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Old 03-30-2014, 05:02 PM   #101
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Wow, I didn't realize this about the 777.
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Old 03-30-2014, 06:46 PM   #102
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I can't believe some of the banners that are put up on the news...
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Old 03-30-2014, 07:22 PM   #103
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Originally Posted by Roll_Bones View Post
That would be true to an extent if the car was made completely of metal and constructed in a way to allow electrons to move freely along the outside of the vehicle without penetrating the vehicle.
Most cars would fail this test miserably.
Faraday cages can do little if anything to protect from a direct lightning strike.

The only protection a car can provide from a direct lightning strike is the tires. They insulate the vehicle from the ground and do not allow the current to pass through the vehicle frame.
There is also a small degree of physical protection from the heat itself.
But make no mistake.
If lightning were to hit your car directly and you are inside the car, the chance of death is very high. The keyword is "direct strike".

I would rather be in a car during a lightning storm than being outside in it. But given the choice and knowing the magnitude of a lightning strike, I would prefer to be inside my house away from any windows.

If the car was a good Faraday cage, you would not be able to use your cell phone in it.
You are confusing what happens to a car when it's struck by lightning and the definition of "Faraday cage." In fact when a car is struck by lightning it becomes charged and like charge repels like charge. When the charge builds up high enough it doesn't matter if there are window holes. Your car becomes increasingly distasteful to the lightning and it finds other leakage paths to dissipate in.

I used to work in a Faraday cage when I was a 2-way radio technician. It's basically a copper wire box. Any radio transmissions hit the wire screen ad build up a field that repels the radio waves rather than allowing them through.

Your cellphone works in a car because of the holes where the windows are. They don't generate enough energy to charge up the car and repel the electromagnetic waves.

A lightning bolt is basically a huge electric flow, enough to charge up your car. A cellphone emits weak electromagnetic waves, not strong enough to do anything to prevent escaping from your car.

I'm a professional electronic engineer, or was until I got put out to pasture.
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Old 03-30-2014, 07:33 PM   #104
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Originally Posted by Roll_Bones View Post
Okay I will bite.

Terrorists hijacked the plane. They took control of the plane, decompressed the cabin and killed all the passengers, while they were relatively safe in the pilot bay.
Or they took the plane to 45,000' and allowed all to go to sleep (except them) forever.

They then took the plane to a terrorist country, hid it in a airplane hanger and at this very moment are retrofitting it with many pounds of explosives for a big show.

I am surprised someone hasn't blamed the President yet.
I too believe terrorists are more likely than not.

However, the altitude readings are so unreliable as to be useless. They came from "skin paints" (the raw radar returns absent transponder data). The truth is that there is no trustworthy means to determine the altitude of the aircraft after the transponder was switched off.

Additionally, there would be no need to climb if the pilot wanted to kill all the passengers. Commercial aircraft travel at about 33,000 feet, far too high for a human to survive depressurization. The oxygen masks are set to drop when the cabin pressure altitude falls below 10,000 feet. But some airports (few, but enough) are above 10,000 feet, so the pilot has a switch to disable the 10,000 foot trigger, to be used at landing at the few airports above 10K feet. (The cabin pressure is routinely adjusted to the altitude of the destination airport during the final phases of the flight.)

A pilot could easily kill all the passengers by throwing the switch that turns off the automatic deployment of oxygen masks at 10,000 feet, and then simply depressurized the cabin. At 33,000 feet most of the people would be unconscious in minute or so, and dead a few minutes after.

No need to climb to a high altitude to kill all the passengers. Easily done at normal cruising altitude by anybody who knows how to fly the aircraft.

BTW I'm a licensed private pilot since the '70s although I've never flown an aircraft with an oxygen system.
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Old 03-30-2014, 07:37 PM   #105
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Here's a few theories about the loss of contact with air traffic controllers:

1. It lost contact with the air traffic controllers because the equipment at the air controllers facility was old and faulty.

2. The air traffic controllers were busy posting selfies on Facebook

3. The controllers were drunk or stoned.

But the plane is still up there looking for some sober controllers who can land them safely---- in Roswell NM.
They lost contact with air traffic control because they flew out of radio range. That was what the "goodnight" was all about. It's a code word ("goodday" and "goodnight"") meaning that I am leaving the frequency and expect no further communications on this frequency. It is used during a hand-over to another ATC facility or when going out of communications area.

Nothing unusual here.
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Old 03-30-2014, 07:46 PM   #106
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If there was a fire, and they lost the electronics, the plane would have crashed right then. This plane cannot fly without power. A loss of the electrical/electronics would be the disaster in itself.
The plane supposedly flew on for several hours. If this is the case, there had to be a functional electronic system. Speculating on my part GB.

Like you, I have to go with the obvious. They are all dead and the plane resides on the bottom of the ocean. Hoping to find these poor souls is not going to happen (I wish I believed in miracles).
Modern aircraft are equipped with multiply redundant systems. For example, the 777 is a "fly by wire" system where the control wheel in the cockpit is not connected to the flight surfaces (ailerons, elevators, rudder) except by data links. The system is triple redundant at all levels, and only one level is necessary to continue control of the aircraft.

All important instruments are duplicated on both sides of the cockpit and are powered by separate systems.

Aw shoot, I hate to keep claiming expertise, but I worked for 4-5 years for RCA Avionics which was purchased and became Sperry Avionics. I designed electronic engine instrument systems.

The aircraft could fly with many of the systems gone, although a total oxygen fire in the cockpit would do a pretty good job of taking down the aircraft very quickly.
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Old 03-30-2014, 07:46 PM   #107
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I'm now leaning towards the terrorist theory. Also makes for a good movie plot.
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Old 03-30-2014, 07:55 PM   #108
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That theory came from a certified pilot. He said it is standard operating procedure to throw all the breakers when there is a fire so I must assume that the plane can fly that way and would not just crash. However the other part of his theory was that the pilots were quickly overcome by the fire/smoke/heat whatever, so that it flew for hours is kind of a wrench in that idea.
I'm a certified private pilot and I had a mid-air electrical fire enroute between Van Nuys (CA) and Lancaster Fox Municipal Airport, at about 5,000-6,000 feet. As the cockpit filled with smoke I was amazed to see my hand hit the master switch on the circuit breaker panel and turn off everything! I did it without any conscious effort. I didn't even know I could do that. At the same time I opened the little door in the pilot's window to let the smoky air out.

The aircraft was a Piper Cherokee 140. The engine system is totally separate from the rest of the electric system except for the electric starters. It runs on avgas (140 octane IIRC) and has dual magnetos that provide spark to the cylinders to keep them running when all the electrics are switched off.

Long story short, I lived. I turned off all the individual circuit breakers except the radios, turned the master back on and after a few minutes of sniffing, no smell, I contacted Fox and informed them I was inbound and may come in without radio contact. After landing I inspected what I could and found nothing wrong. I turned on everything (on the ground) and nada.

I flew back to Van Nuys and landed, reported the problem to the rental FBO. They said, "Yeah, somebody else had that last week on the same aircraft." I never flew with them again.

Getting back to large transport aircraft, I'm pretty sure you could turn off enough stuff from the cockpit to crash the aircraft, if pointing it at the ground isn't sufficient.



I can't see any scenario that is consistent with any of the passengers surviving. Perhaps crew in the cockpit...
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Old 03-30-2014, 08:01 PM   #109
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Originally Posted by Addie View Post
When we lived in Texas, we lived in a large trailer. One night there was a bad storm right overhead. A lightening strike hit the trailer. The next morning we went out to look. The whole side of the trailer starting at the top where the electrical was connected to the pole and all the way to the tires, was burnt and cut by the strike. Part of the tires were melted into the ground. I am still not sure what a Faraday Cage is, but I will assume we were in one that night. And I am forever grateful for those tires on that trailer.
Being surrounded by aluminum and insulated off the ground is what saved you.
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Old 03-30-2014, 08:04 PM   #110
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Okay to sum it up, my theories:

1. unexplained accident due to design of aircraft

2. intentional hijack by the pilot(s) or passenger(s) or both

2a. unsuccessful hijack resulted in a crash and destruction of the aircraft

3. successful highjack and rerouting to enemy airport to be used as a weapons delivery system at a later date. This is 2a above that succeeded.
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