Thrust KSC Land Speed Challenge

[ihtoit]

Following the failure of Werner von Kerman to design and build a supersonic airbreathing jet that didn't use the highly experimental and shockingly expensive Procedural Fairing technology, it was decided that the developments he did come up with were to be put to a more sporting pursuit: that of land speed records.

The Challenge:

Build a car for a speed run along the length of the KSC runway.

Rules:

- MUST start and finish on the runway.

- MUST have at least one Kerbal on board. Probe cores permitted, but you better have a Kerbal in an armchair if you do.

- MUST use a liquid fuel rocket (no nukes though) as your primary method of thrust.

- MUST NOT at any point leave the runway surface. The instant it does, your run is over.

- MUST NOT go off the end of the runway - your speed run must leave enough runway to slow to a stop while still on the tarmac. You may use retro rockets, however these MUST be the solid fuel rockets that burn until they run out.

- Your speed run MUST finish with your car fully intact: no jettisoning parts, no clamps.

- NO welding, unbreakable joints, or any other anti-vehicle-shattering mod. Bits falling off is a run-ender.

- NO infinite fuel.

- NO procedural fairings. Mach 4.stupid dragsters is not the idea here, unless you can achieve this without artificially zeroing parts drag.

- Please indicate if you use MechJeb or any other active flight control system.

- I am aware that FAR drastically alters drag characteristics, I am also aware that it alters lift characteristics to a similar degree. Both advantages in flight, total disadvantages on wheels. Or skids.

Scoring:

Post-run F3 screenshot and a shot of your vehicle at the start and end of its run. Video would be nice, especially if you have a spectacular run.

Bonus 100 points if you make an immediate turnaround and successful return run of at least 75% of your West/East (outward) run speed.

Speed in m/s.

Non-FAR

1. Michaelo90 in the Dragster V6 450+, (453m/s)

2. Michaelo90 in the Dragster v5 440+, skids not wheels (441m/s)

3. Minimatt in the Unnamed, (433m/s (using Realchutes)) (425m/s (without))

4. MiniMatt in the Land Speed 8, TWELVE Mainsails, you say? (423m/s)

5. MiniMatt in the Unnamed, SIX Mainsails of Kerbalicious insanity! (416m/s)

6. Michaelo90 in the Dragster V4.0 400+, (415m/s)

7. War_Lord_Kevin in the Dragsta for 402m/s. Three posts and you make a leaderboard! Kudos!

8. Minimatt in the Triple Mainsail Sphincter Twitcher*, (397m/s)

9. Rhomphaia in the Mk.II, (374m/s) (nice use of active downforce there!)

10. Rhomphaia in the Mk.II, (345m/s)

11. Rhomphaia in the completely stock Dragster, (268m/s)

12. Will in the Unnamed, (264.4m/s)

13. Eli in the Unnamed, (212.7m/s)

14. Zac in the Unnamed, (203.8m/s)

15. Mr. Professional with the Bad Enough Dudez in the Iron Chef Pointy Rockety Sideways-Skiddy Thingy, (191.7m/s)

16. ihtoit in the Spirit of Kerbin, (184m/s)

*yeah, I named it

FAR

1. michaelo90 in the Insanity Racer FAR V3 700+, (740m/s)

2. Minimatt in the Unnamed, (503m/s)

3. Soda Popinski for an eyewatering skid run in (I'll name it) The Manta, (467m/s)

4. Koolkei in the Dragor 2, (435m/s) (no bonus for the interesting return trip because you didn't actually turn around nor did you make it at at least 325m/s)

5. Soda Popinkski in the Yoyodyne Buckaroo Mk. idon'tknowanymore , (377m/s)

6. Soda Popinski in the Yoyodyne Buckaroo Mk.XVII, (374m/s)

7. Bobnova in The Stubby One, (316m/s)

Spectacular Failures

1. ihtoit in the Thrust KSC: 175m/s and some floor gymnastics

2. Soda Popinkski in the Yoyodyne Buckaroo Mk. idon'tknowanymore (with video), kissing runway lighting fixtures and laughing like a maniac all the way down.

3. The Bad Enough Dudez with their Iron Chef Episode I: The Phantom Runway take on this challenge - fantastically funny!

4. The Bad Enough Dudez in Iron Chef Episode II: Attack Of The Asymmetries, following up on that fundamental question of the need to slow down.

5. The Bad Enough Dudez demonstrating how to crash at 8m/s in Iron Chef Episode III: Revenge Of The Sepratron.

6. The Bad Enough Dudez having fun with Mainsails in Iron Chef Episode IV: No Hope Whatsoever (guys, can you post or hint at the uncut Zac run at 231.3m/s? I think I blinked and missed it!)

Edited July 1, 2014 by ihtoit
forgot how to count upward!

[ihtoit]

As the OP, I'll post all my entries here.

My Failrun:

Thrust KSC: 2 Wildcat V rocket engines, loads of fuel (more for weight than anything else), two pairs of stock winglets set to neutral profile for downforce - which actually works *very* well with stock ASAS and MechJeb.

Got to speed, fired the retros (4 Ullage motors which is WAY too much) and deployed the chutes (waste of time, I suggest you get the Real Chutes mod if you decide to brake using chutes), and a bit of mad flipping later, only one part fell off. However, seeing as the vehicle landed off the runway, this would actually class as a fail even if that winglet stayed on:

F3 screen:

So there's your yardstick on something that took me all of a minute to build. 175m/s and a fail.

Edited February 14, 2014 by ihtoit

[ihtoit]

Thrust KSC II: 175m/s and a successful run. Same setup as Thrust KSC I, only one pair of Ullage motors this time, and a safe brake.

Finally, proof that it did not leave the ground (in the MET clock still reading zero):

[ihtoit]

Spirit of Kerbin: 184m/s and stopped right at the end of the runway!

MechJeb and Mk.I SAS, fixed trailing edges from B9 and stock winglets, powerplant: Maverick 1D from KWRocketry. Needed 4 Ullage motors to stop (which they did, didn't even have to tap the brakes until they burned out!), 6 would probably be overkill from 184m/s but it'd allow a slightly longer, hence faster run I think...

Edited February 14, 2014 by ihtoit

[m1sz]

Might give it a try when I have time

Are fairings allowed?, and if they are, can we eject then?, I guess the second answer is no, because then it's a stage!

[Rhomphaia]

The Dragster - completely stock. Mk2 cockpit SAS

Javascript is disabled. View full album

267m/s east

268m/s west

Edited February 14, 2014 by Rhomphaia

[ihtoit]

Might give it a try when I have time

Are fairings allowed?, and if they are, can we eject then?, I guess the second answer is no, because then it's a stage!

short answer: no. From the background, Werner had to use developments made without PR so that carries over. Rules updates to clarify. Also, no, any bits falling off is a run ender. That includes ejecting shrouds etc.

Edited February 14, 2014 by ihtoit

[MiniMatt]

Hmm, just did a quick initial 217m/s completely stock thinking it was pretty good, alt-tab back to this page to find Rhomp already smashed it (oh and those engines look like a cluster of 48-7S to answer ihtoit's question).

Be right back

[Rhomphaia]

Hmm, just did a quick initial 217m/s completely stock thinking it was pretty good, alt-tab back to this page to find Rhomp already smashed it (oh and those engines look like a cluster of 48-7S to answer ihtoit's question).

Be right back

Indeed they are.

[Bobnova]

Here we go, 316m/s.

Mods are numerous, TAC, DE, FAR, Kethane, etc. The only one that is actually relevant is FAR I think.

No mod parts were used.

Pics:

Javascript is disabled. View full album

Two stage seperatron retrorockets, as a single stage with all of them results in unpleasantness.

Many prototypes crashed, one managed to hit the control tower about 60% of the way up the tower.

[Rhomphaia]

Not to be outdone, the Dragster MK2 (or should that be Mach 1). Still stock, Downforce provided by winglets and angled 24-77s. braking assisted by air intakes and a couple of seperatrons

345m/s. no return this time, and with a lot of fuel left, and quite a bit of runway so I can probably top that, keeping it on the runway is hard though

Edited February 14, 2014 by Rhomphaia

[ihtoit]

crackin' little firecracker... leaderboard updated

[Bobnova]

Mine was human controlled, no mechjeb on there driving.

I like the Mk2, I may have to steal some ideas

[Rhomphaia]

Mine was human controlled, no mechjeb on there driving.

I like the Mk2, I may have to steal some ideas

Steal away

I think it is FAR that gets you put in the controlled section.

In other news while testing the limits of the Mk2, Bob managed 411m/s before he ran out of fuel... Unfortunately not before he ran out of runway... Or even ground.

He hit the water at 45m/s and I accidentally hit tracking center instead of revert.

so Donmore takes the wheel for this one

374m/s

[ihtoit]

Steal away

I think it is FAR that gets you put in the controlled section.

In other news while testing the limits of the Mk2, Bob managed 411m/s before he ran out of fuel... Unfortunately not before he ran out of runway... Or even ground.

He hit the water at 45m/s and I accidentally hit tracking center instead of revert.

so Donmore takes the wheel for this one

374m/s

Yep, pretty much anything beyond passive SAS (stock reaction wheels and the like, above about 20.0 torque per axis) or anything that actively adjusts aerodynamic profile such as MechJeb gets you on the "controlled" board.

You've got a good run there at 374, leaderboard updated.

[Bobnova]

FAR replaces the aero model, but there's no active control like mechjeb.

I'm fine being in a non-stock category, it makes sense as FAR changes the drag model a lot, I'm just trying to understand why I'm in one called controlled when there aren't any extra controls.

[ihtoit]

ah gotcha, ok no problem I can move you if you want? I didn't actually know whether FAR actively controlled the aerodynamics or not, thanks for the clarification

*Rules adjusted slightly to acknowledge this new information.

Having thought about it a bit, I've decided not to ban FAR even given its radical rehash of the drag model, because it also rehashes the lift model (to what extent I know not of either, it would be interesting to find out on the same vehicle with and without FAR - any volunteers for a test-it-to-death model?); the reason PF is banned is because it allows you to minimise drag to basically zero (yes, Mach 4.stupid at 1000m horizontally would ordinarily cause an aircraft to explode due to friction) and maximise downforce to produce a supersonic wheeled missile*. Hence, PF=OP.

*also why I dropped in the bonus challenge of turning around and speedrunning back to prove it isn't just a rocket on rails.

Edited February 15, 2014 by ihtoit

[Bobnova]

I'm totally fine being in a different category, it's a fun challenge regardless of where my score is

I don't know to what extent the drag is changed at sea level with FAR. I know that as you ascend the atmosphere density (and thus drag) drops off much faster than stock, but at sea level I have no idea.

I may try to get the modded kOS working and see if I can make a 100% automated speed vehicle just for giggles.

[Soda Popinski]

Damn, when I started this, I thought I only had to beat 345 m/s.

Anyways, here's 354 m/s. I went with a different tactic. I found tires too delicate, so I went with cubic strut skids. Also, I wanted to use a Mainsail.

Only relevant mods are FAR and RealChutes. I tweaked the SRBs to only hold about 30% fuel.

Edit: This was the "Yoyodyne Buckaroo mk 17." Here's a video with some choice examples of a few of the other marks.

Edited February 15, 2014 by Soda Popinski

[ihtoit]

I'll have to think about this one, fuel-tweaked SRBs you say?

OK, I'll let you have that. Only because the RT10 has an abysmal TWR compared with an equivalent-weighted stack of Sepratrons, at any fuel level.

(nice run, by the way - what was the g-reading? Looked like approaching 15g)

[Soda Popinski]

I'll have to think about this one, fuel-tweaked SRBs you say?

OK, I'll let you have that. Only because the RT10 has an abysmal TWR compared with an equivalent-weighted stack of Sepratrons, at any fuel level.

(nice run, by the way - what was the g-reading? Looked like approaching 15g)

Cool. Thanks.

Looks like 11.7g was the max. I'm surprised my Kerbal survived, as I'm running DRE. Oh, I called my "ship" the "Yoyodyne Buckaroo mk 17."

I plan to upload a video on the iterations getting up to mk 17.

Edited February 15, 2014 by Soda Popinski

[MiniMatt]

Got a completely stock 367m/s with a bit of runway to spare. There might be a teensy bit more to squeeze out of this one:

EDIT: There was a teensy bit more! 376m/s completely stock:

EDIT 2: 397m/s! That's near as damn it a quarter mile every second. One mainsail took me to 376, took three mainsails to get to 397. Still completely stock:

Javascript is disabled. View full album

Upside down canards provide some front downforce as it's rather tail heavy. RAM air intakes toggled shut on first stage (ie. starting the mainsails) for low drag. Trial and error informed initial tweaked fuel load of 180 per 360 capacity tank. The moment fuel runs out action group 1 opens the ram air intakes to add drag and - counter-intuitively - engages front brakes (again, much testing and many explosions to reach this setup). When speed has descended to around 250m/s the 2nd action group fires a pair of retro seperatrons (fractionally angled upwards) and engages rear brakes. The moment those seperatrons burn out action group 3 triggers a further three pairs of seperatrons.

EDIT: Craft file for 397m/s triple mainsail beasty is here, should anyone be interested.

Edited February 15, 2014 by MiniMatt

[m1sz]

I made some testings, my car wants to fly when going over 400m/s

When I can, ill try to fix it. Also, are aerobrakes allowed? (the B9 ones)

[Michaelo90]

I have one coming up soon, just have to record it

[ihtoit]

I made some testings, my car wants to fly when going over 400m/s

When I can, ill try to fix it. Also, are aerobrakes allowed? (the B9 ones)

Yes. Further clarification: automatic, active flight control system deployment (eg via MechJeb) counts as a controlled run. Manually deploying them through action groups or individual clicking doesn't count as a controlled run, that's an uncontrolled run.