Mini Scout - Maiden. Looking for some feedack.

[Mode 1]

Hi All,

I took my Mini Scout out for it's maiden tonight. I did not install the landing gear so I launched it just over half throttle and watched it fly away.. always a great feeling when everything goes as planned.

Under half throttle, it flew pretty darn nice. It wobbled a bit and i'm not sure if it was the wind (which was minimal) or the plane. At times I would cut throttle and let it glide around.. I was surprised at how it well it floated, pretty much flying itself.

Above half throttle things got interesting. The more throttle I gave it, the more it wanted to climb and turn to the right. Anything near full throttle was pointless as it required a good deal of down elevator and left rudder to keep it straight and level. Any turns to the right at or near full throttle wanted to quickly throw the plane over into the violent "I want to roll but I only have a rudder" maneuver.

I'm wondering if anyone has any feedback / suggestions pertaining the climbing and wanting to turn right issues above half throttle. Also, to a lesser degree, what are the common factors that cause wobbling in a small plane like this?

I am running a Lumenier RX1806 2500kv with a 6x4 prop on a 2S 350mah. CG was good.

As always. Thanks!

~ Dave

 

[Merv]

The wobble is just a bit of turbulence, don’t worry about it. You just need some trim. I always trim my plane to fly at full throttle.

 

[Hai-Lee]

I could be wrong but it sounds like you might have too much right thrust and insufficient downthrust. The wanting to climb on throttle could be as a result of a minor build issue but increasing the down thrust should compensate for it.

To alter the thrust angles all you need to do is to loosen the motor, fit a shim in the appropriate place and then retighten the motor.

Another thing to check is that your motor spins in a CCW direction when viewed from the front and that the propeller is a CCW prop. Fitting a wrong direction propeller can make handling at high throttle almost impossible due to "P" factor.

Just some things to check!

Have fun!

 

[Mode 1]

The wobble is just a bit of turbulence, don’t worry about it. You just need some trim. I always trim my plane to fly at full throttle.

Thanks for the reply, Merv. I understand the logic, but wouldn't that lead to me having a plane way out of trim at other lower speeds?

 

[Mode 1]

I could be wrong but it sounds like you might have too much right thrust and insufficient downthrust. The wanting to climb on throttle could be as a result of a minor build issue but increasing the down thrust should compensate for it.

To alter the thrust angles all you need to do is to loosen the motor, fit a shim in the appropriate place and then retighten the motor.

Another thing to check is that your motor spins in a CCW direction when viewed from the front and that the propeller is a CCW prop. Fitting a wrong direction propeller can make handling at high throttle almost impossible due to "P" factor.

Just some things to check!

Have fun!

Hai-Lee.. thanks. I hate to admit this but I wouldn't be able to tell the difference between a CW prop and a CCW prop. The motor is spinning in CCW direction. Here's better images of the motor / prop.

 

[Hai-Lee]

Hai-Lee.. thanks. I hate to admit this but I wouldn't be able to tell the difference between a CW prop and a CCW prop. The motor is spinning in CCW direction. Here's better images of the motor / prop. View attachment 117774 View attachment 117775

The prop is a CCW prop and if the thrust is forward then the motor must also be set for CCW.

Have a go and the thrust angles but do a single adjustment and then evaluate and do the next and so on. Too much change in one hit can make the effect of the change hard to determine.

have fun!

 

[d8veh]

The downthrust is build into the way you install the motor pod. The back end must be right up against the upper deck and the front end against the block that you cut to let your wires through. The front looks OK in the photo, but is the back right up against the deck?

The side-thrust can be wrong if you installed the motor on the wrong end of the pod. It should noticeably point to the side. If it points straight forward, have a look at the other end of the pod. to see if it's angled.

 

[Mode 1]

The downthrust is build into the way you install the motor pod. The back end must be right up against the upper deck and the front end against the block that you cut to let your wires through. The front looks OK in the photo, but is the back right up against the deck?

The side-thrust can be wrong if you installed the motor on the wrong end of the pod. It should noticeably point to the side. If it points straight forward, have a look at the other end of the pod. to see if it's angled.

d8veh - Thanks. I'm pretty sure the power pod is in properly. it's also got the right thrust as well.

 

[d8veh]

That all looks about right. Unfortunately, I haven't flown my Mini Scout yet, so I can't say if they all do that.

 

[Dante]

You probably need a little less right thrust, I haven't made the mini scout, but with most planes it's hard to get the thrust angle exactly right.

 

[Mode 1]

You probably need a little less right thrust, I haven't made the mini scout, but with most planes it's hard to get the thrust angle exactly right.

Thanks Dante!

 

[Mode 1]

That all looks about right. Unfortunately, I haven't flown my Mini Scout yet, so I can't say if they all do that.

Keep me posted how yours flies

 

[Merv]

Thanks for the reply, Merv. I understand the logic, but wouldn't that lead to me having a plane way out of trim at other lower speeds?

It could be out of trim at slower speeds but not necessarily. High speeds are far more sensitive to trim than low speeds. Your thrust angles could need adjusting as other have suggested. But adjusting the trim is a lot easier. I start there first.

 

[Mode 1]

It could be out of trim at slower speeds but not necessarily. High speeds are far more sensitive to trim than low speeds. Your thrust angles could need adjusting as other have suggested. But adjusting the trim is a lot easier. I start there first.

thanks Merv.

 

[Bricks]

To check for correct thrust angle take the plane straight up and watch what happens. If it pulls to the canopy then add down thrust if it pulls left or tight add shims to the side that it is pulling to.

 

[Mode 1]

To check for correct thrust angle take the plane straight up and watch what happens. If it pulls to the canopy then add down thrust if it pulls left or tight add shims to the side that it is pulling to.

Hey Bricks.

Thanks for the reply. Per the shims, do I insert the shim between the power pod and the fuse or am I doing something with the motor? My motor is screwed directly to the firewall.

Thanks.

 

[Bricks]

Between the motor mounts and firewall, it is the easiest way.

 

[Merv]

To check for correct thrust angle take the plane straight up and watch what happens. If it pulls to the canopy then add down thrust if it pulls left or tight add shims to the side that it is pulling to.

I do the opposite. I take the plane high (2-300 feet), cut the power and put the plane into a straight down dive. Then see which way it pulls out. This puts the plane at high speed with no effect from then motor with an improper thrust angle.

For this to work you must FRIST have the plane trimmed to fly straight & level at full power. If there is an improper thrust angle you will trimmed it out. Then by removing the power and putting the plane into a dive, you can see what trim the thrust angle was causing. Then to correct, if it the plane pulls out upright, you need up thrust. That is, the motor has too much down and you compensated by giving up trim. You need to give the motor up thrust in order to remove the up trim. Likewise If it pulls to the right, you need right thrust.

I've never gotten one perfect. If you plane goes from straight down to level in 75 feet, you've got a problem and need to fix it. If you can dive 200 feet with no more than a few degree deviation, that's good enough.

Trimming to fly straight and level at full power is just something you got to do first.

 

[Mode 1]

I took the Mini Scout out today in some pretty high winds. I had so much fun.. I felt like I was flying a hawk. I'd climb high and kill the power and let it sit there, almost perfectly still hovering above the field. Then i'd roll it over and put it in a dive and let it rip downwind, still without power.
That being said, due to the amount of wind I had no way of telling what kind of results my minor adjustments made to flight characteristics.

 

[buzzbomb]

I took the Mini Scout out today in some pretty high winds. I had so much fun.. I felt like I was flying a hawk. I'd climb high and kill the power and let it sit there, almost perfectly still hovering above the field. Then i'd roll it over and put it in a dive and let it rip downwind, still without power.

Wow, dude. I am not a jealous man by nature, but that makes me jealous. I've got a ways to go on my Mini Scout build, but you have definitely given me more to look forward to.