I would like to ask. Why everybody is willing to use heavy/more expensive engine+tune pipe in heavy airframe and not to get light airframe and go with any good .40? I think it's better, our models have from 26 oz. 51" to 48 oz. 61" empty weight! With .40FX you can hover at 1/2 throttle all day long.
Thanks for input.

My grand pappy always told me "there's no replacement for cubic displacement"

Actually, I have put all of my planes on diets. I agree, the lighter you can get the model, safely, the less money you will spend on the power.

Why do my posts get deleted, but SPAM like this is allowed?

totally agree, radfly! nothing like a cheap advertisement.

Why buy a Camaro when a VW Bug is lighter and cheaper?

Why ride a Harley when a Yama-zuki 100 will get you where you're going?

There is some advantage to a heavier plane. One school of thought says keep your planes light, and you can use a smaller engine thus saving even more weight. Another says additional weight can be overcome with more power, therefore providing better wind characteristics.

I say build a plane light. So you can bolt on a bigger, heavier motor, thus giving you tons of power. So far I love this concept, and I don't think I am going to change.

Look at the TOC pilots flying their 40%. Sure a DA-140 will get the job done. but a DA-150 will do it so much easier.

But we still have something like a wing loading?
I like the concept of F1 cars, strong engine+light airframe.

modest-master>>>Please explain to me. (post # 11) I would like to ask. Why everybody is willing to use heavy/more expensive engine+tuned pipe in heavy airframe and not to get light airframe and go with any good .40? I think it's better, our models have from 26 oz. 51" to 48 oz. 61" empty weight! With .40FX you can hover at 1/2 throttle.

I think everyone was pretty much ignoring your spam replies about your planes to every question that might have a remote tie in

Sorry but your planes are way too expensive. And I regulary buy Kyosho planes which are outragious (3 of my last 4). My suggestion is buy a container of these planes so you can cut your price in half and still make a 100% margin. Then you will have a bunch flying out there and people talking about them.

Given the choice of your plane (and several look very nice), the Madness or the Kyosho Flip - I went with the Flip - just too much risk for the higher price.

Just my 2 cents since you asked....

No longer support RCU

That is such a misconception, actually lighter airplanes fly better in the wind than do heavy ones. Heavy ones just appear to fly better. It basically boils down to F=ma......once the wind accelerates your model it takes more force to stop that acceleration, a lighter model will take less.

A lighter model will appear to be getting bounced around, but actually it is maintaining its heading and altitude with almost no correction, while a heavier model will take some effort to maintain a constant heading and altitude, although appearing to be flying better the pilot is working harder to accomplish the same thing as the pilot of the lighter plane.

Uh.....What?

can773 is spot on target -
A heavy model is of NO use ---in a powered model -
In a speed glider -yes - as it uses inertia to gain speed in dives.
A powered aerobat simply can NOT be built too lighty- Too flimsy and a poor aerobatic setup - - yes
- but if power loading is extreme and weight loading is extremely low - you have the best possible setup.
Windy weather flying - (20mph) with this type setup looks far smoother as speed can be varied as desired.
Been there dun it -as have many others --
Building really light with lots of power takes more work -

I think I must have missed the same thing you did....
I have yet to see a light, under-powered plane...fly in winds as well as a heavier plane with more power...but maybe I missed something along the way....

Somewhere along the way....I heard that in power planes....the keyword was "Power"....but I could be mistaken about that too. ( ??? power-loading ??? )

With todays advances in composites it would be very east to build a 130 inch Extra in the 16 pound range, it would be expensive but fairly easy. At that weight a ZDZ-60 would deliver unlimited performance but not one TOC pilot does it and they have the money. Light planes do fly better, but there is such a thing as too light. The best wing loading depends on the size and shape of a specific plane, there is no single number. Dick, I have been a glider pilot for a long time, ballast is used to help the glider maintain its speed through maneuvers and penetrate wind gusts better {inertia is not acceleration [an object at rest tends to stay at rest and a object in motion tends to stay in motion unless acted upon by an outside force]}. I does help the glider accelerate because of the additional weights ability to overcome airframe drag, but thats not the reason its done. If a 5 pound 40 size Extra flew better than a 35 pound 40% thats what the pro's would be using, after all they are there to win. This is however just my opinion and everyone is entitled to there own.

Lighter is better in the air. I can't believe anything else. I do, however put lots of power. If I can balance it without lead or other dead weight, I consider that to be "permission" to do so. I love the "Diabolic", but not for $339.00. Let's get'er to $259.00 or $279.00 and we'll talk! I would probably put a 61 or 91 2 stroke though. Any objections guys?

Outcast -- you forgot about drag- that is why mucho power is needed
My Bucker is VERY light - but it is like flying a parachute --till you add lotsa power - then the light weight REALLY pays -
And I have built for the TOC- weight is still the elusive element.

Outcast, you're also talking about a 16 pound plane. I'm talking 40 - 60 size. Don't get me wrong, I'm not saying a heavier plane is better. I'm just saying that in SOME cases, there is SOME advantage to having a little weight behind you. You say that a heavier plane only "appears" to fly better. Well isn't appearance what it's all about?

You've obviously never built a 40% aircraft then. The LIGHTEST we've seen the all composite 40% class aircraft fully equipped is around 31 pounds from FiberClassics. I could see a bare airframe getting down to 16 pounds, but then you need to add everything to make it fly.

Let's see..

Airframe - 16 pounds
Engine - 10 pounds including mufflers, ingnition
Radio - 3.5 pounds (15 servos, 2 receivers, 2 Rx batteries, 1 ignition battery)
Misc - 2.5 pounds (wheels, linkages, servo extensions, glues used in construction, general hardware)

Looks like about 32 pounds here..

Doug Cronkhite
Team JR

No longer support RCU

In 40 to 60 sized models I find lightness and power are best (less than 20 oz/ft^2 is real nice).

I have no experience with the big Extras,etc. but you can tell wing loading does no scale linearly (I think it goes by ^3). A 28 oz/ft^2 Extra just seem to float in whereas a simularly loaded 40 sized model seems to drop in. My heavy 89" Dynaflight Decathlon (32 to 34 oz/ft^2) flies nicely with the correct CG.

Good discussion except for the SPAM stuff!

marcus

MikeB, I didn't say a heavier plane appears to fly better, can773 did. Dick I didn't forget about drag, And with a Buker {yugman or yugmiester?} you have far more drag than the typical TOC. My point was with any size plane there is a point where the wing loading will become too light. You may be able to do a loop in 5 feet but the airframe will no longer tumble with authority. The 1st post refers to heavier engines in heavier airframes, perhaps the misunderstanding here is the definition of "heavier".

Well- You just can't build one that is too light -I have tried and even my new 19 oz ft wing loading model cuts thru wind - tumbles etc easily - the low weight will show up on some simple falling maneuvers -where falling rocks do better -but for all but high inertia stuff - lighter is better.as long as you keep the power up.

THere is also the consequences of Reynolds Number. This is the relationship of the size of the wing to air molecules. Simply put, a smaller wing will produce less lift per a given area than a large wing. See http://www.nd.edu/~mav/research.htm for a simple explaination.

Yes - because of RN- we really can't build "too light".
Most kits on the market for under 1000 sq in models are simply flying stones- exception being the better 3D models which are built like old Wakefield rubber band models.
really desireable wing loadings of these would be under 25 oz sq ft
on the smaller ones - down to 14 oz is still not too light.
The guys have to fly em fast to keep em from stalling/snapping.

Modest-master, I have a Diablotin Super bought from you. I was willing to pay for a extreme light airplane. I'm flying it with a old HP.40, and this is a very nice combo. This is the funnest flying airplane I've had bar none. I would love to have a DiablotinXL, but I will not buy an other airplane from you. In my dealings with you I felt your business was not operated in a very professional manner. Your unsolicited postings here make it seem even less professional.