Slingshot Johnny III Flight Operations Update - RC Groups
Shop our Airplanes Products Drone Products Sales
Thread Tools
This thread is privately moderated by GimpyPilot, who may elect to delete unwanted replies.
Nov 12, 2010, 12:46 AM
T-28C, Extra 300, Beast UMX
GimpyPilot's Avatar

Slingshot Johnny III Flight Operations Update

Flight Operations Update.

The Trojan now has 25 flights on it, half of them at night.

I recently finished off the installation of the new wing mounted landing lights and the E-Flite Power 10 motor. With the Power 10 installed the cg worked out to 2" from the LE instead of the desired 2.5"

To work the balance issue out I installed a light ply plate with some velcro and a velcro strap so that I could install the battery further aft. Works like a champ. AUW with a 2200 mAh 25C battery is now 39 Oz, 9 Oz heavier than stock - balanced right at 2.5". I can feel the weight difference, seems more stable in the wind and a little more ballistic when maneuvering but not quite as light on the controls as stock.

I also switched over to my new DX7 and must say I am impressed, range checked great - programming is a bit tougher than what I am used to on the DX6i but I will get used to it. It is nice having up to 7 custom mixes, plus auto-trim for flaps, etc. The ratcheting throttle is nice too.

Flight performance with the APC prop is outstanding. Acceleration is great, certainly better than I have had a need for when flying scale.

I had to use a washer and cut down a bronze bushing, but I am now able to make the Corsair prop work on the Power 10 prop adapter - looks great, and runs smooth. I used a good Sharpie and put a black band across the yellow tip to get the double stripe appearance -- really happy with how this looks now. It is a little slower than the APC of course, but it looks and sounds great.

The new lights on the wings have helped illuminate the ground before the flare, making night flight fairly benign. The canopy lights give a cool glow.

I also swapped out the HS65MG servo for the main gear mechanical retracts and put an HS82MG in and voila, the gear now swing perfectly at any speed. It is very fun to see the gear tuck away as the flaps come up after takeoff or a touch and go.

I took some 6mm BluCor foam and filled in the nose gear well to try and close it out some and it really seems to have helped. I left enough room for the nose wheel and strut to cleanly move but filled in a lot of the open space, not only is it a bit faster, it also looks pretty nice. I also filled in a little of the main wheel wells just to clean them up too. After the hot glue set, I followed up with Flat White paint.

I now consider the build completely complete. There are no more tweaks or mods, it is all done.

The speed range with the retracts and Power 10 combo is impressive - I was actually keeping up with a 4S Trojan when clean.

With the gear down and full flaps it will literally float by at just faster than walking speed although it takes a fair amount of power due to the drag of the flaps.

Without radar or any other evidence I suspect the plane is now capable of high 60's in level flight (compared to mid-high 50's for stock) and it will climb pretty well. On the 2-blade APC 10x7 it does eventually run out of steam in a climb, but it is pretty small by the time it does.

Of course the drawback to this wide speed range is that trimming is virtually impossible.

With the plane cleaned up (gear and flaps up), I am finding that mixed throttle flying (~60% throttle and up) with the Power 10 actually yields longer flight times than the stock bird on the same batteries. I have the timer set at 9:30 now, and usally get the plane down and secure in just under 10 minutes and have yet to drop below 3.7V per cell even on my original PZ 2100 mAh I bought with the first Trojan more than a year ago.

After finally finishing off the gear mod, I now can really just enjoy flying the bird, and I am doing just that.

Hopefully I can get some action shots at the Wings Over Chino event or some other flying, it looks great all cleaned up.
Last edited by GimpyPilot; Nov 12, 2010 at 12:52 AM.
Sign up now
to remove ads between posts

Thread Tools

Similar Threads
Category Thread Thread Starter Forum Replies Last Post
Discussion FOR SALE:Real Flight 4.5 =G5 Update flyhard51 3D Flying 0 Sep 27, 2010 03:05 PM
Sold Real flight 4.5+ g5 update BIG LACY Aircraft - General - Miscellaneous (FS/W) 4 Sep 18, 2010 01:54 PM
To Slingshot or not to slingshot...that is the question!!! Kirkgh Hand Launch 4 Jul 02, 2005 03:39 AM