Quote:UPDATE: Well, thanks to Cortana of CGI not only do we have the modelling time needed to get the control software working properly, we also have a name for the RF-047. It shall be named the RF-047 Kulbit.________________________________
We're also far enough along up that we can try and get to a stretch goal. After a little bit of discussion amongst ourselves, we've decided to use whatever extra money we get towards a proper retrofit of XR-71 into a proper propulsion testbed.
One of the biggest challenges we faced was getting the data we needed to model. Both the drives, and the spaceframe. We needed data on both, and test-flying the prototype made it impossible to seperate out spaceframe and engine characteristics since they were both so heavily entwined.
XR was the solution. XR is a standard 2A Blackbird spaceframe, modified with a second propulsion module mounted between both nacelles. Since the flight characteristics of the Blackird spaceframe were well known and documented, we could determine what issues were being caused by the engines and what were being caused by the spaceframe alone.
This allowed us to discover a throttle response issue that meant the engine output power lagged behind the throttle setting. The software expected a much faster response, so opened the throttles further when engine power didn't increase. When it did kick in, the computer was getting twice the power it expected, registered the overshoot and immediately shut the throttles. Then the cycle began again. It couldn't settle down to an even throttle setting.
In XR, with thrust vectoring enabled, it caused the spaceframe to porpoise to the point where it buckled hard enough to shed structural plating. But iXR gave us the hard data that let us determine what were engine problems, and once we can seperate those engine issues out and clear them up, we can determine the spaceframe characteristics and clean those up.
It's no bullshit to say having XR probably saved us a year of work. Hands down. She gave us the data. She probably saved us far more money than she cost already.
Our Stretch Goal therefore is to refit the main engines on XR, fit her with a full second cockpit and proper data logging equipment in the aft cabin. A dedicated development mule is something a lot of the big spacecraft developers have to hand, but it's a something that isn't normally available to us small-scale 'garage' builders. We got a little lucky, because we had space to park her.
When she's finished, we'll make her available to the any craft builder who wants to test their engines, or control systems with a standardised spaceframe with known and stable flight characteristics. Basically, we're going to make her a mule for hire, a testbed open to everyone for a fair price with full datalogging in the standard DCAMS format.
It'll put these tools within reach of other builders like us. It'll save money. It'll speed up research and development. It'll speed up competition. It'll mean some of the cool stuff coming from the smaller garages I hear about every month that would otherwise slip away into the background might actually get finished.
We're also adding a new Tier-7 goal.
A single day's utilisation of the finished XR. Along with time to fit your engines and get your data from the onboard hardware.
Or just come out here fly around and have fun with us.
Secondly:
Some people have mentioned it. If you want an combat-ready Kulbit. Don't ask us. We'll never build a full combat version. That's our promise to those who feel uncomfortable about funding 'warplane' projects. The Kulbit is a racecraft alone.
If you really want a combat-ready Kulbit, you'll have to do it yourself. You might even be able to sell a kit to do make the conversion.
-Thanks for everything
Jet, Mackie, Daryl
--m(^0^)m-- Wot, no sig?