I had that happen to me when I was 16 years old in a 68 1/2 ton. It had a new engine put in it, but apparently they did a poor job of rigging the the throttle setup, causing to stick at. In that model you cannot dig your toe under the gas pedal to pull up on it to free up the bind. The brakes did keep me from speeding out of control for a while then began to fade.
I ended up putting it in neutral and turned off the ignition. The engine did not like that at all. It backfired out of every orifice for quire a while with the ignition off. Must have had some serious hot spots on the cylinder head to keep the combustion going on all at the wrong time.
The worst part was when I was finally able to bring the truck to a complete stop, I was broadside in the middle of a busy highway and it was foggy out. I laid on the horn when I saw headlights coming, praying that they could see the broadside a truck in time to miss me.
I waited until I couldn't hear any traffic noise, jumped out and freed the stuck throttle linkage and started the truck and got off the road.
I'm thinking the operator of the Ford (You know, Fix It Again Tony) car did not have the sense of a 16 year old underachieving, habitual slacker to avoid a collision at full throttle without enough brakes.
