SSTO Question

[Mudkip909]

I was wondering if i could do a SSTO to laythe while refueling in the middle of the mission. like, i would have a tanker ship orbiting dres.

[Lelitu]

Refuelling an SSTO in flight is very commonly done, as that's the easiest way to extend any vessel's available deltav.

That said, Dres or Duna are not the places you'd put the tanker for a mission to Laythe. It would make the trip a lot slower and cost more fuel than a direct flight. For maximum benefit you want to refuel in low kerbin orbit, and again in Laythe orbit. 
Getting to orbit from kerbin/laythe is literally half the delta v of the one way trip.

[Spricigo]

well, SSTO means Single Stage To Orbit. If  you reached orbit without dropping parts you may refuel or go to laythe and your craft will still be a SSTO.

BTW If you want ot go from kerbin to Jool, Dres is a terrible place for refuelling station. Going to Jool is actually cheaper than going to Dres because you can capture around Jool without expending fuel.

[Van Disaster]

I would put the tanker in Kerbin orbit, it takes about 2k dv to Jool from LKO iirc and you can aerobrake to slow down ( use several passes of Laythe, Jool itself would not be a good idea unless you've turned heat off! ). If you want to come back again, then somewhere in the Jool system is the other place to refuel. The only reason to go somewhere else on the way - assuming it's not a mission goal - would be for gravity assist, and that is not a great time to be refuelling; your tanker would have to match your trajectory, and that trajectory would be sending it to Jool anyway. Space missions mostly don't continuously burn fuel, usually at the beginnings & ends, so those are the spots you want to consider adding more fuel - there's not generally an advantage to doing anything in the middle.

That was assuming SSTO spaceplane with airbreathing engines anyway - you might have to refuel before landing on Laythe rather than after if you're pure wingless rocket SSTO ( or ISRU *on* Laythe ).

Edited July 30, 2017 by Van Disaster

[Mudkip909]

oh ok

[Vanamonde]

Remember that travelling in space is very counter-intuitive for ground-living-creatures like us. If you stop at Dres on the way to Jool, you will have to burn fuel to slow yourself to orbit Dres, burn more fuel to arrange a rendezvous, and then burn more fuel to get back up to speed to transit to Jool. You'll end up burning much more fuel that way than if you went straight from Kerbin to Jool. 

[Mudkip909]

what about a fuel tanker in the middle of nowhere lol

btw im a bottle rocketeer

[Vanamonde]

Nothing just sits in the middle of nowhere in a solar system. It's going to be subject to gravity, and that means it's got to be orbiting something, and that means it's moving. And that means you'd have to match course and speed with it to dock and transfer fuel. Which would mean burning a lot of fuel, unless it's already on close to the same course you want your main ship to be taking. In which case that means the tanker is already heading to Jool, or close to it. In which case you might as well just put your payload on the tanker and not bother sending a second ship.   

The way to travel between planets is to reach the right velocity, so once you've achieved that, stopping anywhere short of the destination is a waste. Refueling only makes sense if you can do it at or near the origin planet or the destination planet. 

[Mudkip909]

k

MATT LOWNE DID A 500 SEAT SSTO TO LAYTHE!?

[Bottle Rocketeer 500]

I agree, just mind-blowing work.

[Wanderfound]

Alternately:

1) Launch an SSTO to LKO. Build that SSTO with a docking port inline with the centre of thrust. Refuel it in LKO.

2) Launch a drop tank assembly. Dock it to the SSTO.

3) Use the fuel in the drop tanks to get to Laythe, discarding them as they empty.

4) Arrive at Laythe fully fuelled.

 

Like so:

 

Edited July 31, 2017 by Wanderfound

[Red Iron Crown]

You can do SSTO to Laythe and back without refueling.

 

[Mudkip909]

noice, download? just askin'

[Red Iron Crown]

2 hours ago, Mudkip909 said:

noice, download? just askin'

https://www.dropbox.com/s/owde581dj1o4pcv/SSTLR4.craft?dl=0

This was made in 1.0.4, so some things may have changed a bit. It's also pretty difficult to get to orbit in the first place as it struggles to break the sound barrier.

[qzgy]

The easiest way to do it is to have your SSTO, with isru preferably, launch and go to minmus to refuel. Needs about 5000 m/s of delta-v for a nice safe margin. Then go to jool. Via gravity assists or whatever, doesn't matter. Tylo capture, and adjust to get into laythe orbit. Much nicer here, cause if you use LF only on Nukes, you have a lot ore delta-v cause of the Higher ISP. Then land, isru rufuel, and do whatever you need to. Then launch and try to use tylo to get out of Jool SOI. Or burn. Harder to burn though. Fall back to kerbin. You can do some gravity assist wizardry o reduce your speed at kerbin, but you should end up near kerbin. Burn, or aerocapture, and land.

Minmus is near the edge of kerbin SOI. It also doesn't take too much delta-v to land and takeoff, so its not a total kill on delta-v.

Its also quite nice to gravity assist with tylo into joolian orbit. Much nicer than giant burns.

 

This is the best option of something with isru. If you want to use fuel depots, I would say to put one in Minmus orbit and another in Laythe orbit.

[Wanderfound]

What's the total ΔV requirement for a Laythe return?

Craft file at https://www.dropbox.com/s/mkniu3tnpnzd9qc/Kerbodyne Pathfinder.craft?dl=0

[Urses]

In one previois playthrough i tried a asteroid train system. Catch an asteroid build a refining station on it and bring it on a inclined orbit around sun with a 3 year period. This way i get a catapult station for outer space with a startimg window from Kerbin all 3 years. The orbit was planned for near path-by's on Kerbin and i could start and recover my missions on this point.