mark, your absolutely right about your thoughts....but when you make the thrust duct to small, the air velocity increases, as the thrust decreases. ther is a combination between the fastest air duct velocity, and the maximum thrust in ducted fan models. i maintained max thrust on my pyranha, as it has half power hoover power and can be hand launched.....also it has good top speed "fast air velocity" so it can achieve 150mph top speed. randy.
Cool Randy do have a pic of that pyranda? and how did you figure it out how much to taper the port? Also are you saying that you can hover and edf at half throttle? Mark
mark, i have video of my pyranha posted on my YouTube page.....you can get a e-flux calculator...i made my thrust tube small, and kept makin it bigger til i was happy with it. not very scientific here, lmao. here is a fan calculator http://www.s4a.ch/eflight/fancalc_e.htm randy.
Man that is really a cool java program thanks Randy BTW Trish and I are going to try to cut out a pair of Eagles tonight on a live show and build them up to fly tomorrow! Mark
Maiden went pretty good after the winds died last night :roll: I found some changes that needed made and am in the process of cutting a new one out, man i really need that upgrade :evil: I had to move the EDF unit forward for CG issues and will re-maiden hopefully tonight if i can get it done in time. Power seemed decent, top speed could be better though. Attached files
Ok, I am pretty confident about the way this thing will fly now, I will post the files and once I work out the CG hopefully on Wednesday evening I will post best CG location. It is designed for 56mm fan unit (2.25 inches). I used a turnigy 4400kv motor with it. I also used a 1350 zippy 25C lipo, should be using at least an 1800 25C 3S pack. http://www.hobbycity.com/hobbycity/stor ... oduct=4198 Attached files F-22-EDF.rar (426.4 KB)Â
Jnida63, Glad to hear you got the parts Man this one came out cool looking bro! Are you thinking of doing a video for us guys to see it in action? Thanks for sharing this with everyone here Mark
Hopefully i can find a video cam to take some video, mine is broken and the 1.5 upgrade is more important than a video camera right now)