Kerbodyne Touch & Go Racing League

[hoioh]

Sweet! I was just about to crush your dreams with 4:03 with a 2-engine plane. Very nice runMerandix! Your screenshot displays 4:00 flat though. (still faster than mine if even by a hair)

Here's my Formula Stock entry video:

My 4:03 video won't be uploaded till tomorrow. (internetzzzzzzzzz.....)

[Merandix]

hoioh, you should scroll down a bit more

First IMGUR batch is the 4:11 run (the screenie you're referring to actually shows me still going 68 m/s), the next one in that particular batch of images is the 4:11 one

Second Imgur = 3:58

Third batch = 3:55

Anyway, I'm off, maybe I'll check back again later tonight I expect to see a sub 3:00 by tomorrow lol.

[Captain Sierra]

I'm going to give altitude a shot and switch out my center engine for a turbojet. Still have a lot of tuning to do but as a sport plane (not just a speedrun plane) it works GREAT!

EDIT: Also a tip for people. If you can hit 250m/s or more, 30L of jet fuel per engine is all you need. I'm running the tank tweaked down to 90 for three engines and I can land with fuel to spare (but my margins are only acceptable for speedrun purposes and would not be tolerated on most designs).

Edited January 18, 2015 by Captain Sierra

[hoioh]

We're in the same timezone, Merandix, heck we're in the same country! so no, I will not be attempting to make a 50 engine craft to get below 3 minutes tonight I'll be sleeping, then working, then maybe I'll attempt another go.

I think 4:03 is a very respectable entry for which I will be submitting my video for tomorrow morning. In the meantime I will be flying Bertha my 90 ton SSTO for the K-Prize Maximalist award.

[Captain Sierra]

I built a 2-seater FAR plane to try this on and I found out why the example craft uses a turbojet. FAR nerfs the absolute living crap out of the stock jets.

Another problem you run into is that you compress. I was cruising at nearly 600m/s with just 2 engines and you lose all control authority when that happens. There's definitely speed to be had when you're not flying in the soupmosphere, but the skill ceiling is a lot higher.

EDIT: What I thought was enough air brakes ain't coming close to cutting it.

Edited January 18, 2015 by Captain Sierra

[Merandix]

Lol, we seem to be 'clashing' a lot today...

@Captain Sierra

You could probably manage with 75 fuel, depending on the weight of your craft. Also, I think going higher would be beneficial for you... I suspect your craft is easily capable of more speed at higher altitudes.

Also, FAR uses more realistic aerodynamics. And aerodynamics go weird in reality when going supersonic. FAR likely models this. So yeah, a bit more thought should probably go in... Though, supersonic flight in stock also reduces control... In particular hypersonic speeds... I frequently need half a continent to make a 'minimum' radius turn when going 1700+ m/s lol

Edited January 18, 2015 by Merandix

[Captain Sierra]

Lol, we seem to be 'clashing' a lot today...

@Captain Sierra

You could probably manage with 75 fuel, depending on the weight of your craft. Also, I think going higher would be beneficial for you... I suspect your craft is easily capable of more speed at higher altitudes.

75 fuel leaves me with a lot less room for error than I'd like. If I go the high route I'm sticking with 90 fuel. I will certainly try it.

In other news I managed almost 3 minutes in one of my FAR trials. Aero failures is making it really hard to slow down.

[Wanderfound]

Well, this one certainly got popular overnight.

Some rule clarifications for Formula One: as was correctly assumed (kinda) by the competitors, tweaking the fuel load is against the rules. I'm fine with people tuning control surface settings, though; in FAR, that could extend as far as trying to use control surfaces as spoilers/airbrakes. No other mods to the plane, though; no adding/deleting/relocating any parts, no messing with the FAR mass tweakables.

In the Open classes, the use of drag chutes is obviously hugely beneficial. Should we run a separate leaderboard for non-chute planes? There's more piloting skill involved in slowing down aerobatically.

Y'all are welcome to have a go at the aerobatic contest as well (see link in .sig), or the Loop & Land Sprint (http://forum.kerbalspaceprogram.com/threads/107547-The-Kerbodyne-Loop-Land-Sprint). The craft for that is the same as the Formula One plane here.

Looking forwards to some FAR entries. I'd recommend trying the touch & go a bit slower than I used in the demonstration run for the first few runs. The screenshots don't fully catch it (I was too busy for F1), but shortly after hitting the island runway I was flying backwards towards the hillside about 20m off the ground...

Edited January 19, 2015 by Wanderfound

[Captain Sierra]

I can understand why. I put it into a flatspin after my first FAR touch and go, which I did at nearly 300m/s. SOmehow I saved it and made it back to the runway, only to crash in a fiery death.

[Wanderfound]

Had a serious attempt at the FAR Open Class: 4 minutes, 7 seconds.

Full flight at http://s1378.photobucket.com/user/craigmotbey/Kerbal/Challenges/Kerbodyne%20Air%20Race/Open%20run%201/story

[Captain Vlad]

Stock open class. I feel the time will only be decent if the parachute/no parachute thing is split (and maybe not then), but either way it was a hell of a lot of fun. Craft is the JA-2 Super Sparrow, it's my 'randomly fly around for fun' jet. Overall time 4:48; no parachutes, one standard jet engine.

Spawned in and (almost) ready to roll.

This plane takes off almost as soon as the jet's making full power...like 60-80 mps, so I didn't have to roll down the runway for long. Started turning as soon as the wheels were off the ground and barely missed the top of the VAB as I accelerated out, which I sadly did not get a screenshot of. Instead, here's the plane climbing up to about...erm...I'm not sure. I got her up to 2-3,000 meters during the outgoing leg, not sure about the exact altitude.

Did the outward leg as fast as I could, but I feel I could've got a better time if I'd let her climb a bit more. The 311 mps you're seeing her was right before I basically just dove for the ocean and pulled up a few meters of around the same level as the island runway...which I'm always uncertain of because I always forget to put markers flags out there.

I'm not 100 percent sure this shows the actual wheel contact because I bounced slightly, then came back down to the ground and kept rolling at 161 mps. You can see this was Annie's absolute favorite part of the trip.

On the way back I'm convinced I made better time because in the haste to turn around, I climbed a bit higher and hit a speed sufficient to start to see the visual Mach effects. Even descending to 2,000 meters or so was enough to slow me by 20-30 mps, which I wasn't really complaining about at the time because the runway landing was the part I was having trouble with in my practice runs.

I cut the engine to shed speed as I had my final suicide dive toward the runway. Landed fine, but braking from landing at 100 mps or so took forever...consider me a proponent of a parachute and non-parachute class.

That was a terrible amount of fun, Wanderfound. Great challenge idea.

[Wanderfound]

Okay: due to the hint of public support, I am now making an autocratic ruling (which will be immediately reversed if it's greeted with an overwhelming storm of protest ) that we'll separate each division into chute-assisted and no-chute categories.

Just think of it as now having twice the chance to win a division.

Am I right in thinking that the only chute-aided entries so far are mine and hoioh's?

- - - Updated - - -

Sorry to sound slightly negative, but the 'Formula One' league deserves a nippier plane to be honest... We have almost 10 times the fuel we need aboard.

The point of the F1 plane was to get a level playing field, rather than the fastest possible plane. Plus I'm planning to make this a race series​ if folks stay interested, and some of the future ones might be a bit longer-distance.

- - - Updated - - -

Also, FAR uses more realistic aerodynamics. And aerodynamics go weird in reality when going supersonic. FAR likely models this.

Yup, it does. The main immediate effect of crossing the sound barrier is a slight decrease in drag and an increase in stability (CoL shifts rearwards at supersonic speeds). It's a bit bumpy as you cross it, though.

- - - Updated - - -

General vote: should we allow preflight alteration of fuel levels for the Formula One plane or not? It's bothered some people, and I don't mind either way.

Edited January 19, 2015 by Wanderfound

[Captain Vlad]

Am I right in thinking that the only chute-aided entries so far are mine and hoioh's?

There's a couple more. Though some pilots seem to have runs with both a chute and non-chute version of the same plane. Vincent and CaptainSierra both had some chute birds.

[Wanderfound]

I built a 2-seater FAR plane to try this on and I found out why the example craft uses a turbojet. FAR nerfs the absolute living crap out of the stock jets.

Another problem you run into is that you compress. I was cruising at nearly 600m/s with just 2 engines and you lose all control authority when that happens. There's definitely speed to be had when you're not flying in the soupmosphere, but the skill ceiling is a lot higher.

EDIT: What I thought was enough air brakes ain't coming close to cutting it.

Airbrakes are good for adding a little gentle deceleration over a long glide, but they ain't gonna cut it at race pace. If you aren't going with chutes, then it's going to take some aerobatics: S-turns, loops, climb/stall/dive cycles, etc.

[hoioh]

Here's my 4:03 run video, as promised:

• 
  

In regards to fuel levels, you already have my 2 cents. I think it's not a change to the craft to drain the fuel in the same way that I can buy a car with an empty gas tank or a full one and it's still the exact same car.

Nice thinking on the chute separation Wanderfound, I think that's a fair way to treat it.

[Wanderfound]

A chute-free FAR Open Class run: 4 minutes, 19 seconds. Airbrakes work better than I expected.

Full flight at http://s1378.photobucket.com/user/craigmotbey/Kerbal/Challenges/Kerbodyne%20Air%20Race/Open%20nochute%201/story

--

Also: new arbitrary ruling, you are now allowed to alter the fuel levels on the F1 plane. As usual, mass protest will reverse the ruling if necessary.

I'm about to set up the second course; you can keep going on the first as well, but this should give a new challenge for those who've already had a bunch of attempts at the original.

Edited January 19, 2015 by Wanderfound

[Captain Vlad]

Did another run. Assuming the grass next to the dirt at the island airfield counts, reduced time to 4:34 via the 'don't actually slow for the wheel contact' method, while also climbing more on the run in.

The touch and go at 251 mps.

Hit 350 or so in the return dive before the low altitude air started to really slow me down.

And landed, 4:34. Not bad for one engine, I don't think.

[Merandix]

Ok, about your plane, MAYBE I should've done the Formula One first, and the open class afterwards. Because yes, it will feel like you're flying an airliner compared to the likely performance of crafts of the open class. I fully agree with you on a level playing field though. Therefore I kind of feel like tweaking fuel (and thus take-off mass) is one step too far. I think it SHOULD be allowed to tweak anything you can tweak as a pilot, but she's fuelled up in the SPH... so that's mechanics work in my mind. Also I feel like allowing fuel to be tweaked is a bit more (Sorry hoioh, not that I want to disagree so much, but I honestly believe this is a more straightforward ruling).

I'm still out on the parachutes. They do add mass and drag. But especially in the single engine category, they do make a significant difference in getting the plane to stop. Because again, that little plane really REALLY liked to fly, and didn't want to stop

[Wanderfound]

Incidentally, the other reasons for the relative speed of the F1 plane:

* There'll be other races; the F1 needs to be a generalist, not built for one course.

* I wanted to make it a relatively novice-friendly ship, so anyone can have a go.

* The stock one is just a modified version of the FAR original. The FAR version is actually rather impressively quick. A three-engined version was substantially slower thanks to increased mass and drag.

So far, we're one each way on the fuel level thing, with me leaning towards allowing it. After all, race drivers do it all the time, even in tightly-controlled series like F1.

Anyone care to chip in with some tiebreaker votes?

[Captain Vlad]

So far, we're one each way on the fuel level thing, with me leaning towards allowing it. After all, race drivers do it all the time, even in tightly-controlled series like F1.

On the other hand, F1 has years where the cars have to be fueled to the finish, etc. My first thought when you posted about the fuel was actually 'an arbitrary fuel requirement actually sounds very FIA!'.

My thoughts are that, for the F1 Stock version, everyone should be flying the same plane in the same condition -- whether that's fully fueled or at some percentage set before the challenge. It's the spec series, like A1 Grand Prix was, while the 'Open' is more like Ferrari building their own car within certain parameters.

[Wanderfound]

I'm about to post a video demonstrating the next course.

So far, it's "take off, turn around, through the big pass in the mountains then turn around sharply and come back through a narrow cleft". It's fun, but what it doesn't have is a touch & go...

How committed are we to the name of the series? Watch the video before making up your minds, but we could easily add a bit at the end where you have to do a touch & go on the KSC strip, then fly out past the beach before turning around to land from the water side. Or even make it so that you have to go do a race 1 style touch & go at the Island strip before coming back to KSC, maybe with a bump at KSC on the way.

But that would add more time to a race that took me 4:48 to do, and I want to keep these short enough that it isn't super-frustrating if you stuff up right at the end. So, I dunno: keep it to a five minute race, or add a little flourish on the end? If we want the bump and go, should it be KSC, Island, or KSC and Island?

Edited January 19, 2015 by Wanderfound

[Merandix]

Just post that as a separate challenge, I'm sure there's more people who'd like that.

If you want to make a race series, make a dedicated topic for that, and perhaps have times for each individual leg as well? Would keep this purely for touch and go challenges...

A touch and go at the helicopter landing pads on top of the VAB sounds challenging too Nice tight spot to touch the wheels on. So much potential for just touch and goes in this topic, and you could just post them as different legs to a competition. Perhaps adding all the best times of individual races together for an all-round championship touch & go?

edit: though I would still keep the classes seperate

[Wanderfound]

Here we go: track 2 demonstration, 16 min long 'cos the videocap slows my computer down a fair bit. The key bit is the bit between five and nine minutes.

I'm still thinking that would work nicely as the first leg of something with a touch & go at KSC though.

Edited January 19, 2015 by Wanderfound

[Merandix]

Video is private?

[Wanderfound]

Video is private?

Dangit, I fixed that and then Youtube changed it back.

Should be right now.

- - - Updated - - -

The thought behind it was that the KSC strip is open enough that a touch & go there would have to be super-fast to be interesting. To go super fast, you need a runup; out to the mountains and back seemed like a good way to do the runup (ducking through a narrow pass is always fun). It's the nearest landmark apart from the island.

So how about mountains and back (through the passes shown in the video), with a touch & go at extreme speed on the KSC strip before turning around over the water and coming back to land? That should be doable in under six minutes, it's got plenty of maneuvering in it, nice scenery and it's different enough from the first not to be repetitive.

Then we could do a slower, tighter track (e.g. take off, tap the helipad, land back on the runway) as a contrast for the third one.

Edited January 19, 2015 by Wanderfound