So we (I often write "we" because we did this job together with another two newbies - Dima, my companion in this venture, and Granny, who makes almost all the things which need to be perfect with filing, cutting etc) were now ready for testruns.
First start-ups didn't bring any surprises. We've got 175 kgs of static trust in hot day and 170 RRPM on the prerotator - from the first attempt. Both thrust and RRPM were lower than I expected so we are now looking for more. But they were enough for test flight.
Sure, we spent some days rolling up'n'down the small runway, cheking the landing gears, looking for engine temperatures etc.
First I supposed to install the radiator over the engine - it would be better regarding CG and it was better due to hot coolant is going up as well as it is tending down when cooled. This way the radiator installed over the engine should take less power on the pump. But in this case it would take more efforts to install it so finally I've installed the radiator under engine. To make the prop as clear as possible the raditor doesn't stand vertically though I still have to check if this position is enough to cool it when flying hard in a hot day. This way as shown it work well at +20 deg. C.
Note that radiator's front edge is
slightly higher than the tail boom line - it was altered after we've found out that the
airflow isn't sufficient. It's OK now.
First sad thing was that the front leg refused to drive the grass strip - it has become bent after first rolls. Actually I expected this and we've built another stronger one which serves well even on the rough field.
