lg8

Brian C,
Hi Brian, I hope you are well.
Firstly to say many thanks for your excellent hospitality atlast years Triple Crown.
I continue to enjoy F3A in my retirement; I just wish I hadstarted a long time ago.
I seem to have to practise a lot to make small gains and generally have poor concentration at the Scottish competitions making stupid mistakes.

Ok to the Episode trimming problems I have.
I forgot one important piece of information about this observation.
At the time we were doing the prop test on 2 Episodes, another club member (Paul C) has just got one.
The left wing dropping screwing out happens on both planes and both are cured by fitting the Mejlik.
If youlook at the pitch shape on the Falcon they have a lot of twist close to the hubwere as the Mejlik is similar from centre to the tip.

I am certainly not expert enough to rule out any incorrect set up with my model.

To answer your questions:
We initially did change the right thrust twice; it was increased due to pulling to the left on verticals. Two washers worth of extra right thrust had it going up straight.
Incidentally the motor is a Pletenburg advanced on mine and a Q80 on Paul’s.

The wing incidence is at factory settings on both planes with no adjusters as yet.
I checked using a gimballed laser and the wings appear to bee qual. I have not measured the incidence.

We did find that the elevators half throws were out on minebut corrected this with a digital throw gauge, both now equal. I use 1 deg more down that up

The ailerons are set the same when trimmed for level flight they look both the same. I can’t see any trim difference in either half.

The canopy/canaliser I have used 2 x 3mm thumb screws aswell as the catches.
I saw the video someone posted of it all moving around.

The effect is with inside and outside, maybe less outside but I can’t guarantee that my fingers/thumbs are the same.

I have no rudder trim it looks zero and appears to be straight down with no power.

Have pulled hard at the bottom of a straight down and no wing drops.

Another observation is that I have a very small amount ofadverse roll on knife edge.
How can I get rid of this?

I am not ruling out any of the above as not being correct but simply swapping props fixes the left screw out.
I wish someone else could do this prop swapto confirm it.

Bryan H, thank you for taking the time to reply.
Are you saying that I could improve my trim set up so that the prop change would have much less effect?
I have not measured the factory set incidence yet.

Thanks & regards
Colin

lg8

Malcolm,
Thanks for the reply.
I would appreciate you having a look at this on Saturday for me.
I've been reading your post about the Hybird and I hope you can get it sorted after putting so much into it, time & $'s.
Fingers crossed that the weather is OK for the weekend.

Regards
Colin

serious power

Hi Colin,
Changing props can affect trim but it is normally quite subtle. Though different props can have different effects at different flight speeds.
However it's most likely that it is showing up an underling issue.
Re check your wings and tails - do so at several positions along each panel.
Re-do the flight observations - carefully and preferably in nice still air - if you can find any of that around Scotland .
You may have multiple issues , for eg incidence someplace and some lateral imbalance - that would seem to be the case.
If moving the wing incidence requires surgery then perhaps remove some downthrust for a flight or two to see. Not quite the same as reducing incidence but is changing the prop to incidence relationship similarly.

Bryan H may be better placed to comment further on all of this and the roll couple - from a distance so to speak
If the couple is very small you can mix it out for now anyway.

Getting out with someone experienced like Malcolm is a good idea.

Brian

flyncajun

Colin

I don`t want to be Vague so this advise is in the matter of importance/ In the order of what adjustments are most important

#1 it`s important to do all the checks you can on throw geometry and making sure nothing is loose or that there is no slop in the controls first.
#2 It`s always assumed the design is set up perfect ( none are from any factory ) it`s not possible or reasonable to expect. We as modelers need to be better in this area. the factory is only responsible for getting the settings in the ball park. We are responsible for the rest of the measurements.
#3 Measure every thing as accurately as you can to make sense of the problem, if nothing makes sense. something is over or under adjusted. there is no Areo magic going on. on any plane if the design is sound, and this one is.
#4 Cg and wing inc. is responsible for 90% of all these problems. Where you may want to fly the c/g and where the model is capable of flying the c/g for the wing setting is not always the same on factory adjustments. the Wing inc. setting dictates where the CG can be set.
#5 don`t be afraid to make inc changes, I`m 100% certain this is where your problem is.

Over adjusted wing inc. will cause roll coupling( Always adverse ), especially on hard rudder ,and tip stalls, this is what you are having. and it`s showing up as a yaw problem, or squirting off in radius on certain pulls. I have adjusted a few of these airplanes and reduced the wing inc by over .6 deg to correct this issue. And the c/g needs to be more forward on this design than guys want to run.

I would get the best pilot you know Maybe Malcolm to test fly the plane and make sure you have an issue and not a problem elsewhere, like input from you or the like. I don`t know your skill level but it`s always good to have someone else fly and confirm the problem before you start adjusting.

I have Brett

Bryan

lg8

Bryan / Brian
Thanks for the assistance. Malcolm has offered to fly it and check it out at this weekends comp - weather permitting.
After an email suggestion from Malcolm I have re-measured my Stab fences and found the Port one to have about 3mm tow out.
Should these Stab fences be Vertical with the Fin or 90 deg to the anhedral stab top & bottom?

Colin

blake26m

Hi Colin,

Good piont about the Stab fences. I have mine mounted at 90 deg to the stab itself but i will be interested to hear other opinions.
I was adjusting my C.G lastnight. I have moved my flight packs back about 20-25mm and it has made all the difference in vertical rolling aswell as inverted flight.
Very happy with the model so far. I am using a PT Carbon 21x14 propeller and experience no roll out issues.

Mike

flyncajun

As previously stated by Tony F. who has a lot more time on this plane than most.
All add on fences should be parallel to the centerline of the fuse anything else will give you rudder trim and yaw issues at different attitudes, spin entry`s, landing ,stall turns ECT ( as the model slows) and should only be as big as needed. or they will start working against you.

This goes for all models. drag on flying surfaces should only be a byproduct of lift, if not, it`s working against you some where. And that's always in a area out of your control.
If you need the drag to make the plane track correctly , your airplane is miss adjusted, or miss aligned. even on the rudder

Bryan

pippy

Hi all, Colin's question was even though the fence is parallel to the centreline are they set at 90° to the Stab as it is an anhedral type or are they also parallel (vertical) to the rudder.

underdw

My Feedback: (2)

I've a couple hundred flights on my Episode now and can happily say that I've "bonded" with it.
In response to Tony's instruction to add bigger stab fences, I added a 3rd set. Results in more than a few snickers at the field, but seems to do the trick.

I continued to struggle with my spin breaks. If I wasn't exactly wings-level during entry, a tip would suddenly drop quickly before the nose dropped. Tried many combinations of elev throw, aileron reflex, idle speed, and CG with moderate improvement.
Pippy's post on his low-speed stability improvement with wing fences prompted me to try my own today.

Temporary attachment, made of 6mm depron.

I too had a drastic improvement, especially in inverted spins. Now always a straight-forward nose break, with ail/rudd required to get the wings rotating!
A bad side-effect seems to be a change to the knife-edge behavior. I previously had very little (2%) Rud-elev mix. The plane now pulled to the canopy hard, and requires 20%! Will need to go to a multi-pt mix to deal with higher rudder deflections for F maneuvers. Not much change in Rud-Ail mix.
Overall, I will have to decide if they are worth it, or if there is an alternate shape wing fence that doesn't change the KE flight so much.

I can't come up with an aerodynamic reason for this behavior, Thoughts anyone?

Dan

f3a05

That's the shape that I'm using (3mm depron)
I already had a smallish amount of rudder to down elevator mixing; the wing fences didn't alter it.
Like the previous poster, they made a big improvement to spin entries---no more unpredictable tip-stalling (also helpful in landings).
Perhaps the shape in the previous post might be improved by removing the part ahead of the L/E?---See the shape of the wing fences on the Citrin Bipe, which seems to be successful.

patternflyer1

My Feedback: (11)

3mm depon is not strong enough imo. I tried wing fences, ok, well Chip put them on my Nuance last year before the nats. 6mm was used. Much stronger. I didnt notice what you are saying at all. Just that the tail didnt dip quite so much in rolls. Less rudder throw needed, and I think i changed rudder expo.

Something Tony told me which works for me is to keep the throttle on and keep the nose high and it works for my spin breaks. Maybe he will chime in.

Chris

f3a05

3mm depron is strong enough for flight loads--but, obviously, is susceptible to hangar rash/transport damage.
I think it's tricky to compare the Episode to the Nuance--unless the Nuance has the DTFS wing.
And then the canalyser has a big influence on Rudder power and sensitivity.

pippy

Hi dan, although mine work very well as I have said before, I believe I have them in the wrong location based on feedback from fellow fliers and as seen on lots of planes at the European Championships. I placed mine 1/3 wing span I. From the wing tip but evidence says they should be approx 1/3 from the root. Also the don't need to be tall at all but usually the do cover most of the chord. I may try this at some stage but I will wait until most of the flying season is done.

blake26m

Would the Sebart Mytho's style wings fences combine the best of both worlds so?

pippy

You are spot on mikey. That's what I was talking about in the contra thread.

underdw

My Feedback: (2)

Thanks for the good suggestions/thoughts guys. I will try them in the next few weeks and report back.
Many of the US folks who might chime in are heading to our Nationals.
Regards, Dan

blake26m

Practice!

patternflyer1

My Feedback: (11)

I've flown lots of 3mm depron foamies. Even at slow speeds 3mm bends and pretty much goes where it wants unless fully supported causing trimming issues. That's why we use so many carbon rods on them. I can't imagine using 3mm on a 2m pattern plane at cruising speed. If you have access to a gopro, I would love to see a video of what they really do during flight. Maybe I am wrong.

Chris

oh, and my Nuance had dtfs wings and Episode stabs. Was an a Episode minus the Can.

RuneG

I had an idea when we had the FigM with the Integrated half roll to add a sharkfin on a Xigris I had and tried to use 6mm depron as I had this and it was easy to cut , In the first M I saw a smal white piece falling off the plane ..

f3a05

[QUOTE=RuneG;11847782]I had an idea when we had the FigM with the Integrated half roll to add a sharkfin on a Xigris I had and tried to use 6mm depron as I had this and it was easy to cut , In the first M I saw a smal white piece falling off the plane ..[/QUOTE
All I can say is that my little fences near the wing tips have stayed on over about 50 flights now, spin entries are easier, and I haven't seen any bad side effects.
Incidentally,before I'd had the Episode long enough to be more cautious/careful, I too had a bigger piece come off in the "shark fin area", i.e. the canopy and canalyser....

RuneG

it get off in the first M , it was just the base left rest was blown off... well I made a new one i balsa

blake26m

Just a picture from lastnight. I think i will try the Seba style fences with some 6mm depron.

patternflyer1

My Feedback: (11)

I use Welders Adhesive to install my 6mm depron stab fences on the Episode. I think Chip used CA on my wing fences. They were difficult to take off. I haven't had any issue so far yet. Probably should check them though Rune.. I really think the depron for me was temporary for testing, but somehow, they are still there. Lol

Chris

RuneG

I also was thinking temporary made the fin With a base glued the fin to the base and used tape on the base to the canopy, but the fin broke off just over the glue..but its no problem any more the Xigris is sold and I fly Spark and so fare happy With that!

omsflyer

What is the deciding factor for the size of fins? Thanks Charlie