Spoke to the Ginger Beer on my last departure. Wheel plugs melt at a set temp in order to deflate the tyres and avoid them exploding due to the expanding, hot air inside. Clever. Stops damage and death after a high energy stop. Thanks for the responses to the dudes who did.
Regarding the design compromise, the 76 wing was moved forward as a compromise to the aft loaded CP and thus partly negate the effect of the pitching moment. The 75, I am not sure, but that is the case with the 76.
Ye of little faith, a web search will help you here, but I'd rather see Boeing on the title of the webpage, hence my call for a validation.
Unfortunately, Boeing say next to nothing about their aircraft.
Oh yeah (needing the edit here), careful, as the limiting mach number is not the critical mach number.
Mcrit is as you have described, but the limiting mach is that speed at which compressibility effects begin to affect the controllability of the aircraft, ie, high speed buffet and so on.