Why are space rockets shot straight up? Wouldn’t it be easier to make a spacecraft that ascends like regular aircraft until it’s out of the atmosphere?
In: Technology
The main problems with rockets is that you want them to go fast not necessarily up.
The international space station for examples where a lot of rockets and spacecraft travel to is only 400 km (250 miles) above the ground.
400 km is a distance you could travel in a car in about 3 hours depending on local speed limits and traffic. It is really not far away at all. A supersonic rocket can travel that far in a couple of minutes.
The problem is not really getting to the place where the ISS is, but matching its speed.
The ISS is orbiting at a speed of 7,66 km/s or more than 22 times what would be the speed of sound down here.
The main purpose of a rocket is not to get that high up, but to speed up enough to match that speed.
The obvious issue is that if you tried to go that fast anywhere near the ground, you would have to content with extreme amounts of air resistance that would try to slow you down and heat up your craft in the process.
So rockets first go up until they reach an altitude where there is less air to get in their way and then they start doing their real work of speeding up sideways.
In order to save fuel you want to get to a place where there is less air in the way as soon as possible and that means going in a generally upward direction at first before curving to go into a more horizontal direction.
If you tried to make a spacecraft that started out like a plane you would end up wasting all sorts of fuel to gain latitude.
This does not mean that it is not a thing that has never been done.
In fact Richard’s Benson’s Virgin Orbit launched a rocket from a Boeing 747 this year.
They used the Boeing to fly up with a rocket suspended under its wing and then when they reach sufficient released the rocket to fly its own way. In practice this is using the large jet plane as a reusable first stage for the rocket.
This works to a degree, but there are obviously limits to how big a rocket you can put under a 747’s wing. It is a big plane, but not big enough to carry a rocket big enough to carry humans into orbit.
Many other ideas have been suggested in the past as theoretically possible like building a jet engine that you can turn into a rocket engine once the air gets thin enough. It is one of those things that sounds doable in theory but less so in practice.
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