Hi all,

 

 

I'm having a difficult time trying to answer what I think is a simple question. When a spaceship goes near a planet, can it takeadvantage of both the gravity assist AND oberth effect, or can it only pickone?

 

 

From a gravity assist, the spaceship could pick up as muchas Vf = 2U + v for an increase in speed

 

From the Oberth effect, it can pick up as much Vf = sqrt((Δv+ sqrt(V^2 + Vesc^2))^2 - Vesc^2).

 

 

(Δv is burn, Vesc isescape velocity at planet peri, V is initial velocity, U is planet's orbitalspeed, Vf is the ship's final velocity after leaving the planet due to eithereffect)

 

 

How do I calculate, roughly, the final velocity fromcombining both effects? I think it should be simple, but I'm not seeing it. Its tough to find on the web.

 

The simple answer, YES!

The simple answer, YES!

It wasn't a yes or no question. It was A or B — can it do both, or does it have to pick one?

http://en.wikipedia....ered_slingshots - So yes you can benefit from both. No clue yet as to find out a method for combining the effects.

It wasn't a yes or no question. It was A or B — can it do both, or does it have to pick one?

I thought you asked the question could you do both, and I answered YES!

The math is very simple, you're interested in the velocity squared over 2, which is conserved except when you fire the rocket engine,

or it is changed by gravity.

Edited October 2, 201213 yr by Ronald Hyde