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Aug 20, 2008, 01:34 AM
My plans are in my blog
Rusty-Gunn's Avatar
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Here are a few pics of the flight this evening. My nephew Nic flew the plane for the first time, and loved it. He was very impressed, and wants to build one now. We'll post a new vid soon.
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Aug 20, 2008, 02:33 AM
Slopeosapien
jonesymj's Avatar
Hey Rusty, I know that you changed motors, but did the 2805 1600 tow it around ok? I have one of those without a home, and I do like your cartoon designs... The Hawg still looks good, and still goes flying with me twice a week at least... Another good cartoon design.
Aug 20, 2008, 02:40 AM
Registered User
Quote:
Originally Posted by jonesymj
Hey Rusty, I know that you changed motors, but did the 2805 1600 tow it around ok? I have one of those without a home, and I do like your cartoon designs... The Hawg still looks good, and still goes flying with me twice a week at least... Another good cartoon design.
You beat me to it . I have the 2805 1600kv and the 2212 1500kv, the 2812 might be too fast not. Would like to start with the 2805 but.

Rudolf
Aug 20, 2008, 12:40 PM
Slopeosapien
jonesymj's Avatar
Rudes, I'm right there with you... I have a larger parkjet motor I could use (a TP2409_12D 1600kv) and it'll pull 165w on a 7x5e clipped to 6.25, but it would only make it scary fast, and heavy too. If I can use the 2805 1600, I can cut out 1 ounce of motor and probably an ounce+ of batttery. Lighter is always better. I've never run any wattmeter tests on the 1600 myself, but I read (on hobbycity) that an 8" pulls 13+ amps... I need to run that motor up and do some tests... If I can keep mine to around 10oz I should be in good shape.

Oh, and I've run the 2805 2840kv on 2 and 3 cells. All the flight tests were done with my H-29 (7oz/200g auw 18"/46cm span) On 2 cells, I found a 5.1x4.5 apc-e (the spoon type) worked great, lots of thrust, and high 40mph/60kph flight speeds. Pulled 9.2a 57w. On 3 cells, apc speed 4.1x4.1 pulled about 100w and made it faster, but the thrust was noticable less. apc 4.5x4.1 pulled 125w, but got the thrust back. and a lot more speed too. I was running 60+mph on the H-29 with this setup, I then moved the combo onto a FSW parkjet that weighed 12.5oz/350g , and it was still fast 50mph/80kph... Tried the same apc 5.1x4.5 on 3 cells, cooked the motor after 5 flights. I thought it was a little too much prop, but it was pulling 160+w, which is a lot for a little $6 motor... I'm gonna try to rewind it, as I have all the stuff here to do it already... Maybe shoot for 2300kv this time...
Last edited by jonesymj; Aug 20, 2008 at 12:59 PM.
Aug 20, 2008, 09:54 PM
My plans are in my blog
Rusty-Gunn's Avatar
Thread OP
I did fly it, but not to any suitable extent, as I'm convinced it was jinxed . It crashed in a water puddle after about a minute of flight, and hasn't worked well since. It hates me.
I'm more pleased with the set-up the plane has now. Extra speed doesn't hurt, as I can choose to go slow anyway, of which I usually fly half throttle (Nic goes "full chroddle" though).
I'll tell you guys this, this plane goes well at slow speeds as it does high speeds. It just needs to be dialed-in, and off she goes. What fun!
Aug 20, 2008, 10:52 PM
My plans are in my blog
Rusty-Gunn's Avatar
Thread OP
Here is the vid of yesterday's flight. the first two portions has me flying the plane, the last has nic flying it (Nic is seen standing in front of the camera.)
My flights were the day before though.
SR-71 Baby Blackbird prop jet, vid 4 (1 min 5 sec)
Aug 21, 2008, 04:43 AM
Look outside the Square
Boxhead's Avatar
Got to Luv the video's Rusty . Where did you start with the CG on this one as it flys an absolute treat.

B x
Aug 21, 2008, 05:19 AM
Registered User
Have to love the comments about the motor Rusty . Thanks for the info Jonesymj, big help also for another jet I am flying at the moment.

Rudolf
Aug 21, 2008, 12:55 PM
My plans are in my blog
Rusty-Gunn's Avatar
Thread OP
Did I forget to mention the CG? I'll have to get back to you guys on this later, after I get off from work. I apologize for this.
Aug 21, 2008, 05:55 PM
Slopeosapien
jonesymj's Avatar
Quote:
Originally Posted by Rusty-Gunn
Extra speed doesn't hurt, as I can choose to go slow anyway, of which I usually fly half throttle
My problem is a complete and total lack of self control, which usually means 4 minutes of 60+ at WOT the whole time, scared to death cuz that's still wicked fast for me in the size of our park, followed by 15 minutes of calming my nerves so I can go at it again. I love airplanes that scare me!!! I'm gonna put my 1600 on the wattmeter stand and see what I can get out of it sometime this week... Daughter's birthday tomorrow though so don't hold your breath...
Aug 21, 2008, 08:27 PM
My plans are in my blog
Rusty-Gunn's Avatar
Thread OP
The balance point to use is 12.75 inches back from the nose of the long-nosed version, or 10.5 from the short-nosed version. You may need to fine tune the CG.
Aug 23, 2008, 03:14 AM
My plans are in my blog
Rusty-Gunn's Avatar
Thread OP
We flew my SR-71 tonight, with the sun already down, with just a hint of light left. My wife made two red streamers for the plane, which I mounted to each nacelle exhaust.
Aug 30, 2008, 02:16 AM
My plans are in my blog
Rusty-Gunn's Avatar
Thread OP
We went out to fly tonight, while Nic flew I took pics and vids. Here are some of the pics. Vids will come soon.
This is one smooth flying plane, I highly recommend it to everyone. Build one, you won't regret it.
Aug 30, 2008, 05:32 PM
My plans are in my blog
Rusty-Gunn's Avatar
Thread OP
Vid #5.
Baby SR-71 Blackbird prop jet (2 min 11 sec)
Aug 30, 2008, 06:22 PM
Look outside the Square
Boxhead's Avatar
Looks like Nic's got it on a String, Rusty. Looks Great and flys Great . I've been slack lately ( winter ) but I just might have too knock one up. I have a couple to finish off so I better pull my finger out .

B x


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