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Go to space with a thud!

Foxster

By Foxster
in KSP1 Challenges & Mission ideas

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Foxster

Foxster

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Inspired by this thread http://forum.kerbalspaceprogram.com/threads/135495-Thuds-Are-Beautiful about how great the often unloved Thud engine is, I give you...

The Go To Space With A Thud Challenge!

Its pretty simple: How far can you go after launching from the KSC powered only by one Thud engine?

Here's my craft making Kerbin orbit:

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Furthest from the KSC wins. Can you escape the SOI? Make it to the Mun? Beyond?

You can fix your engine radially (might need to adjust the angle a bit), on the bottom of the rocket, at the top, wherever. You can stage the craft or not. You can even refuel it (as long as you take an ISRU+drill on board into space).

Simple rules:

  1. Stock only
  2. No cheaty stuff
  3. One craft and one launch
  4. Manned or unmanned

Scoreboard (In no particular orbit)

mattssheep4 -- To the sun's orbit within Eve's orbit

Robet.G -- Leaving Kerbin's SOI

MoeslyArmlis -- 1.2Mm Ap orbit

Slashy -- 70K orbit + spare dV

xendelaar - Munar orbit

littlebuddy0 - 2,735,600m Kerbin orbit

Edited by Foxster
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Robet.G

Robet.G

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Could you upload the .craft file somewhere? I'd love to try launching this with a gravity turn so as to eject Kerbin prograde and see how far it'd go :)

It is ejected Kerbin prograde, it generates an AP of 18 million km.

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Superfluous J

Superfluous J

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It is ejected Kerbin prograde, it generates an AP of 18 million km.

But not with a gravity turn. You fought 1G (well a little less as you went up, but not significantly) of downward acceleration throughout your entire burn. If you'd done a gravity turn, you'd have gotten (possibly much) farther.

Back in .90 with FAR we did some tests and even a high-TWR ship can see a 10% benefit (10% of the fuel's left when you get as far) by doing a gravity turn. Low-TWR craft could see anywhere from that to infinity (not really, but there is no bounds as TWR goes to 1.0)

Also in picture 6 it doesn't look perfectly prograde. It looks like you're 10-30 degrees past sunrise.

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ment18

ment18

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I'm confused about this rule:

How far can you go after launching from the KSC powered only by one Thud engine?

Does this mean I can launch with a thud, go suborbital then switch to something else,

Launch from pad with thud then use something else (thud t/w>1),

Fall from launch clamps with a thud on then switch to something else, or

Use only a thud for the entire flight?

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Foxster

Foxster

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I'm confused about this rule:

How far can you go after launching from the KSC powered only by one Thud engine?

Does this mean I can launch with a thud, go suborbital then switch to something else,

Launch from pad with thud then use something else (thud t/w>1),

Fall from launch clamps with a thud on then switch to something else, or

Use only a thud for the entire flight?

The last one.

The idea is that you have a single craft launched from the KSC. It's only propulsion is then and remains a single onboard Thud engine.

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narf0708

narf0708

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I'm confused about this rule:

How far can you go after launching from the KSC powered only by one Thud engine?

Does this mean I can launch with a thud, go suborbital then switch to something else,

Launch from pad with thud then use something else (thud t/w>1),

Fall from launch clamps with a thud on then switch to something else, or

Use only a thud for the entire flight?

The last one.

The idea is that you have a single craft launched from the KSC. It's only propulsion is then and remains a single onboard Thud engine.

What if one makes a refueling station attached to the thud-rocket(so that it is contained in a single craft file and is 'launched' from the VAB only once) with a decoupler, launches the thud-rocket into LKO carrying a payload of a fuel tank(empty) with docking port, drains all extra fuel into the tank, undocks, returns and lands at the refueling station that was left on the KSC's launchpad to refuel, then returns to orbit, redocks with the payload in LKO, deposits more fuel into it, and so on and so forth.

Of course, one would need to be very efficient at orbital rendezvous(with only one thud, and no RCS, I'm assuming) and also pretty good at landing at a very specific location. I know that I don't have the piloting skills necessary for this, but it should be possible for someone who is more capable than I am to get a rather large amount of fuel into orbit, and from there, to just about anywhere.

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Superfluous J

Superfluous J

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What if one makes a refueling station attached to the thud-rocket(so that it is contained in a single craft file and is 'launched' from the VAB only once) with a decoupler, launches the thud-rocket into LKO carrying a payload of a fuel tank(empty) with docking port, drains all extra fuel into the tank, undocks, returns and lands at the refueling station that was left on the KSC's launchpad to refuel, then returns to orbit, redocks with the payload in LKO, deposits more fuel into it, and so on and so forth.

Of course, one would need to be very efficient at orbital rendezvous(with only one thud, and no RCS, I'm assuming) and also pretty good at landing at a very specific location. I know that I don't have the piloting skills necessary for this, but it should be possible for someone who is more capable than I am to get a rather large amount of fuel into orbit, and from there, to just about anywhere.

I believe this would not only fit the requirements of the contest but would also be awesome. Also, way too much work considering I suspect the ship posted that can escape Kerbin's SOI can possibly also reach Sun escape velocity if it follows a gravity turn.

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Foxster

Foxster

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What if one makes a refueling station attached to the thud-rocket(so that it is contained in a single craft file and is 'launched' from the VAB only once) with a decoupler, launches the thud-rocket into LKO carrying a payload of a fuel tank(empty) with docking port, drains all extra fuel into the tank, undocks, returns and lands at the refueling station that was left on the KSC's launchpad to refuel, then returns to orbit, redocks with the payload in LKO, deposits more fuel into it, and so on and so forth.

Of course, one would need to be very efficient at orbital rendezvous(with only one thud, and no RCS, I'm assuming) and also pretty good at landing at a very specific location. I know that I don't have the piloting skills necessary for this, but it should be possible for someone who is more capable than I am to get a rather large amount of fuel into orbit, and from there, to just about anywhere.

Dude, if you can be bothered to do all that then you will receive a total of 17 Brownie Points and a special place in this challenge's Hall of Fame.
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The_Rocketeer

The_Rocketeer

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After many failed attempts at making a space plane using a single Thud, I decided to try rocketry.

This is doable, I did a quick test just now and very nearly made orbit on the first go (about 200m/s short, but I could comfortably have brought more fuel).

  • Use a single 1.25m fuselage (i.e. stack) with a Mk 1-2 Cockpit behind a fairing.
  • Aim a little over 1440 LF (plus Ox of course). I used 1440 and didn't quite get there.
  • Use only Wing Strakes for wings - my craft had 4x2 of them, plus 2 Type C Wing Connectors and a few control surfaces, but I think the Type Cs were dispensable.
  • The LF+O tanks will drain front-to-back, so shut off all except the middle one, and manually transfer fuel (by right clicking all tanks and using the 'in' button) to replenish it from all tanks evenly.
  • Lock gimbal on the Thud until your circularising burn at apoapsis, then unlock it. Don't bring reaction wheels or batteries, you don't need the weight.
  • ASCENT PROFILE: Get off the runway ASAP and pitch up as much as possible while still accelerating, until u get to ~45 degrees pitch. Hold that attitude until your apoapsis is about 60km and switch to track prograde. Shut off and coast when your apoapsis gets to 72km. Circularise at apoapsis (don't forget the gimbal here).

and lastly, remember me in your glory on achieving the first Thud spaceplane to orbit. Nighty night!

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Moesly_Armlis

Moesly_Armlis

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Well after taking your advice on those shock cones and a little tweaking and weight reduction the new SpaceThud the Third can now leave Kerbin SOI.

wUiFEZp.png

There was over 900 m/s delta-V left over after reaching orbit and burning that fuel resulted in an apoapsis of 74 Mm.

VAnxUCR.png

hdGOVsx.png

@ The_Rocketeer I thought there was a solution to the space plane problem and pursued it for about a week. After reading your suggestions I might go back to the design.

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Foxster

Foxster

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Nice one.

Of course, you could get a little cheaty and rotate the shockcones through 180°. That will reduce their drag and also the drag at the back of the tanks/engine below.

Oh and with a gravity assist flyby of the Mun I think you'll make it to an orbit of the sun - maybe.

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xendelaar

xendelaar

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Here's my entry: Thud Castle

It looks like most entry's on this thread (unintentionally though).. so nothing out of the ordinary I'm afraid.. I started out with a lot of stack separators, but that wasn't efficient at all so the final design is the one depicted in the pictures.. After I got into orbit, I decided that Thud Castle would want to orbit the Mun, so I took it there :) Nice challenge!

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