Roger's Sukhoi SU-26M

Manufacturer: Carl Goldberg
Type: Sukhoi SU26M
Engine: Supre Tigre 25cc
Wing span: 1.84m. 72.5"
Weight: 5.2 Kg
Aprox. building time 21 months.
Paint job (with slight differences)

This is the story of Roger's Sukhoi 26M. It took a while to finish it. For details, see Sukhoi building gallery. The plane's paintscheme is based of the Swedish Aerobatic team, Team Eagle. Do not let the big HP logo fool you. Both Roger and Ben just work there , HP did not sponsor the plane...
The first flight was in October 2001. Before, in September, some taxi test were conducted. In the rest of 2001, only some flights with the Sukhoi took place. Again some delay occurred, due to an engine out situation and the folowing landing that removed the gear from the plane.
As of March 2002, several succesful flying days logged at least 15 flights. One issue was solved during this time, the gear is changed to have the wheels stick out a bit before the CG, so it does not wants to tip over the nose while taxiing. Two other issues, the cowling (breaking by vibration) and the engine (needs some fine tuning) are to be solved soon. For photo's of the finished plane and the adventures during flying days, see the Sukhoi Flight gallery. Oh yeah, if you are wondering about the pilot, we named her Carly...

First flight report:

by Roger Wegert. October 2001

The Sukhoi his a great flyer. I had the first flight all by my self at the field in Almere, Holland, on a normal windy day. After some engine tests and adjustments I felt ready to go. I taxied all the way from the pits and put the nose into the wind, gave power slowly, and the engine started to stutter and I could not recover thrust, and the engine died. Rolled the plane back to the its thinking....why is she getting rich? I had the tank aprox. 30 cm from the carb, the tank on the CG, maybe this is to much? I had a small exhaust valve with me and installed it, run the engine again. Now better! Lets go...
I taxied back, against the wind, gave slowly full throttle and now the response was better, but still rich. I held the tail, cleared the carb of fuel and slowly got her to give full RPM. Take off! 15 meters! Nice but crisp control...this baby loves to fly! I got back to half throttle and trimmed...two "clicks" elevator and there she was. Perfectly stable. Sharp turns and a little bit of all and then landing. Set up for a "normal pattern", rather steep final and flare...landing this plane is a non event.
Very nice. 3 more flight that day, but still not like the engine performance.

Next flying day, I had my good friends on the field who wanted proof of my Sukhoi story, seeing is believing! Back in the air for some lovely aerobatics...what a plane! Great verticals! Looks very realistic in the air.
Now I just need to see how she stall too....climbed high, reduced the throttle to idle and kept the nose high...waited...right wing stall and in a nice spin she went. Two rotations and we pulled out, now adding throttle slowly, and here she stutters again, me now jerking the throttle to clear the carb of fuel, but no, she decided to "go silent mode". I initiated a landing pattern, nice altitude, no problem here, turn for base, still good but speed is getting on the low side of what I am used to, turn final and I realize I will not make the field.
Fortunately, our field has no obstacles, and only high grass surrounding the field. I made my flare in the high grass 5 meters form the edge of the field, came down a little hard. The damaged was a lost gear and belly pan and small scratches here and there. The famous weak spot of the CG Sukhoi. Need to fix the engine.....

I moved the tank forward, removed the exhaust pressure valve and ready for a new test at the field. There was never a problem starting the engine before, but this time my arm was on the verge of coming off. I tried several carb settings, but now success. Emailed Perry for tips and set up the plane in the garden without the cowling for engine tests. This seemed to be a great idée. Now I could adjust the engine properly and now she seems to be OK! Still not great in idle, but will test with a warmer glow plug. Mid range and full is perfect! Here is Perry Carbs tips:

"Rotate the idle disc a very small amount in the clockwise direction. The engine rpm will go up. Bring the idle back down with the small screw on the top of the carb. This should solve the problem."

Now I just have to wait for some good weather to fly again...I will keep you posted with more pics.

New flight report:

by Roger Wegert. 8th of April, 2002.

I rebuilt the elevator control, removed the large BB servo and installed two independent servos in the back. They show and I lost a little on the "scale" look, but decided that I put performance in the first place. Now I have not "flimsy" elevator and perfect response. I installed a spacer for the landing gear to have the weels in front of the leading edge, this to get rid of the tendency to nose dip while taxiing downwind at strong winds. Work great in both landing and take-off. I am NOT happy with the ABS cowling and belly pan. It does not withstand the vibrations and rip open. I had it removed and glassed the whole inside and now it is reasonable OK, but heavy. I suggest to get a new glass cowling and belly pan, and if you live in the Netherlands, get it here: Hobby-In. I got the engine working great after some fine tuning and I now rely on her fully, witch means I dare to put her through the paces. Vertical performance is fantastic and I am able to perform a torque roll, now its only up to me as a pilot to make it look good! She snaps like a devil, positive and negative. I had Hans, an experienced pilot, to have a go and he liked the performance and overall handling of the Sukhoi too. Next for me is to work out the knife-edge, moment-roll (4 point rolls). This plane does not permit "sloppy" flying, bad entry into the maneuver, and its hard to "clean up", just like is should! I can really recommend this great plane for any flyer who want to get a nice looking plane that can fly the whole program.

Sukhoi grounded:

17th of April, 2002.

On this Wednesday evening, during another really good flight, the engine quit in mid flight. What followed was a succesful landing and after investigating the engine a it turned out the pushing rod bearing had collapsed. More update after the engine is repaired.

Sukhoi maintanence:

by Roger Wegert. 26th of November, 2002.

In May of 2002, my Super Tiger 25cc engine decided to stop making the necessary noises, permanently. Coming out of a dive, throttling up, she just died (bearing meltdown). I was very happy with the performance of the engine, until then, and decided to try to find spare parts for a Super tiger, but no go. I vacuumed the internet, contacted dealers world wide etc. and all I got was confirmation that the factory had moved from Italy to China. Waiting all summer for parts out of China, I eventually decided to get me an identical engine, new from a flying buddy of mine who had one. Now I ordered a new fiber glass cowling from hobby-in here in Holland. Wow, that is quality instead of that ABS stuff. I am now installing this new cowling, a baffle plate for cooling and preparing to spray, this time adding a fuel resistant clear coat on top. She will now be back in the air by spring, new and improved! More to come....