Quote:
Originally Posted by freebeard
A caliper held to the screen suggests ~50% greater diameter at the aft end. One wonders if it makes a difference on the way up.
Also the effect of four supersonic shock waves from the four protruding landing legs.
|
Under rocket thrust, the expanding gases act as a virtual structural boat-tail. The drag will vary from subsonic- to- transonic-to- supersonic.
A larger rear cross-section is like arrow feathers.
On all launches, you'll here cap-com announce ' max-Q', where the airframe is experiencing the highest aerodynamic loading of the flight.
If the 'tube' isn't crushed by then, between payload and thrust, or deformed by aeroelasticity, the engineers have made a successful design.
And as P. has mentioned, if intermittent thrusting, never allows the tube to exceed its aerodynamic heating threshold velocity, it won't need tiling.