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Missing MH370: Expert Needed to Disable B777 Systems
Malaysia Star ^ | 3/15

Posted on 03/15/2014 2:24:35 PM PDT by nickcarraway

If multiple communication systems aboard Flight 370 were manually disabled, as investigators increasingly suspect happened, it would have required detailed knowledge of the long-range Boeing777's inner workings.

The Wall Street Journal said the first loss of the jet's transponder, which communicates the jet's position, speed and call sign to air traffic control radar, would require disabling a circuit breaker above and behind an overhead panel.

Pilots rarely, if ever, need to access the circuit breakers, which are reserved for maintenance personnel.

Pulling one specific circuit breaker, which is labeled, would render inoperative both of the 777's transponders, according to documents reviewed by WSJ and bolstered by comments from aviation industry officials and those who have worked with the 777.

Becoming familiar with the 777's systems requires extensive training for pilots and aircraft mechanics alike, experts said. However, considerable technical data on the airplane is also available online in discussion groups or other websites.

Investigators are trying to establish a sequence of events that transpired on the jet, which vanished from radar March 8, most critically the loss of communication.

The shutdown of the on board reporting system shortly after the jet was last seen on radar, can be performed in a series of keystrokes on either of the cockpit's two flight management computers in the cockpit.

The computers are used to set the performance of the engines on takeoff, plan the route, as well as other functions to guide the 777.

After vanishing, the jet's satellite communications system continued to ping orbiting satellites for at least five hours.

The pings ceased at a point over the Indian Ocean, while the aircraft was at a normal cruise altitude, say two people familiar with the jet's last known position.

Investigators are trying to understand that loss, and whether or not "something catastrophic happened or someone switched off" the satellite communication system, says one of the people.

The longest week

A physical disconnection of the satellite communications system would require extremely detailed knowledge of the aircraft, its internal structure and its systems.

The satellite data system is spread across the aircraft and disabling it would require physical access to key components.

Disconnecting the satellite data system from the jet's central computer, known as AIMS, would disable its transmission. The central computer can be reached from inside the jet while it is flying, but its whereabouts would have to be known by someone deeply familiar with the 777.

Getting into the area housing the 777's computers would "not take a lot" of knowledge, said an aviation professional who has worked with the 777.

However, this person added, "to know what to do there to disable" systems would require considerable understanding of the jet's inner workings.

Some airlines outfit the access hatch to the area below the floor with a special screw to prevent unauthorized intrusion, the person added.

Orbiting satellites are designed to check in with the aircraft's satellite-communication system hourly if no data is received during that time.

The pings from the aircraft became a subject of scrutiny earlier this week, said a person familiar with the matter, several days after the plane first went missing.

Because the pings between the satellite and the aircraft registered that the aircraft's satellite communications system was healthy and able to transmit, the data did not immediately raise any red flags in the hours after the jet's disappearance.

At first, the origin of the final ping from the Malaysia Airlines jet seemed like an anomaly to investigators, according to a person familiar with the matter, given that the plane was believed to have crashed off the coast of Vietnam, hundreds if not thousands of miles from the location of the final ping.

What is a transponder? Until just a few years ago, the satellite communication system used by jetliners didn't include data on an aircraft's location in the pings, the electronic equivalent of handshakes used to establish initial contact.

For instance, before Air France Flight 447 crashed into the Atlantic Ocean in 2009, the jet sent some diagnostic data indicating problems with various onboard systems, including the autopilot's deactivation. But notably the plane's position wasn't transmitted with that data.

Partly as a result it took nearly two years to locate the plane's "black boxes" and the majority of the wreckage. In the case of the missing Malaysian jetliner, precise locations were provided. However, it is unclear why the transmission ceased and where the plane may have ended up after the final ping.

An expert would be needed to disable the systems on the missing Malaysia Airlines jet. The headline to an earlier version of this story incorrectly said an insider would be needed.


TOPICS: Extended News; Foreign Affairs; News/Current Events
KEYWORDS: boeing; malaysia; mh370
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1 posted on 03/15/2014 2:24:35 PM PDT by nickcarraway
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To: nickcarraway

At first I thought with the number of people with cellphones on the plane someone would call for help. But then I remembered there are electronic devices which disable cell phones ability to make/receive calls that are readily available and cheap.


2 posted on 03/15/2014 2:31:31 PM PDT by BipolarBob
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To: nickcarraway
An expert would be needed to disable the systems on the missing Malaysia Airlines jet.

There are several wrong statements in this story but this is a fact.

3 posted on 03/15/2014 2:33:38 PM PDT by zipper ("The Second Amendment IS my carry permit!" -- Ted Nugent)
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To: BipolarBob

I think a bigger problem is that cellphones go out of range. Once they are off-shore, and 20 or 30 miles from a celltower, they do not work.

Some have commented on how phones worked during 9/11. That’s not relevant here, because the 9/11 plane paths were entirely over land, where cell towers are plentiful.


4 posted on 03/15/2014 2:37:06 PM PDT by Pearls Before Swine
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To: nickcarraway

Presumably there are bound manuals onboard that tell you have to disable most anything. In the case of an electrical short/fire in a given system you would need these instructions. With some planning you wouldn’t need to fumble with a four inch think binder, but a single peace of paper with only those exact instructions or you could memorize the fuse panel location, fuse locations, sizes and/or slot numbers.


5 posted on 03/15/2014 2:39:00 PM PDT by Fitzy_888 ("ownership society")
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To: nickcarraway

Bookmark


6 posted on 03/15/2014 2:40:08 PM PDT by BunnySlippers (I LOVE BULL MARKETS . . .)
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To: nickcarraway
...its whereabouts would have to be known by someone deeply familiar with the 777.

If someone wants to steal something, they can do the research.

7 posted on 03/15/2014 2:42:22 PM PDT by Libloather (Embrace the suck)
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To: BipolarBob

Is it possible to jam the transponder signal without actually turning off the equipment?


8 posted on 03/15/2014 2:43:50 PM PDT by smokingfrog ( sleep with one eye open (<o> ---)
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To: nickcarraway

Why are the systems made available to the crew in such a way that they can be disabled? What’s the real world, legitimate reason for crew disabling these systems?


9 posted on 03/15/2014 2:45:43 PM PDT by andyk (I have sworn...eternal hostility against every form of tyranny over the mind of man.)
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To: nickcarraway
"Pilots rarely, if ever, need to access the circuit breakers, which are reserved for maintenance personnel."

Seems simple enough. Were all maintenance personnel accounted for or is it being covered up?

10 posted on 03/15/2014 2:47:46 PM PDT by Karl Spooner
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To: BipolarBob

If the plane was over the ocean when it went to 45,000 feet (IMO as part of a plan to decompress the cabin and kill the passengers), the plane would have been out of cell phone range. I think this was a sick but well-conceived theft of the plane by either the pilot, co-pilot or a crew member who had access to the cockpit.


11 posted on 03/15/2014 2:48:02 PM PDT by dirtboy
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To: andyk

“What’s the real world, legitimate reason for crew disabling these systems?”

Electrical problems. Shorts. Fires.

You’d want to be able to shut them down in cases like this.


12 posted on 03/15/2014 2:49:32 PM PDT by FAA
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To: FAA

The transponder too? Seems like that logic could extend to shutting down the black box. Thanks for the reply :)


13 posted on 03/15/2014 2:52:24 PM PDT by andyk (I have sworn...eternal hostility against every form of tyranny over the mind of man.)
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To: smokingfrog
Is it possible to jam the transponder signal without actually turning off the equipment?

Generally, no. You do not jam the transmitter - you jam the receiver. But the receiver is on an Iridium satellite. If you have to jam from the transmitter's position, you have to use 100 times as much power, and an antenna that is just as good - and even that may be not enough, depending on the modulation of the signal.

14 posted on 03/15/2014 2:52:27 PM PDT by Greysard
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To: nickcarraway; a fool in paradise
First word of the article:

If

Thank you too much.

15 posted on 03/15/2014 2:55:37 PM PDT by Revolting cat! (Bad things are wrong! Ice cream is delicious! We reserve the right to serve refuse to anyone!)
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To: andyk
Why are the systems made available to the crew in such a way that they can be disabled? What’s the real world, legitimate reason for crew disabling these systems?<\i>

For the ACARS it gives us the ability to reset the system if it is not functioning propey. Similar to cntr-alt-del

16 posted on 03/15/2014 2:57:14 PM PDT by ALPAPilot
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To: andyk

I’ve always heard it’s to be able kill the power so you can extinguish an electrical fire.


17 posted on 03/15/2014 3:02:35 PM PDT by ProtectOurFreedom
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To: ALPAPilot
ACARS

Heard or read .. can't remember ACARS was disabled. Or experts (dime a dozen) believe it was disabled.

18 posted on 03/15/2014 3:05:03 PM PDT by no-to-illegals (Scrutinize our government and Secure the Blessing of Freedom and Justice)
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To: nickcarraway

Have some diabolical terrorists refined the technology of ‘BAIT CARS’???


19 posted on 03/15/2014 3:06:07 PM PDT by sodpoodle (Life is prickly - carry tweezers.)
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To: Fitzy_888

I could figure it out:

http://www.hawkeyemedia.com/panos/777_Avionics.asp


20 posted on 03/15/2014 3:09:19 PM PDT by bigbob (The best way to get a bad law repealed is to enforce it strictly. Abraham Lincoln)
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To: andyk
The transponder too?

It is a transceiver, it is the cockpit, so yeah, it is good to be able to cut electrical power to something right next to you to keep it from burning.

21 posted on 03/15/2014 3:09:46 PM PDT by xone
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To: andyk

“Seems like that logic could extend to shutting down the black box”

You can. They are not “essential” for flight or proper operation of the airplane. They’re helpful and beneficial but if they’re smoking, arcing, or, otherwise interfering with the safe operation of the airplane they can be turned off.


22 posted on 03/15/2014 3:11:28 PM PDT by FAA
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To: Fitzy_888

“or someone switched off” the satellite communication system, “

Well,,,, what about the radios? I’m curious as to what communications were sent to the plane. Of course the pilots didn’t answer any radio calls, but I’d bet they were listening!


23 posted on 03/15/2014 3:22:05 PM PDT by Dr. Bogus Pachysandra ( Ya can't pick up a turd by the clean end!)
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To: bigbob
I could figure it out

Those Amphenol connectors (green, round) are poorly terminated. Some don't even have backshells or strain relief. This is not what you do in a system that experiences vibration.

24 posted on 03/15/2014 3:23:13 PM PDT by Greysard
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To: no-to-illegals

No indication that ACARS was disabled thus no expert required. Malaysia airlines does not subscribe to the ACARS so their pilots would not be familiar with it. Rolls Royce does have a subscription as part of their maintenance/support for the engines. On this flight there were three messages scheduled. One on takeoff, one upon initial cruise climb complete and one on landing. The second message was sent shortly before the aircraft diverted from plan. The third message was never received because (I assume) the aircraft never landed (crashing doesn’t count). The messages are not of immediate operational interest so they are sent at scheduled transmission windows. The SATCOM link stays active (who turns off their cable modem when they’re not watching television or surfing the Internet).


25 posted on 03/15/2014 3:23:41 PM PDT by Procyon (Decentralize, degovernmentalize, deregulate, demonopolize, decredentialize, disentitle.)
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To: Greysard

Not an Iridium satellite. Rather an Inmarsat geosynchronous satellite.


26 posted on 03/15/2014 3:25:10 PM PDT by Procyon (Decentralize, degovernmentalize, deregulate, demonopolize, decredentialize, disentitle.)
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To: zipper
Since this and their disablements are amongst our few known facts they should rapidly check the backgrounds of all on board for the needed expertise. If only the obvious two (pilot and/or co-pilot) have it the range of speculation can be narrowed. If others had it new avenues of research open.

The final recorded ping at 8:11 KL time exceeded many earlier estimates for its potential time in flight. How much fuel was really loaded and those loading it should be investigated.

Comparing the possible positions at each recorded ping (only the last has been released to my knowledge) would also be interesting. Don't know why they haven't released the others, but I can dream the plane didn't move between the last two pings so is known down, it has been spotted and Uncle Mao is en route to the rescue. Or, if it went far enough, Uncle Vlad might rescue them—he could use the PR.

Some have suspected a Malaysian coverup. The co-pilot turns out to be the son of a high ranking civil servant. Powerful fathers can run coverups. Early reports described him as "religious" and "a good muslim" contrasting his behavior inviting girls into his cockpit. While those labels may sound good for local Malaysian audiences they'd raise different issues here.

Getting to the final ping site, at least to the more interesting northern option (and who'd elaborately plan a slow suicide) means avoiding many radars. Either defenses there are much worse than presumed or the perps had the knowledge and skill to evade them. Determining what the perps could have known about those defenses and reverse engineering their possible routes may be enlightening. In the least it would be a good exercise for some bright military pilots.

27 posted on 03/15/2014 3:27:32 PM PDT by JohnBovenmyer (Obama been Liberal. Hope Change!)
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To: Procyon

I believe today the Malaysians stated that in fact the ACARs was turned off and, according the timing of it, that the person making the “All right, good night” radio call to KUL ATC was not the person doing it. As disabling the ACARs would be done in another part of the airplane that then indicates that someone was in the cockpit talking to ATC at roughly the same time someone else was manually turning it off elsewhere in the plane.

Ugh.....


28 posted on 03/15/2014 3:31:18 PM PDT by FAA
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To: Pearls Before Swine

My Verizon cell phone works reliably from cruising altitude, but my previous Sprint phone did not. (NB: non-passenger airplane!)


29 posted on 03/15/2014 3:32:54 PM PDT by theBuckwheat
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To: FAA

The whole thing adds to another dimension of fear. People would at least console themselves that a hijacking would mean a quick end.


30 posted on 03/15/2014 3:33:07 PM PDT by HiTech RedNeck (Embrace the Lion of Judah and He will roar for you and teach you to roar too. See my page.)
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To: Procyon

That is what was thinking also ... The only ping missing would be at landing gear down for touchdown. Doubt anyone could say for certain was disabled.


31 posted on 03/15/2014 3:33:20 PM PDT by no-to-illegals (Scrutinize our government and Secure the Blessing of Freedom and Justice)
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To: JohnBovenmyer

Since scheduled arrival in Beijing was 0630 and last ping was 0811 it is consistent with the aircraft carrying enough reserve fuel for a diversion airport plus 45 minutes for traffic holds.


32 posted on 03/15/2014 3:35:53 PM PDT by Procyon (Decentralize, degovernmentalize, deregulate, demonopolize, decredentialize, disentitle.)
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To: FAA

Malaysian misunderstanding of ACARS. There was no simultaneous turning off of ACARS while pilot is radioing goodbye. The last transmission of ACARS was just that: a text message then silence because ACARS wasn’t scheduled to send any more texts until the plane landed. No need for a second person to be climbing down into the electronics bay. One nan job.


33 posted on 03/15/2014 3:39:56 PM PDT by Procyon (Decentralize, degovernmentalize, deregulate, demonopolize, decredentialize, disentitle.)
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To: smokingfrog

Maybe not the transponder but that could be turned off by a breaker behind a panel in the cockpit. It would require expert knowledge but not difficult.


34 posted on 03/15/2014 3:42:56 PM PDT by BipolarBob
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To: theBuckwheat

Does it work over the ocean? I don’t think so... when you’re cruising at altitude over land, you are only 7 miles in the air. Add in a little horizontal distance, and you might still be no more than 10 or 12 miles from the tower. In the middle of the ocean... you’re hundreds of miles from any tower—you can’t connect.

If you don’t believe me, try to use a US cellphone on a cruise boat. It stops working an hour or two out of port (not counting using the outrageously expensive on-ship link).


35 posted on 03/15/2014 3:48:41 PM PDT by Pearls Before Swine
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To: Procyon
So we don't, at least yet, have to assume extra fuel and whatever that may imply. Still, as fuel load is an important boundary parameter and relatively easy to verify it should be pinned down. Fuel consumption would be affected by speed, altitude, etc. Knowing the initial load may still help narrow the search.

I presume the pings would end when the plane is powered down or when it is within a hanger, so we don't have to presume a crash ended them. Otherwise we'd have to presume the perps knew about and actively ended the pings, with whatever that implies, or accept a crash scenario.

36 posted on 03/15/2014 4:19:43 PM PDT by JohnBovenmyer (Obama been Liberal. Hope Change!)
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To: bigbob

There you go, a lot neater than the sloppily labeled fuse box in my house and somehow I manage to turn things off.

So, you can find that in a matter of minutes. Meanwhile we are “crowd sourcing” people to search satellite imagery in the Himalayas. Are they crowd sourcing people to search at the last radar location? Nope.

What if in addition to the things that were turned off the interior lights and navigation lights were also turned off. Let’s say that was confirmed by a fighter jet and when an attempt was made to make visual contact the airliner took some evasive action?

Sooner or later some government or group of governments was going to be faced with the decision to down a rogue airplane. The socioeconomic aftermath is incalculable. A coverup in in everyone’s interest and possibly this is why 10 countries are searching for a plane nobody wants to find.

It’s also a distinct possibility that governments that colluded in the decision are now flat denying any involvement (China & Vietnam).

At the last known radar contact the water depth is about 170 feet at most. Dangerous but doable even for a recreational diver. Remember, there’s no crowds sourcing of images there. Nine days to recover enough debris to befuddle any future investigate. This all serves the greater good.


37 posted on 03/15/2014 4:20:14 PM PDT by Fitzy_888 ("ownership society")
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To: nickcarraway

The ping was turned off over a larger body of water to make the search area huge, then my bet is the plane flew to Islamabad. Malaysian Airlines flies there anyway.
Islamists will load a nuke on it and fly it into Tel Aviv.
Obama obviously could care less about a stolen plane to be used on the Jews. He could, through his Muslim Brotherhood connections, even know about the plan already.
Would Israel shoot down a “lost” passenger jet flying in their direction?
At any rate, it will take a while to get the “bomber” ready.
It probably needs a new paint job.


38 posted on 03/15/2014 4:29:06 PM PDT by doc maverick
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To: nickcarraway

“The Wall Street Journal said the first loss of the jet’s transponder, which communicates the jet’s position, speed and call sign to air traffic control radar, would require disabling a circuit breaker above and behind an overhead panel.”

Absolute BS.

The transponder has a four position switch. OFF STBY ON ALT or Off Standby On and Altitude. You simply move the switch, located on the center console, to off or standby.


39 posted on 03/15/2014 4:30:44 PM PDT by CFIIIMEIATP737
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To: JohnBovenmyer
Getting to the final ping site, at least to the more interesting northern option (and who'd elaborately plan a slow suicide) means avoiding many radars. Either defenses there are much worse than presumed or the perps had the knowledge and skill to evade them. Determining what the perps could have known about those defenses and reverse engineering their possible routes may be enlightening. In the least it would be a good exercise for some bright military pilots.

Would that even have been necessary? I bet it wasn't the first civilian plane to end up in airspace where it wasn't supposed to be. My guess is that most military radar personnel just let these things slide on the assumption that somebody down the line forgot to file his paperwork ahead of time. Who wants the infamy associated with shooting down a civilian plane?

40 posted on 03/15/2014 4:43:58 PM PDT by Zhang Fei (Let us pray that peace be now restored to the world and that God will preserve it always.)
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To: nickcarraway

When I read the names of the two pilots, I knew immediately that the Religion of Peace already had control of that plane....


41 posted on 03/15/2014 4:53:11 PM PDT by Jumper
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To: Jumper

Records should show how much fuel was loaded on the plane.


42 posted on 03/15/2014 5:22:46 PM PDT by ncfool (Taking back America 2016.)
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To: Zhang Fei

The argument against the northern route is they couldn’t have reached it without being noticed. Absent some late announcement that Nepalese, etc. radar had seen them that argument fails IF they went north. It may be incompetence in which case someone’s superiors had better at least feign outrage. Or it may be their defenses, optimally run, aren’t as good as advertised, in which case someone’s taxpayers may be outraged. But if there are merely cracks in their systems, which MH370 exploited, there may be clues in how they learned such and there may be clues to their path and current position in discovering those cracks. It’s another angle on a problem for which we have little data. The US Air Force and Navy should contain folks able and willing to differentiate amongst those possibilities. If they don’t, even after 5 years of Obama, I’m outraged.


43 posted on 03/15/2014 5:28:12 PM PDT by JohnBovenmyer (Obama been Liberal. Hope Change!)
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To: Jumper

When I first saw a photo of the pilot (not the co-pilot), I knew he was guilty. A photo of the pilot, I read, is posted on facebook.


44 posted on 03/15/2014 5:33:03 PM PDT by Finalmente
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To: Finalmente

This part is true: flies the plane toward Mecca


45 posted on 03/15/2014 5:35:22 PM PDT by ncfool (Taking back America 2016.)
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To: Pearls Before Swine

“I think a bigger problem is that cellphones go out of range. Once they are off-shore, and 20 or 30 miles from a celltower, they do not work.”

That is all out the window. As it does not work that way. While on the plane cell phones communicate with the planes communication system. The plane then talks directly with a satellite which then communicates with the ground phone system. So in essence the plane itself is a cell tower. It is this system in the plane that sent all the final pings to the satellites. And it also explains the actual communication with cell phones that were still turned on when loved ones tried to call in.

It is possible that the cell phones were collected by terrorists. It is also possible that all normal passengers were already dead according to some theories.


46 posted on 03/15/2014 5:45:41 PM PDT by Revel
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To: dirtboy

See my last post. There is no such thing as being out of cellphone range.


47 posted on 03/15/2014 5:47:23 PM PDT by Revel
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To: nickcarraway

My suggestion: get the email address and cell number of every passenger. Then check for any outgoing messages .


48 posted on 03/15/2014 6:23:39 PM PDT by jimjohn (You don't get the kind of government you want, or the kind you need. You get the kind you deserve.)
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To: Pearls Before Swine

You are correct. Cell phone signals are high-UHF or near microwave and are almost pure line of sight. From 35,000 feet line of sight is over 100 miles, which is 15 minutes at 400 mph. At that distance the signal is far more limited by path loss than by line of sight issues. Consider that the cell phone transmit antenna is inside a metal tube and the only signal that escapes is via the windows. That loss factor would be quite a bit.

By saving that my Verizon cell phone works fine from cruising altitude, I was merely pointing out how wrong the 9-11 “truthers” are on this point and that it tells me all I need to know about their fanaticism.

I hold a FCC Commercial License and have the Radar Endorsement that was issued in 1969 apart from driving airplanes since then.


49 posted on 03/15/2014 6:33:14 PM PDT by theBuckwheat
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To: Revel
While on the plane cell phones communicate with the planes communication system.

That's true when everything is working normally. The cellphones power down to a minimum power mode, and the plane acts like a cell tower. I think it does this indirectly, rather than transmitting on the cell frequencies, but that's irrelevant here.

However, if the presumed hijackers were smart enough to power down the transponders, they were probably smart enough to turn off that system. If they did, the cell phones would still most likely work on their own when within a reasonable distance from the cell towers. A couple of hours out into the ocean, they wouldn't work. But, you are probably right that either the passengers were dead or the phones were collected. With the info we have so far, I'd vote for death by depressurization.

50 posted on 03/15/2014 7:03:50 PM PDT by Pearls Before Swine
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