How to instal clark y to bf-109

[karolenaz]

Hello guys,

I want to instal Clark y airfoil to guillows bf-109.

How i should instal correctly?

Like this



Or like this


Airfoil


Thank you

[Mitch]

Karolenaz,

I am no expert, but I believe the second picture looks like a good installation. I believe you can change the angle of attack of the wing with adjusting the angle of the thust bearing.

I read...(and latter discovered with my own flights) that a slight down thrust is desirerable. It changes the angle of attack of the wing to make a difference. It will get the airplane at the correct angle and allow the wing to do its job. I put 1/16 stick behind the top of my thrust bearing.

I have a question for you. Are these wing profiles from actual airplanes or model airplanes? I am nearing completion of Fredrich My Afrika Bf 109F, but you just gave me some toughts for improvents in my own next generation Bf 109G. Gernot is at early planning stages, and Freddy is not even off the assembly line yet!

Mitch

[karolenaz]

Yes Naca from real bf-109. Thank you for info

[Mitch]

OKAY THEN... that's it for Gernot... NACA wing profile, since I cut my own wing ribs in about an hour, that will be amoung the changes for Gernot...

Mitch

PS Meet Gernot, She will be the WICKED WITCH FROM THE NORTH... Dessed in BLACK...



I just need to order about $15.00 in parts from Guillows...

[karolenaz]

OKAY THEN... that's it for Gernot... NACA wing profile, since I cut my own wing ribs in about an hour, that will be amoung the changes for Gernot...

Mitch

PS Meet Gernot, She will be the WICKED WITCH FROM THE NORTH... Dessed in BLACK...



I just need to order about $15.00 in parts from Guillows...

Hello Miss Gernot Nice to meet you.

Good luck Mitch!!!

[Mitch]

THANKS,

Working on covering Freddy today... I think I will order parts for 2 more Bf109's . My last and final in this seris will be named KARL in your honor! I do not yet know the improvents at for the K model...

Good Luck with the wing...

Mitch

[Steve Blanchard]

Mitch and Karolenaz,

With regard to angle of attack, it is the angle of attack or incidence in relation to the horizontal stabilizer that comes into play with the wing. The down and side thrust adjustments are strictly related to the power phase of the flight. Not to say that the prop swinging up front doesn't have effect on the glide. Glide still needs to be achieved before powered flights are attempted. As a rule of average most low wing aircraft require approximately 3 degrees incidence in the wing when compared to the horizontal tail set at 0 degrees. Some like to put in -1 or -2 degrees in the tail and 1 degree in the wing. that makes the flight a little nose up. Not my choice but it's all about what you like to do. Either way there must be a relation of incidence from wing to tail and the CG needs to be set in it's proper location per the model. Why Clark Y air foil? If this is for rubber powered flight the tried and true best airfoils are thinner than the Guilllows plans show. Also I was told and have found to be true that the leading edge does a much more efficient job cutting into the atmosphere if it is not rounded but sanded to a more sharpened edge.

I hope this all helps you out.

Steve

[Mitch]

Steve,

I thank you very much for your knowledgeable answer that sounds much better than my GUESSTIMATE. I am very near complition of Freddrich, my Bf109F and will try to set the wing as you descibe.

I am also making a list and checking it twice for an order to Guillows for more Me 109 parts that will come together in my Model Aircraft Factory, along with my custom made parts to develop better 109's that will be coming off my assembly line.

Personally I think I will incorpoate a different wing rib profile because I cut my own ribs anyway. I think it will be a modified NACA wing rib. I want the scale look and I will make it thinner as you say for performance. I have not entered any flight contests, but I believe the plane would be judged on 3 critria.

1. Scale Apperance
2. Workmanship
3. Flight Performance

I don't know that is just what I am striving for. Lunch break is over, getting back to the factory.

MItch

[Steve Blanchard]

Mitch,

You are correct with your judging thoughts. The good thing is that wing airfoil is not really considered depending on what rules you are playing by. For FAC scale the airfoil does not get considered as a scale detail as long as you do not deviate so far from the original that it no longer looks correct. What is meant by that is if you had an aircraft that had a very thick airfoil even in comparison to a scale ship you could not thin it to 1/4 of that so it performs better. You must maintain the general integrity of the scale outlines but you do not have to match exactly. I too like to have as scale an airfoil as possible for aesthetic reasons. Other clubs or organizations are more strict but I'm not very knowledgeable about that. If you would like to try a winning airfoil for rubber power that has a nice scale look, try a Rhodes St. Genese. Anyway, at this point I am very pleased with watching your builds and seeing your ever improving flight skills!

Steve

[Mitch]

Hi Guys...

Bringing this old post up, because there was a question about my NEW airfoil for my P-51.

Wow, I can not believe it has been a year, I need to finish up my current work so I can make "Miss Gernot", the Witch from the North.

Mitch

[kittyfritters]

FAC rules do not count off for scale points if you decide to use a flat bottomed airfoil when the real airplane did not have one. What you cannot do is use an undercambered airfoil when the real airplane did not have one. There are many rubber powered scale models that do very well with a modified Clark-Y (Sectioned horizontally with a flat bottom.) It's not an optimal airfoil in any category, but a good, reliable all around compromise.