Giant twin Sparrow: more amazing than you would think

[Dr. Looping Looie]

In Flite Test fans Ive Seen someone doing a 200% version of the sparrow, and instantly some cool ideas came to my mind: lighter wing loadind, more space, more funktions. But instead of b- or c-pack, I used the F-pack. And I was not disappointed with the performance: from 10mph crawls on 3s up to rocket like acceleration on 4s! But the coolest thing is the ability to upgrade it: exchangeble landing gear, lifting things up, STOL stuff and FPV to name just a few. And Ive included a whole new wing mounting system.

 

[Dr. Looping Looie]

New pictures of wing mounting and landing gear:

As you can see, the wing is mounted using skewers. I added wooden pieces for more stability. This method connects the wing very solid to the fuse. Rubberbands would be too short dir such a big wing and the wing could move around a little. The landing gear uses the same technique as the simple cub and scout, its just bigger. The wheels come from an E flite Timber. Theres also a cutout for a bomb bay, my next upgrade.
And heres a short flight Video:

 

[donalson]

I'm one of the 200% sparrows on FB... the white one with the bronco nacelles very nice... your skewer wing mount is much cleaner than my rubber band mount.

I'm looking forward to flying it especially after that video of yours.. I'm expecting a lot more adverse yaw on mine cause of how I did my ailerons... but looks like it's goiing to be a nice flier...

I still do wonder about doing a pusher version... the C pack motor should be enough... but for now twin tractor is how Im going.

 

[Dr. Looping Looie]

If you want to do a pusher, keep in mind that you are adding weight behind the CG. You will have to add lots of balance weight. Looking forward to your flight video!

 

[donalson]

Initially I had it built to push... took 3 2200 3s lipos to balance

 

[Dr. Looping Looie]

I made some crazy stuff, added bomb door for parashutes and tow release for banner pulling and glider tow and a float. Today, I was able to test it and I really like the water handling.

I had a ton of fun at the lake. I even managed to land it in my hands.

 

[donalson]

I saw you post this on FB... the videos make it so much more awesome

do you have some better pics or even some basic plans for the center skid? I think i'm going to have to try this out... although I think a sea duck or sea otter wing skids/skis will prob be an addition I toss on... but I suppose that means water proofing the white foam board doh...

 

[donalson]

oh also what size lipo are you running?... I'm debating on mine... I can balance it with a little extra weight up in the nose and a 2200 3s... but with it's size I'm thinking two 2200 3s lipos would be a better choice...

 

[Dr. Looping Looie]

The batteries I use are 2200 3s and 4s and 1200 3s without any balance weight. That keeps the total weight under a kilo. And Im running twin F-pack, which really is not underpowered.

 

[donalson]

that under kilo AUW with lipos and everything?... looking closer you didn't run doublers the length of the fuse and went with some structure inside... little over 1.1kg with 2200 3s... if/when I rebuild I'll prob do something similar...

 

[Dr. Looping Looie]

The structure inside is mostly because of the bomb bay and landing gear slot. One of the Key factors may also be that I made a very light spar in the wing. How did you make the Spar?

 

[donalson]

The structure inside is mostly because of the bomb bay and landing gear slot. One of the Key factors may also be that I made a very light spar in the wing. How did you make the Spar?

4 sheets of foam thick to keep proportions the same as stock (stock is 2 sheets thick), cut a notch to fit and glued in a CF arrow shaft... I did remove the foam on the spars... but I could have made it lighter... I also did remove a lot of paper while building, pretty much everything inside the fuse.... also two B pack motors with 30a ESC with BECs is overkill...