Ponies are small.
If you want proof of their genetic engineering origins, Equestrian ponies sizes are a good hint. The average pony is about four feet tall, which puts them in the size and weight categories of St. Bernards and similar dog breeds. Alicorns are coming up on five to six feet in height, but this is a rare thing. Which makes the fact that they’re sapient is odd, but their brains are built more…compactly than the evolution-driven brains that humans have. This leads to odd problems when their brains go wrong…but, usually a pony that has one of the various mental issues can be talked down and helped. Or, at the very least, the damage can be fixed.
Ponies are also pretty darned tough. Injuries and issues that would be fatal or crippling to a human merely results in long hospital stays, a Dope Slap, and strict instructions to Not Do That Again. Radiation, poison, baked bads…it’s a good thing that ponies have a proper vomit reflex and they heal very well, even before the advent of nanotechnology.
Why does this matter for discussing the Equestrian space program?
To steal a Bill Cosby line, “I told you that story so I can tell you this one.”
When the Equestrian space program began in 1009 ANM (and took off very quickly in 1018 ANM when the entire solar system changed), the most apt description of the program could be summed up as “very Kerbal with fewer, but more impressive, explosions.” One of the very Kerbal things that the Equestrian did was built was Orion Drive spaceships. Now, these were reasonably sized ships, usually launched into space from Equestria then supported by SSTO rockets or the steady development of space plane technology. When the Equestrians built the first orbital elevator, Orion Drive ships would be decommissioned and replaced by fusion torch drive ships, later ending with the development of gravity drive technology.
But, in that brief moment between the first Orion ship and orbital elevators, there was Sky Crasher. The ultimate proof that when ponies go nuts, they go nuts.
Sky Crasher was designed to be a massive cargo lifter, designed to heft truly epic cargoes to orbit and around the Equestrian system. To give you an idea of how massive the cargo lift they expected, the primer charge (used to start an Orion ship’s drive plate, because starting an Orion drive with a full power drive charge will ram the shock absorber pistons into the ship proper) in a standard Orion drive was rated at ten kilotons. Sky Crasher would have used a primer charge of three hundred kilotons. The full-powered drive charge was a six hundred kiloton two-staged propulsion charge.
(To give you an idea of how powerful this is, the W87 warhead on the Minuteman missile comes out at about 300-475 kilotons, and aren’t built for propulsion.)
Development work went as far as the building of the main drive plate before somebody in the Ministry of Space went “what sort of an insane idea is this?!?” and canceled the program. But, in that brief moment between authorization and cancelation, they expected to launch major payloads. The one completed drive plate would be sent to Canterlot and the entire Engineering campus of Canterlot University would be built around it. Engineering students would have to calculate the fluid dynamics of the water fountain cycling from the center of the plate.