[George Hopp]

I would say that chance of the pilot being able to do anything to clear jams in his fuselage-mounted MG 151 was zero to none.

If you look at the weapon installation, you will see that that rear of the gun is ahead of the control stick. So, to gain access to the weapon, the pilot would need to release his seat belt, bend way down under the instrument panel, remove the protective cover (if it was fitted -- and where to put that). Then somehow reach forward to clear any jam. And, if you have seen a 109 cockpit, it is very small, so the pilot would be trying to do this without touching the control stick or the rudder pedals, or any other flight controls. Meanwhile, since his head is under the instrument panel, who is flying the aircraft?

After all that babbling, I suddenly remembered that the Mauser gun could only be loaded and cocked electrically. So, trying to manipulate it manually to slide back the bolt to free a cartridge would not work.