What the hell would you do with an attack helicoptor? Strafe the Pentagon?
I suppose the Weapons Officer could shoot down the airliner with his 30mm chain gun. That's of course after the pilot deployed the super-secret turbo rockets that enabled the helicopter to catch up to the airliner...
Incidentally, that reminds me of another thing.
In their calculations the Loosers repeatedly remove the range of either Sidewinder or Sparrow AAMs for working out if the fighters were really "in range".
As I understand it, they don't shoot down errant airliners with missiles, theoretical or practical.
It's fine when every other aircraft in the area is either a friendly with IFF (Indicator: Friend-or-Foe) or an enemy (and even then you get friendly fire incidents). But this is a civilian airspace filled with civilian aircraft that don't have IFF at all.
They have to have visual confirmation, and they use cannon. Which means A) Getting in close to do a routine visual inspection of the aircraft at as close as a few hundred feet
B) Dropping back to gun range of no more than 2000ft (0.38 miles).
All this, of course, eats up precious time. The CTers imagine a Top Gun scene:
This is Whiskey 6, we have Tangos One, bearing three niner, angels 8. I have a lock, Fox One! Tango down!
-Andrew