Optimize Fuel / Time in planetary travel

[PaulG]

So, how do you optimize an interplanatary trip in terms of fuel and time?

So certainly, unlimited fuel gives you the quickest time, just fly direct.
Optimal fuel, could be the longest time.

So, how do you optimize the two together?

 

[Urwumpe]

You can use accelerated transfers, which place the apogee slightly outside the target planet. These can be a good compromise between travel time and fuel consumption.

 

[RisingFury]

Ion engine would sure come in handy...

 

[HiPotOk1978]

One thing to remember when you are going anywhere in space...
Once you put energy into your course, your gonna have to get rid of it somehow once you get to where your going. Depending on where your going determines your options.

Aerobraking is an awesome way to decelerate if you have an atmosphere. turn your velocity into heat with friction. If you are going to say the Moon, your options are pretty much limited to firing engines in retro and burning fuel. Good news is of course is your weight is lower cause you burnt some of your fuel to get there so the mass of your craft is lighter. If you not planing on staying in the area and your craft is unmanned, and just want to fly by and to with the craft after that, braking or limited braking is only going to be needed

 

[Eagle]

The 'Optimal' path depends on how much you value your fuel with respect to time. If you only care about fuel, you'll take Holtzman transfers. If you only care about time, it is a continuous burn.

Really, its a judgment, you can make up some formula that you value 1000kg of fuel as equal to one day in time. And you can find out a path that will get you from place to place with that ratio.

But, the easy way is to say you feel like is to pick a transfer and load up on fuel.

 

[agentgonzo]

The 'Optimal' path depends on how much you value your fuel with respect to time. If you only care about fuel, you'll take Holtzman transfers.

Hohmann Transfer

Minimising fuel could also make use of the Interplanetary Transport Network