Wow, this thread, along with a couple of others has really taken up a lot of my time this week.
I've resisted posting and adding to already stated theories and conjecture but I've been a bit irked by the common mention of the word "suicide". It is very, very uncommon for people who commit suicide to even contemplate hurting others, the 2 don't go hand in hand. Suicide attempt survivors often in fact report lucidity and clarity far greater than they've had for some time prior to and during the attempt, this makes some of the picture we now have difficult to reconcile. Murder/suicides (which if we're going to be technical is what we should be saying) are far rarer events and usually involve people known to the perpetrator, and normally again with what the perpetrator sees as "good reason" (jilted lover etc etc). Without evidence of the pilot/FO having a greivance against something (airline, chinese etc etc) it's really hard to reconcile this as an explanation. Consider that as many as a quarter of road deaths in regional areas are likely a result of suicide. These usually involve a single driver planting their car into a tree, not a bus full of random people.
Again, like any explanation of events, it is possible, but I think unlikely, and if we're going to refer to it then lets call it what is is and not simply "suicide".
Flyertalk has a list of possible airports within range of the last ping.
****The following runways of over 5,000ft are in the vicinity of the last ping:
Jalal-Abad Airport - Concrete runway of 5708ft.
Osh Airport - Runway of 8576ft with a surface of "ASP" (any ideas what that means?)
Andizhan Airport - Concrete runway of 9770ft
Kyzyl-Kiya Airport - Concrete runway of 5249ft
Fergana International Airport - ASP runway of 9383ft
Kerben Airport - ASB(?) runway of 5708ft
Namangan Airport - ASP, 10,698ft
Batken Airport - ASP, 5905ft
Isfara Airport - ASP, 9525ft
Talas Airport - Concrete, 5577ft
Lugovoy Airport - Concrete, 8204ft
Taraz Airport - ASP, 9514
Khudzhand Airport - ASP, 10,450ft
Isfana Airport - ASB, 5577ft
Chirchik Airport - Concrete, 8183ft
Tashkent East Airport - Concrete, 10,630ft
Tashkent International Airport - Concrete, 13,123ft
Shymkent Airport - Concrete, 9186ft
Chardara Airport - PEM(?), 5370ft
Pakhtakor Airport - ASP, 9845ft
Sugraly Airport - ASP, 6098ft
Pitnyak Airport - Concrete, 5576ft
Urgench Airport - ASP, 11,065ft
Nukus Airport - Concrete, 9175ft.
Yangadzha Airport -Concrete, 6600ft
Turkmenbashi Airport - Concrete, 8202ft
Kant Air Base - Concrete, 8859ft
Manas International Airport -Concrete, 13780ft
Naryn Airport - Concrete, 7037ft
Kashgar Airport - Concrete, 10,499ft.
This is assuming that there is about a 210km buffer on either side of the ping signal.
There are also a scattering of airports with runways between 2500 and 5000ft. I have no idea about any of these airports and which ones (if any) it would be possibly to sneak a 777 onto, but there's the list for anyone who knows more.****
Is it still possible after the Silk Air disaster for someone in the coughpit to switch off the flight data and voice recorders in flight?
I doubt it is suicide. Suicide is simply not this complicated.
Depends if you want to leave a legacy or life insurance payout for the wife and three kids....
It is still too complex for a suicide.
You can't switch them off, but there are always circuit breakers that may shut them down, or depending upon how they are wired, you may be able to get rid of one or the other by shutting down an AC bus.
... and France?
AFF Supporters can remove this and all advertisements
http://www.nytimes.com/2014/03/17/world/asia/malaysia-airlines-flight.html?hp
This article gives a good explanation of the estimated range from the last ping.
Also....
American investigators have been provided with much of the flight data obtained from radar and satellites, but they say they have far less information about what the Malaysian government has uncovered about the pilots and passengers or the Malaysian inquiry. Soon after the plane disappeared, F.B.I. agents and other American investigators “scrubbed” the names of the pilots and passengers — including two Iranian men who traveled on stolen passports — to determine whether they had any connection to terrorists and found none, according to the officials.
Officials in Washington say they are frustrated because they believe that the F.B.I. could be of substantial assistance.