Least ∆V to Circular Jool Orbit.

[vat21s]

Inclination doesn't matter,

Final orbit must be lower than, Vall's Orbit.

To clarify this is a gravity assist challenge, Scoring will be calculated by ∆V saved.

Return is not required.

Scoring system

∆V Expended - 8080ms = Score

Rules

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-No cheating(f12,Kraken-drive,Excessive part-clipping,Infiglider(If that is still possible))

-ISRU is allowed but you must record your Collective ∆V(If you use 1000m/s and go refuel and use another 500m/s Your total is 1500m/s)

-∆V starts counting in orbit. This is a transfer efficiency challenge after all.

-Screenshots of gravity assists are needed(KER or MJ should be open at this time to prove your ∆V usage)

-Screenshot of launch and orbit is needed.

-Screenshot of aerobreaking(If done) is needed.

-Screenshot of Final Circular orbit is needed.(It doesn't need to be perfect...)

-Information and Piloting mods are allowed and recommended.

-Procedural Fairings is allowed ( I believe the stock ones don't secure the cargo well enough. )

=========Leaderboard===========

Edited June 27, 2015 by vat21s
Clarifying rules.

[tutike2000]

From where do we start? LKO or launchpad?

If launchpad, how do we measure delta-v in orbit, given the varied ISP?

[vat21s]

LKO, This is a transfer efficiency challenge afterall.

[smjjames]

Just a thought here, since NTRs and ion engines (and argon if using Near Future) are pretty efficient deltaV wise (more efficient than LFOX rockets anyway), maybe have two separate categories for LFOX or monoprop based and for LF/LH2/Xenon/Argon based rockets.

Edit: Actually, maybe three would make sense, one for traditional chemical rockets, one for the NTRs that use LF or Liquid Hydrogen, and one for the ion based that use Xenon or Argon.

Also, will we have a standardized payload?

Edited June 27, 2015 by smjjames

[maccollo]

Just a thought here, since NTRs and ion engines (and argon if using Near Future) are pretty efficient deltaV wise (more efficient than LFOX rockets anyway), maybe have two separate categories for LFOX or monoprop based and for LF/LH2/Xenon/Argon based rockets.

Edit: Actually, maybe three would make sense, one for traditional chemical rockets, one for the NTRs that use LF or Liquid Hydrogen, and one for the ion based that use Xenon or Argon.

Also, will we have a standardized payload?

It's not a mass fraction challenge, so it doesn't make a difference, except that the ion engine will be at a severe disadvantage due to it's low TWR.

More importantly the "-∆V starts counting in orbit." rule can be exploited pretty hard by launching into an extremely high suborbital trajectory, like all the way out to Minmus high. Such an extreme example obviously violates the spirit of the rule, but what if I start from a 70x200km orbit? I would specify minimum PE and max AP values.

[smjjames]

How about 1000km x 1000km roughly? Main reason being to be able to go at max warp to get to the departure point.

Also, how is it a severe disadvantage? we aren't going for fastest circularization here. I want to try an ion engine anyway.

Still, given the differences in the way that the different engine types perform, it still makes sense to make categories for those.

edit: If you drop a stage without burning all of the fuel, does that count against or towards the deltaV saved? It's the stage that propels my main stage to Jool from Kerbin orbit around 1k km if you're wondering.

To clarify further, the white tanks are the stage that I'm leaving behind after my correction burn:

Does the deltaV left behind in that stage count towards my score? I'm not trying to exploit a loophole or anything, I actually realized the potential issue after launch since nothing was said about dropped stages. In theory, one could use a stack of 5m (or 10m using tweakscale if you want to get ridiculous) tanks to launch a small probe out of Kerbin orbit for a huge deltaV savings because of the deltaV left behind in the 5m tanks.

Edit: Oh hey, MJ has the ability to show deltaV expended, makes recording expended deltaV easy, I'm going to restart the attempt so that I can record using that.

Edit2: Crap, having some issues related to Nerteas heat control mod, or maybe NFE, not sure.

Edited June 27, 2015 by smjjames

[smjjames]

Anyways, part one of the journey, LOADS of images.

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I accidentially reset the expended deltaV readout without intending to around halfway.

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Edited June 29, 2015 by smjjames