The HyperJet Speed Challenge

[waterlubber]

I was bored, so I thought that it would be cool if I could make a fast jet.

I thought to make a challenge.

Here are the rules:

1. Must be a plane. No spaceplanes, etc. You are not allowed to carry Oxidizer or RCS thrusters. (If you accidentally left monoprop in your capsule, we still love you)
   
2. No suborbital hops. For the ENTIRE journey, you Apogee must remain below 65km. No exceptions.
   
3. No dropping from orbit. You must use the exact craft from launch to landing.
   
4. No airhogging. Maximum 2 intakes allowed per jet, OR 1 ram/shock intake per jet.
   

Scoring:

Your score is:

Top Speed over Land - (10 points for every meter above 65000 + Every unit of oxidizer*2 + 150 points for every intake over the limit)

Leaderboards:

waterlubber: 1684.7 m/s, 1684.7 score

[waterlubber]

My entry:

Max speed 1684.7, I forgot to get a screenshot of the flight log BUT I did get one where I was clearly on ascent, and it was fast, too:

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[Voculus]

Will there be a separate category for FAR?

[Wanderfound]

Hmmmn...

Okay: this is a pre-existing entry to start with. If you're running a FAR/DRE leaderboard, I'll put together a single-intake version and see what I can do from a max-altitude dive. But, to set a baseline:

Just a quick little something I threw together.

Up.

Supersonic in the vertical climb.

Time to level off.

Getting warm.

And finally into the hypersonic.

Top speed during the climb.

That's the top, time for a bounce.

Negligible thrust at this speed, the air is going through the intakes too fast for the turbojet to handle.

Getting some speed up...

Note the speeds in the previous two pics: the first is 1794.4m/s and Mach 5.67, while the second is 1792.0m/s and Mach 5.69. The first is faster in m/s, the second is faster in Mach. This is because Mach varies with altitude, while m/s does not. Which gives me an idea...

Speed in m/s peaks here, at 1787.9m/s.

Getting a bit on the toasty side.

Peak mach, 5.77. Oops.

This might hurt.

Nup, all good.

So: 1794.4m/s or Mach 5.77, your choice, albeit disqualified by the double intake.

[davidparks21]

Just saw this challenge today, after spending a ton of effort learning how to eject a medium-heavy refueling craft on dual jet engines for (this) challenge, I thought I could apply the same design approach to a smaller, high speed jet. And Indeed it seems to work.

I present a dual jet, delta wing design utilizing 4 radial intakes (2 per jet). Top speed over land (measured by F3 menu): 2,270 m/s

Top altitude attained under jet power: 36,711m

No penalties, never passed about 40,000m (though had a high apoapis of nearly 150,000m at the peak), all stock other than flight engineer.

Notable challenges for this design:

- Imbalanced thrust: Stacking the jets allows the wings to provide stabilization, the two SAS modules go a long way to smoothing out the inevitable bumps and burnouts too.

- As you climb above 30,000m one jet will always end up being "dominate", producing more thrust than the other, as the other goes into burnout you counter it by dropping the thrust limiter on the dominant jet. Thus you can obtain thrust from both jets even at high altitudes.

I particularly enjoyed pulling the high speed descent maneuver at the end when I overshot KSC accidentally.

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Edited November 13, 2014 by davidparks21

[Wanderfound]

Okay: your standard basic FAR/DRE speedster.

Self-launching.

Good climber.

Level off.

...and that's maxed-out for level flight. 1,777m/s over land.

Let's try a dive.

Nope, no better. Lost too much speed from drag.

Try a more gentle slope. Better airspeed, but only a single m/s improvement over land. 1,778m.

Can't be bothered landing. Let's see what it can take in heat and pressure...

Who needs a tailfin anyway.

430kPa, not bad. Apparently DRE proof as well.

Not a good idea to touch the controls at this pressure, however.

1,778m/s over land, no penalties.

Craft file at https://www.dropbox.com/s/glgupx19kl0i82b/KSV%20Woomera.craft?dl=0

Edited November 14, 2014 by Wanderfound

[numerobis]

- As you climb above 30,000m one jet will always end up being "dominate", producing more thrust than the other, as the other goes into burnout you counter it by dropping the thrust limiter on the dominant jet. Thus you can obtain thrust from both jets even at high altitudes.

Delete the intakes and jets. Add two intakes, then one jet. Add two more intakes, and the other jet. That way, each jet will get exactly the same amount of air, no need to play around.

[Zipmafia]

Ummm....

I guess this challenge is kinda different, the rules surely are.

Very similar to these though.

Machingbird challenge

Fastest Jet in KSP

I'm going to try again to see if I can get faster, but check this out!

[davidparks21]

Delete the intakes and jets. Add two intakes, then one jet. Add two more intakes, and the other jet. That way, each jet will get exactly the same amount of air, no need to play around.

Really? oh, I've *got* to try this out!!

[Wanderfound]

Really? oh, I've *got* to try this out!!

Careful weight balancing (RCS Build Aid is very helpful here) is also worth the time. Get it right and you can fly smoothly on either engine: