In light of the recent launches I was wondering why rockets launch straight up instead of taking of like a plane.
It seems to take so much fuel to go straight up, and in my mind I can’t see to get my head around why they don’t take off like a plane and go up gradually like that.
Edit – Spelling and grammar
Edit 2 – Thank you to everyone who responded. You have answered a life long question.
In: Physics
There are some good answers already on why rocket launches don’t go more horizontal than they do, but I think the thing that’s really missing is to point out that actually they don’t go straight up. Most rockets go at a slight tilt very quickly if not immediately and then gradually tilt over more and more as they get higher.
It looks like it’s going straight up in certain shots, especially if you’re zoomed in on the rocket, but this is largely because you don’t have a great frame of reference for what is actually up in that view. If you got a side-on view of the rocket as it took off that kept the launch pad in view the whole time you’d notice it was going sideways as well.
This graph isn’t very ELI5 friendly, so ignore it if you wish, but if you want an example, you can look at the [top left graph here](https://i.stack.imgur.com/hTuuH.jpg), which is showing the launch profile of a Falcon 9. In this graph it shows how far the rocket has travelled downrange (how far horizontally from the launch pad) vs how far it has travelled upwards (the different graphs are different launches).
As you can hopefully see it doesn’t really go straight up at all. If it did, we’d expect all of the lines to go upwards along the left edge of the graph for a while before moving over towards the right.
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