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Cheetah light sport aircraft pilot report.

I had the opportunity to meet and interview Vladimir Chechin designer of the Cheetah XLS while covering Airventure for Lightsport and Ultralight Flying magazine. As I interviewed him on the Cheetah XLS lightsport aircraft I could see that he was a very grass roots down to earth individual. Vladimir had started out flying Rogallo style hang gliders in a group environment. Here he learned very quickly, that when a whole group of people are flying the plane you are planning on flying, it had better be easy to pre-flight with everything out in the open and easily accessible! When you build something for a group environment you need to build it tough and that you need to build it to be easy to repair!

So when he got together over 16 years ago with a friend of his Mike Blythe, who has been building weight shift trike aircraft since the early 90's, to design and manufacture the Cheetah XLS he started to design it with those thoughts in mind. One of the true tests of any design is whether or not it has been used successfully in a training environment! In a training environment you get more cycles on parts and pieces in a week than most pilots will put on their craft in a year! So I was very impressed to learn that a Cheetah XLS with over 1,100 hours on it in a training environment was recently sold to a private individual who is using it for recreational flying!

Over the years I have seen the Cheetah XLS at a number of airshows, so this year I gave them a call to see if they were interested in having a flight report done on it during the Midwest LSA Show held at the Mt. Vernon Airport in Mt. Vernon Illinois. Jon Syvertson one of three brothers that own Midwest Sport Aviation replied that they would be more than happy to provide a plane for me to fly during the show.

I arranged with Jon to go flying first thing in the morning but the weather wouldn't co-operate until mid morning. A nice thing about the Cheetah XLS is that it is very easy to pre-flight. All of the control systems and linkages are clearly visible, or can be accessed via zippers. Because the Jabiru 2200 engine is air-cooled, you don't have to worry about coolant levels, or loose hose clamps. The engine compartment is easily accessed by removing covers located on each side of the engine compartment.

One of the first things a conventional pilot will notice is that the nuts and bolts used on the Cheetah XLS are not AN grade. They are however AN grade equivalent in strength. The reason for this is that manufacturers outside of the U.S. do not build with AN grade bolts. All of the nuts and bolts on the Cheetah used for this flight were color marked, so that if anything had moved from spec, the pilot can see it immediately during a pre-flight.

At 5' 6" and 200 lbs I had no problem getting into the Cheetah XLS, but did require an additional seat cushion behind me to bring me forward enough to operate the rudder pedals comfortably. The pilot restraining system consists of two shoulder straps and a lap belt. These were easy to get into and release. One of the things I noticed right away once secured in the plane was that the visibility over the hood, even sitting on the ground was exceptional. I had expected with the style of cowl used to find my view forward blocked.

Jon climbed into the pilot side of the plane, while I can fly from either side, my preference is to fly from the instructor's seat. Jon buckled himself in and connected up the intercom. We then closed and secured the doors. Both Jon and I are in the 200 lbs range more or less, we were quite comfortable in the cabin, with lots of room between us and above us. Once in and secured we dropped our outer arm rests down to give us access to the dual throttle system.

Jon then gave me a quick run down on the operating speeds, temperatures and start up procedure. With the fuel switch on, the throttle at an idle, choke activated, ignition switches on, Jon checked the area, once he knew it was clear he hit the starter and within three or four revolutions the engine fired up, and the oil pressure gauge came to life. With brakes applied, after a short run at 1200 rpm he brought the engine up to 2000 rpm, to bring the oil temperature up, and then checked the ignition.

I was expecting a noticeable difference during the mag check like I usually have on a Rotax 912, but I don't think the engine dropped more than 50 or 60 rpm. With everything working correctly and temperatures ready to go flying we started taxiing out to the runway. At this point I asked Jon to give me control so I could check on the ground handling and ease of manoeuvring. There were several rows of planes in the tie down area and I was able to easily turn in and around them without any problem. One thing I did notice though was that the brakes really only put a little drag on the wheels, they could not be relied on to stop the plane if it was moving forward at any rate of speed.
Please see Editors Note:

Turning control back over to Jon he proceeded down the side taxiway, to the end of the runway and prepared for departure. One of the things about the Cheetah XLS that stood out during this process was that the visibility over the nose, out the side doors and through the skylight is exceptional. Jon ran me through the take off procedure, applying flaps, throttle settings, etc. and once given clearance from the tower he applied power and started down the runway.

We were fighting a fairly stiff 90 degree gusty 10 to 15 mph crosswind, but plane and pilot handled it without any problem. After about 50 feet you could feel the nose wheel lift, and about 150 feet we were airborne and climbing out. I have to say I was impressed because previous experiences with the 85 HP Jabiru had left me with the feeling that it was a little under powered for this large of an aircraft. Not so the Jabiru 2200 is a perfect fit for the Cheetah XLS, even with two hefty pilots and about 3/4 of a tank of fuel.

We climbed out to the end of the nearly 6500 foot runway and then released the flaps. We then headed towards a body of water south of the airport. In a steady climb at 80 mph the Cheetah was showing between 650 and 700 feet per minute climb rate. We then levelled the plane out and set up the engine at cruise rpm. 2900 rpm gave us an initial cruise of about 80 mph, after about a minute or so this increased to 85. Jon said that the increase in speed is because the plane "unloads" in flight after a couple of minutes flying. Removing my headsets to listen to the engine noise, I found it to be louder than I expected, not that the cabin noise was loud it was just louder than I am use to.

Editors Note: The Cheetah Factory reports that the Cheetah XLS at 2600 rpm will cruise in the75 to 80 mph range, at 3000 rpm speed comes in at just under 100 mph, 3300 rpm will give you about 110 mph.

At this time I checked all of the engine gauges for temperatures, and pressures. Everything was located right where the manufacturers recommendations said they should be. I have to point out that many of the aircraft that I have flown to date, especially when equipped with the Rotax 912 series are usually being flown at temperatures and rpm settings that are nowhere near that recommended by Rotax! It appears the Cheetah factory has listened to the Jabiru engine factory and developed an engine mounting and cooling package that matches the engine requirements to a T. There was no vibration in the control system or through the floor boards that I noticed from the engine and prop combination, another thing that would indicate the aircraft manufacturer and engine manufacturer have worked together.

The Cheetah XLS has a trim tab on the elevator, once in straight and level flight you simply trim it forward for more down attitude or back for up. The pressures on the rudder pedal and ailerons are very light, and the controls when activated give immediate response and feedback. Both Jon and I did a number of turns and I did not feel any sense of adverse yaw, something you normally experience in this style of aircraft.

One of the stability tests I use for a plane is to put it in straight and level trimmed flight, then suddenly push the stick forward and release it.  Experience has shown that the plane should porpoise three or four times and then continue on in straight and level flight.
The Cheetah did just that, but in only two cycles.
You then do the same thing only pulling the stick back and then releasing it. In both cases the plane only porpoised twice before stabilizing itself. It had no tendency to continue porpoising or to continue on into a dive or stall.

Another test of stability is to do a 360 degree turn first using only the rudder, with no ailerons, and then ailerons with no rudder. Again the Cheetah passed with flying colours! You can actually do a very coordinated turn using just aileron or rudders. This means that in the event of a control system failure the plane can actually be flown and landed using the remaining control system. Something that I have had to do twice in my career!

One thing I did notice during this exercise though was that the top rear part of my door had a tendency to open and stay open a little bit during the turn. No problem during straight and level flight or climbing, just during a turn.

Next on the list is stall at altitude with and without power. Because of the low ceiling height I asked Jon to climb to cloud base which was about 2,000 and perform one of each for me.  At an idle with the stick right back as far as he could get it the plane just waddled in the air, I could feel Jon dance along with it on the rudder pedals! No matter what he did with the engine at an idle the plane would just waddle around refusing to drop it's nose, once I think it might have dropped 20 or 30 feet in some turbulence, but that was it!

So now the full power stall, Jon set up at a safe altitude, with full power he started coming back on the stick, again it was right back in his stomach, the plane hung on the prop for a second or two and then the nose dropped. We dropped about 100 feet from a full power full stall attitude, Jon released pressure on the stick and we were flying again.

I then asked Jon to fly back to Mt. Vernon and demonstrate a circuit with a touch and go. We entered the circuit on downwind at about 85 mph. slowed on base to about 70, turned to final and applied flaps. Jon then brought the engine rpm down to about 1700 and came in under power until he crossed the numbers. Reduced power in ground effect, reduced power again, applied a little back pressure on the stick, about 200 feet later the mains touched. He used the throttle to keep the nose up a little while travelling down the runway on the main gear. Then applied power and started climbing out.

As we reached the end of the runway I took over control, reached up released the flaps and started a climb out to enter the circuit. One of the first things I noticed was that it is a little awkward especially in turbulence, to reach up and release or deploy the flaps. To do it you have to let go of the stick, or let go of the throttle and awkwardly reach over your body to reach the flap handle.

I have now enter the down wind leg of the circuit. Since I am an old ultralight pilot, I like coming in with lots of altitude, that way if the engine quits I can still make the runway. Also it gives me experience side slipping, and judging altitude. So on final I was probably twice as high as I should have been! No problem, the Cheetah XLS side slips, and forward slips with no problem at all. Feeding rudder and aileron  in I had no problem keeping the plane's center line on the runway, despite the nose pointing over 45 degrees away from it.

At about 50 feet I straightened her out, remember that 10 to 15 mph 90 degree crosswind! It was now up to about 20 and really gusting! Still no problem for the Cheetah. There was only one problem, the dumb pilot, so use to flying on a Rotax 912 with an idle of 2,000 rpm I didn't realize that I wasn't at an idle, I was 200 rpm above idle and the poor old girl, with flaps on was just floating down the runway in ground effect refusing to touch down! With power back we touched down, applied the non existent brakes, good thing the runway is 6590 feet long, and headed back to the tie down area.

With flaps and an experience pilot I honestly believe you could get this little girl down and turned around easily into a 200 foot strip, not that I would recommend it for a daily chore!

Overall I give the Cheetah XLS, powered by the Jabiru 2200 engine an 8.5 out of 10. It gives a lot of bang for the buck! Has a proven track record over more than a decade of flying. It has a well established manufacturer, who has spent a great deal of time to refine it to where it is today. The U.S. distributor is currently in the process of setting up a dealership network, and already has sales outlets in several parts of the U.S. and in Canada.

The factory indicates they are in the process of updating the brakes system. I don't know what they can do about the flap location so that a pilot does not have to release the control stick to deploy them. The door tip opening I believe is just a matter of using stiffer tubing, or a latch system. My information is that a folding wing will be available early next year, and that the gross weight for the plane will be increased at that time. For those interested in floats the factory says they have not had a request for a float equipped Cheetah XLS yet but that they are working with a local manufacturer to supply floats and float mounting hardware. The Cheetah XLS is also set up to accommodate a BRS parachute system.

The plane basically fits into any category you want. You can build it as an experimental amateur built, or as an ELSA or pick it up ready to fly from Midwest Sport Aviation.

Aerial photography - Digital aerial photography - over 40 years experience!