How quickly would humanity rebuild its scientific and technological knowledge base, if all the accumulated knowledge and technology was wiped out, except for the knowledge that they once possessed it?

For example, you lose all the nitty gritty knowledge about the theory of electromagnetism and atomic theory, and how to make electricity and electric light, but you still know that electricity, nuclear power plants, and electric lights once existed.
You lose the knowledge and the science behind aerodynamics and powered flight, but you still know that you were once capable of doing it.

It took thousands of years for the human species to get from banging rocks together, to flying a helicopter on Mars.
How long would it take, if they already knew basic picture of what is possible, and you remove the retarding element of “humanity will never X” and “X is impossible”?