raydar

Well got a break with the weather and flew this profile YAK today. First flight was made with 8 oz strapped to the nose as there is no official COG supplied with this plane. After a few feet she was in the air and a couple of clicks on the ailerons and elevator she was flying true, a very easy maiden. Found with the large control surfaces that she was very sensitive on the ailerons even with 60% expo but nothing I could not handle. Flew her inverted to check COG and she headed for the ground, decided to land and remove the 8 oz up front.

Second flight found that she flew straight and true with no weight added to the model at all, just like the sbach did, perfect. Tried to stall her 100 ft up into a 10 mph wind, I throttled back and with the slightest of up elevator watched her sit perfectly in the sky, did not drop a wing at all, just sat there not going forward or back. Infact im sure she started to climb in this horozontal position!. had a few low flybys and found her to be very stable at walking pace into the wind, far more stable than the sbach with no sign of wingrock at all, this was the experience I was hoping for with the sbach but it did not deliver. The Yak is much happier at stall speeds and does not threaten to torque roll the same when you add sharp power.

Third flight I had a dead stick above the middle of the runway with the dle 20 at 50 feet in ahover position, was no problem gliding her in.
Tweeked the engine.

Forth flight she deadsticked again 70 feet above runway, miss judged the landing and realised I was going to run out of runway and end up in the trees, forced her down and it was not pretty, totally thought I had damaged the fuse but found I had only flattened the landing gear, was suprised the model took the hard landing, think I was very lucky that it did to be honest. Spent a long time tuning the dle 20 before next flight.

Fifth flight she sounded great in the air, good transition, no gurgle and then deadstick? Landing was easy. Decided to call it a day after 3 deadsticks while the plane was still in one piece.

Not sure what is going on with the dle, not new to gas but struggling to get her to run reliable, can tune her rich on the bottom so she wont deadstick but it means she fourstrokes at idle and gurgles and chokes up below half throttle, no use to me with a model as light as this as cannot hover with a chocked up motor that suddenly clears and goes vertical like a bat out of hell. Tweek her for max rpm and thin the bottom end for good transition she seems fine but then without warning quits?. Got a few things to check out and if all fails im sure I have a walbro 793 lying about somewhere that I can try.

Anyway to sum it all up I would say im very happy with the way she flew, at 7 pounds 9 oz dry she has a wing loading of about 17 oz/foot and flys really well, a very good wing loading for a 3d arf/dle 20 combo, maybe not as good or strong as a kit built profile but for a plane you can throw together in a few days she is great fun. I will post a picture of her at the field and a couple showing the motor mount position and glassing and tri stock I added that I think is still required to handle the dle vibs. The picture makes her look quite small but it is a illusion as she is longer than the sbach and hasa much wider wing, it is only slightly smaller thanmy 30cc pilot yak.