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I'm building the TopRC F9F Cougar

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I'm building the TopRC F9F Cougar

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Old 05-25-2018, 04:40 PM
  #76  
Jonboy2
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Originally Posted by Pull Up Now!
Did you see the video I posted showing the nose gear doors working?
I did see the video and they appear to work nicely. I was hoping you could share a little more detail as far as how you designed your closing/opening mechanism. I know you said the stock mechanism was not reliable and you designed your own that works much better.
Old 06-04-2018, 06:04 AM
  #77  
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For sale ads and replies were removed because discussion forums are not the place for ads, feel free to use the Marketplace.

Thanks
Old 06-04-2018, 07:13 AM
  #78  
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Originally Posted by Jonboy2

I did see the video and they appear to work nicely. I was hoping you could share a little more detail as far as how you designed your closing/opening mechanism. I know you said the stock mechanism was not reliable and you designed your own that works much better.
They pulled the add. It's in the market place now. I pm'd you back You can text me at 806 773 1249
Old 06-10-2018, 12:06 PM
  #79  
sweetpea01
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  1. Anyone have flap/brake throw settings for mid and high? Also where you measuring from? I'm doing my flaps now
Old 06-10-2018, 03:16 PM
  #80  
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Originally Posted by sweetpea01
  1. Anyone have flap/brake throw settings for mid and high? Also where you measuring from? I'm doing my flaps now
I just measured for someone else who asked - I have 1.5" of deflection at takeoff setting and 4" of deflection at full flaps. This is measured at the point of maximum width of the flap - from the "V" point on the flap back to the fuselage.

Bob
Old 06-28-2018, 07:04 AM
  #81  
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Maiden mine last week with a Bee 80
I was worried about power because I'm flying over 7000 feet of altitude, and we lost 30% of the nominal thrust here
I ended up fliying at half power most of the fligth and only whent full power for take off, verticals and a couple of high speed passes
Great plane overall and only modification was to the fuel tank, I moved the stoper to the center of the tank so the clunck can go all the way up and down
Old 06-28-2018, 08:27 AM
  #82  
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Building another Cougar. I had the Skymaster X-treme F9F, now building the TopRC kit. The TopRC jet looks to be much better built, and the paint is MUCH better than the SM. Paint from the SM Cougar would come off in my hand when I picked it up...
Using MKS HV747 & HV1220 servos. Gear is painted, but work keeps getting in the way of my hobby. Planning to power with a JetCat P100RX. This one's gonna take a while. Most of these pics are from my SM Cougar, painted the bottom white, main gear doors added, Fei Bao F9F cockpit added.

Last edited by patniven; 06-28-2018 at 08:31 AM.
Old 09-18-2018, 04:57 PM
  #83  
TimD.
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OK., I just got around to finishing mine up this week. Where did you guys figure your CG at. The online manual states 175mm back from intake lip . That is way off according to my calculations of the wing/fuse planform. I came in at 11 1/2"" - 285mm back. OR 4 "- 100mm in front of the rear spar / 1" - 25mm in front of the mains.

I will probably move it forward a bit more to be cautious for the first flight.
Old 09-18-2018, 05:39 PM
  #84  
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See post number 56
Old 09-19-2018, 10:10 AM
  #85  
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Originally Posted by TimD.
OK., I just got around to finishing mine up this week. Where did you guys figure your CG at. The online manual states 175mm back from intake lip . That is way off according to my calculations of the wing/fuse planform. I came in at 11 1/2"" - 285mm back. OR 4 "- 100mm in front of the rear spar / 1" - 25mm in front of the mains.

I will probably move it forward a bit more to be cautious for the first flight.
= = = = = = =
The instruction book calls for 175mm back from the wing indentation (and handy-dandy panel line) - NOT the lip. Several other threads exist, and Bob Klenke had his at 185mm when we talked. I maidened at 185 and am moving it back (due to the amount of up elevator needed) as did he. I will try to pull the plane down tomorrow night (have a meeting until late tonight) and look at where you have it measured vs where I am now.

Greg
Old 09-19-2018, 03:51 PM
  #86  
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Thanks Guys, Feel kinda stupid as I knew I saw it somewhere RCU?RCG but could not find it. I even scanned this thread before asking. Hah
Old 10-02-2018, 07:57 AM
  #87  
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I initially flew my Cougar on a Jetcat P-60. It flew great and was very scale. However, the takeoff rolls were long and I was flying at 3/4 throttle or more most of the time. It was also obvious that flying off of grass with the P-60 wasn't going to be possible.

So I upgraded the Cougar to a Kingtech K85G2. I must admit that its much more fun now. Takeoffs happen in less than 200' (more like 100'), and its quite fast at full throttle. Its not exactly "scale-like" flying, but it does have more margin given the excess of power. Fuel consumption did not change significantly - it might e *sightly* better with the K85.

I'm also still moving my CG back a little at a time.

Bob
Old 11-03-2018, 11:17 AM
  #88  
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RE: Saddle fuel tanks.......has anyone installed saddle tanks (Sullivan 16oz) on this plane. I installed them on each side of the turbine therefore making them behind the CG. If you have, what affect did it have to the CG? and if so what did you do? I am using a P100rx and felt like I needed more capacity than the stock 68oz. I now have 96oz and should get 8-9 min flight. Concerned about the CG. Any help appreciated.
Old 11-03-2018, 03:55 PM
  #89  
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i have this jet, though 100N is a lot. Mine has 80, because that size gave me 8 min flights without enlarging the tank. Just make sure you plumb the fuel system to empty the aft tanks first
Old 11-03-2018, 06:33 PM
  #90  
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Originally Posted by [email protected]
RE: Saddle fuel tanks.......has anyone installed saddle tanks (Sullivan 16oz) on this plane. I installed them on each side of the turbine therefore making them behind the CG. If you have, what affect did it have to the CG? and if so what did you do? I am using a P100rx and felt like I needed more capacity than the stock 68oz. I now have 96oz and should get 8-9 min flight. Concerned about the CG. Any help appreciated.
I installed an 8oz tank in front of the main tank opposite the UAT. I find that after I fly for 5 minutes I'm ready to land and I always have 1/4 of the main tank left. I've never gotten into the fuel in the 8oz tank. The K-85 is a very fuel efficint engine - it burns the same amount of fuel (maybe less) than the P-60 it replaced.

The P-100 is *a lot* of engine for the Cougar...

Bob
Old 11-04-2018, 08:24 AM
  #91  
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Originally Posted by rhklenke
I installed an 8oz tank in front of the main tank opposite the UAT. I find that after I fly for 5 minutes I'm ready to land and I always have 1/4 of the main tank left. I've never gotten into the fuel in the 8oz tank. The K-85 is a very fuel efficint engine - it burns the same amount of fuel (maybe less) than the P-60 it replaced.

The P-100 is *a lot* of engine for the Cougar...

Bob
I think it's difficult to compare your fuel/engine combo with a 100N engine whose burn rate is much higher. Before I put the Kingtech 80N in my F9F, I had intended to put in a 60N based on website and the manual's recommendation. These power suggestions were wrong in my opinion, expecially with grass fields. So, I had to eat the 60N and buy an 80N in it's place. But it was a financial burden to do that. I'm suggesting that it may be the same burden to replace the 100N with a more fuel efficient turbine, thus he's looking for a way to just add more fuel.
Old 11-04-2018, 09:10 AM
  #92  
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The P100rx burns 12 oz per min. With a 68oz tank leaving 20% for emergency, that only gives me a 4.5 min flight. Your right, I have the 100 and do not want to have to spend more $ need the extra capacity....whata bout adding 1/2 the weight of the fuel in the saddle tanks to calc the CG?
Old 11-04-2018, 10:19 AM
  #93  
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Originally Posted by [email protected]
RE: Saddle fuel tanks.......has anyone installed saddle tanks (Sullivan 16oz) on this plane. I installed them on each side of the turbine therefore making them behind the CG. If you have, what affect did it have to the CG? and if so what did you do? I am using a P100rx and felt like I needed more capacity than the stock 68oz. I now have 96oz and should get 8-9 min flight. Concerned about the CG. Any help appreciated.
Yup, I have. I balance at 185mm and absolutely no issue on flight performance (other than being a little heavy on climb-out. I have a Wren 70 in her, located a bit further forward than in the picture (ground out the flange on the inside of the intake duct when the stock pipe imploded - so new pipe from Gary Mueller, and moved the engine forward.) I have the adhesive felt/aluminum insulation on the outside of the tanks from Aircraft Spruce just to help with keeping the fuel cool.

Tanks are in series, draining the saddle tanks 1 and 2 then the main tank 3 and finally a 2 oz UAT. I fly for 8-9 minutes and land with a safe reserve in the main tank.
All this is at 7000 feet.

Hope this helps!
Greg
Old 11-04-2018, 11:07 AM
  #94  
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Jetflyr.................wow thanks your picture is exactly like the way I have my tanks set up as well. Is your tanks 16oz each? If so, should be the same amnt of weight.....Just to confirm, you balanced at 185mm WITHOUT FUEL. I have my tanks set up on a tee. The two saddle tanks should be used at same time before the main tank is used. Do you think this is ok? Just for info, do you remember how much weight you had to put in the nose for balance?
tks
Old 11-04-2018, 11:41 AM
  #95  
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Adding nose weight for half the weight of the fuel and tanks is splitting the baby, which is one approach. You'll be a bit tail heavy during the latter parts of the flight, and landing. The Cougar flies and lands well, so you may be just fine. I'd prefer not to add any extra weight at all. Is there room on top of the existing tank for a flat tank? For a plane this nice, a custom tank would worth the investment. Here's a pic of my jet with all kinds of stuff on top of the tank. There's room for a big flat tank there. I can put you in touch with a guy to build a custom tank that'll fit there like a glove if you are interested in this route. The advantage? No added nose weight and only 1 new tank instead of two. Notice the picture of the other guy above who did saddle tanks. He didn't use a tee, all three tanks are in series. This is an advantage over using a tee because unequal fuel flow won't leave one saddle tank with a little fuel in it.
Old 11-04-2018, 01:49 PM
  #96  
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Originally Posted by [email protected]
Jetflyr.................wow thanks your picture is exactly like the way I have my tanks set up as well. Is your tanks 16oz each? If so, should be the same amnt of weight.....Just to confirm, you balanced at 185mm WITHOUT FUEL. I have my tanks set up on a tee. The two saddle tanks should be used at same time before the main tank is used. Do you think this is ok? Just for info, do you remember how much weight you had to put in the nose for balance?
tks
Yup, I balanced 185mm without fuel in the tanks - but 2oz in my UAT up front. The saddle tanks are Sullivan/Pylon 12oz saddle tanks, and they are in series. (I prefer series since they drain completely, and they are so close to the center line that it is not an issue).

Before I put the saddle tanks in I needed 4 -6 oz of weight in the nose, no change with the saddle tanks.

First flight was main tank only, then a single saddle, then both. The airplane didn't know the difference other than the extra weight for the first few minutes of the flight.

Do make sure you reinforce you main gear mounts before you have everything in the airplane .... they will need it!

Hope this helps!
Greg

Last edited by jetflyr; 11-04-2018 at 05:06 PM.
Old 11-04-2018, 07:07 PM
  #97  
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I just saw your post on the other forum ..... it appears you have "regular" Sullivan 16 ounce tanks in there (rectangular).
I am using the Sullivan/Pylon 12 ounce SADDLE TANKS from the old DF days. Much thinner and curved, which fits the usage here, better.
Greg
Old 11-05-2018, 06:12 AM
  #98  
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Originally Posted by Pull Up Now!
Before I put the Kingtech 80N in my F9F, I had intended to put in a 60N based on website and the manual's recommendation. These power suggestions were wrong in my opinion, expecially with grass fields.
Hello Pull Up Now
When I first read this thread, I was very concerned to put a Bee 80 in this airframe because I fly at 7000' altitude, we lost here near to 30% of the thrust (and the lift)
It turns out that the power was more than enough and it fly’s for 8 minutes with plenty fuel to land, and feels like a sport jet
Only modifications I made were to the fuel tank, I made a new stopper hole a little lower than the center, so the clunk could travel from the bottom of the tank to near the top
Old 11-05-2018, 11:10 AM
  #99  
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Well I have received a lot of suggestions....a couple have said they made no change to the CG with the additional tanks. So what I think I am going to do is balance the plane dry, then fuel it up and see if there is a significant difference. After seeing the results, ,if in fact is becomes noticeably tail heavy I may add a little more weight to the nose and try to make it 50/50 at takeoff and landing. I am at 5300 ft and want the extra thrust of the 100 but also do not want to have to spend more $....the throttle does not have to go all the way to the top
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Old 11-05-2018, 04:52 PM
  #100  
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Did you consider putting the extra tank on top of the existing one?


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