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Flea SSTO efficiency challenge


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Description

Having recently created a simple shuttle spaceplane: the Flea SSTO (Basic) I found that it had a very large fuel budget for simply getting to orbit. This challenge besides testing your ability will find out 2 things:

1) how large of a budget does the shuttle SSTO really have

2) What is an efficient ascent profile for an airhogging SSTO (8 vents/1 jet) with good TWR.

1qgRluN.jpg

The challenge is simple: get the Flea SSTO (Basic) into an orbit with Pe above 100k for the least fuel possible

Scoring will be decided as: liquid fuel + 2x oxidizer on reaching that orbit

For example in the image below I achieved orbit with 185 liquid fuel and 98.44 Oxidizer

OrGGp5C.jpg

So my score is: 185 + 2x98.44 = 381.88

Rules

The link in the description provides the craft in stock form but to this you can attach either the Engineering Redux mod(as I have in the sample) or MechJeb

No use of FAR or gravity hack

Post an image showing your Pe above 100k and also the resource bar at the top for all to see the score.

Also include a short description of the ascent profile you used to reach that orbit efficiently. Ex:

Ascent profile: I climbed at full throttle to about 20k at a 45* angle and had my Ap reach about 28k. I leveled off keeping my Ap around 28k then slowly bringing it up to 30k. Around the 30-31k mark I also had to start throttling the engines back to avoid burnouts. I simply let the speed build up and slowly let my Ap climb to above 110k while keeping the angle of attack very shallow (5-10%). Kept doing this all the way up to around 50k throttling engine down slowly then at 48-50k shut down jet+vents and waited for my Ap which went to around 95k to bring first Pe all the way up to 102k then waited for new Ap and brought Pe up to 102k also.

Leaderboards

1 - carazvan 381.88

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Since in a shuttle you likely want to match orbit with a spacestation or another craft you want more space deltaV so I figured I'd give a higher ratio to the rocket fuel.

An optimal score would be jet fuel left + 2x rocket engine fuel left.

Separating the liquid fuel into what fraction was used via the rocket and what was used via the jet would require the following:

liquid fuel used by rocket: lfr = (oxidizer/110)*90

score = (liquidfuel-90) + 2*(oxidizer + (90-lfr))

You can see how this looks more confusing so I figured lets keep it simple and simply do liquid fuel + 2*oxidizer.

Most ascent profiles that don't go through all the jet fuel will be similar and doubling the oxidizer should still give priority to craft that keep more space deltaV handy.

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