Attached are a few photos of the Cougar assembly - I worked a bit on the ducting.
The plane has a cover over the cheater hole but the mold of the wing is the same as the older versions which means that there are all kind of angles and pockets just in front of the EDF inlet.
I ended up opening and sanding that area, also covered the landing gear wells in the wing.
The two halves of the fuse are not completely aligned and there is a ridge in the exhaust that I am not sure how I can sand as there is not too much room to reach inside.
I did make an exhaust duct but the outlet is currently 68% FSA :-\ I will try to open it a bit more and see if I can squeeze it in.
The wing mounts with 3 ugly screws which I should somehow cover (will try add a photo in the evening).
- The main question will be ESC cooling - The only place I found is under the battery inside the front landing gear bay. The two options are either drill some holes in the plastic bay cover from the bottom of the plane or just cut a large opening and push the heat sink out of the bottom part of the plane.
I think the second option will be preferred as the ESC gets quite hot at full throttle even if it is rated higher than the current drawn by the EDF.
Looks great Bobby!
I also extended the motor wires and placed the ESC next to the battery in the front. This area is quite large and with an air intake located where the nose gear retract would mount, you should get enough cooling.
With the fan you're using, I would also recommend creating additional intakes in the form of Naca ducts as shown here:
(http://i166.photobucket.com/albums/u98/maniac_316/ATT_1358192102764_Cougar4_zpsb9977df3.jpg)
http://books.google.ca/books?id=YcAjcSSP4HMC&pg=PA25&lpg=PA25&ots=WucDg7-yKV&dq=cheater+holes+speed&output=html_text (http://books.google.ca/books?id=YcAjcSSP4HMC&pg=PA25&lpg=PA25&ots=WucDg7-yKV&dq=cheater+holes+speed&output=html_text)
Oh snap! Didn't think you'd go all Einstein on us.. ;)
Well the problem with these RC Lander foamies is they don't have proper inlet ducting. They sort of have all sorts of openings where air gets sucked in from. Apparently there is a duct mod guys have done to the Cougar that helps this out and turns this plane into a real rocket. I think Bobby has done it.
I must admit that although my main interest is flying from water, and I'm focussing on a WWI biplane at this point, these EDF jets are looking pretty sweet! Oh so tempting.
All the jets in this build forum look awesome!
Quote from: piker on February 07, 2013, 10:17:49 AM
I must admit that although my main interest is flying from water, and I'm focussing on a WWI biplane at this point, these EDF jets are looking pretty sweet! Oh so tempting.
All the jets in this build forum look awesome!
Piker, do you really need to get into jets?
I mean, do you really have such a competitive need to be better than everybody at everything? ;D
Im losing the plane count, so I have to up my game somehow... ;D
Besides, they're just so sleek and flashy with all those pretty colours!
Hey Rob,
I guess when you are writing "Sleek and Flashy" you refer to the nice fiberglass models that most can not be flown at Temac as the foamy ones are not so sleek unless you spend way too many hours building and painting one...
I hate the fact that I have dings, scratches and dents on my plane only due to handling it and moving it around while building :(
Why not? Michael has flown his habu 32 at temac.
Although sadly most jets have really tiny wheels.
You know what they say about tiny wheels, Mike?! ;)
Quote from: piker on February 07, 2013, 10:17:49 AM
I must admit that although my main interest is flying from water, and I'm focussing on a WWI biplane at this point, these EDF jets are looking pretty sweet! Oh so tempting.
All the jets in this build forum look awesome!
Not to tempt you even further but...
(http://i166.photobucket.com/albums/u98/maniac_316/a2882652-181-008_zpsa834f33a.jpeg)
Fully weathered and detailed RC Lander Cougar
Nice paint job!
Hi Jeff,
I have seen both of these planes - the nice painted one required a lot of work, he completely sanded the original plane and add filler, than sanded again and painted.
First I don't have an air brush but even with a regular brush it will be ALOT of effort for a foamy.
Maiden-ed the Cougar today - one flight only to put a check mark :)
Was nice to take off from the hard snow with no wheels - plane flew very nice - first flight and no trim required.
Was not too fast but I did not add additional openings on the fuse beside the flapy doors that came with it and quite a bit of ducting inside the fuse, not sure what will be the effect with a larger opening and warmer weather is it was quite cold.
Anyhow the sound with the 6s 10 blade is nice and came back in one piece without even freezing too much.
...three maiden's to date this winter - others will have to wait for Temac and good weather:)
-The video is not the best even though I used the new Sony action camera which will probably go back cause I didn't like it too much.
http://youtu.be/NMHckYyhj0k (http://youtu.be/NMHckYyhj0k)
Looks like it flies very nicely, Bobby. And sounds awesome.
I'm jealous! ;)
Quote from: sihinch on February 19, 2013, 08:15:37 AM
Looks like it flies very nicely, Bobby. And sounds awesome.
I'm jealous! ;)
I thought that you bought one?
It was a nice surprise to see it easily take off from the snow and fly nicely with no trim required.
I didn't try to do anything fancy with it but did notice it needs a bit of speed in the turns.
Bobby
Honestly, I was put off this model based on your write up!
I was struggling with fit of parts on my Hunter, and then when I read your discussion about fit on the cougar, and the ducting issues internally, I decided that I didn't want to go through similar frustration with the Cougar.
Can you persuade me otherwise????
.... Well... The ducting thing was based on information from a couple of threads. That was the part that was annoying.
Keep in m
Very nice, Bobby. That winter flying looks so nice while I sit in my warm office ;D
.... Well... The ducting thing was based on information from a couple of threads. That was the part that was annoying.
Keeping in mind the temperatures yesterday I am not sure how it will fly in the summer. Maybe I shouldn't had to worry a about ducting etc. also keep in mind that I am a bit biased cause I don't like Foamies ...
In any case you have significantly more experience than me.
Looks great Bobby. :)
Very realistic scale sound as well!
It should definitely pick up some speed in the summer as well as reduce the amp draw..
Quote from: piker on February 19, 2013, 10:52:53 AM
Very nice, Bobby. That winter flying looks so nice while I sit in my warm office ;D
Yes the temperatures are a bit too low to enjoy I just took it out cause I wanted to see if it flies nothing more :)
It would probably be nice if I could tint that hard bright white and red a bit but I don't have an airbrush and am not sure how to do that without messing everything up..
Just for reference I did a couple of power measurements for static thrust and power.
Max power for the first 1-2sec with a nanotech 4.0A 25-50C is just over 1500W / 70 Amp at low timing. Previous tests with high timing increased the power to over 1700W with not much thrust increase.
I will need to measure the power in flight to compare.
As for static thrust I measured 1550gr with the canopy on and 1870gr without. The plane does not have a cheater hole in the fuse so static thrust is significantly effected from any change - I should probably sand down the inlet steps from the fuse.
I have added a thrust tube to get 80% FSA which is a couple of millimeters smaller then the fuse, I know that this reduces static thrust a bit but should increase speed. The speed measured from the video I took was around 150Kph (94mph), I am guessing the speed will increase in a warmer temperature but am not sure by how much in any case it flew nice but not too fast.
Total weight of the plane with battery is 1810gr.