatically located (by triangulation among towers) whenever they join a network cell.

MAS and the Malaysian authorities are not the source of truth for these transmissions that they are denying exist.

http://www.theaustralian.com.au/news...-1226854490107

Meanwhile the Chinese May have another theory;

From MalaysiaKini ( behind a paywall so I've cut and pasted)


The search for the missing Malaysia Airlines Flight MH370 appears to be shifting back and forth between east and west of peninsula Malaysia, with latest information from scientists in China suggesting that the plane may have triggered a seismic event when it impacted the sea some 150km off the southern tip of Vietnam.

A team of seismologists at a top China research university said they detected a slight seismic event on the sea floor between Vietnam and Malaysia on March 8 which could be a result of an impact.

"It was a non-seismic zone, therefore judging from the time and location of the event, it might be related to the missing MH370 flight," said a statement posted on the University of Science and Technology of China website.

This was also reported by the South China Morning Post.

This comes as US officials begin to set their eyes in the Indian Ocean after almost a week of futile search in the South China Sea, citing indications that the plane may have turned around after losing communication and flown on westwards for several hours.

If you're thinking Doppler/Doppler shift might cause problems then is it worth considering what happens to the shift when you are near the overhead of the cell phone tower?

I have evidence that it is definitely possible to receive "welcome to" text messages in the cruise at or above FL350 (remote part of the world, flying at more than M 0.80). No idea if a voice or text "out" would work and I'm not going to experiment.

What MK is saying is that cellphones at altitude work better when few or a single tower is in reach, because no frequency interference. There is plenty of evidence showing that cellphones work in airplanes at surpringly high altitudes. Work in the sense they register with the network not that they are useable.

Jimmy the con said:

"To suggest that the aircraft is currently holed up on a remote island is laughable."

I would suggest that a qualified pilot holding full back stick whilst attempting to recover from a stall...is even more laughable.

But it happened!

I figure you'll know what I'm talking about.