Jeb Needs No Throttle.

[mileshatem]

The Challenge:

Achieve a 100km circular orbit with continuous full throttle until engine shutdown. (Jeb is not a patient man)

Leaderboard:

1. Respawn - 59.517 (117.333 x 90.994)
   
2. soranno - 42.264 (146 x 113)
   
3. -
   

Almost Didn't Cheat-erboard:

1. soranno - 57.611 (156 x 147)
   
2. -
   
3. -
   

The Rules:

• Stock parts + Kerbal Engineer Redux (recommended, but not required) only, no MechJeb, no .cfg edits, no anything else
  
• No debug
  
• No RCS thrusters (though you may use tanks as ballast if you wish)
  
• No coasting between stages (<2 seconds between burnout/shutdown of one stage and ignition of the next)
  
• You may not reignite any engine (you may shut them down, but if you're going to light another afterward it still needs to happen within the 2 seconds from the above rule)
  
• Minimum thrust-to-weight ratio is 0.5 relative to Kerbin sea level for all powered flight (As I said, Jeb is not a patient man)
  
• You must be able to view at least part of the prograde marker on your navball at all times while under power (no "spin until apoapsis", but still allows sharp turns)
  

The Scoring:

Scores will be determined by the following equation (kilometer units):

3/(eccentricity + 0.03) - 0.5*abs(100 - (apoapsis + periapsis)/2)

Or, if you only have apoapsis and periapsis data the equation can be written as (again, kilometer units):

3/((A-P)/(A+P+1200)+0.03) - 0.5*abs(100-(A+P)/2)

Note that negative scores are definitely possible and nothing to be ashamed of, burning straight to any orbit is an achievement!

Exmple scores:

• 100. for a perfect 100km circular orbit
  
• 97.4 for 100 x 99
  
• 78.2 for 100 x 90
  
• 45.6 for 125 x 75
  
• 75.0 for 150 x 150 (it's better to be circular than dead on for altitude)
  
• 0 for approximately 214km x 100km
  

To get things rolling, after about 15 attempts, here's my best thus far: 162.575 x 82.4, Score: 23.85. The images are large, so I've linked rather than imbedding: On the Pad - After MECO.

If this is a repeat of a another challenge please let me know. I did a search and found nothing, but I could have just searched poorly.

Edited May 9, 2013 by mileshatem

[soranno]

clarification please. Is it required that we are on full throttle until our engines shut down due to fuel depletion, or may we choose the moment to cut power, even if we have fuel remaining?

[iamaphazael]

[*]You must be able to view at least part of the prograde marker on your navball at all times while under power (no "spin until apoapsis", but still allows sharp turns)

Ah, you sneaky bugger! This was the first thing that came to mind. Sounds like an interesting challenge. I'm going to give it a shot

[mileshatem]

clarification please. Is it required that we are on full throttle until our engines shut down due to fuel depletion, or may we choose the moment to cut power, even if we have fuel remaining?

You may cut your engines. Just keep in mind that once you do, you either have to dump the stage and light the next, or (hopefully) be in orbit. I was going to originally only allow one "shutdown" event for the whole flight, but I sees no reason why earlier stages couldn't be shut down and discarded early. Though if people start abusing that combined with the "two seconds to light the next stage" to coast I may have to adjust the rules. The main reason the two seconds is there is so people have a bit of time for radial stages to move away.

[Ninety-Three]

Minimum thrust-to-weight ratio for any stage is 0.5 at Kerbin sea level (As I said, Jeb is not a patient man)

Are we allowed to have a final stage consisting of say, a decent engine and an ion drive? Long after the engine burns out, we'll have ion power to make fine adjustments.

[mileshatem]

Are we allowed to have a final stage consisting of say, a decent engine and an ion drive? Long after the engine burns out, we'll have ion power to make fine adjustments.

Nope, that undermines the point of the challenge (powering straight to orbit). All powered flight should be done with a TWR>0.5 relative to Kerbin sea level. I'll edit my rule for clarity.

[soranno]

got a couple. one to 146kmx113km, that I calculated to be 45.75 points

then later a 156x147, a viewer on my stream kindly calculated that one for me(my head had exploded) as 59.739

however in that one I swung right around to retro for about half a second right at the end

[mileshatem]

got a couple. one to 146kmx113km, that I calculated to be 45.75 points

then later a 156x147, a viewer on my stream kindly calculated that one for me(my head had exploded) as 59.739

however in that one I swung right around to retro for about half a second right at the end

Nice work! I'll edit the leaderboard when I have access to a computer that hasn't blocked these forums or when my phone isn't nearly dead. Though I might have to add a second leaderboard for "almost didn't cheat" scores

Edit - updated the leaderboard, although I got calculate slightly different scores when I plug your A&P into my spreadsheet (probably just roundoff in your altitude numbers?) I've used my calculations for consistency moving forward.

Edited May 8, 2013 by mileshatem

[Respawn]

After some badly designed rockets i had a couple of ok attempts with a verry basic 2 stage design.

#1 Ap: 117,333 Pe: 90,994

#2 Ap: 119,887 Pe: 93,458

(58-59 ish points i think..) if i got the scoring system right..

4x speed video of the 2 attempts -> http://youtu.be/lphlNCqVnmo

[tstehler1]

One of my nuclear long-range ships could probably do this... I officially have something to do on Friday