How do I get the GOLD SKULL on THE STORM on Halo 3?

[Inky]

I look at videos, and I'm at the place, but it wont show up!!!
YES I I'M GOING TO THE SPOT WHERE IT'S SUPPOST TO BE AND IT'S NOT SHOWING UP!!! TELL ME EXACTLY!!!!

 

[Djking99]

wel u need to have normal dificuty or higher. u get a warthog u grenade jump on the cylinder. and u have to start from the beginning of the mission.