5/23/2008

Ready for Engine Test Runs (Props anyhow)

I know, I know... Props! Ugh you say... Yea, it seems just wrong to have props on this thing. But for now, they will hopefully test if the craft is flight worthy and help set the balance. I'm crazy to be doing this project, but not crazy enough to risk eight grand worth of jet engines on a test flight that might result in a big lawn dart maneuver from 200 feet. You'll see below the final assembly stage setting up for engine runs. Also, you'll see a rather cheesy fixed gear setup under the plane as well. Once again, no sense risking full retracts and gear doors, much less the time to build them, if the test flight lasts 12 seconds.

Engines are 2 SuperTiger 3000's, swinging 18 inch 3 bladed props.

Behind the engines are equipment trays that have the tanks and servos for the engines. If this works, all I have to do when I'm done with the prop test flights, is grind out the firewalls and unbolt this tray, and then bolt in the turbines...just about an evenings' worth of work.

I'm fairly sure of the balance point, but would not cast that in stone. What you see here is a 2nd equipment tray, that has a 2nd radio system on it. Jerry will man a 2nd radio for the first few test flight. This will run 2 main functions. First is 2 bomb drops that will be able to ditch a weight at either end of the plane. Enough to shift the balance point 1 inch forward or backward immediately. Second, is the pump you see here, and the tank (a second tank will be at the other end of the plane) These are 24 ounce tanks, and each will be set at half full. He will then be able to pump water from the front to the back, or the back to the front, as we need, in flight. This system works awesome on the bench. I can shift the balance in a range of 2.5 inches within 75 seconds. Another perspective, is that it can vary the weight on the nose wheel by 2.25 pounds, if that gives you a better picture of the range of control I have with it. I hope to get the balance nailed down in a couple test flights instead of what would normally take a couple dozen flights to get it right on the money.

Balance came out pretty good. For now it looks like it took just under 2 pounds of nose weight. Considering that on the finished bird, it will have a decked out cockpit, and this one had nothing done with it, that will work out well.

Two final shots showing the assembled bird.

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