FT mini sparrow powered problems

[hvguy]

Hi all, new here!

Let me start out by saying I am not an expert.

I purchased my first model aircraft the other day from FT (Mini sparrow) along with an (A) power pack which came with a motor, esc, 4 servos and a few other things.

I went to a local hobby shop and purchased some 1000ma 3S batteries, a spektrum DX6i and a Spektrum 6 channel receiver. After assembly "which went quite smoothly with the youtube video" it all seemed well and balanced. This all seemed to change once I tried to fly it. It acted like I never had control over any of the steering even though I could check the controller, mix/rate/expo etc everything was right. The prop span, the elevon's moved in the right direction and all was well. When thrown, it would turn right or left and nose dive. All attempts to pull out or speed up ended in disaster. I then consulted a friend who has been flying most of his life; and even he couldn't figure it out.

Long story short, I ended up ripping the servos and motors out to build something else. In the mean time, I glued the wing on just to keep from throwing it in the trash, because after all... it was my first.

Any idea what could have been wrong?

Thanks!

 

[hvguy]

The only thing I didnt do that I can see after reviewing the video is remove small bits of excess glue on the bottom of the wing. However I cant see this being the straw that broke the camels back.

 

[bimcs]

the cg position may be incorrect!

the cg comes under the spar, about 7cms (2.75 inches) from the leading edge of the wing.

 

[m00ndancer]

the cg comes under the spar, about 7cms (2.75 inches) from the leading edge of the wing.

You might be right, on the plans it's 1.75, but in the video, as you pointed out, it's just under the wing spar.

Have to try that out next time I'm out flying. (2-3 weeks from now)

 

[mklages]

I just built one yesterday and had to put a 2200mah batt up front to get the cg right it's tail heavy plane
Total weight 450gm
motor park 370 with 8x4




I Hope it flys

 

[dgrigor02]

If it doesn't work out, With that motor and weight give a 120% version a try.

 

[hvguy]

I appreciate all the input!, mklages, let me know how it flies. After strolling through hobby lobby I picked up a foam glider for $15 and decided to power it in hopes that the larger wing span will help. After flying it tonight with a headlamp it seems I'm having the same issue, I basically can't control anything other than the throttle.... I feel like I'm doing something wrong. (for reference, I'm 6' tall)

 

[Foxbodyford]

Same results that I had when I first built my Sparrow. Me and my brother in law each built one with the only difference being i used a 2206 motor with 6" prop and he used a 1704 with a slightly less pitched prop. To get mine to fly (obviously my motor weighed more) i had to add about 20 pennies in the front of the plane and have a 3S 1000 at the nose to balance it. STILL it had to be launched with some force and throttle at about half or better. Once flying and moving fast the plane still flew terrible. Seemed to be on the edge of just falling from the sky if i turned too sharp, throttled up too much or down too much.

That night i cut the rear skid off, added velcro to the underside and put the 3s as the front of the plane like I do on some other foamies. Launched a little easier, even with 50% throws and -40% expos the plane was very twitchy but didn't have to have as much speed to maintain flight. It was not a relaxing flight though.

So I did like any frustrated person with little regard for 1$ of foam board would do and climbed as high as I could and purposely nose downed the plane into the dirt. It felt very good.

ON THE OTHER HAND, the plane sustained VERY little damage, even with the pennies in the front of the plane on minor wrinkles. So I removed my electronics, took the fuselage and tore it up then mounted the wing on a modified FT flyer style non swappable fuselage and now I have the cowbird, or possibly a seagull. (Ft flyer/sparrow plane) that flies very well, balances great and is as relaxing to fly as my FT flyer with a K2, AND it only took me about an hour and a half to "design" build and test the plane. 5 or 6 full packs into it and it flies great. Even let my 12 year old try, terrible decision but the plane will live.

 

[hvguy]

Interesting! Glad to see I'm not the only one having some technical difficulties. What was your longest flight with the sparrow?

 

[Foxbodyford]

In its stock form I could get an entire pack out of it however it had to be launched at over half throttle, and tossed with some pep. I had to maintain a lot of speed while flying and when landing it would stall at much faster speeds than needed for landing.

My brother in laws seemed to fly a bit better with the much smaller motor, however he also ran the same batteries and a stack of pennies for ballast. I believe if i had put a 1300 or slightly larger batter up front then the plane would have flown better, however following the plans I had no luck. Moving the CG from 2.75 from wing edge up to 1.75" made a huge difference, but still not enough to make it enjoyable. I may post picks of the cowbird later.

 

[hvguy]

Interesting! post pics when you can.

 

[mklages]

Thanks for the good info maybe i can keep mine in one piece LOL. I have not been in the air yet so this plane will not be the first thing i fly. I have a f-22 and a stoch that i had to put on a diet and i now call it the ugly bus!

 

[French]

Moving the CG from 2.75 from wing edge up to 1.75" made a huge difference, but still not enough to make it enjoyable.

First time poster and brand new to the hobby...

I'm about to begin my Sparrow build and still have some confusion related to the CG. I read in the swappables forum that is should be 2.75. I'm also hearing that a lot of people are having troubles flying this build.

I'm planning on powering mine with the MT 1806. I have the 6030s that came with the Power Pack A kit and also picked up some 5030 tri-blades. I have a 800mAh 3s from FT, and I picked up a Nanotech 1300mAh 25-50C after reading about so many people needing to add nose weight to balance this bird out. I assumed I can't get more flight time out of clay or pennies, so if I need more weight I might as well try a bigger battery (perhaps a total n00b mistake). I ordered the 5030 triblades because I assumed that the closer I could get the motor to the CG (and clear the Vtail), the less nose weight would be needed. I also read that the thrust angle on this build may need to be adjusted.

I'm getting a little anxious about this build, setup, and maiden. Did I pick the wrong build for an RC virgin?

 

[Winglet]

French, Yes, total wrong build for your first. Just throw together a FT Flyer without a landing gear. You will be much happier.

 

[finnen]

The sparrow is not a beginner plane. The ft flyer is easy to build and fly, and the tiny trainer flies better, but is a little more complex to build.

 

[Grey Beard]

Foxbodyford, I somehow completely missed getting any pics of the sparrows or the cowbird the whole weekend. I thought the cowbird turned into a spectacular design. Very versatile and an absolute joy to fly. Maybe we can work on V2 ( or at least V1.1 ) next time and maybe at some point put some plans together for it.

 

[hvguy]

French, Yes, total wrong build for your first. Just throw together a FT Flyer without a landing gear. You will be much happier.

I agree about the sparrow, nor me or a buddy could fly it. Gonna look into an FT flyer

 

[hvguy]

Since im working on a powered glider, ill start another thread. Keep an eye out.

 

[Mistrbojangles]

Build the sparrow as my first build and plane. Only been flying multirotor for a year now. I used a dys 1806 motor with a 5030 prop and a 3s 1300 battery. First couple launches it would fly on an angle and crash into the ground. What I found to be the issue was the elevons not generating enough lift and they were uneven. I changed to pitch to generate more lift and evened them out the best I could using sub trims. Bump throttle up over half and launch. Got it up about 75ft and had enough room between it and the ground to get a feel of how it reacts to stick movement. From there i was able to do a couple speed runs and loops. Flying with the wind you could completely cut the motor and just glide. Flew over 20 minutes and the battery was at 11.7 volts. Had a few crashes last time I flew it and it started to bow the body throwing off the elevons pitch. Since that I took it apart and started to build a new one. Going to make it alot stronger.

 

[duckduckgoose]

A bit late to the party, but the sparrow flies great with a longer nose. Added a 10cm extension "slip on" nose (125% of the original nose) and add a little weight into that and it balances well. It was my first plane that flew for me. But yeah it races like the devil, especially with a larger motor. But yeah not a great beginner plane, and after flying that, the tiny trainer and simple cub were sooo much easier