AGM Design challenge

[ihtoit]

The trademark "Simple challenge" from me: build and demonstrate an airbreathing unmanned vessel that can hold level supersonic flight *without* the aid of afterburners or rockets at an altitude of 200-250m ASL.

Rules:

- Stock aero/atmo heating. I will not consider FAR entries nor will there be a separate table.

- Craft must use one stock airbreathing jet and no other means of propulsion.

- Craft must utilise separate control surfaces for roll, pitch and yaw (ie one wing, one tailplane and one rudder).

- no intake spamming. By this I mean absolutely no more than TWO intakes.

- no part clipping.

- Undercarriage may be ejected to save weight - particularly as you won't be needing it again.

- non-stock structural parts OK as long as they do not include "hidden" inline intakes. Precoolers are the sole exception to this rule as they serve a primary purpose other than as air intakes (although a precooler intake will count toward your intake total).

- Craft must demonstrate a range of at least 40km.

- Craft does not have to survive.

Scoring:

One screenshot of the craft at a distance of at least 40km from the KSC, in level flight at less than 250m ASL, showing maximum speed.

In the event of a tie for speed (measured to the nearest tenth from the navball), board position shall be decided by lower altitude.

Leaderboard:

1. ihtoit (see below): 1248.9m/s at 240m

2.

3.

4.

5.

Challenger's Entry: Whiplash-powered, one intake, 1248.9m/s at 240m. And enough fuel even at this altitude to make it to the next continent. Wings by Firespitter.

Edited July 21, 2015 by ihtoit

[Coga19000]

So, basically, you want the Kerbal version of a Tomahawk?

I do think I have some old designs on the shelf that I can make use of.

[ihtoit]

So, basically, you want the Kerbal version of a Tomahawk?

I do think I have some old designs on the shelf that I can make use of.

Yep, pretty much - although the Tomahawk doesn't supercruise. I want to see atmospheric heating!

Oh, reminds me, rules update - it's minor.

[Foxster]

Squeezed a bit more out of her...

Edited July 21, 2015 by Foxster

[t3hJimmer]

Here is my entry. All stock parts, but I used pilot assistant to help maintain the correct altitude.

[Darren9]

Can I skip the undercarriage and launch off a vertical clamp? Is procedural parts/wings acceptable?

[Foxster]

A little more (all stock BTW)...

Edited July 22, 2015 by Foxster

[Foxster]

I know no one is still following this one (including the OP) but I keep having ideas and, well, I've just had a bit of a breakthrough...

[t3hJimmer]

Damn! That's crazy fast!!

How are you dealing with the heat?

I know no one is still following this one (including the OP)

ikr, why make a leader board if you're not going to come back to the thread?

[Foxster]

Damn! That's crazy fast!!

How are you dealing with the heat?

ikr, why make a leader board if you're not going to come back to the thread?

It's a few things...Low drag parts, heat resistant parts, low part count, careful shaping of the fairing and use of some Radiator Panels, though they make a surprisingly modest contribution. Basically its a cruise missile..

A couple of tips for anyone else who fancies trying this:

Steering 114° from the end of the runway takes you to a gap between islands and so giving a longer run without hitting hills.

After 1250m/s increase speed very gradually, in 10m/s increments. Heat increases with acceleration but then settles down again.

Edited July 24, 2015 by Foxster

[Foxster]

Another few tweaks to improve the stability so it flies with 0° pitch and moving to just one 'wing' right at the front of the craft gained some speed...