Biplanes in Imac
 

Im New to Imac but i have been flying pattern for several years. With pattern biplanes actually roll better and look better through knife edge maneuvers. What i am wondering i dont see any biplanes flying in Imac, and wether there is a real legitimate reason for why you only see monoplanes in imac.
Thanks
Casey

RE: Biplanes in Imac
 

Casey,

A the local level you do not see many biplanes for various reasons. I've seen quite a few in the inviatational class flying the H9 Ultimate nd I have owned one as well before I flew IMAC so I can see how that one can be a great IMAC plane. I also owned the GP Ultimate and it was a good one for IMAC as well however it's really hard to nail one particular issue down but I think the biggest issue is the tendency for a biplane to over-rotate but a good pilot can compensate for that. Heck a good pilot can compensate for just about anything. In our region (North East) we do have one pilot that does fly an Ultimate and does very well with it. I helped him trim it and there was more trimming required for it than any other mono-wing plane I have ever done before but he let me borrow it for a weekend and I must say it flew very well.

I guess you can call me the odd person out for what I fly in IMAC, while it's a mono-wing plane you do not see many of them either. I fly a Carden Cap232 and do well with it. I also have an Extra 330L that I have used in IMAC and I will say it is cleaner in certain maneuvers but for snapping and stalling maneuvers the Cap does better.

As far as knife Edge flight in IMAC, it really does not exist to a degree, in the higher classes you do have 3/4 rolls and snaps which can place you in KE flight but for only a second.

The key to flying any plane in IMAC is to fly ONLY that plane consistently and trim it properly. I.E. do not practice with another plane, practice with the one you plan to use. It's important to get to know your plane inside and out so you can trim out it's little inconsistencies or learn to fly around them

RE: Biplanes in Imac
 

You will find after all is said and done, the true and ONLY real reason you don't see more Bi-Planes in IMAC...the're simply not popular and most flyer's when they have to get out in front of others want to "fit in" so to speak. If you bring a Bi-Plane to an IMAC event your not the "norm" and most flyer's don't like that kind of comfort level when around others...simple as that.

Personally I have never let the thoughts of others dictate to me what I want to try or do. If I were to like a Bi-Plane and wanted to fly it in IMAC then that is exactly what I'm going to do. The honest other side of the coin is that a Bi-Plane's aerodynamic characteristics are simply not the best for IMAC flying or an IMAC competitive plane.

Bi-Planes are just way too "top-heavy" and all the compensations made by the best of pilots for this condition is simply not worth the constant fight or work on the brain you'll always do to be competitive in IMAC when flying with this type of plane.

As always, good luck and have a great flying day!

RE: Biplanes in Imac
 

The only thing that kept me from getting one, PITA to setup at the field and to big for a DA 150. Every Hangar9 and Aeroworks I saw was underpowered. They fly great.

Doug Cronkite flew his H9 with the ZDZ 210 one year. It was fantastic in competition.

RE: Biplanes in Imac
 

Actually, I'm at the IMAC NATS at this moment and there are two Aeroworks Ultimates flying and doing very well. One has a DA200 in it flying Unlimited and the other is a DA170 on pipes flying Intermediate and goes like a bat out of he!! in the vertical. I witnessed (actually judged) both planes/pilots doing vertical snaps and the plane actually stopping from losing all the energy and just powering right out

I actually had the H9 version using a DA150 on Greives pipes using 9 3/4 inch headers and a 32x10 Mezjlik and go up hill like gravity was a passing fancy

RE: Biplanes in Imac
 

Yep.. I'd like another one too. Although I think I'd power it with either the DA-170 or DA-200 this go around. I'd also try to lighten it up some. It's a BIG airplane and even at 43 pounds it felt light. It WAS annoying to setup/teardown, but flying it was VERY good.

RE: Biplanes in Imac
 

Dear AZFlyerr,

I am confused by your motto:

"If your plane goes up, it WILL come down...your choice of decent is CRITICAL"

Does this mean that you must make a decent descent?

jetmanr18

RE: Biplanes in Imac
 

I agree, with the setup I had it was good but could have been better, I think I'd do the 200 since I don't think the plane would stand up for very long with the pounding a 170 can do to a plane. The 200 is smoooooootthh. We put a dime on Jason Nolls Aeroworks bipe on the cowl at the NATS the other day and it stayed right there right through the power curve. Wish I had a couple grand :D

RE: Biplanes in Imac
 

Just wonder if a 75cc edge 260 is a reasonable IMAC plane for up to intermediate level competition. I am currently flying an AW 75cc and found it is a little bit hard to slow it down to allow a constant fly style. Power is da85 with 26X8 Xoar prop.

RE: Biplanes in Imac
 

Yes it is. The prop is part of the problem for not slowing down. I'd bet with that prop it's a decent 3D plane and extremely loud, but for IMAC I'd do a good Carbon 27x10 2-blade or a 25x12 3-blade such as a PT models or Mezjlik, both can be bought from Troy Built Models.

Now I'll address the question of Intermediate. If you have not flew a contest yet, I would not start out in Intermediate, I know you did not say it that way but in my experience, most people asking this type of question are considering starting out much higher than they should. Don't let the Basic sequence fool you into thinking you are a better pilot and can handle more complex maneuvers. Doing the maneuver correctly is only part of the total score for each maneuver, Don't forget about wind correction, tracking, proper snap and spin entry, is the 45 degree line actually 45 degrees and probably the most important thing, can you fly a perfectly horizontal line at least 500 feet in length that keeps the wings perfectly level, the plane will not climb or descend or yaw in or out. You would be surprised just how many pilots cannot do that. Also, you have unknowns to deal with in every class above basic, these are sequences you cannot practice with you plane or a simulator before hand and are harder than the knowns and get even harder as the season moves on and finally is the plane properly trimmed beyond the trim tabs on the transmitter. You do not need to go through a proper trim setup but it really helps as it takes loads off of the pilot and gives you a plane that is very predictable in any type of flying, even one that flies well now can be made better. I've never seen any plane not need some time of trim work like thrust angle changes on the engine, especially if you change props for different types of flying, and also setting mixes in the radio to eliminate KE flying issues

IMAC just put out an excellent online judging tutorial. I suggest everyone go look at it. While it is geared for judges, every pilot should know what a judge is looking for so that the pilot can present each maneuver as it is supposed to be

http://training.mini-iac.com/Default.html

RE: Biplanes in Imac
 

Thanks, Bill. Will try a 27X10 CF and check out the judging tutorial.

I am flying pattern as well (current Intermediate) and have attended pattern competitions.


On the constant speed for IMAC, what is a good pace (or RPM) for 75cc plane?