Ship seems light on the lines for the speed the ship is flying at.

[Dennis Toth]

I just finished my new Barnstormer, at take-off it is 38oz, 60' C to C 0.012 cable lines, lap time 4.65. The ship flys fine but for the speed it is flying it feels light on the lines. There is a slight bit of rudder offset and 1 deg of motor offset (I did check the prop ends and on the 10" prop it is 1/8" offset). Wings are level, leadouts are 1/2" back from the CG. It should be pulling ~7 - 8ish lbs and feels like 5. I have a Still Stuka which is just about the same weight as and lap time on same length lines and it is a solid pull like 7. Any idea what could account for the light line pull?

Best,    DennisT

[Dave_Trible]

I just finished my new Barnstormer, at take-off it is 38oz, 60' C to C 0.012 cable lines, lap time 4.65. The ship flys fine but for the speed it is flying it feels light on the lines. There is a slight bit of rudder offset and 1 deg of motor offset (I did check the prop ends and on the 10" prop it is 1/8" offset). Wings are level, leadouts are 1/2" back from the CG. It should be pulling ~7 ish lbs and feels like 5. I have a Still Stuka which is just about the same weight as and lap time on same length lines and it is a solid pull like 7. Any idea what could account for the light line pull?

Best,    DennisT

Dennis it would be hard to compare one design against another quite different airplane.   At that speed and weight you'd expect to hang out there pretty well however things that could work against you besides lead out position could be the longer inboard wing creating more inboard drag and the CG location.  On the older ships like this they weren't afraid of more engine and rudder offset-sometimes a lot.  If it were me I'd shorten the lines to about 57'.  You can add some nose weight which will add some tension to a point-and adjust the handle line spacing more open if the response feels slow. This will also functionally move the lead out location further back.  If you can twist in more engine offset and perhaps rudder offset if it was built with less than the amount shown on the plans that would help a lot.

Dave

[Ken Culbertson]

Is it light on the lines meaning it feels like it wants to come in at you or does it just not pull hard?  Do you have an unusual amount of rake?  Have you added tip weigh till it starts to hinge then backed off?  I have had two Barnstormers a long time ago and I don't recall them pulling very hard.  I like a plane that pulls hard (to a point).  Good luck, they are a lot of fun.

Ken

[Joe Gilbert]

Half inch behind CG not enough in my opinion. Move back to one inch if that doesn’t help may be time to get some rudder offset and or add noise weight. Keep us posted

Joe Gilbert

[Steve Helmick]

Gotta ask, for which I apologize in advance. Is this Barnstormer IC powered or 'lectric? Because 'lectrics are said to need the CG farther forward and LO's farther aft. You did refer to "motor offset", instead of "engine offset", so....  Steve

[Dennis Toth]

Ty,
On my ship I revised the LE sheeting to match the original plans and kept the second spar as you described. I know Lou Andrews was an accomplished free flight flier so I thought he had a reason for that second spar being exposed. I built the ship with the nose shaped to the spinner like the picture on the original box. I have two fuses one electric (this is the one I am flying cause our field is not noise friendly) and the second for IC which is still in the final build stages.

Where does your Barnstormers balance? Mine are right on the end of the leading edge sheeting. How are your leadouts positioned? Mine are 1/2" back from the CG.

Best,  DennisT

[Joe Gilbert]

My is 38 oz cg 1 1/2 from leading edge leadouts center is 1 1/8 back of cg.

[Dennis Toth]

Joe & Ty,
Thanks for the information. What lines are you flying on? I am on 0.012" cable, 60' C to C. I did a test flight today after adjusting my line spacing and overhang (Kaz handle). It is getting close to the overhang in the old E Zjust. Seemed a little better, might move it out one more 1/8". I have to get used to the look of the ship in the air, but I'm getting used to it.

Best,   DennisT

[Joe Gilbert]

Fly mine on 58 foot eye to eye .15  hot rock style Handel.

[Dan McEntee]

   I'm not sure what the concern is about the amount of pull, as long as you are confident that it's solid on the end of the lines and not tending to turn in or gets any lighter at 45 degrees or overhead. One thing that has not been mentioned here I think is tip weight and what you have loaded on the model. I would add tip weight until you see an adverse reaction and then back off. Just add tip weight, no other changes. You might even try a "Fancher" and ballast the model up a few ounces on the balance point and see how it reacts.
  Type at you later,
   Dan McEntee

[Dennis Toth]

Dan,
I have like 0.65oz tip weight, so I could do more. I am increasing the handle overhange to match the old EZjust which move the arms out 1/8". It is not that I need gorilla pull but I like a solid feel.

I am still at the stage of matching prop diameter/pitch/lap time with allowable pack size. Right now I have a BadAss 2814 870kv motor running on a HobbyStar 5S 1600mah pack. Prop is an APCE P 10 x 6.5 ish at 9700 fixed rpm. I think this will get through the OTS pattern in 4m 40 sec. I am working on finalizing this setup.

Best,   DennisT

[Dan McEntee]

Dan,
I have like 0.65oz tip weight, so I could do more. I am increasing the handle overhange to match the old EZjust which move the arms out 1/8". It is not that I need gorilla pull but I like a solid feel.

I am still at the stage of matching prop diameter/pitch/lap time with allowable pack size. Right now I have a BadAss 2814 870kv motor running on a HobbyStar 5S 1600mah pack. Prop is an APCE P 10 x 6.5 ish at 9700 fixed rpm. I think this will get through the OTS pattern in 4m 40 sec. I am working on finalizing this setup.

Best,   DennisT

     Well, just for the sake of conversation, let's look at what you have. Your original post says the ship "flies fine." I would take that to mean no bad traits or major corrections needed, just the fine tuning with the prop and power plant you mention. Most of the trim adjustments mentioned will tend to make a model yaw outwards. Something to ask yourself is will inducing some yaw affect the flying qualities it already has? These airplanes don't fly as well sideways. For more "pull" what you need is a heavier rock on the end  of the string. A smallish 30 some odd ounce model is only going to pull so much. If the model turns well and grooves well, I would proceed carefully with any offset changes that will mess with a good tracking model. You will be better off just to finish the fine tuning to see what that gains you, then just get used to flying that airplane as it is.

  Type at you later,
    Dan McEntee

[Dennis Toth]

Dan,
I agree and have started to do just what you suggested. I just flew this morning with the increased overhang on the handle, same prop as yesterday (10x6.6 APCE P with hub cuff sanded off) and leadout position. Plane flew well and felt a bit better. I then changed the prop to a 9 3/4 x 6.5 cut APCE P 11 x 5.5 pitched up with square tips, horner tip angle sanded in and hub cuff removed (this saves ~5% amp draw). This prop was just a tad slower (4.78 vs. 4.68) but it felt strong. I like this prop and will just move the pitch a little to get closer to the 4.7 I prefer and add a bit bigger battery to move the CG a tad forward and give enough headroom in the pack.

I really need to get comfortable with the way this ship looks in the air. Not sure way it hits me as strange maybe the swept back rudder with the rounded sub fin gives the kind of reverse effect of the lower straight rudder/fin overhang in presentation. I have noticed this when seeing other Barnstomers fly. I think I just need to fly it more.

Best,   DennisT

[Reptoid]

     A good place to safely start with leadout position is 2 degrees aft of CG. On the Barnstormer that would be like .8". Changing the handle overhang isn't going to effect line tension at all. It will effect "control resistance" which is not the same thing.
     If you've been flying a lot of flapped ships, one without flaps will always feel much less resistant to handle movement.
     The majority feel a more forward CG is needed on electrics (some of that is likely due to the "average CG during electric flight is the same as the static CG) On a typical glow airplane the CG starts out further forward when the tank is full and doesn't reach the plan CG until it's gliding.
    The Barnstormer has a very small cross section fuselage and a short tail moment making for less side area; Side area makes line tension on a tethered airplane.
     I suggest following Paul Walkers trim procedure in the order he lists.

[Dennis Toth]

Just got back from a flying session with the Barnstormer. For this set of tests I used a larger 5S - 1800mah HobbyStar battery that added about 1oz of weight to the nose. This moved the CG about 1/4" forward which put it on the end of the LE sheeting (very close to the plans CG location). I wanted to see how it would affect the turns and glide/landing. Happily it was good for both. The level flight was a little claimer and it still turned very tight. Glide after motor shut down was smooth and easy to grease the landing. Also had a solid feel up top. I like the extra overhang on the handle and will keep it there. I think I am very close to a good setup and will just play a little with tip weight.

Best,   DennisT