[wingtipper]

Yes Wayne you Flew the Pulse well, Well Done.

I managed to get in about 4 Flights with the Gee Bee and even did a outside Knife edge upon Steve L Request which i manage first Time the second time i had dumb thumbs but recovered quickly without mishap.

Normal Knife Edges I'm was Use Too , So it was good to Try something Different, Thanks Steve L.

Steve

Love the Gee Bee


THE PIC WAS DECEIVING IN THIS POST . seeing this in the flesh over the weekend it was nice and scale like , a big plane indeed .

---

I test flew the Vipers on Friday. The weather was perfect being cool and still, tho’ the sky was a little grey there was no trouble with visibility. The red white and blue colour scheme turned out to be highly visible in the air.

I’d mixed a batch of 4:1 fuel, just methanol and caster as this is what they use in competition. The engines had been run in on this mix and both operated very reliably when they were bolted to the bench. I don’t think I’ve ever had a glow engine run as nicely as the two Thunder Tiger 46s I brought for these vipers.

When I read about how people set up their pylon models I found most would say that you want very slow rates to fly around a pylon course. You don’t want any twitchiness just a nice and smooth response and you want to be able to use the full throw of the sticks as well. For this reason a lot of people use dual rates, High rates for take off and landing and low speed flying and low rates for when the throttle is open wide and the plane is going fast.

It was with more than a little trepidation that I stood behind the first of the two vipers with high rates selected. We were on the Pylon course and taking off across the strip width ways, there’s only a fairly short distance with which to build speed and get airborne.
This was it, Ian was holding her by the tail with the engine running at about ½ throttle. Before I had a chance to wind it up to full peg he let her go. I pushed the throttle wide open as it had almost covered half the width of the strip. Magically she roared into the air and accelerated rapidly away.

Now Vipers don’t have very big control surfaces and they are set up with relatively small throws even when on high rates. Turnigy 9X Radios have very fine trims, so even several clicks on the Turnigy 9X’s trim buttons makes so little difference that you’d never notice it. The viper needed a little up trim, quite expectable as they are rigged with zero incidence and zero thrust angle. She also needed a little left aileron trim. After what seemed like a disconcerting eternity of clicking trims she finally flew straight and true. It wasn’t actually that she needed a lot of trim, it’s just that with this radio and how Vipers are set up it seemed like a lot of clicking to get there!!

I switched to low rates and let her run flat out around the sky for what seemed like half an hour, but in reality was only just over 2 minuets. The ailerons were a little soft on low rates for my liking so I later upped them from 50-70% the elevator was fine on low rates and was certainly able to turn her around quite smartly so I left that as it was.

One thing I was noticing is that a Viper flies nothing like a RareBear. By comparison Vipers are rock solid in the air, more predictable and track much better. They seem more slippery and carry their way much more than a RareBear as well.
Another thing is that they don’t seem to tire three quarters of the way through a flight like a RareBear when it’s Lipos start to get low. The Viper just Keeps on powering along regardless!! The Viper being a bigger plane is much easier to see but is not nearly as nimble a flier as a rerebear. With a Rarebear if you get it out of line you can put it back pretty quickly but with the viper it seems to take more time to make an adjustment and it felt like it often got to the next pylon before any correction could be completed. It will take a bit more getting used to but that’s the fun bit !!
The first landing was interesting, I backed off, slowed her up, turned and lined up with the strip, Vipers can slow up quite a bit and still fly. She just floated on down the strip with her engine ticking away at a fast idle. I’d set my idle speed a bit high and had to fly it onto the ground cause once she hit ground effect she wasn’t going to slow up any more. Luckily the strip was 200m long!! A bit of a bounce and she was down perfectly fine and all in one piece. I adjusted the idle down a bit lower and had no such trouble after that! The test flight of Viper number two was a bit less stressfull trimming was about the same but I’d already upped the aileron throws on low rates as I did for the Viper #1 and I remembered to set the Idle down to a nice low tick over before taking off.

Defiantly fun, fast, furious and rock solid machines! They fly a bit like a trainer except for the top speed. And the sound and smell of glow fuel thrown in certainly makes them something different.

Here's some video of Viper no1 in the air.

http://www.youtube.com/watch?v=cCxhlSvjS40

nice writeup JASON and great vid to boot . let us know if there are any differences between these 2 birds . they look very stble in the air , and remind me of long legged race cars with high diff ratios .