Halo - Combat Evolved Easter Egg - Skip 30 Minutes of Assault on the Controll Room

Start the level assault on the control room on any difficlty and find yourself a sniper rifle and an rpg.
Theres a sniper at the bottem of the first bridge by the warthog i think.
When you get to the part where you fight the second load of hunters go find the dead marine bodies to the left and get a rocket and continue up through the cave up the path and stop when you get to the flat.
You should be at the top of the path in the area with the 2 bridges.
Walk straight ahead up to the tree and jump onto the rock beside it (kill everyone first but don't go any farther than the rock cos there's a trigger once you pass it the elite will hop into the banshee and fly off).
You should be on the rock now, jump up with the sniper rifle and look ahead in the zoom find the banshee and have it in your sights now switch to the rpg and shoot once you've jumped then have a look to see if the banshee has been blown over if it has continue walking down to it if not try shoot it again it has to be upside down to do this glitch (because on this game the elites can't flip vehicles).
Go up to the banshee, kill the elite, flip the banshee and fly onto the bridge. I'm not sure whch one is the right one but just have a look around
and since you skip a few checkpoints doing this there will be no more enemies so it's much faster to finish the level and it skips about 30 minutes of it as well.
Hope you liked this glitch/egg/thing.