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Old Aug 09, 2012, 11:57 AM
Another one on the way...
ysolomon's Avatar
Plano, Texas
Joined Feb 2009
2,339 Posts
By the way, last week, surprisingly, I got a delivery from HK. Two new canopies. Now I'm whole...
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Old Aug 12, 2012, 12:14 AM
Tin Can Sailor
seadog985's Avatar
Alabama, USA
Joined Feb 2009
761 Posts
Man, you must have really got on HK's last nerve for them to send you a replacement canopy. The ones I had made are far less brittle than what came with the plane, so I think I'm better off than trying to fight with HK.

Mattin, how do you cram a 6S batt thru the cockpit? I have a 6S 5000 and I don't think it will fit unless I cut the extra hatch.
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Old Aug 12, 2012, 01:03 PM
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MattinAZ's Avatar
United States, AZ, Gilbert
Joined Jan 2005
1,921 Posts
Qty 2 - 3S5000 backs in series. Block of balsa hysoled at the furthest point that I wanted the batteries to go into the fuse and some velcro straps hysoled to the bottom of the fuse for battery securing.

Matt

Quote:
Originally Posted by seadog985 View Post
Man, you must have really got on HK's last nerve for them to send you a replacement canopy. The ones I had made are far less brittle than what came with the plane, so I think I'm better off than trying to fight with HK.

Mattin, how do you cram a 6S batt thru the cockpit? I have a 6S 5000 and I don't think it will fit unless I cut the extra hatch.
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Old Aug 13, 2012, 01:19 AM
Tin Can Sailor
seadog985's Avatar
Alabama, USA
Joined Feb 2009
761 Posts
Thanks. Thought you might be using 2 3S batts. Will have to consider your idea.
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Old Sep 23, 2012, 07:42 PM
Gorilla Glue Expert
PikeStaff's Avatar
United States, PA, Doylestown
Joined Sep 2010
2,643 Posts
Howdy.

Subscribing.
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Old Oct 20, 2012, 10:00 PM
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Flip Flop's Avatar
United States, UT, Layton
Joined Oct 2009
524 Posts
Has any one flown this with tailerons using the ailerons for flaps?

Didn't see if anyone has in the thread.
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Old Oct 21, 2012, 02:18 AM
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Boostoman's Avatar
Oman, Masqat
Joined Apr 2010
320 Posts
im planning to do that on my next flight.
I used my foamy HK 70mm sport jet as a test for this and it worked well, you hast need to mix in with it a bit of elevator.. but keep in mind that you need to align the aircraft to the runway before activating the flaprons
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Old Oct 21, 2012, 08:48 PM
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Extremeflyer's Avatar
United States, CA, Rancho Cucamonga
Joined Feb 2009
119 Posts
Confused???

Well, here I am back at it again. After a long break, I have managed to finish the repairs on my KMP F-18. Back a few months ago I tried to maiden this EDF with disastrous results I figured that I had everything right CG, control throws, etc, etc. But the flight was very short, and didn't end well. Now my question is what went wrong? I'm not new to EDFs but this one has me quite puzzled. I've read this thread from start to finish and took my time building and setting up this jet. So here is the set up, the motor is a HET 700-60 1485kv with HET 9305 fan unit, CC 75A ESC on 8s 4000mah 40C Zippy Flightmax batteries. I had this same power set up in my Fly Fly F-86 and it flew great with plenty of power. The F-86 was a much bigger jet than the F-18 so I figured it should be fine in the F-18. My total weight with batteries is 7.5 lbs. On the maiden it came off the ground in a short distance(maybe to soon?) and piched up like it was tail heavy. I managed to gain control but it didn't seem to have the power to pull out and circled like a feather in the wind and slamed level onto the ground from 6ft. completely damaged the gear and some cracks in the airframe. I set the CG 85mm and made sure it was a bit nose heavy. So I do not believe that I have a CG issue? What I am starting to wounder is I might have pulled up to soon. From all the videos I've seen on this thread it looks like it needs a long run to build up speed before it gets airborne. If any one has some suggestions I'm all ears
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Old Oct 21, 2012, 09:16 PM
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bri6672's Avatar
San Diego
Joined Jul 2009
2,236 Posts
Stick with 80mm on the CG to be safe.

Need some more info.

1) did you modify the exit diameter of the thrust tube?

2) did you modify the linkage in the horizontal stabs?

Answers to these questions will give you the answer I have had a few of these and they have their issues but can be resolved with some modifications.
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Old Oct 21, 2012, 10:08 PM
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Extremeflyer's Avatar
United States, CA, Rancho Cucamonga
Joined Feb 2009
119 Posts
I did cut back both ends of the thrust tube. Do you recommend a specific diameter? And I did modify the horizontal stabs. I'm also wondering about the power to weight ratio. To me at 7.5lbs it feels like a flying bowling ball.
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Old Oct 21, 2012, 10:47 PM
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bri6672's Avatar
San Diego
Joined Jul 2009
2,236 Posts
Thrust tube needs to be opened not just cut back, I need to measure mine to give you the proper size, with out opening them then you will be flying around in fifth gear all the time,

The horizontal stabs are the most common culprit to the tail heavy feel you had, if there is any flex or slop then you need to go back to the drawing board on your mod.

They also list a lot of expo for the elevator in the manual, in my opinion it's way too much especially if you have any flex or slop in the stabs, you will be pulling up elevator to compensate for the slop or flex and then you hit the expo curve and it will pitch the plane.

7.5 lbs is totally fine but if its flying heavy then you need to look at expo on the elevator, if you have too much the plane will feel sluggish and heavy. The thrust tube being to small will also make it feel under powered until it really gets going, it will have good top end but will need a lot of power to fly, again making it fly "heavy"
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Old Oct 21, 2012, 11:38 PM
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Extremeflyer's Avatar
United States, CA, Rancho Cucamonga
Joined Feb 2009
119 Posts
Yes please, if you can give me your measurement on the thrust tube exit. And thanks again for your help it's much appreciated
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Old Dec 04, 2012, 09:52 AM
Why kamikaze pilot wear helmet
mikes68charger's Avatar
United States, OH, Columbus
Joined Jul 2010
1,074 Posts
I know not scale but I got a nice pusher set up doing 14k on a 12x12 with 5000mah 6s 40c

I can't find a prop jet that I like the looks. Do you think this bird can fit a 5000mah 6s Lipo? Will 10pounds thrust with 145mph prop speed be ok

Also will the eflite 60-120 electric retracts fit as I have exstras?
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Old Dec 04, 2012, 05:05 PM
3DHOG
jcdfrd's Avatar
USA, CA, Aromas
Joined Sep 2010
4,815 Posts
Quote:
Originally Posted by Extremeflyer View Post
Yes please, if you can give me your measurement on the thrust tube exit. And thanks again for your help it's much appreciated
as large as the fuse will allow, if I remember we had ours around 51-52mm each exit, not an easy mod but pays big dividends. there are pics in this thread of ours I believe
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Old Dec 04, 2012, 05:09 PM
3DHOG
jcdfrd's Avatar
USA, CA, Aromas
Joined Sep 2010
4,815 Posts
Quote:
Originally Posted by mikes68charger View Post
I know not scale but I got a nice pusher set up doing 14k on a 12x12 with 5000mah 6s 40c

I can't find a prop jet that I like the looks. Do you think this bird can fit a 5000mah 6s Lipo? Will 10pounds thrust with 145mph prop speed be ok

Also will the eflite 60-120 electric retracts fit as I have exstras?
a 12x12 prop wont clear the ground especially a pusher, after rotating on take off it will be a 4x12 prop

those retracts are way too big, we use eflight 15-25's and they are a perfect fit and match to this airframe, just expensive
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