This tutorial is not that hard to follow. Just follow the steps and you shouldn't have trouble. This is by Dmauro.
Here's what you have all been waiting for. The tutorial for making vehicles fly, in any level, multiplayer or singleplayer. Here's what you are going to do:
1-Explanation) Decide which vehicles you want to fly. If you want the WartHog or Scorpion to fly, you have to swap their physics with the Ghost's physics.
1-Offsets) For Bloodgulch
Warthog: 02340658 - 0234065C (Replace everything between these offsets with 407F8F80)
Scorpion: 023414D8 - 023414DC(Replace everything between these offsets with 407F8F80)
For other levels you will have to look up the raw offset of the Ghost's physics, and replace it with the raw offset for WartHog and Scorpion using that level's index as your offset guide.
2-Explanation) Now you have add some code to the vehicles' metadata which was stolen from the Banshee. To the left (I moved them to the bottom) there are two sets of code to splice in. One of them lets you hover without falling when you are not moving. The No Hover code is more like the Banshee because you actually fall if you are not moving or pressing backwards. Take your pick. This will replace some metadata for the vehicles you have chosen to make fly.
2-Offsets) For Bloodgulch
Ghost: 02885894 - 028858B8 (Replace everything between these offsets with one of the sets of code to the left)
WartHog: 0283465C - 02834680 (Replace everything between these offsets with one of the sets of code to the left)
Scorpion: 0286729C - 028672C0 (Replace everything between these offsets with one of the sets of code to the left)
For other levels
Ghost: (offset to metadata + 2F4) - (offset to metadata + 318) (Replace everything between these offsets with one of the sets of code to the left)
WartHog: (offset to metadata + 2F4) - (offset to metadata + 318) (Replace everything between these offsets with one of the sets of code to the left)
Scorpion: (offset to metadata + 2F4) - (offset to metadata + 318) (Replace everything between these offsets with one of the sets of code to the left)
As you can see, the data replaced it as 2F4 - 318. I believe this is where it is for other vehicles as well, so you should be able to apply these same offsets to get flying to work with other vehicles like a shade or a wraith.
(I didn't really pay attention to this bolded stuff so you don't need to either)
3) Now you can fly the vehicles. I did find a small side effect; if a vehicle gets flipped, it is much harder to get it flipped over the right way, but is possible if you just keep trying, or if you throw grenades at it. I haven't been able to try this hack out in all the levels, but I did get to play a four player game with all flying vehicles in Bloodgulch, and it is so much fun. There's nothing quite like an airborne tank-dogfight. Can't wait to try flying to the top of the Hang 'Em High building. Thanks for waiting, and enjoy!
Hover:
05 00 00 00 AE 47 61 3E 00 00 00 00 6F 12 03 3C
6F 12 83 3C F9 0F C9 3F 00 00 00 00 00 00 00 00
CD CC 4C 3E
No Hover:
05 00 00 00 AE 47 61 3E 8F C2 F5 3C 6F 12 03 3C
6F 12 83 3C F9 0F C9 3F 00 00 00 00 00 00 00 00
CD CC 4C 3E
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