High speed stock Aircraft challenge.

[TheTripleAce3]

I've been trying to make SSTOs for quite the while, some successful, the vast majority not.

What I have discovered however, is how easy it can be to make stock planes go excruciatingly fast at low altitudes.

Iirc, my fastest plane @10km was a near-orbital bomber project that had been partly, maybe halfway, drained of fuel that went 2104m/s or something like that. It burned to a crisp soon after doing so (at least it was unmanned!) but it was cool to see that it would at least go over 2km/s after dropping payload.

I made it to 2km/s again in another similar craft but the cargo bay housed 2 small TCS systems and I was at 15km this time. Lasted slightly longer before I pulled the airbrakes and ripped the plane back into subsonic speeds once again.

 

Anyways, the main challenge is to make a plane with jet engines (my 2 planes used rapiers only, of which there were 10) go 2km/s, hopefully even 2.3km/s, and keep it in Kerbin's atmosphere. Sub-orbital hops don't count unless you're just burning of fuel to get TWR up.

CATEGORIES:

1. Jets only, low altitude. Air breathing engines only, <15km

2. Jets only, medium altitude. Same as 1, but between 15 and 21km.

3. Jets only, high altitude. Above 21km on airbreathers only.

4. Hybrid, low alt. Jets + one aerospike (or any allowed LFO engine) at or below 15km.

5. Hybrid, medium alt. Same as 4 but between 15 and 19km. 

6. Hybrid, high altitude. Jets + aerospike (or any allowed LFO engine) between 19 and 21km.

7. Hybrid, very high altitude. Above 21km.

8. Rocket only aircraft at low altitude. LFO engines only at or below 13km.

9. Rocket only, medium alt. Same as 8, but between 13 and 18km.

10. Rocket only at high altitude. Between 18km and 23km.

11. Rocket only at extreme altitude. LFO only between 23 and 27km.

12. Jet-Ion hybrid. I just want to see someone do this, surprise me!

13. Limbo. Go +2km/s as low as you can, no cheating, and keep thrust below 1000kn.

RULES: 

0. MINIMUM QUALIFIER SPEED IS 2000M/S SUSTAINED FOR 3 SECONDS FOR ALL CATEGORIES

1. Must be a plane, as in it uses primarily aerodynamic controls and wings. Mk 2 parts are preferred for fuselage in my experience.

2. RAPIERS, for jets only submissions, these engines are not allowed to go into closed cycle at any point. If they do, they are classed as rocket engines rather than airbreathers. This means your run will be counted as a HYBRID category run.

3. Apoapsis height when at top speed should not exceed 30km unless you are doing a power-dive, in which case I ask it be below 40km.

4. Submissions are to be classed by the altitude they are at when they reach top speed, if you reach top speed twice in the same flight, use the lower altitude.

5. Proof of completion is to be in the form of screenshots. If you are not aware, it is possible to have your navball open on the map screen by clicking the arrow at the bottom of the game window. You should also right-click your apoapsis to have it "bookmarked" while setting up your screenshots.

6. For all categories, speed is to be determined with the surface reference on navball only.

7. TCS systems are frowned upon but allowed, it would be hypocritical of me to ban them as one of my designs used them.

8. Bonus: Survival with a manned aircraft at these speeds and altitudes (MUST use stock cockpits, no chairs in service modules!) is likely to be challenging, I encourage you to try it. Detachable cabins are allowed for this subsect of the challenge, although airbrakes are more likely to help.

9. Engines should be of the Small size, or 1.25 meters like the rapiers. Vector is not allowed for this competition for the sake of pushing designs as far as possible, the vector would arguably make this challenge extremely easy at the extreme or high altitude categories.

10. The only mod allowed to be used is Kerbal Engineer Redux for gathering proof of apoapsis height and surface velocity in screenshots. All altered or modded engines or parts are disqualified as are autopilot mods. If I can do it with standard SAS, so can you. 

10b. If you have a question about a modded part i.e. cabin, then ask me. Don't use insanely powerful modded engines or scramjets, that would remove the true challenge from this if you did.

11. Ablative heat shields are allowed, but only one, and it must be at the tiny, or 0.625m size, the same as the small circular air intake. It can not be jettisoned after the material is burnt off.

12. No part clipping of engines. You may put fuel tanks inside the wings and attach engines there, but this will mostly add stress to the wings.

13. Have fun, make any suggestions you feel warranted and I will think about altering the challenge.

Thanks for reading this book of a challenge.

Edited April 17, 2018 by TheTripleAce3
Grammar, added new rules.

[TheTripleAce3]

Scoring will be done in velocity/ SQRT of altitude at time of top speed ( or in screenshot).

Ex:

If your alt was 10km and velocity was 2100m/s then you would take sqrt of 10, which is roughly 3.16, and do 2100 m/s / 3.16 = 664.55 points

Edited April 17, 2018 by TheTripleAce3
Grammar, thank you CrazyJeb. Amended scoring system, thanks again CrazyJebGuy

[CrazyJebGuy]

3 hours ago, TheTripleAce3 said:

Scoring will be done in velocity/altitude.

Ex:

2100km/s / 10km = 210 points.

Think you meant m/s there.

[TheTripleAce3]

5 minutes ago, CrazyJebGuy said:

Think you meant m/s there.

Aye, thanks.

[CrazyJebGuy]

This is my entry, fished up a plane I made for a passenger jet challenge, it's gone 1420m/s at 12.5km, but that only scores 113.6, and i can do better. Here it is, going 690m/s at 102 meters, 690 / 0.102 = 6764 points.

Only used air-breathing jets, later I went and landed. Note: It does have a couple of modded parts, from Airplane Plus, but they don't actually do much, 2.5m cabin and passenger compartment, all the engines, wings, landing gear and flaps are all stock, I'm pretty sure. Built this a few months ago. By the way it seats 22, but only had two on board this flight. It would probably actually go faster if I removed the modded cockpit and went again, but I can't be bothered. Understandable if this disqualifies me.

Might suggest nerfing the payout for lower altitudes. Maybe square root of altitude.

[Andetch]

34 minutes ago, CrazyJebGuy said:

This is my entry, fished up a plane I made for a passenger jet challenge, it's gone 1420m/s at 12.5km, but that only scores 113.6, and i can do better. Here it is, going 690m/s at 102 meters, 690 / 0.102 = 6764 points.

Only used air-breathing jets, later I went and landed. Note: It does have a couple of modded parts, from Airplane Plus, but they don't actually do much, 2.5m cabin and passenger compartment, all the engines, wings, landing gear and flaps are all stock, I'm pretty sure. Built this a few months ago. By the way it seats 22, but only had two on board this flight. It would probably actually go faster if I removed the modded cockpit and went again, but I can't be bothered. Understandable if this disqualifies me.

Might suggest nerfing the payout for lower altitudes. Maybe square root of altitude.

I see the exploit of the maths there. It is the issue with equation scoring like on my challenge. It makes your KEA subjective scoring based on judges personal preferences a lot more attractive.

 

[TheTripleAce3]

To apply for this challenge, crafts must go at least 2000m/s in the categories.

@CrazyJebGuy @Andetch

[CrazyJebGuy]

2 minutes ago, TheTripleAce3 said:

To apply for this challenge, crafts must go at least 2000m/s in the categories.

@CrazyJebGuy @Andetch

You sure pure jets can do that? Turbojet thrust falls off spectacularly over about mach 5.

[TheTripleAce3]

9 hours ago, Andetch said:

I see the exploit of the maths there. It is the issue with equation scoring like on my challenge. It makes your KEA subjective scoring based on judges personal preferences a lot more attractive.

 

I intended for extremely low alts to have very high scores. I can hardly even get to these speeds below 10km but I can do it.

If you can do it, you deserve a high score.

1 minute ago, CrazyJebGuy said:

You sure pure jets can do that? Turbojet thrust falls off spectacularly over about mach 5.

Yes, I have done so before. I'll start fishing on my harddrive for the screenshot of it.

[TheTripleAce3]

Here is my proof of a category 6-7 run.

Rounding up to 25500m for easier maths indicates that my score is 2015 m/s / 25500m = 0.07 with the initial scoring method.

@CrazyJebGuy if we use the sqrt of 25500, 159.6871 (round up to 160), the score = 2015m/s / 160 = 12.59375 rounded up to 13.

[Andetch]

What is the OP's opinion on mod parts? Like the scramjets that you need to be going mach 2 before they even fire up...

[TheTripleAce3]

2 minutes ago, Andetch said:

What is the OP's opinion on mod parts? Like the scramjets that you need to be going mach 2 before they even fire up...

No modded engines. I did this entirely stock, no reason why others can't. 

Modded cabins like the one @CrazyJebGuy used are a tough spot since they can be really heavy and draggy but I'll understand if someone just uses a cabin that looks a little nicer. I said in the rules (#10) that only KER was allowed for getting screenshots and later I said not to clip in extra engines. 

Just be reasonable with it. I'm really trying to push hard on what stock engines are capable of and I know this can be done.

[neistridlar]

I just checked using the infinite fuel and ignore max temp cheats, and above ~ 1km it is simply impossible to go above 2000m/s because the engines simply does not produce any thrust above ~mach 5.8. It varies a little by altitude, at higher altitudes it is lower, and the speed of sound is also lower, so above 17km it is simply impossible to even break 1800m/s with air breathing engines only. So categories 2 and 3 are strictly impossible. For category 1 you are going to burn up long before you reach 2000m/s, so that is also practically impossible.

[Stratzenblitz75]

Here's 2.032 km/s <1 Km. The real trick to doing this is a fairing + sideways heatsheild.

I didn't optimize this very much so someone could probably take the same principle and make faster one.

And yes, it does fly at lower speeds and can be landed without a parachute (although, with much difficulty).

[TheTripleAce3]

1 hour ago, Stratzenblitz75 said:

Here's 2.032 km/s <1 Km. The real trick to doing this is a fairing + sideways heatsheild.

I didn't optimize this very much so someone could probably take the same principle and make faster one.

And yes, it does fly at lower speeds and can be landed without a parachute (although, with much difficulty).

Well that would be 2032 pts right there.

Congratulations on a limbo run.

PS, nice videos on YT.

[Not Sure]

Oh my gosh.. I was gonna ask if ions were allowed, and saw the category. 

People who played with me on DMP know I brag about my Mach 16* ion* plane. 

[TheTripleAce3]

5 hours ago, Not Sure said:

Oh my gosh.. I was gonna ask if ions were allowed, and saw the category. 

People who played with me on DMP know I brag about my Mach 16* ion* plane. 

Pics or it didn't happen.

[Raptor kerman]

Similar and more complete challenge already exists :), looks like a fun take on it though.

[ErikHall]

Venture Star SSTO 

Top speed at an Altitude of 542 Meters: 836,6 Meters/Second

https://ibb.co/jfGKBx

After that, it startet wobbling like crazy and the G Forces destroyed it.

Edited April 26, 2018 by ErikHall
Forgot something.

[Gordon Fecyk]

Ferram Aerospace category?

Still use stock parts, but FAR air frame failures would up the challenge difficulty, and explosive potential.

[TheTripleAce3]

8 hours ago, Gordon Fecyk said:

Ferram Aerospace category?

Still use stock parts, but FAR air frame failures would up the challenge difficulty, and explosive potential.

I guess I could allow that.

Does FAR include any parts?

[Gordon Fecyk]

2 hours ago, TheTripleAce3 said:

Does FAR include any parts?

FAR introduces flap and spoiler settings for control surfaces, and it permits mass / strength adjustments for wing parts. It doesn't introduce any new parts.

It also models aerodynamic stress and will explode parts under too much of it, and models lift and drag for the whole craft and not just for wing parts. As Ferram4 puts it, "a fast enough brick will fly, if poorly."

Edited April 27, 2018 by Gordon Fecyk
Grammar

[TheTripleAce3]

5 minutes ago, Gordon Fecyk said:

FAR introduces flap and spoiler settings for control surfaces, and it permits mass / strength adjustments for wing parts. It doesn't introduce any new parts.

It also models aerodynamic stress and will explode parts under too much of it, and models lift and drag for the whole craft and not just for wing parts. As Ferram4 puts it, "a fast enough brick will fly, if poorly."

I'll add it tomorrow

[Klapaucius]

On 4/23/2018 at 4:33 AM, Stratzenblitz75 said:

Here's 2.032 km/s <1 Km. The real trick to doing this is a fairing + sideways heatsheild.

I didn't optimize this very much so someone could probably take the same principle and make faster one.

And yes, it does fly at lower speeds and can be landed without a parachute (although, with much difficulty).

Whoa, that is impressive. I got going at a pretty good clip (with a few different designs), but I could not get near where you did. Yes, heat control seems to be the key. At a certain point it just loses power.  This stubby, slightly Battlestar Galactica thing (in two variants) was my most successful:

 

Edited April 28, 2018 by Klapaucius

[TheTripleAce3]

@Klapaucius 1700m/s is impressive I will admit. Especially for a design as wide as that.