The Vyper Strikes, Part II

In the first installment of this report, we went over the equipment and set up of our new Vyper. We also explained why this plane will run 3s power instead of our customary 4s.

You can find that here:     The Vyper Strikes


This is my favorite kind of report because it's all about the flying. The new Vyper completely surprised me, because with a more moderate power system it is such an incredibly gentle and sweet flying plane. We had seen this before when we set up my friend Steve's 3s Vyper for sport, but I think I was expecting the plane to be harder to fly with a full 3D set up, and it really wasn't.

FLYING

Things that are all things to all people generally aren't. Of course, being a Scott Stoops' design, I knew the Vyper would be fabulous, but I was a bit skeptical that the plane would do everything well. Even the best designed airframes will sacrifice performance in one area to gain it in another. Nothing is perfect, but the Vyper certainly surprised me.

Most first day out with a brand new type of plane is spent tweeking mixes, adjusting CG and such...basic trimming stuff...but I just started having fun with the Vyper right away. I remembered the mixes from my first one and they worked perfectly on the new plane. With one notch of up trim she was trimmed. Later I moved the battery back and got the CG right where I wanted it, and had to take the trim back out. So this is basically a perfectly straight airframe. They all take a little something to get them right, but not this one.

At first it was hard to believe with the heavilly swept wing that a high pitch rotation wouldn't snap the plane, but I kept pushing harder and harder until there was no doubt the Vyper is very solid here. Generally pattern planes get all wobbly when you snatch the stick full back, so it was a little hard to believe you can do a beautiful point roll on one pass, and a vicious wall on the next, but with the Vyper you can.

Having flown dozens and dozens of pattern planes over the years I know they are superbly stable as long as you fly them the right way. It's when you get really careless and sloppy that you run into some of their quirks. Even the Aspera isn't perfect in this respect. Once I forgot what I was doing and tried a wall with my Aspera, and let's just say that it "surprised" me.

The Vyper has absolutely no bad habits. It does get a bit wobbly if you try an elevator on low rates. You simply don't have the control authority to pitch it past an unstable non-flying condition and into alpha. It's not uncontrollable or anything, but it does warn you that it doesn't like it. Simply flipping to high rates makes it all go completely away. On high rates the Vyper elevators almost about as well as the SHP. Maybe it will do it better as I learn more about what the plane likes, but for now it is still way more than good enough.

The Vyper's overwhelming strongest suit is it's knife edge (KE) ability. Right away I was doing slow rolls that stretched from one end of the field to the other, and it could have kept going too, except for our airspace limitations. Point rolls and KE circles were just as pretty, and easy too. Even with reduced 3s power, the Vyper does beautiful KE loops.

The Vyper has so much rudder authority you don't do much more that put a little pressure on it to hold the plane in a KE, and the first few slow rolls pitched up pretty hard because I wasn't used to this and over controlled it. Once I figured that out, slow and point rolls were as straight as if they were on a string.

Also benefiting from this amazingly powerful rudder are stall turns. I like to keep just a little throttle on, and when you hit the rudder the Vyper does a 180 and heads straight back down nearly through the same air turbulence it created on the way up. The plane does stall turns as well as a dedicated pattern ship like the Aspera.

Flat spins with the Vyper as very smooth and controllable. When you let off the sticks she stops right where you tell her to. It's very easy to do a three (or more) turn spin and have it come out pointed in exactly the direction you want it to.

Outside snaps are very clean and controllable. Inside snaps are just as crisp on low rates, but on high there is so much throw that the contols act like parachutes, and most 3D planes will wobble though instead of snaping cleanly. You can put in the right amount of throw with your thumbs, or you can flip to low rate. I use low, but I need to learn how to snap the Vyper on high rates with finesse. The Vyper still does better inside snaps than the rest of my 3D planes.

Pitch authority is really good, but it won't rotate nearly as hard as a Velox or Edge. It's more like an SHP this way. It will rotate respectfully but not violently. Of course, the Vyper is a 3D precision hybrid, so that long tail movement it is going to make it give up some pitch authority in exchange for pitch stability and smoothness. We're doing to dial up the elevator throw to 55 degrees next time out and I am sure that will help.

It was definitely surprising to see how fast the tail blows over the nose in a KE spin. With it's pitch stability I was not expecting this, but the Vyper does a beautiful KE spin that goes round as fast something like a 57" Extra SC, which is pretty good.

So far I haven't put any differential in my ailerons because it doesn't seem to need any. Whatever type of roll, or sequence of rolls, I want to do, the Viper does them very axially.

The Vyper, did however, really surprise me in one respect. I generally don't use my low rates because my program moves from one maneuver to the next so quickly. I simply don't have the time to flip the switch because I am too busy setting up the next maneuver. This means if I want to crank off a slow or point rolls, or even fly around fast, I just have to live with the plane being jumpy from all that throw and fly around it. Either that or I do all my precision in a straight sequence, and then flip to high and fly 3D.

With the Vyper I leave it on high rates and move from precision to 3D and back, over and over in one smooth sequence. The plane is so smooth at high speeds and high rates that it really isn't much different from a dedicated pattern plane. In fact, I think I'm getting to where I can fly better pattern with the Vyper than even the Aspera.

The only time I used low rates was when I wanted to do three perfect consecutive rolls in five seconds, like we did in the old AMA style pattern. I've got my low rate set up to roll that speed with the stick laid over, and I use little jabs of up and down elevator to keep it level. That is the only time I use low rate at all.

The Vyper hovers very nicely because all that rudder authority means you don't move that stick very much. With the bigger 13/6.5 prop, torque is very nearly overcoming the ailerons, and I'll be more comfortable once I crank in a little more throw. I can get that quite easily by turning up the end points a little.

Harrier is the one place the Vyper won't quite keep up with a dedicated 3D machine like the Edge 540. The Vyper probably harriers as well as many dedicated 3D planes from other manufacturers, but Scott Stoops' pure 3D planes, like again, the Edge 540, are so effortless in this respect that it is almost like cheating. Perhaps the Edge just has me spoiled.

The Vyper still harriers reasonably enough, though, and I was comfortable doing it on the deck right away. It was just a little sloppy, but it's probably my bad technique. There is nothing wrong with the harriers in the videos of Ben, Scott and KM flying the Vyper. I'm going to work on harrier pretty hard with this plane. It is the only area where it's taking a little extra effort to master, but any challenge that addresses a weakness in your flying is a good one to take on.

Finally, I don't believe I have ever owned a plane that lands as beautifully as the Vyper, even in 3D trim, with rearward CG, and on high rates. You just simply fly it in like it is any other sport plane and she will almost set herself down. The first few times she will sail right by you because you just about have to stop her dead in her tracks for her to flair out. The Vyper lands at an extremely low speed, with full control until she rolls to a stop.  My landings are generally sloppy because after 6 minutes of intense 3D, I'm so wrung out that don't care, but with the Vyper all you have to do is pay attention and the landings are almost always picture perfect.

Overall, the first, and lasting impression I get from the Vyper is it's sublime smoothness and precision, with an easy, forgiving nature. I'de say it is even smoother to fly than the Aspera. I know that is pretty hard to believe, but check the videos.

Finally, lots of electrics don't do so well in the wind. Electrics, especially 3D types, are generaly lightweight, and unstable air can toss them around pretty badly. Of all the 47" class planes, I have owned, the Vyper is the best in the wind. The vyper is my favorite plane for windy days because it just cuts through it like it's not there. Obviously there will be times it is too much wind for the Vyper, but not often. In the last video below, we're flying in 15mph winds with gusts to 25mph. You can see the Vyper get knocked around in a hover, but the rest of the time you can see the conditions hardly affect it.

NAIL

Where to start, eh? It is not easy to sum it up in a few words when you are talking about a plane that will fly beautiful precision sequences, and then with the flip of a switch go right into wild 3D, but the Vyper does it, and extremely well too.

I don't need one plane to fly precision and another to fly 3D. I don't even need to use my rates. I just fly the Vyper and it excells at both, just by being what it is. Since the Vyper can be almost anything I want it to be, I am sure it will become my new go-to plane.

Being so different, it took a little time to discover what the Vyper likes, and how to get the most out of both it and myself, but now it is coming pretty quickly. I can see that whatever I want to do, the Vyper is extremely capable all the way around.

My thoughts on the Vyper have changed rapidly every time I have flown it. Initially I figured it wouldn't do precision as well as a dedicated precision plane like the Aspera, nor do 3D as well as the full blown 3D Edge 540. Things that are all things to all people generally aren't.

But that was before the Vyper.