400 series Battle of Britain

[ADW 123]

was wondering if you build the ME-109 with the extra wing length...

[Mitch]

Thanks for the Q's and Feedback. I just took off the cowlings and took weights here's the recap...

Bf109 -70g total, 50g plane, 20g ballast = 40% of wt is ballast.
Spitfire - 112g total, 77g plane, 35g ballast = 45% of wt is ballast.

I only held the models about 5 feet off gound and tossed them as I was in my front yard with obsticles. They both went about 20 feet.

The Bf 109 is built to scale. That is, no extra rib, but I am planning to build the 109 again as some planes seem to have had different wing tips... next model will be Afrika Korps... That one will have the extra rib and a rounded wingtip.



Don't hold your breath for that... I seem to have too much to do at home , but I appreciate your feedback... If I did not have you these models would just collect dust. I like this prototype as the color scheme is easy for me to do without paint!

Plan to go to the schoolyard tomorrow AM.

Mitch

[Wildpig]

Do you have adjustable elevators or paper trim tabs?
You might be able to adjust that glide some.

[Mitch]

Well it was raining today ... go figure... (I live in the green NW part of the country near Seattle) not heavy rain, just an annoying mist, not good for flying model plans made out of tissue paper...

So I worked on another project... trying to get a Royal Enfield to go the ton... 100mph, The blue sticker on the fork is from last years Run at Bonneville.



But back to model airplanes... trying to get these to fly with a rubber band. I think that is harder. This evening I put the Guillows rubber in and the Guillows Prop on... I think they are hopelessly underpowered... I think they would need a larger prop for any chance.



I will try a low power test flight tomorrow if the weather is nice. The planes do not have movable surfaces and I was not planning on putting trim tabs, but I have seen that before... I just am not sure how things will go. I will go to the school yard for the flight testing. I want to try to fly these with the parts supplied in the kit... well I used my own paper... okay, I will see how they go. I expect I will change out the rubber and use a larger prop.

Mitch

[Wildpig]

I think you are right about the prop and rubber size. According to Don Ross' book, a good rule of thumb is that the prop dia. should be 1/3 the wingspan.
What size prop comes with the kit?
Do the plans have a recommended rubber band size?

[Mitch]

Went for my first powered test flight yesterday afternoon with my Bf 109, it was sunny and dry. With only about 50 or so turns... the Bf109 veered sharply to the left and nosed in and as is hit the ground the tail broke off. I did not have it secured well. Decided that was it and came home and reattached tail better.

This AM went back to the schoolyard, it is overcast and the ground is wet with dew. I had the 109 and Spit today...



First up is the 109, again about 50 or so turns, the rubber has about half the length with single knots. I think I tossed the model skyward yesterday so I tossed it towards the ground. The model again veered shapley to the left and I know this is not good.

Next up is the Spitfire. Again with only about 50 or so turns tossed the model from about 4-5 feet from ground. This model did the same thing, veered sharpley to the left.



The 109 went abot 25 feet and the Spit about 30 feet. I tried to get a picture of the Spitfire in the air, but decided I will need an assistant for that...

The Prop in the kits are 7 inch. I have 9 inch props from other kits. The rubber is the grey Guillows, dobbled over and about the length of the fuselage. I figure if I can get these birds trimmed before I break them I will go with tan rubber and then try a bigger prop. But I think I need to trim these better.

Both models were wet and I decided not to fly more and not fly again in the AM dew.

Mitch

PS The sky was the same color as the Spitfires grey undersides... Jolly Good Mate

[ADW 123]

Mitch, I think i have an idea what the problem is. The torque of the motor (direction of the rotation) often causes the plane for roll left. this can be corrected a number of different ways. Right thrust is one of them. you can also add trim tabs (ailerons and rudder basically) and bend them to correct the roll. get some trim tabs, get a down thrust shim and a right thrust shim in and go out and try again. also replace that rubber with good tan rubber (i get mine from Dare design and engineering)

http://www.darehobby.com/

I also get a lot of supplies from them, including my gear winder. I would suggest looking through the web site to see what they have. they have some good stuff!

try that and let us know how it works

[Wildpig]

Keep at it , Mitch. Your airplanes sure look good out on that grass airfield.

[Mitch]

Thanks Guys... I agree with what all you say I was thinking about how the airplanes flew (more like a powered crash, or slowly falling out of the sky), but it looked like they have potential. They really did not lift off anymore after they left my hand, but that I believe is a function of power. I barely wound the rubber.

I plan to do the following, at the school yard with adequate room:

1. Test glide them again with no power but with rubber and prop installed.
2. Ballast as necessary to get good glide.
3. Have more complete field kit and shim for down thrust and thrust to right as necessary.
4. Have Trim tabs ready for field install. I plan to use paper "post-its" for ailerons

I plan to do one thing at a time, as I do not want to confuse my results. I have larger props and tan rubber but will wait to get good flights first. When I get satisfactory results I will install longer/more stands of tan rubber. But for now I need to get adequate flight path .

When I do intall longer rubber with capability for more winds I was thinking about making a small ring and thead the rubber though. That way I can unhook the prop and use my winder, then just hook the prop to the ring. Do you guys have a better idea. I plan to use a paper clip and wind it into the size ring I want then solder it so it will not open up.

If you have a better idea I am all ears. I hope to get back to the field tomorrow.

Mitch

[Wildpig]

Sounds like a good, methodical plan to me.
The ring to help with winding: I've seen a rubber o-ring used for that. I guess when you first make up your rubber motor you thread it through the 0-ring and then tie the rubber ends.
A fully wound, well lubed rubber motor is really difficult to transfer from the winder to the prop hook.
You're all over it ,dude.

[ADW 123]

its not that hard to transfer. wind it on the winder, pinch the end a couple of cm away from the winding hook and slide it off the winder. yes, you will lose a few turns but now you have a nice loop for the prop hook. I would say give it more winds. its time to just see what they do under real power. I have a habit of skipping over glide tests and what not because they do not represent what will happen in powered flight (in my opinion)

[Mitch]

Thanks... I do have expierence with building these models, but did not get them to fly when I was a kid. My thought is I built them way too heavy. So I lack experience in the getting them to fly. I still believe I should rebuild them with lighter tails and therefore overall lighter airplane. But these planes are all built now, and this is flying season. When I go back to work aboard ship I will build another batch.

But as I read this forum and Don Ross' book I realize I was really handycapped earlier as I really expected them to fly built straight from the box. One must realize these are kits made for easy assembly for novice builders, as we all get better we need to modify the build for flight.

I have to try to get these to fly the best they can and that is my purpose with these "Fly Offs" and then pick the best candidates for rebuild. Then modify my build with the expeience I gain here.

Flight conditions today... 100% overcast and clear, ground is damp... Will wait for afternoon then go to the Flight Field (K-6 school about .1 miles from house)

Stay tuned... Mitch

PS Here is some Eye Candy for you... Picture of my Gullows Luftwaffe. The Ta-152 is a kitbashed FW 190 kit

These planes are sitting on what will be my field table and winding stooge when I need that. I have a 15:1 winder

Just as I am looking at these models I realize I need a number on the Bf 109.

These are all the same scale. WS are... 109 24 inches, 190 26 inches, 152 36 inches!!!

[Steve Blanchard]

Mitch,

It sounds like you have a sound plan. I totally agree that you should take it one step at a time. If I may, I'd like to offer some help.
1. Change to the prop and rubber set up to what you want to use right now. Once you are all trimmed up and dialed in, if you change the prop and size of rubber you are back to square one.
2. Keep doing test glides. I'm sorry to say that it is not opinion but fact that ADW is incorrect to skip the glide phase. It does not represent what really happens in powered flight but that's why it's called glide test. If you have the model balanced at the correct CG point that's one thing. You can still need to adjust the decalage or incidence to get it to glide correctly. If you are far enough off then you will never get the plane to perform at it's peak level of stability. You will just fight it and never really get there.
3. Make sure you have wash out in both wing tips. Especially on low wingers.
4. The Spit is the tougher of the two so maybe you should concentrate on just the 109 for now.

I hope this information is helpful.

Steve

[Mitch]

Thanks to All,

I really aprieciate ALL coments and opinions. The great thing is I will still do what I want but I can take bits of what you all tell me. So here I go...

Flight Conditions: Mostly Cloudy, Wind NW 7, Temp 72, Hum 64%

1. I will go to feild with Bf109 and Spitfire as my quest is comparison.
2. I will keep with grey rubber and 7" prop for now, because this is a test on how the Guillow kit works, from the box.
3. I will start to use my 15:1 winder and "Pinch an Inch" of rubber to hook the prop. Great idea... I love to KISS (Keep It Simple Stupid!)
4. I will start to keep my "Field Notebook"

So I have another question... Can I put washin now? Maybe I need to steam the wings? It might be difficult. I think that should have been built into the wing during construction, and I built the wings on a flat surface. Next time I will add shims under the wingtip. I will not be disappointed if I do not get satisfactory results from flight tests as long as I learn something and can change my next build!

5. If all goes at least OKAY, I hope to add more power today.

Mitch

[ADW 123]

you might be able to if your tissue has a little shrink left. might be a little harder if dope has already been applied. I think you want washout, where you add a shim and it pushes the wing tip up. i think someone got it confused earlier in the thread...