[snopercod]

The re-entry heat is dependent not only upon the speed, but on the mass. What's the formula for kinetic energy? (Grabbing my Marks' STANDARD HANDBOOK off the shelf in front of me) Oh, there it is: E= ½mv²

Since SS-1 is very light, that helps.

OTOH, the resins used to build fiberglass airplanes start to weaken at about 200° F.

An aircraft parked on the ramp at PHX gets hotter than that.

I really don't know how they do it (the secret of which may be the big story here.)

Here at the house, I have Burt Rutan's set of three video tapes on basic composite construction. I think they are circa 1980 or so, so they may be collectors items now.

[Robert A Cook PE]

Right: you're looking at total kinetic energy there (1/2mv^2), which has its source the total of potential energy + kinetic energy at apogee.

For this particular flight series, kinetic energy at apogee is very, very low. Thus, total energy that has to be "burned off" by (1st) air resistance through supersonic "weather-cocking" of the tial surfaces, (2nd) by "regular" supersonic flight air resistance down to landing, and by (3rd - and last) heat is almost exclusively determined by maximum height.

Additionally, some is burned off by friction of the fwd skid plate at landing, regular wheel brakes, and coasting down in the sub-sonic glide path.

This isn't a "normal" glued together Rutan airplane: 200 degrees isn't the skin breakdown temperature.