Only in the sense that we dont have a clue what happened due to lack of wreckage. What kicked off the AF447 ccrash was incredibly turbulent storms. It was calm as anything the other night. Weather will not be the issue,
No...well, incredibly unlikely.
Forstly, the idea that a 777 could land anywhere without anyone noticing is just incredibly unlikely...but maybe they were hijacked then crashed miles away? still unlikely...
There's been a lot said about the transponders, ill try explain a few things that might clear this up for some.
Yes, transponders can be turned off, ive had plenty of planes under my control get airborne and the pilots have forgot to turn their transponder on. It literally has an on/off switch.
However, most RADAR have two systems...or more accurately two types of RADAR. These are Primary and Secondary RADAR.
Primary RADAR is literally raw RADAR, the RADAR dish emits a beam, it bounces off something (anything) metal (doesn't always have to be metal!) and the computer puts a 'blip' on the RADAR screen where the beam hit. You cant (unless you have a stealth plane) turn that off.
Secondary RADAR is connected to this system but it emits a signal, and then the transponder on a plane hears this signal, and then it replies with a four digit code that ATC give it, lets say its '1234' and other information like altitude/heading/speed This is how ATC know how high and fast planes are going.
The RADAR dish then hears the reply of '1234', it knows that it came from the same place as the other 'big metal thing in the sky' return it got from the primary RADAR and then it tells the computer that this 'blip' is plane '1234' the computer then knows that the plane with code 1234 is...lets say Easy123 and on the RADAR screen it shows the original 'blip' and a label with 'EASY123' next to it with all the data (altitude/speed/heading etc).
So, although the transponder can be turned off or fail, the primary RADAR aspect cannot. The ATC RADAR will see the information (name/altitude/speed) disappear but the 'blip' will still be there, so although they wont know how high it is they will know the area it is.
Now, assuming the RADAR system uses both primary and secondary (i'd be very surprised if it only had secondary...although there are some that do), if the two signals just disappeared, there s only one of two answers, well...one answer...it exploded in mid air. Whether thats by a bomb or catastrophic structural failure, we wont know unless we find wreckage....which if it blew up at 35000 ft, it could be spread over a MASSIVE area.
Not necessarily. Pilots are trained to employ 'Aviate, Navigate, Communicate'. Basically this means in an emergency situation, you sort our whats going on and fly the bloody plane before talking to ATC. If its a catastrophic structural failure or explosion, its likely they wouldn't have had time or will to talk to ATC...after all, what could we do in that situation? So, it may not be THAT unusual.
Hppened before (egypt air i think) but again, why turn off the transponder? Also, see previous point about Primary/Secondary RADAR
They will have an Emergency Locator Beacon (ELT) that will auto turn on when crash happens, it may have been destroyed, and its range isnt that far (bout 5 miles i think). The Cockpit Voice Recorder and Flight Data Recorder (Black Boxes) have locator beacons as well but they are even weaker and they wont get it from the air, they will have to be searching in a boat right over it.
Well, if you take the AFR447 crash as an example, they just glided down after stalling (well, gliding might be a bit misleading). Ive always thought it very likely everyone on board wouldn't have had a clue what was going on until the end...after all the pilots didnt, they only noticed and started to power up with seconds to go.
If its an explosion in mid air then you would lose pressurisation, and at 35000 ft you would go unconscious very quickly, and in fact its (apparently) quite a nice way to die as its really quite euphoric apparently!