this actually is a good match because Human Torch flew from Africa (desert) to the US in little time. and flew cross country keeping pace with a commercial airliner, and for a time the Silver Surfer.
Ironman flew from Miami Florida to just outside Afganistan in a couple of hours .
Johhny also out ran a heatseeking missile indefinitely (for a bit much better then Ironman not being able to outrun it and had to use flares to misguide the missle) just needed a bit of time to shake it.
it wasn't a rpg! ... it was a ground to air heat seeking missile. Do they even have heat-seeking RPGs. Rocket Propelled Grenades don't have heat seeking ability as far as i know. Then again maybe you know more ;D