This achievement is easiest to unlock on the level "Corridor of Power" in the Queen's Corridor, England. First fire into the corridor and get a Smashbreaker. I'd suggest not shooting too far down the corridor as you have to come back to where you started fairly quickly. Once you have a Smashbreaker, come back to the balcony behind where you started and head to the far wall to either the left or right. There will be a small warp at the base of the wall. Go into it. You will come out the other warp and be going in a direct line to the hole. Do not turn left or right at ALL and the second you hit the flag, hit LT and RT at the same time to airstrike into the hole. This will also get you the Retee achievement and 1st Warp achievements if you don't already have them.