Nine Gallon Challenge -or- KD Pinto Challenge

[ihtoit]

Beast of a challenge!

You are provided with:

40 units of liquid fuel - no oxidizer, no other source of fuel

1 C7 Mk. 1 cockpit with 1 Kerbal

one stock C7 turbojet engine or one F119 Turbofan (B9 Aerospace required) - no other propulsive unit

one pair of active control surfaces of your choice from the PX - no more control surfaces than this

one pair of matching wings from the same parts mod as your control surfaces came from (ie if you use B9 control surfaces, you must use B9 wings) - no more wings than this

Two (stock) Kerlington Delta Deluxe winglets

ONE intake

Simple challenge: How far can you fly, given the above constraints?

Can you beat 282km, with a safe landing?

Edited January 26, 2015 by ihtoit

[hoioh]

ok, so I made it to 524km on 40 units of fuel. Used B9 wings, but a stock jet. I think I can do better though, I didn't fly below terminal velocity for the entire run, so I got to have another go at this.

For the moment though:

Javascript is disabled. View full album

[ihtoit]

nice! I went with my original design again and made it almost as far as those mountains in the North. A night landing meant I forgot to lower my landing gear, though, and instead of a perfect three-point touchdown in a small depression 384km from the runway, I made a perfect belly landing which then rolled and broke off a wing.

BTW I think the stock turbojet is the most efficient of the stock airbreathing engines, I put in the B9 turbofan as an alternative for the simple reason that it offers great pitch authority on small aircraft (handy for low speed takeoffs and short runs).

Edited January 26, 2015 by ihtoit

[hoioh]

ok, so I thought I could do better and so I did. I think I can make it out to over 900km with a better direction. I had to cut short because I was flying into the ocean if I didn't.

Javascript is disabled. View full album

896km by the way.

- - - Updated - - -

nice! I went with my original design again and made it almost as far as those mountains in the North. A night landing meant I forgot to lower my landing gear, though, and instead of a perfect three-point touchdown in a small depression 384km from the runway, I made a perfect belly landing which then rolled and broke off a wing.

BTW I think the stock turbojet is the most efficient of the stock airbreathing engines, I put in the B9 turbofan as an alternative for the simple reason that it offers great pitch authority on small aircraft (handy for low speed takeoffs and short runs).

If you have enough lift from your wings (I picked the wings with the most lift and the control surfaces with the most lift this last time, you don't need pitch authority. I limited the thrust to 40% on the engine, then went full speed 0/45/0 (after rotating the craft in the vicinity of the right direction. I never had to touch the throttle as it never went over terminal velocity. I jetted up to about 15K, then turned to 20 degrees AoA, then at 19K I dropped it to 10 degrees AoA. After that I just left, baked a bread and occasionally hit F5 whenever I passed the screen. 40 minutes in I had to change my direction 355 degrees because I ran out of land. I could've done better if I changed direction earlier. That way I wouldn't run out of land before reaching the north pole. Though I don't think I can get quite that far, not within the rules limitations anyway. Using more wing surface and maybe 1 or 2 extra intakes I could make it all the way out to the pole with just 40 fuel, simply by flying higher and faster.

[Groot]

I'll just leave this here, 3000 km.

[ihtoit]

interesting, but why do you have oxidizer space and why can't we see your aircraft design?

[hoioh]

Not to mention the lack of a safe landing. and 48K altitude with the one intake is never going to cut it. Maybe with 10 or 50 intakes, but not with the 1.

The oxydizer space can be explained from the use of a regular tank, it's slightly lighter.

[sdj64]

interesting, but why do you have oxidizer space and why can't we see your aircraft design?

Groot has oxidizer space because the 40 fuel-intake combo parts are super draggy compared to regular intakes. It is kind of strange that Jeb gets killed at 00:00:00 though. But drag minimization is really the key here. In stock atmosphere that means flying as high as possible, using ram intakes (most intake area per unit drag), and lowering the weight. Only one intake, as per the rules. If I'm reading between the lines correctly, the cockpit is mandatory but the wings are optional? I didn't use the maximum number of wings. Only the two delta winglets and one small control surface.

Here's my entry. 8294 km.

First picture is on the runway after bleeding off fuel. I had to bleed off 0.5 units of fuel since the closest the tweakable gets is 40.5. All stock parts with Ven's stock revamp (a texture pack).

[Groot]

It was just a proof of concept, and I didn't even expect it to be competitive to people who know how things work. I knew you could circumnavigate with turbojet because it's just super OP.

The way to go is maximum orbital travel, and not lift and glide.

Edited January 27, 2015 by Groot

[Batz_10K]

You might like to update the rules a little.

It's entirely possible to make orbit with such a small jet that meets the current rules and a little Kerbal ingenuity.... then you can go as far as you like

...Actually, it *does* help if you get out and push...

I think jetpack thruster fuel refills should probably take away capsule monoprop as well...

[hoioh]

That in itself is an achievent! Well done Batz!

[ihtoit]

actually, it's not. Interesting cheat into orbit for the "infinite distance" award, but you did use EVA thrust - which is against the rule of the jet engine being the only allowed means of propulsion. Also, the use of EVA fuel violates the liquid fuel only limitation.

[Pds314]

Slight factual error on the title. You call it the "Nine Gallon Challenge" and yet you give us 200 kg of fuel. One unit isn't one liter. It is 5 kg, or, in the case of an orange tank, which we know to be 8/9ths fuel by weight, or about 1.6 gallons.

Overall, a more factually correct title would be something like "65-gallon challenge."