Is it that easy to penetrate a Boeing cockpit? Don't they have security doors and such? I reckon that hijackers can enter it over time by pressuring the flight crew, but wouldn't the pilots become aware of the hassle before they come in?
Obviously we don't know what actually happened on the flights, but we can speculate.
FAA regulations stipulated that cockpit doors had to remain locked during flight, however this wasn't strictly adhered to by all airlines. We do know that all of the flight attendants on AA11 had keys to the cockpit, and a similar situation was probably in place on the other flights.
We know that the Al Qaeda hijackers were specifically trained on this part of the operation. Their training stipulated that the priority was to seize the cockpit - controlling passengers was of secondary importance. You will notice that in all the flights they had people right up the front nearest the cockpit door.
From there they could monitor movement in and out of the cockpit and, for example, strike when a flight attendant was in the doorway (so it was open).
So they did keep track of all planes except flight 77?
Yup.
There wa indeed a lot of confusion. I just want to know whether this confusion is due to human err, or is it really all the protocol incompatibilities with the situation..
The hijackers intentionally created confusion. It was a big element of the operation.
Other factors caused problems to.
When a major air disaster happens, most airlines have a standard response protocol where they go into lock down. While the crisis is unfolding they stop any information being released about the flight affected, to protect the privacy of the passengers, crew, and their families.
On 9/11 this was a problem, because it meant American Airlines didn't confirm the loss of AA11 until nearly 2 hours after it crashed (airlines track their aircraft independent of the FAA). This allowed, for example, the false report that AA11 was still in the air and headed for Washington DC.
There wasn't a huge amount of confusion however. The big problem was there was no confirmed hijacking. Obviously you don't want to start making drastic moves and cause utter chaos, as well as delaying literally millions of passengers without good reason.
The controllers spent some time in each case trying to contact the flights, before deciding they were hijackings. This is why there was a delay in the military being notified of the threat.
The main problem was time, really. The attacks happened quickly, tightly timed together, and there simply wasn't sufficient time for the FAA and NORAD to respond to the threat. They were in "peace mode". In order to respond to something like 9/11 they really needed to be at an elevated threat level.
If you take the fighters, for example, it's not like jumping in a car, turning on the ignition, and just pulling out onto the road. It takes time to go through all the pre-flight checks, power up, get the engines up to temperature, taxi out to the runway, take off, climb to altitude, and head to the target area.
On 9/11, NORAD allowed 15 minutes for this to occur.
Now, let's look at a breakdown of the flights:
AA11
0759 - AA11 Departs Logan International
+14mins - AA11 Hijacked
+21mins - AA11 turns off IFF beacon and deviates from flightpath
+25mins - AA11 turns for New York - now clear it has been hijacked
+38mins - Boston ARTCC notifies NEADS of hijack
+39mins - Otis fighters put on battle stations
+45mins - Otis fighters launched despite no clear coordinate to AA11
+47mins - AA11 hits WTC1
+53mins - Otis fighters in the air
UA175
0814 - UA175 departs Logan International
+30mins - UA175 Hijacked
+38mins - UA175 turns off course - now clear it has been hijacked
+49mins - New York ARTCC notifies NEADS of hijack
+49mins - UA175 hits WTC2 (Otis fighters are approx 120miles away)
AA77
0820 - AA77 departs Washington Dulles International
+34mins - AA77 hijacked, transponder turns off. Vanishes from Indianapolis radar and assumed crashed
+36mins - FAA notified that AA77 may be hijacked
+74mins - NEADS find out by chance that AA77 is also suspected hijacked, current location unknown
+75mins - AA77 is detected on radar headed for White House
+76mins - Langley fighters (already in air) are directed to Washington DC
+77mins - AA77 hits The Pentagon. The Langley fighters are approx 150 miles away
UA93
0842 - UA93 departs Newark International
+46mins - UA93 Hijacked
+57mins - Now clear that UA93 has been hijacked
+81mins - UA93 crashes
+85mins - NEADS told UA93 is hijacked
+100mins - NEADS told UA93 has crashed
-Gumboot