Tips & Advice

F3C Basic Settings

F3C Basic Settings FAQ
By Gordie Meade

Compiled by Erich Freymann from the “F3C Basic Settings” Thread on RunRyder.com

Q: Do most F3C flyers hover at 3/4 stick or 1/2 stick?

A: Most of the flyers I know hover at half stick and set the radio for a VERY linear feel up and down. In the new 14MZ I am using an “expo1” curve with just enough negative pitch to glue the model to the ground in the wind. I adjust the expo to get a “soft” feel right around center but enough available pitch to still hang on in the wind.

Q: What RPM is used for hovering?

A: RPM is blade dependent. When I was using the High Products TZ91s, I hovered around 1390-1420. With the RotorTech 720s I currently use, I’m at 1450-1480.

Q: What RPM is used for FFF?

A: In FFF I run 1950rpm on a 7.9 gear ratio. It’s very calm and quiet in a hover but goes like stink upstairs and is pretty fuel efficient.

Q: Do most contest pilots used different set ups for windy conditions or just compensate with skill?

A: I do have windy weather adjustments. I can steepen my hover pitch curve at both ends to make collective a little more sensitive (on a rotary knob) and I have a dual rate set up (on a switch) only in hover condition and fly with it on in the calm and off in the wind to give me about 10% more cyclic, which is still VERY soft.
Most 3Ders that hovered my contest model, would think the radio quit .

Q: Are you saying as far as your pitch curve goes you set the curve up mechanically VERY linear with your hover pitch at half stick? So what are you top and bottom pitches on average? and tell me the advantages of this set up verses max top and bottom with 0 deg at center and then just dial it out for the contest.

A: My model is mechanically centered on the center of the actual pitch range I am using. I figure out what max pitches I need and then figure the center and set that mechanically. For the current schedules I have -8 to +12 degrees so mechanically I am centered at +2 degrees. I use my computer radio to put hover at midstick. When I go into idle up, I go to a linear pitch curve centered on 2 degrees. 3D guys usually say they want to KNOW where zero pitch is. I don’t give a rat’s butt where zero is as I’m going to fly the maneuver SO many times, I will learn where I need to go to make the maneuver look good and be correct.
For the 2006 schedules we have several inverted maneuvers that will require a more 3D pitch curve, for me -10 to +12 so I will redo everything to center on +1 degree and use the radio to get what I need where I need it.
In hover (normal mode) right now I have -3 to +13 (I’m overdriving the top here to get a straight line, I NEVER get to +13 degrees but it makes the pitch curve “feel” linear) but I think Wayne uses just enough negative pitch to make sure the model stays on the ground when hovering in the wind. In my general idle up I have -8 to +10 and in hold -8 to +12.

Q: So, do you have any problems adjusting when you go from a F3C setup to a 3D setup? I learned to hover at 1/2 stick and it took me quite a while to get used to hovering at 3/4 stick.

A:LOL, Actually no! My 3D models hover at 5/8s stick, above half but not far enough above to make me uncomfortable. In idle up, it is -10 to +10 and I get a slight drop if I switch into idle up while in hover but it’s minor and usually I’m climbing a little anyway so it is barely noticeable. I frequently switch into idle up sitting on the ground for some type of 3D style take off. I just cannot make myself hover at 3/4 stick and really don’t feel the need to. It makes sense to do it if you’re a pure 3D flyer, but I am not.
My F3C models are always climbing away from the box at 3/4 throttle when I click into idle up so you never see any change in the model, it just revs up and hauls butt. The hardest thing I ever did was switch from flying with my thumbs to my fingers and thumbs. It took me about a year to really be comfortable.

Q: I know it is a very long and drawn out answer but let’s start from the first step on how to set up and balance an FAI heli.

A: You’re talking about a book here but maybe we can start a “Reader’s Digest” version of getting an F3C model going.
1. Decide which model you are going to build and if it has options, like multiple heads or gear ratios, decide which you want and need. In my case, I run the YS 91 so select a 7.91 gear ratio, and I use the MA Tempest FAI rotor head because it is SO adjustable and has good characteristics in hover.
2. Build the model. Make it straight and make it to fly, not crash. I Loctite all bearings to the shafts and blocks. It’s a pain in the tail to take apart BUT I never have a bearing spinning in the blocks and making radio noise and the model lasts nearly forever. Take your time and align and balance EVERYTHING. If the fan is not on the motor with run out less than .001, it will never be smooth in a hover. If the motor and clutch are not aligned with each other and the main gearing, the model will never be smooth. Take your time and get it RIGHT. A screw up here means the model will never be as good as it can be.
3. Install the radio and here’s where the fun begins.
Set the radio for midstick everything. As you install linkages make sure all servo arms are at 90 degrees to the rods. Put all sliding things in the middle of their travel and adjust linkages until it is mechanically perfect, all bell cranks level, all mixers level, etc.
If any of these aren’t done correctly, you’re wasting your time from here on.

Okay, we have the model built, everything is balanced and aligned, radio is installed and, at midstick, everything is in the center of the travel, mixers are level and all linkages are at 90 degrees. Decide what the maximum pitch ranges you will ever need are. For the current schedules I use -8 to +12 so I’ll use that here. The process is the same no matter what pitch range you are using. -10 to +10 is the same, middle is zero. Calculate the center of the pitch range you are using: i.e. -8 to +12 is 20 degrees so cut that in half, 10 degrees so add 10 to -8 and you get +2 so my center pitch should be +2 degrees so I have 10 above and 10 below. Adjust the pitch arms to give yourself +2 degrees at the blades, servos still at 90 degrees, mixers still level, still at midstick.
Maker sure your pitch ATVs (AFRs) are at least 100%. Go to full positive stick and see how much pitch you actually have. If you have 15 degrees, you need to use a smaller servo arm on an mCCPM model or cut the swash mix pitch in an eCCPM model, if it is only +9 use a longer arm or more swash mix, and again make sure everything is 90 degrees and level at mid stick. Check low end pitch and make sure you are getting -8 (or whatever) if there are very minor differences, you can add or subtract ATVs but it should be only a very small %, 3-5% at the most. When you are satisfied, go to your hover pitch curve in the radio and raise the curve so that midstick (if you hover at midstick) is 4- 4 1/2 degrees (you will change this to get the model to hover at the selected rpm at exactly midstick). I make a straight line from full pitch to hover to low stick, usually something like -3, 4.5, 12 at low, mid, high. I always make sure I have a little negative pitch so I can “glue” the model to the ground when hovering in the wind. I may slightly flatten the middle of the curve to make the model less touchy right around center. I don’t worry if I have excessively high pitch, I may overdrive to +13-14 to get the “feel” I want in hover but I will NEVER go to full pitch/power in normal so I don’t even worry about being over pitched. I then set my idle up pitch curves -8 to +10 (or whatever the motor will pull) in a straight line. The centers of these two curves (normal and idle up) don’t match since normal is at +4 degrees at midstick and idle up is +2 at midstick but the motor is only turning 1450 in hover and 1950 in idle up so the change isn’t as bad as it sounds and I usually only pull into idle up as I leave the box and am powering up and climbing. All that happens on my model when I pull the idle up switch is that the motor revs up and the model hauls butt. I set my throttle hold curve as a straight line from -8 to +12. Now I rarely ever go to -8, come down usually around -3 to -4, but use the -8 if I am going to overshoot the spot and can go to -2 or even 0 if I need to stretch to the spot.

You have all the pitch curves set to match what you think the motor will pull, so let’s think about cyclics. There are two very diverse points of view here. One camp runs a very low cyclic rate so no matter how far you move the stick, you cannot upset the model very much. The other runs a lot of cyclic and just flies the snot out of it.
Personally, I find I like to run fairly low cyclic rates as the model gets small smooth corrections, BUT you have to be VERY in tune with the model since , if you get behind in your control inputs, you have very little cyclic power to bring it back. I found that, initially, I needed a little more cyclic than say Wayne or Cliff as they were staying ahead of the model and anticipating what it was going to need whereas I was strictly reacting to what it did. As I spent hours practicing, I began to notice the model doing the same thing at the same time every time and I could anticipate a little better so I could turn the cyclic rates down and still have full control.

Currently, in hover, I am running about 2 1/2 degrees of cyclic in both pitch and roll with about 30% expo. Something I do differently than some of the other guys, I DO run dual rates. Mine are ON low rate all the time EXCEPT when the wind is blowing hard. I turn it off then and get about a 10% increase in control. Wayne doesn’t need that since he is so good at anticipating what the model is going to do but, even though I am better than I used to be, I can still get behind in the wind.

In idle ups, I run about +/- 5 degrees of cyclic. You can run +/- 6 as the model will do that without binding but I find that as I increase cyclic rates, the model starts to do stupid stuff like yaw when you give a hard roll command. If I keep the rates lower, I have much less of that to deal with.

NOTE: This is what I do and I do NOT recommend this for anyone else. I run 4 idle ups. In Idle 1 I do the two rolls and roll reversal. My roll rate is adjusted for two rolls in about 6 seconds, fairly slow, pitch rate is VERY soft since I don’t want to wiggle the elevator in the middle of the maneuver and rudder is very low also. Rates are so low in this condition, it’s hard to actually fly around as there is not a lot of control here.
Idle 2 is for two loops, I have very low roll and rudder rates and moderate elevator cyclic as that is where I am working the hardest, to make it smooth and round. Idle 3 is where I do all of my flying around and all the rest of my maneuvers except for three. It has a moderately high roll rate, moderate elevator rate and enough rudder rate to do a clean 540 stall turn. I am in this condition about 75-80% of the time. I run Idle 4 to do the push over, cobra roll, and pull-up with inverted pirouette. This condition has a LOT of elevator with a lot of expo, less rudder for a slow 4 second pirouette, and less negative pitch as I want to get near bottom stick so I do not climb like a bandit in the inverted pirouette, which is my normal tendency.

I also run a CRUISE condition, to set up for my autos. Model is trimmed for level flight with moderate cyclic but only 1700 rpm so when I go negative on the auto entry, the motor doesn’t try to overrev so hard. It makes the entry a lot smoother. I think I’m the only one that does that as I’ve never heard of anyone else doing it but it makes the autos easier for me so I use it.

In throttle hold I run moderate cyclics with a moderate rudder. I find, if I have too much rudder available, I tend to suck all the power out of the head with it and can run out of head speed. With a lower rudder rate, I can still do what I need and have a lot more rotor inertia left at the bottom to land the model.

NOTE: Everyone does this a little differently and this is what I do. I do not recommend this as the ultimate setup and post it only for information and discussion. I know Wayne and Cliff both do this considerably differently from me. Obviously their way WORKS, since they have both been on the world team multiple times and the best I could ever do was second alternate, but I now fly better using this than any way I have done before.

Everyone does basic setup a little differently. I was at the contest in Birmingham last weekend and talked quite a bit with Cliff Hiatt and Wayne Mann. While they disagree on some of the finer points at the ends of the spectrum, they basically agree about most things.
What I say is here my own opinion and it may or may not work for anyone else.
I want a model I can fly day in and day out with just routine maintenance. The XL Pro IIK I fly as my primary model is 4 years old right now and has been crashed once. My backup model is less than a year old and has yet to be crashed. Both of these models have a lot of flights on them and need some maintenance. I am in the process of redoing the collective system on my primary model as it has been in continuous use for two years and it needs the pivot tube replaced and new bearings to tighten it back up since the collective arm has developed a little side to side play. It doesn’t seem to have affected the way the model flies but, after I fix it, I may be surprised. It has worn gradually over a long time so I may not notice that performance has dropped off so when I tighten everything up, I may have to readjust my radio a little.

That’s one of the major differences between an F3C model and a 3D model. If you build an FAI model, it is worth the time and effort to get everything as good as you can because, hopefully, the model will never hit the ground. Many 3D models hit the ground pretty regularly and are frequently rebuilt so it would not make sense to spend massive amounts of build time in a model that may get rebuilt totally every 6 months or even sooner. 3D guys can rebuild a crashed model overnight and go fly the next day. If I crash an F3C model, it has to come completely apart and every bolt checked to see if they are bent, all parts checked for damage and trueness, and then reassembled back to as close to perfect as I can get. It may take me three weeks to rebuild after a crash. (Longer if crying time is involved…..........)

When you fly the same model over a long period of time, you get to know that model really well and can feel when something changes or is not right. HEED THOSE WARNINGS! I had my primary model act funny the other day. It had been flying particularly well and all of a sudden the tail just didn’t feel right. I came in to check and as the model transitioned into a hover, it started to pirouette. I was able to get the model down with no damage and found the TR pushrod had fractured right as it came out of the carbon tube so it had started to flex under load while doing aerobatics. It actually broke when I came into a hover to check. Had I ignored the warning, I would have been 300 feet in the air at 80 miles an hour with no TR control. Now I MIGHT have been able to do a pirouetting auto with it but I’m glad I did not have to try.

Q: This is a big can of worms to open, but what characteristics and priorities are most important in a FAI blade?

A: Selecting blades is about like picking a toothbrush, everyone has different priorities.
For me, and I emphasize for me only. I want a blade that I can run at moderate rpm (1450 or so) for fuel economy, that sits well and does not become touchy in the wind. It can move up and down some but they cannot “bite” during collective inputs. In FFF I want a very neutral blade that rolls well and again does not load aggressively. I would prefer a blade that will haul tail too but that’s not the final word. They must auto neutrally also, that is, they must load progressively as I increase pitch. I do not want a blade that grabs all of a sudden if you stick in a little too much pitch too quickly. Now I just described three different sets of blades, so you pick a compromise and hope for the best. I have been fortunate that I have friends that will loan me blades to try so I don’t have to buy 15 sets and then only use one.

Q: I have noticed that many pilots turn down their rpm right before they do the autorotation. I however thought you were supposed to have as much rpm as possible to be able to have enough lift at the end, so I have around 1900rpm when I enter the autorotation

A: In my experience, the high head speed bleeds off quickly anyway due to drag so you really gain very little by using a high head speed on entry.

Q: What effect on stability and performance do blades, paddles, and fly bar have?

A: Depending on what model you have and what you want it to do, all of the above have effects on the feel and performance of the model. F3C models, as a rule, are built to be ultra stable in hover. One of the ways we can do that is to use a very heavy flybar. We usually select a flybar paddle that weighs between 35-55 grams with a fairly thick airfoil and forward CG. There are many types that fit that description but the two I am most familiar with are the FunTech carbons and the MA pro II s which can be built between approximately 28- 52 grams (I personally ran 38 grams). I addition we can use flybar weights to tailor the feel of the cyclics to personal preference.
Blades for an FAI model can be either symmetrical or semi-symmetrical and generally weigh between 185 and 245grams and are very “nose heavy.” The semis tend to be really fast in straight flight, do nice pitch maneuvers, and do autos pretty well but may have some “issues” when rolling. Symmetricals do everything pretty well but may be rpm sensitive in hover and aggressive in aerobatics. Now remember, all of this is subjective and, EVEN WORSE, all of it is interrelated.
Generally I start with a blade that feels comfortable in a hover at the rpm I select. Since the current schedules are K factored 2 for hovering, you must have a blade that will sit for you. I, then, want a blade that generates good straight-line speed and rolls well. Third, I want a blade that I can auto and land even with the blades barely turning. I just described three different sets of blades for one flight so, obviously, it has to be a compromise. To get a good idea of what blade works well, take a look at what the NATs competitors (results in the US and Japan are easy to find) are running and go with one of the top blades. I did an extensive amount of blade testing last year (I borrowed blades from everybody I knew and I have a lot of F3C friends so I had a good selection) and, SURPRISE!!!!!, my choice at the end was the same as nearly everyone else, although we didn’t know it was the same until we all showed up at the NATS with the same blades. Notice, I did not make a blade recommendation here as there are SO many good choices and it really is a personal decision.

Q: What is your philosophy on balancing the heli? (nose heavy, level, doesn’t matter, etc..)

A: I balance a model with 3/4 a tank of fuel so that it hangs from the fly bar very slightly nose down to start with BUT I make sure the swashplate is level (MA tool that sits on main shaft) and pick the model up into a hover. I actually trim the model fore/aft by adding or removing weight until the model hovers with ZERO elevator trim.
I then transition to FFF with 1/2 tank of fuel and there are several things I can do here, If the model noses over, still with the swashplate level, no trim, I can add horizontal fin area, I can move the fin back on the boom (there are limits ), I can lengthen the flybar, or I can thicken the flybar paddles . If it noses up, I can use a smaller fin (or no fin), move it forward on the boom, use a shorter flybar, or use a less draggy paddle. Now realize, all of this interacts so you may end up using a combination of all these.
I am set on the paddles I want to use because of how I want the model to feel in hover, so I vary flybar length and horizontal fin size for FFF trim. If you see my Pro IIK-Ts, you will notice I have a fairly large horizontal fin and a long flybar. In an ideal situation I want the model to track level at 3/4 throttle just cruising along and have the model track absolutely straight when climbing vertically or descending vertically, like in a rolling stall turn. I personally find that I cannot easily make a correction to a model that will not track vertically. If the model wants to fall over on its back, it’s really hard to find and hold a vertical line so I concentrate on adjusting the model until it does.
Now I said I want the swashplate absolutely level fore/aft in all flight conditions and in an ideal situation, I would, but sometimes, I get the model really close and just can’t get it perfect so I throw in 4-5 points of trim. It doesn’t seem to affect FFF very much and will fix a lot of evils BUT, I only do this AFTER I have optimized everything else I can adjust.
Now, in F3C, we always hover first (about 5-6 minutes) then go do our aerobatics so we start with a full fuel load and burn over half of it in hover which is why we trim the model 3/4 full in hover and 1/2 full in aerobatics, because that’s how the model will be in flight. A rear mounted tank really helps here as the model will be very neutral when hovering and get a tiny bit more nose heavy as we progress into aerobatics which seems to make the aerobatics a little more predictable.

Q: I see the majority of FAI competitors wrap the pod/boom in a form-fitting fuselage. I presume this is to provide better resiliency and predictability in windy conditions and also improve the aesthetic end as well?

A: Many of the top F3C flyers are using fuselages on their contest models. Aside from the WOW! factor, the fuses have some distinct advantages but also some disadvantages:
Advantages - A nice sleek fuse is faster in FFF than a stock pod and boom model and as a result gives MUCH better vertical penetration. The darn things go uphill like a rocket and give you more time to make decisions and corrections. They also present very well to judges, that is, they are easy to see and follow. They tend to be quieter in flight as all the mechanical noises are muffled by the enclosure.
Disadvantages - They are a pain in the @ss to work on. You have limited access to the mechanics without taking them apart. Many require that you remove the head to get the top off the fuse. Also, the fuse presents a lot more side area than a pod and boom model in the wind and can be a problem to hover when the wind picks up. If you crash a fuse, the expense to repair the model goes WAY up.

Q: During a FAI competition, what is the maximum wind condition that is considered flyable?

A: I think the FAI wind limit is somewhere around 35 mph which is really a lot. We flew the Team Trails in 2001 (I think, when you get older all of this sort of runs together) in Muncie in a 30mph wind. It was amazing to watch these guys holding the model still in a hurricane, but even then we had some of the best guys landing autos outside the box.

Q: How about Measuring cyclic?

A: This has always seemed obvious to me but several people have asked how to measure cyclic so here’s a pretty easy way to do it. Make sure the blades are spun out to flight position, get a flybar lock, and install so the flybar is always perpendicular to the main shaft. MA makes these for all their rotorheads so we have it really easy. Put your pitch gauge on the master blade (you do have a marked master blade don’t you?) and use the transmitter to set the pitch to zero and turn the rotorhead so the blades are fore/aft parallel to the tail boom. Make sure you’re at zero pitch and push in and hold full right cyclic. Level the pitch gauge to measure the degrees of right cyclic. Push in and hold full left cyclic and again level the pitch gauge. Hopefully, the two numbers you get should be the same or very nearly so. If the two numbers are off more than a quarter degree you may have another set up issue.

To get elevator cyclic rates, turn the head so the flybar is parallel to the tail boom and repeat. I have done this to a lot of models and have been AMAZED at how many have +/- 4 aileron and +/- 5 elevator. I always try to get both roll cyclic and pitch (elevator) cyclic to be the same so the model seems balanced. I set my contest models at +/- 2 1/2 degrees cyclic in hover and +/- 5 degrees in aerobatics as a starting point and then customize them to each flight condition.

A word of warning: Many guys are running as much as +12 degrees collective and +/-8 degrees cyclic so if you apply full pitch AND full cyclic, you can have as much as 20 degrees going to the blades. This can make both the blades and the rotorhead extremely unhappy and they will make nasty noises to let you know. In some situations the blades will actually stall and control gets really difficult as the head doesn’t do what you are telling it to. This is pretty unusual for an F3C model as we rarely run cyclic rates high enough to get into this flight regime but it does happen pretty frequently on some sport model.

Everybody has their own “feel” that they are looking for so cyclic rates are pretty much individual. Like I said, I run +/- 2 1/2 in hover but many sport flyers would be hard pressed to hover my model as they would think the radio quit, but select a rate you are comfortable with, start around +/- 4 degrees, and make both pitch and roll the same and go out and get used to flying with it. It may take a little while but you will find the cyclic rates will start to come down as you get more n tune with the model. Remember, we are talking about an F3C model, a sport model may require more cyclic to do the stuff a sport flyer wants.

Q: Do you use subtrims?

A: I am a BIG proponent of mechanical set up perfection, or as close to it as I can get. One of the things that drives me crazy is the use of subtrims. If the model is mechanically set up correctly, why would there be subtrims in it? Futaba servo arms do not always line up exactly on the axis of the servo and a lot of people use the subtrim to center the arm on the servo BUT if you rotate the servo arm around on the splines, each arm lines up differently so you can FIND one that lines up exactly. It may take a couple of minutes extra, but you are keeping the servo directly in the center of its travel which, theoretically anyway, should give the maximum results.
Now does this ACTUALLY make ANY difference, probably not much if any, but why take chances.

Q: What servo arms are best?

A: Just a thought. Since servo arms have been mentioned, I always use the round servo wheels as they tend to be stiffer and less prone to breakage than the star arms. Over the years, I have broken nearly every kind of servo attachment in flight except the wheels. so I would recommend them for use in all models, F3C and 3D. As a plus, you can rotate the wheels on the servo splines until they line up exactly perpendicular to the axis of the servo or 90 degrees to the pushrod therefore requiring zero subtrim.

Q: What are the biggest issues between F3C vs 3D?

A: We, as F3C competitors, have been asked about going to a 3D format and the new schedules do have a more 3D flavor BUT the move toward this is fairly slow. Schedules are up for rewrite every few years, we have the schedules for 2006 and 2008 already done, and they are very tough, requiring both inside, outside, and inverted work.
I’m going to stick in an opinion here and want to emphasize, this is my opinion and no one else’s so don’t go flaming everyone else for this. There has been a lot of discussion about getting more participation in the AMA classes and F3C. One of the major thoughts was we have all of these terrific 3D flyers in the US that have unbelievable eye hand coordination and great spatial orientation. If we made the F3C schedules into a 3D format, all of these guys would flock to F3C and we would be able to bring the best flyers in the world to contest.

I have spoken to many of the top 3D guys in the USA and if you discount Curtis and Alan, we haven’t seen a lot of these guys. Ask them and they will tell you that they are not even vaguely interested in competing. Now I have watched these guys at fun flies and they will go out one after another and do progressively more aggressive maneuvers to WOW the crowd so they ARE competitive and show it in their flying style BUT if you formalize the contest , the XFC in the US being the exception, no one shows, so there seems to be NO 3D contests, therefore there are no winners but also no losers. I don’t know if that is why 3D is so popular, you cannot be placed in a hierarchy, at least in your own mind. I really have thought about this a lot and might be completely wrong, completely right, or the truth somewhere in the middle. I wish I could figure out how to get these guys involved as they are terrific flyers and could be awesome in F3C.
I will be very interested in hearing everyone’s take on this. Like I said, some of these 3D guys are my good friends and can fly rings around me and would do really well in any competitive situation. I guess it could be the time required to go out and practice and learn the schedules is too much, the hovering maneuvers, though very tough, are not spectacular looking but require huge amounts of practice to be accurate, and everyone KNOWS what you are supposed to be doing so you cannot hide a mistake, but DANG!!!, these guys could be SO GOOD!

Anyway, as far as set up for a more 3D schedule: Since we have outside maneuvers coming in 2006, we are all going to be required to change the setup on our models. Where we now run something like -8/+12 we will need something like -10/+12 for the new schedules. I tried some of the new maneuvers with my sport model (-10/+11) and it worked OK. My current contest model (-8/+12) did not have enough negative pitch to make the model drive into a maneuver when inverted so I tried just overdriving the collective to see if that made a difference and it really did so when I get through with this contest year, I will go back and completely redo my set up to include more negative pitch and make everything symmetrical, probably centered on +1 degree. I think my roll rates will have to increase also as some of the new maneuvers require more. I don’t think anyone will continue to run semi symmetrical blades as they, at least the ones I have tested, have some unusual characteristics when G-loaded while inverted.

Q: What’s the procedure for rolls, do you use a radio mix to keep speed up or use back elevator on entry & at the inverted point.

A: Boy I wish I had a good answer for this. I used to have a real problem rolling my Pro IIs with semi-symmetrical blades, particularly if I rolled to the right. As I rolled inverted on the first roll, the nose of the model would shoot up and kill all my forward speed and then the second roll just sucked. I found that the particular blades I was using required almost zero negative pitch and if I got into the pitch too hard it really screwed up the rolls. 

When I went to a symmetrical blades, a lot of my problems disappeared and I found that rolling left (always roll downwind) the model tracked great but rolling to the right, the model still wanted to slow down ( and waddle). I put in a pmix, ail to ele, about 8% ( it’s different for every model 5-15%) so as I rolled right I get back cyclic. Back cyclic, when the model is inverted, tends to keep the model moving forward and when you program it in, you get the same feed every time and can adjust it to get the model to track like you want. Some models require the same pmix to roll left but require forward cyclic to hold the nose up. Mine never needed that but Dr Ben and I have both run into models that did.

Some guys also have an ail to rudder pmix that gives a stab of rudder as you start the roll to place the nose of the model correctly but this one is a real pain to set up and I would not recommend it for someone that is not VERY familair with a model as you can really screw up everything with this mix unless you know exactly what and why you are doing it.

I use NO elevator at all during a roll, just collective, UNLESS something really screws up and the nose drops and the model heads toward the basement. Then I try to use just enough to keep the model from going into the trees because any more than that and the whole maneuver goes south. Most of the time, if I get a good entry, the model does all the work for me.

Q: Is this pmix on during your whole flight, if so, does this cause any problems with any other aspects of your flight, or do you have this linked to a particular flight mode or switch.

A: I use it in two conditions, the one where I do rolls, and the one where I do Cuban eights, rolling stall turns, and the loop with straight roll. I don’t think it would hurt but I don’t have it turned on anywhere else. Definitely not in hover.

Q: What is the best setup for autos?

A: I run my GY601 in HH all the time. The problem with that is you MUST be able to get the model straight before entering a maneuver or the gyro will hold the model crooked throughout, and all your aerobatics will look like doodoo.
To enter an auto, I use the following:

I slow the headspeed down to 1700 or so from the 1950 I normally turn when doing aerobatics and establish a good line with the model flying parallel to the flight line. I pull pitch with the motor still on and establish a rate of descent and THEN pull the hold switch. The model doesn’t twitch or do anything funny, it just continues as it was.
A lot of guys like to enter the auto from a very high head speed thinking that it will give you more time at the bottom but I find the head speed bleeds off due to drag anyway in the first part of the auto so it’s better for me to start at the rpm I want to use during the auto. I find I have plenty left at the bottom to land the model and rarely bounce the model even on the calmest hot days. A word of warning. Do NOT get ham handed with the tail rotor during an auto as it will suck all the energy reserves out of your rotor system and make it difficult to land smoothly. Use just enough TR to face the model in the direction you want to go.

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