da Rock

Prop tips produce contrails depending on the weather. Notice the contrails don't go anywhere? They hang right where they are generated as the plane taxiis.

flyncajun

Hi Vince

Doug has not designed an airplane ,so he would no be invited to the conclave Well he could moderate it

Over the years I have designed Many planes, some with right thrust ,some with downthrust, some with both some with too much of each
The Patriot has .25 right only, untill the 3D it went to .5 down The quest had no thrust at all. The SHinden had .25 down and .5 right The Valiant down thrust was over adjusted because of the small wings. but it worked with adjustment in other areas.
Notes are kept on each of these models for testing and adjustment. When you contact me on my designs, I give you updated and Specific instructons on how to trim it , set up the Snaps,spins ECT. I know What I`m talking about. I created them. and I work hard to understand and make it better.

There is not much difference in other designs other than style. the Brave guys who wander off the reservation pay the price for it Like Chips bipe, Or My Shark Bipe LOL 'the price is second guessing and home work. Putting the WIng on top the Canopy was laughed at by many guys well except Jason He loved it! ,,But ,Now it seems like the thing to DO

This is where learning, testing , and experience is payed off. I learned more about Bipe design from building the Shark Bipe adjusting the wings over 25 times it was not very successfull, But, after25 wing adjustments on a non adjustable wing LOL I found the correction. This is the Price to Pay to be a designer willing to take chances andnot Copy every one else. YOU learn from Failure and Success. But you remember the Failure and learn the most from it.

This is Why I can trim other designs without even flying them, or instruct someone on how to set the Canilizer without even even using one, even the Designer of the Canilizer[X(] Experience and Common sense.
Never once have I had to factor in the Spiral slip Steam I factor in my notes on where something is crooked causing the problem. and in the end it`s simple cause and effect.
we sometimes attack the problem from the wrong angle ,that problem is caused by another miss alignment, find the Genesis, fix more than one problem.

I dare say very few people ever measure their downthrust or even know how to,or, if it`s important. very few guys can even accurately measure their CG.

Every thing that contributes to the flying of the airplane contributes to the good and bad qualities. how to adjust out the bad qualities, is where the knowlege is.
How some body with no design experience can look at a airplane and say why it was designed as such is just Hypervily.
The Guys that aurgue with me about these things Secretly PM Me for advise on setting their airplanes up or solving a trim problem >

Bryan

OhD

Doug,

The following, I don't know what to call it,:

"Spiral Slip steam ", Has no Proof ,and -Here`s the Spoof

is not a sentence and has no context and as a result I believe you are wasting your time. In fact what is spiral slip steam? Somebody using steam engines now?

Jim O

Ryan Smith

My Feedback: (25)

Something about a boundary layer, perhaps?

JRgraham

My Feedback: (1)

Good stuff, cajun!

flyncajun

I agree Jim I`m waisting my time

Lets here your trim method

Bryan

DWNUNDR

Bryan,All you have to do is take a look back in history. All of the pioneers always had those critics who would pull their ideas apart and accuse them of being crazy. Then all of a sudden those crazy pioneers work comes to life and shuts down all the critics who then turn coat and jump aboard saying thay always knew it would work. I use your methods for trimming and have found great success. Keep up the good work mate.

Doug Cronkhite

My Feedback: (34)

Bryan, people only waste their time if they're unwilling to learn. This started out as a discussion about Chip's new design, which a few people who have aerodynamics education believe will have wing interference issues, which you then turned into an evangelistic discussion on your trimming methods. I won't deny your trimming methods on existing designs work, because they clearly do. But your absolutely unflinching disregard of basic aerodynamic science based upon your experiences (the "don't confuse me with fact, I know what I know" mentality) suggests you got there by repetition and blind luck. It doesn't mean your end results are wrong, more likely you just took a very inefficient means of reaching the end solution.

By the way, what is 'Hypervily'? I can't find that word in a dictionary, anywhere.

MTK

I probably shouldn't say anything, BUT.......As far as wings interfering with one another, I don't agree. Like I said earlier, speed just isn't there. But we'll see.... What basic "aerodynamic science" are you referring to? I'm not an aerodynamicist neither by profession nor education but so what? It's been a hobby of mine for decades. The problem with ANY education is that it implies to the "educated" that they knowa subject. That sometimes can interfere with actual learning. Consider the amount of formal education the best engineer mankind has known had.....Dare it be said he had NADA?

"Hypervily" ...the name of a new design possibly. Sounds pretty kool to me

Give the guy a chance....he's been the first to tellallhe's no writer. If I were to hazard a guess I'd say Bryan meant Hyperbole, another fine (and most appropriate) model plane name...

Bob Pastorello

My Feedback: (198)

I'd enjoy reading the aerodynamic stuff if it was pertinent to the thread topic.
Experience produces beliefs, usually, and education produces knowledge to be applied. So it's reasonable to assume that beliefs will frequently not match (or concur) with experiences based on applied education.
I'll look forward to hearing more about a bipe design with wings spaced less than an average chord-length. Should add to the body of experience and allow new ways to apply what has been learned. Great stuff, guys!!!

Doug Cronkhite

My Feedback: (34)

Agreed Bob. When Chip showed the pics, I contacted him with my thoughts, and he said he thought it would work. I'm looking forward to hearing his results. That was really the end of it.

flyncajun

HYPERBOLE ,Just another word I learned to spell LOL Thanks Matt , I might use it on a airplane in your Honor LOL

Doug can`t you see I`m being a little absured? don`t you think I know Science is real? I just don`t waller in it. I look for hard facts.
I am a Volvo Mechanic, My Job is to fix things, I`m the top Tech at our dealer, and have many years of class and advanced learning in the field. I`m one of the Highest paid techs in the Baton Rouge area, Why?
Because when I say it`s fixed I have to be 100% sure it is fixed I can`t just quote from the textbooks. and I`m judged on performance, You also must understand, I work on very complicated systems I`m not a Dumb Ass

Even though I can`t Write worth a hoot, I speak very well. and if you could get pass my spelling you would learn something.
I don`t troll the Aero sites or research google to argue my points with textbook words,
I`m not on any Mission other than cutting the BS about using words and terms , or blaming things that don`t apply to Model airplanes or our designs. Or, blaming un seen forces on things I can prove don`t exist on our models. However,Because you write well people my be persuaded with your big words

I wasted years chasing the "STANDARD " set up of known trimming knowledge. I had to debunk most of it .I`m only trying to give solid advise ,the problem is, the good writers sound smarter LOL
Who on this disscussion has a education in this subject? None! they would blow us away with words and terms. I asked you to tell me What the Spiral slip stream Caused you still have not told me, Because there is no such thing ,and you know I can debunk it.

Please don`t think this is personal I enjoy the debate.
And don`t offend easily. I love the hobby. Like Matt, this is something I have been pursuing since Childhood! it consumes me. I Like the discussion , I have read Jim Oddino, Dean Pappas and Don Low when they were in my favorite mags. as far back as I remember ,I respect these guys for sharing what they know,this started me on the trail I`m on today.
I marveled at what they knew about the Hobby and now I`m paying them back by sharing what I know to others, I stand on thier shoulders.

I get very little credit for many advances in the Pattern Design world Because ,I don`t win the Nat`s, or make the Team. But the guys on Teams the world over come to me for advise in many areas. you never hear me crowing about it. Would you be surprised to know that CPLR`s airplane built by Oxai is based on my set up. I never flew his Plane, I just used my knowledge to help a guy who bought one ,in turn He sent the setup to the designer because he thought it was revolutionary. Have you noticed the canilizer went from a negative setup to a positive setup?
Have you noticed the change in thrust ,,Most have not,I did now everybody is going to do it

Please don`t confuse my ability to design and trim airplanes with my ability to fly them or understand whats going on I know what makes an airplane fly and I know the basics of flight and understand enough to know what not to speak about. They told the Wright brothers, "That thing will never fly" don`t you know if God wanted man to fly he would have givin them wings LOL.



You made a statement, I challenged you to back it up ,simple as that. I`m hanging it all out, and you want me to show you the math of my knowledge.
Most of my questions are bait! the reply shows me what others know

Modelers, Just want to know how to fix ill flying airplanes, Thats What I can do. You can write,,

Doug are you a Aero Engineer?
have you ever designed anything?

Bob good to see you back

Bryan

bjr_93tz

Would anyone care to theorise why it's the bottom of the left stab that gets the oil residue on my plane when the exhaust exits on the centerline?

The couple of degrees of right thrust explains a bit of it but it isn't the whole story. I wouldn't say the airflow actually spirals around the fuse, but I'd bet my bottom dollar the left stab is seeing air coming from a slightly different angle than what the right one sees. (or maybe I just fly right wing low with left rudder trim to keep it straight?)

Anyway I stand by my original comments that I think it looks good, and if it doesn't fly well (?), then F3A bipes shall forever more have their wings spaced further apart

flyncajun

Right thrust
Bryan

RC_Pattern_Flyer

My Feedback: (1)

I get no oil residue from my pletty.

Bryan maybe be right, but I would look closely at the type of power system you are using.

Chuck

MTK

Nah!! Your stinger isn't long enough.....Ahem...that can be said for most of us, BUT don't think anyone cares.LOL

klhoard

My Feedback: (10)

.
Coriolis Effect. Our planes "up" here get oil residue on the right stab . .
.

OhD

One of the reasons I quit flying glow engines was I always had grimy left shoes.

Jim O

TonyF

My Feedback: (92)

Here is some interesting reading. Particularly the one written by Michael Selig. He modeled a Funtana 90 to explore 3D and Hovering type maneuvers. Please note the references in all three to that silly, non-existent spiral slipstream.

n233w

Cool Giant Scale Cap 232 photo. You can see something spiraling back away from the model after a brief skip on the pond's surface.

Bill P.

apereira

That is one of the best pictures I've seen this year for sure, very nice!!

Doug Cronkhite

My Feedback: (34)

I studied aerodynamics in college, but I am not an aerodynamics engineer. I design games for a living. Yes, I've designed a few airplanes. I designed and flew an electric F3A airplane back in 1999 using an Aveox 1415-2Y motor, and 27 NiCd cells, and was told not to bother since E-Power will never work. I've designed and built a few IMAC airplanes over the years, and currently have a 40% MXS-RH in CAD that I'm working on.

So yes, I've designed airplanes as well. None of which actually matters. The science involved doesn't change based upon what you've built unless of course it proves or disproves theory. Michael Selig hasn't designed any F3A airplanes. George Hicks hasn't designed any F3A airplanes although he DID design the airplane that won the 1st E-TOC, and both happen to be well respected, working, aerodynamics engineers.

Back in 1944 I think, the NACA demonstrated that spiral slipstream was real by measuring pressure distribution on the tail surfaces of a P-40. They showed that at low speed, there were forces pushing UPWARD from the bottom of the left horizontal stab, and DOWNWARD on the top of the right horizontal stab, and that as speed increased, this pressure was reduced, and deduced that this was a result of spiraling airflow. Spiral airflow is also the reason why today's model turbine engines and older ducted fan propulsion systems have fixed stators internally to straighten the airflow.

Understand something Bryan. I never once called you a dumb ass, and never once said you weren't a successful aircraft designer. Your trimming methods work. But that isn't what this discussion was about. Myself, and others commented on a specific design feature on Chip's new airplane, and you decided to make this about spiral slipstream instead.

nonstoprc

My Feedback: (90)

Check out [link=http://www.pond5.com/stock-footage/142398/rotating-boat-motor-propeller-prop-as-it-moves-through-crystal-clear-water-un.html]this video[/link].

AmericanSpectre505

Well this Topic got all hijacked to he!! and back. Anymore photo's of Chips concept to post? Am I to understand Oxai may produce it or is that an assumption?

bholsten

toddblose

My Feedback: (10)

Bill, Oxiai is making the plane not sure when it will be ready