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Ultimate setup

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Old 11-03-2008, 11:10 AM
  #1
Zort86
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Default Ultimate setup

Hello everyone, I have a few questions.

I am thinking about getting in to IMAC Basic next year. I am currently flying a 29% Ultimate that I wanted to setup for competition.

So far what I have read is that it may take a bit more time setting up correctly, due to it being a biplane, but it should be a competitor.
I have the basic trimming sheet.

My question is is there, or what are the differences in setting up a bi-plane compared to a mono plane for IMAC?

How would you sugest I go about getting this setup and trimmed out to get it ready for practice and competing?

My setup is I have the bottom wing and the horizontal stab set to 0 degrees and the top wing at -1degrees incidence.
The engine has the stock offset.


Thanks in advance for the help.
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Old 11-10-2008, 05:40 PM
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Danny Baker
 
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Default RE: Ultimate setup

Mr. Zort: The basic answer is for you to set up the plane as if it were a mono plane. Since you are flying in Basic this coming year all you have to do is set er' up to fly the geometry of the manuever. On the IMAC web site is Peter Goldsmith's trimming guide for any plane (bi-plane or mono-plane). I'll not going to repeat it here since it's several pages of information on how to set up a plane to fly IMAC. I'd print that puppy out and take it to the field. Just a note about the trimming guide, it's designed to follow it by the numbers. Please don't do step 4 until you have completed steps 1, 2, and 3 IN THAT ORDER. It really does matter.
The biggest learning curve that new IMAC pilots go through is trimming a plane out to fly good. This stuff is about 4 times easier to do with a well trimmed out plane. Don't be satisfied with your thrust until the plane is going straight up "hands off". Keep spending the time adding washers for L, R, U, and Down thrust until she tracks good on the upline. Also set up the transmitter so that it takes full stick deflection of the gimbles to fly the sequence. Most new pilots only move the gimbles 1/4" L, R, U, or Down to fly the plane. This in incorrect. You should move the rudder gimble "hard over" while flying, move the airleron gimble "hard over" to do the rolls, move the elevator gimble "into your belly button" to pull out of your hammers and humpties. With these gimble movements coupled with these throws, your Ultimate will be a SMOOTH flyer and not a plane that is "all over the sky" trying to keep er' straight.
Any spacific questions, just ask. I've been flying in the Unlimited Class for over 8 years, and have had several bi-planes, all Ultimates.
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Old 11-11-2008, 08:18 AM
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Default RE: Ultimate setup

Danny,
Thanks for the great advise. I have read the instruction you have talked about and printed them out for my next trip to the field to start trimming it out.
My biggest question was if there was anything different from the trimming sequence between a mono-wing to a bi-wing airplane, and you have answered that for me.

I am looking forward to getting out there and competing. I am going to spend the next few months trimming and practicing to get ready for next year.

Thanks again, hope to see you out there next year.
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Old 11-11-2008, 09:08 PM
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Default RE: Ultimate setup

I have 3 Ultimate’s and it does take a little bit of differences in setting up Bipes since you have 2 wings and 4 ailerons to check to see that all of them are going up and down the same amount. Same as a mono is to make sure it has the correct up thrust, right thrust, and CG is the same for any bird. Most Ultimate need and also are designed with up thrust in the tail and different kits will carry different amounts on each wing that need to be checked. The rest is fly it and adjust as needed if your also run mixes as with any bird….and need it talk at you
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Old 11-11-2008, 09:20 PM
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Default RE: Ultimate setup

krayzc-RCU


I have a WH Ultimate Bipe. They want you to run -1* in the top wing 0* on stab and bottom wing. What do you run on your bipes?
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Old 11-11-2008, 09:58 PM
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Default RE: Ultimate setup

Soarrich I do what the maker says from here I do the regular adjusting to suit a true tracking bird.

My Bob Godrey Ultmate carrys O on the bottom and the top wing is set correct by the straps that hold the top wing

The Hanger 9 Ultimate carrries -1 on the top and O on the bottom

Both Ultimates carry 2 degrees of postive thrust on the stabs ( the front of the stab is raised)
Both carry about 2 degrees of up thrust for true hands off up lines

Both carry about 2.5 to 3.25 of right thrust
Both planes have 4 servoes on the ailerons and I have to 8-32 bolts and radio trim numbers to have all four ailerons moving at the same degree on both up and down ailerons on all rates low and med and 3d or how ever you set your up.

10-12 on my low rates elevator
20 on low rates ailerons
20-25 low rate rudder

I do not fly a med rates on elevator only rudder and ailerons until i figuure which one fits my needs....
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Old 11-11-2008, 11:13 PM
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Default RE: Ultimate setup

Thanks
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Old 11-11-2008, 11:23 PM
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Default RE: Ultimate setup

Quote:
ORIGINAL: Danny Baker
Also set up the transmitter so that it takes full stick deflection of the gimbles to fly the sequence. Most new pilots only move the gimbles 1/4" L, R, U, or Down to fly the plane. This in incorrect. You should move the rudder gimble "hard over" while flying, move the airleron gimble "hard over" to do the rolls, move the elevator gimble "into your belly button" to pull out of your hammers and humpties. With these gimble movements coupled with these throws, your Ultimate will be a SMOOTH flyer and not a plane that is "all over the sky" trying to keep er' straight.
OMG, Danny thanks for this tip! I had no idea... I imagine doing this will help tremendously. Right now I've got it set up so a roll only takes 1/4 throw, which allows for lots of error when adding in elevator.

I can't wait to try it!
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Old 11-11-2008, 11:27 PM
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Default RE: Ultimate setup

Danny,

What is your average throws to accomplish this on the surfaces? Seem very kewl when i think about it until i come to snaps....
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Old 11-12-2008, 01:50 AM
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Default RE: Ultimate setup

The neg. incidence in the top is so the bottom wing stalls before the top one on landings or spin entries. This turns the plane into a high wing trainer just before the moment of full stall. This feature remains the same when it's inverted, the top wing (now located as the lowest wing) will now have + 1 degrees in it, allowing it to stall first and leave you flying off the highest wing just before full stall. This is a safety feature for full scale and for sport pilots. However this feature may not be favorable for all attitudes of the plane. Kitting companies put this in the design just incase the builder is slighty of in the construction of the plane. First flights are protected. First landings are protected from tip stall also. For Imac Basic I'd suggest following this, and it won't hurt your flight. As you move up in class, you'll want to have both wings at zero zero.
My Carden Cap flew with 1.0 positive inc. in the stabs. I had three of these, they all needed +1.0 in the stab to get the elevators to line up with the stabs once it's trimmed out. Don't put this in your bipe just because you read it here. Fly and see where the elevators are resting after you like your thrust (engine thrust) and CG. Then move the stabs to line up with the elevators if need.
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Old 11-12-2008, 02:14 AM
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Default RE: Ultimate setup

Mr. Krayzc: I'm an IMAC pilot in the Unlimited class, and this thread is in the IMAC section. So my answers will be favoring set-up for IMAC flying. I set up my plane to the snaps at full transmitter stick deflection of the gimbles on all three axis (airl, ele, rud). Every snap is done the same on the transmitter by way of full stick deflection. I then play with the length of the servo arm and length of the airleron arm so I get the desired airleron throw while the ATV on the transmitter is at 140 % for airlerons. This way I'm getting the best mechanical advantage that the servo has to offer, less gear wear, less case wear, less battery usage, less linkage slop, less chance of flutter, I could go on and on ....... I set this up to give the desired roll rate for the snap. I DON'T roll the airplane at full stick deflection, I roll the plane at partial stick deflection. I know, I know, this contradicts what I posted. However in the Unlimited class we have more snaps than rolls, and snaps are harder than rolls, so I better let the transmitter help me with my snaps. In some cases we snap the airplane 17.5 times in one four minute flight. To get the feel I want when I do a point roll (the airlerons will be too sensitive for partial stick commands set up this way) I add expo until I get the "feel" I want at smaller stick inputs. This way I don't have to hit a rate switch for snaps. All my sequence flying is done on the same rate as far as airlerons are concerned. The elevator and rudder only have about 10-12 degrees of travel in them each way. This keeps the tail "quiet" while flying, and helps to hold the tail behind the nose.
I change models in my transmitter to fly 3D. It's impossible to fly IMAC and 3D on the same model memory at the unlimited level. I have two model memory's stored for each plane. One is call Yak-IMAC and one it called Yak-3D. One can't fly 3D with 10-12 degrees of tail throw. Conversely, one can't fly IMAC with 40 degrees of tail throw.
Hope this helps,
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Old 11-12-2008, 09:50 AM
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Default RE: Ultimate setup

Danny,

That helps a lot. I do not fly each year in IMAC but am looking to start in the coming years with 2 contest that are held here in NC. I fly 2-3 rates myself one being a 3d rate and the other being my low rates of 8-12 degrees on the elevator and 20-25 ail, and 20-25 rudder. On my flight mode 3 i am usually trying to find a good mix for the rudder and ailerons for snaps and stall turns. If the bird and do it all on low rates I work with that if not i go to flight mode 2 for hammer heads and such. I do my rolls also by just moving my stick as I watch how much the plane is rolling. I have heard were some guys do a roller this way i do not and just wondered there on your needs....
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Old 11-12-2008, 01:29 PM
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Danny Baker
 
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Default RE: Ultimate setup

I use three flight modes for my IMAC flying. One is for most all flying as described above, another is for hammers and rollers where the rudder has more throw and the airlerons are slowed down so the plane doesn't start rolling to fast in the roller (we have "one roll" rollers all the time.) The third is for spins where the elevator has some more throw to get a good stall break. In reading your throws for your IMAC style flying, may I suggest less rudder throw for snaps. You should only be using 10-15 degrees of rudder. Any more and the snap wants to over rotate all by itself after letting off the sticks. A lot less rudder throw, and the snap will stop when YOU tell it too.
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Old 11-12-2008, 03:47 PM
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Default RE: Ultimate setup

Thx Danny i will correct those rudder throws on my low rates......
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