[NSRCA-discussion] the joy of trim

Wayne Galligan wgalligan at att.net
Mon Mar 10 06:13:21 AKDT 2008


If the plane is setup with any positive incidence there will be the tendency 
to pull to the canopy on down lines.  I have experienced this on all my 
planes once they were set up in all other areas.  Doesn't mean there is a 
problem with the airframe.  And it doesn't take very much mix to get the 
down line nice and straight.

Wayne

----- Original Message ----- 
From: "Matthew Frederick" <mjfrederick at cox.net>
To: "NSRCA Mailing List" <nsrca-discussion at lists.nsrca.org>
Sent: Monday, March 10, 2008 4:36 AM
Subject: Re: [NSRCA-discussion] the joy of trim


> That would be cheating. If you have to overcome the problems of an 
> airframe
> by using all those conditional mixes, you need a new airframe.
>
>
> ----- Original Message ----- 
> From: "James Oddino" <joddino at socal.rr.com>
> To: "NSRCA Mailing List" <nsrca-discussion at lists.nsrca.org>
> Sent: Monday, March 10, 2008 12:26 AM
> Subject: Re: [NSRCA-discussion] the joy of trim
>
>
>> 1) Low throttle to down elevator mix.  About 2% only at low end.
>> 2) Rudder to Elevator mix.
>>
>> Jim O
>>
>>
>> On Mar 9, 2008, at 12:07 AM, Keith Black wrote:
>>
>>> OK Bryan, I'll take you up on your offer.
>>>
>>> Plane:
>>>
>>>   Beryll (you've had experience last year with Brett's)
>>>
>>> Problems:
>>>
>>>   1) Pull to canopy on downline
>>>
>>>   2) Tuck to belly on knife edge.
>>>
>>>   (haven't noticed a pull to the canopy on upline, but really didn't
>>> test
>>> that closely)
>>>
>>> History:
>>>
>>> Initial setup incidence was .5+, CG about 175 mm behind leading
>>> edge. First
>>> flights felt very nose heavy, when rolling inverted seemed to need
>>> lots of
>>> down elevator, also the 45 deg up then roll to inverted test dropped
>>> nose
>>> more quickly than I like. Also as noted above it pull to belly on
>>> knife edge
>>> and pulled to canopy on downline.
>>>
>>> To help solve tuck to belly in knife edge I increased the incidence
>>> as much
>>> as I could (without a dremmel) probably a 1.5 to 2 turns. Also moved
>>> CG back
>>> about 3/8" or so to help nose heavy feel. Changes improved nose
>>> heavy feel
>>> and seemed to improve downline pull to canopy a bit, but it needs
>>> further
>>> improvement as it still pulls to canopy in dive. I ended up mixing
>>> out pull
>>> to belly in knife edge as the adjustments didn't help that.
>>>
>>> So what do you suggest? Seems like the move of the CG helped the
>>> inverted
>>> flight and transition to inverted on slow roll. I'm concerned that
>>> increasing the incidence more and moving CG forward may fix belly
>>> tuck in
>>> dive but would lead to nose heavy feel of inverted flight again. I
>>> know can
>>> increase the down elevator (or remove expo) to offset the nose heavy
>>> feel,
>>> but I don't like the transition from upright flight to knife edge to
>>> require
>>> so much top rudder that it throws off the track when at the 1/8
>>> point of the
>>> roll.
>>>
>>> What say you Sensei?
>>>
>>> Thanks,
>>> Keith
>>>
>>> ----- Original Message -----
>>> From: <shinden1 at cox.net>
>>> To: "xvcNSRCA Mailing List" <nsrca-discussion at lists.nsrca.org>
>>> Sent: Saturday, March 08, 2008 10:24 PM
>>> Subject: Re: [NSRCA-discussion] the joy of trim
>>>
>>>
>>>> thanks Lance
>>>> we all know I`m a terrible writer and thats part of my reasoning here
>>>> I have great respect for Matt and his abilities he is a great
>>>> modeler and
>>>> designer.
>>>> I am trying to use past experience when helping with these issues
>>>> as a
>>>> guide to how far out of line these things can get because of a
>>>> misunderstanding that leads into a poor fix
>>>> or a modeler who is not up to the task and trys to take the shortcut
>>>> ,,,there are no shortcuts
>>>> I would be willing to bet 98% of pattern fliers don`t even know
>>>> what their
>>>> down thust is and have never measured it. 1deg down is a lot.
>>>> and most could not find a baseline to start with as a watermark for
>>>> later
>>>> measurements
>>>> I was trying to point out that it should be a method of fine tuning
>>>> rather
>>>> than using it to steer a wayward airplane into submission.
>>>> The wing is the most important ,powerful and effective way to adjust
>>>> flight path ,,, airfoil ,stab placement , engine thrust ,,are way
>>>> down the
>>>> list in importance as seen with a foamy,,
>>>>
>>>> First things first ,,get the wing inc right THEN,, the ac/g ..you
>>>> would be
>>>> surprised at how for off you can fly c/g and get away with it ,,,
>>>> What Matt and I call pulling to the Canopy and what Joe Blow calles
>>>> it i`m
>>>> sure ,, are two different things.{BTW I would bet most of the
>>>> fliers out
>>>> there with differential fix problems ,,are there becuase of an up
>>>> line
>>>> pull,
>>>> usually because your flying a tail heavy airplane } if ou use tail
>>>> weight
>>>> to create a pos angle of attack lots of little problems arise you
>>>> have to
>>>> use inc to creat the lift and C/g to adjust the feel
>>>> earlier I was trying to make the bigger picture nothing against
>>>> what Matt
>>>> was offering ,,,,
>>>>
>>>> I disagree there is more than one way to trim there is only one way
>>>> our accepted outcome is the difference
>>>> I would like to say I`m probably more hard headed than the Next
>>>> guy , so
>>>> I stick to my guns till proven wrong but accept it when I can be
>>>> proven
>>>> wrong,,  ,,  after designing over 15 pattern airplanes and keeping
>>>> notes
>>>> ,,, my outcome notes all say the same thing in the end ,it never
>>>> changes
>>>> ,,even when I get a bright idea to change or tweak the setup it
>>>> leads me
>>>> back to where I started.
>>>> After watching Arch fly his Black magic in the bumpy 25mph winds in
>>>> Crowly
>>>> La. A smoking performance ,,,I might add
>>>> the BM appeared to be on rails then,,watching my own airplane dance
>>>> around
>>>> I realized something I knew But had ignored ,,,it made me go back
>>>> to the
>>>> notes where I found the answer ,,, it never changed!!
>>>> the BM was a great design Properly trimmed BUT,
>>>> I,, had been trying to adjust upline canopy pull with engine thrust
>>>> and
>>>> tail weight ,,,,I don`t have the Luxury of calling the designer and
>>>> asking
>>>> where to put the C/G and wing Inc ,,,I have to find it <G>
>>>> when I realized it needed more wing inc less tail weight and less
>>>> down
>>>> thrust  it reaffirmed my notes and when the next time I flew in those
>>>> conditions it proved me right you have to balance all these things
>>>> The airplane flys around the wing ,,,,let the airplane talk to
>>>> you ,,be
>>>> honest in you evaluations accept nothing but absolute perfection it
>>>> is
>>>> attainable
>>>>
>>>> would anyone like to try an onlist diagnosis of their airplane?
>>>> you tell me the Set up ,,they must be very Accurate give me the
>>>> Symptoms
>>>> ,,and I`ll provide the cure
>>>> you tell us what is happening with the input ,,,BEWARE it can be
>>>> tedious
>>>> and it might include using a saw!!<G>
>>>> any takers ??
>>>> Bryan
>>>> sorry to be so longwinded
>>>> ---- Lance Van Nostrand <patterndude at tx.rr.com> wrote:
>>>>> Bryan,
>>>> I have been anticipating your response but now it seems it won't be
>>>> coming
>>>> soon.  Maybe we can take this offline.  There's no way anyone could
>>>> interpret my response as being argumentative and I know your are
>>>> tough
>>>> enough to take a few pin pricks without flinching.  Certainly I
>>>> have my
>>>> own
>>>> experiences and opinions but those are completely set aside.  I
>>>> believe
>>>> there are always at least 10 correct answers to any modeling
>>>> question but
>>>> each answer is right within its own context.
>>>>
>>>> In other words, I start from 0-0 and have my trim process advance
>>>> from
>>>> there
>>>> and usually get very good results.  I think, if I remember
>>>> correctly your
>>>> old KF article and our live discussions, you start from 1/2 degree
>>>> positive
>>>> inc in wing and stab and advance from there.  Since I know your
>>>> path is
>>>> different from mine I am trying to learn from you.  this is why I
>>>> question
>>>> and ask for deeper explanation.  Maybe it's just not there.  The
>>>> answer
>>>> might be "I never tested in a wind tunnel, can't explain why it
>>>> works, but
>>>> it does so just try it and enjoy."  But I hate to see you bow out
>>>> when
>>>> someone asks for more details.  that makes Krishlan's comment seem
>>>> relevant
>>>> when, knowing how much you help others and contribute to this
>>>> sport, it
>>>> shouldn't be.
>>>>
>>>> --Lance
>>>>
>>>> ----- Original Message -----
>>>> From: <shinden1 at cox.net>
>>>> To: "NSRCA Mailing List" <nsrca-discussion at lists.nsrca.org>
>>>> Sent: Saturday, March 08, 2008 5:32 PM
>>>> Subject: Re: [NSRCA-discussion] the joy of trim
>>>>
>>>>
>>>>> Ok Matt
>>>>> I accept, your probably right ..
>>>>>
>>>>> I will now bow out of the discussion it`s not going anywhere and I`m
>>>>> waiting my time trying to inform, it seems  all the people I`ve
>>>>> helped
>>>>> accomplish what I`m preaching have quit the sport or they are
>>>>> scared to
>>>>> write !!
>>>>> I`ll leave you with this ,
>>>>> demand of perfection is different by each persons ability and goals,
>>>>> sometimes we deceive ourselves in thinking we kow it all or
>>>>> we get caught up in out wording every one and talking nonsense ,,
>>>>> then no
>>>>> one gets anything out of the conversation
>>>>> and then, you die of a thousand pin pricks<G>
>>>>> I can remember sharing pos inc setup with Nat on numerous
>>>>> occasions and
>>>>> Nat out worded me and proved me wrong on paper and you know he
>>>>> can ,, in
>>>>> a
>>>>> Popeye Fried chicken House of all places,
>>>>> However  I find out years Later he now uses My setup I`m proud <G>
>>>>> ok ,I`ll stop beating a dead horse I know better than to start this
>>>>>
>>>>> carry on
>>>>> Bryan
>>>>>
>>>>> ---- rcmaster199 at aol.com wrote:
>>>>>> Bryan,
>>>>>>
>>>>>>
>>>>>>
>>>>>>
>>>>>>
>>>>>> I respectfully disagree on the upline, full power issue. The
>>>>>> downline is
>>>>>> a totally different trim situation because the vectors involved are
>>>>>> different
>>>>>>
>>>>>>
>>>>>>
>>>>>>
>>>>>>
>>>>>> MattK
>>>>>>
>>>>>>
>>>>>>
>>>>>>
>>>>>>
>>>>>>
>>>>>>
>>>>>>
>>>>>>
>>>>>>
>>>>>> -----Original Message-----
>>>>>>
>>>>>> From: Nat Penton
>>>>>>
>>>>>> To: NSRCA Mailing List
>>>>>>
>>>>>> Sent: Fri, 7 Mar 2008 7:16 pm
>>>>>>
>>>>>> Subject: Re: [NSRCA-discussion] the joy of trim
>>>>>>
>>>>>>
>>>>>>
>>>>>>
>>>>>>
>>>>>> I'm thinking, I'm thinking     ----- Original Message -----   From:
>>>>>> shinden1 at cox.net>  To: "NSRCA Mailing List"
>>>>>> nsrca-discussion at lists.f3a.us>  Sent: Friday, March 07, 2008 1:53
>>>>>> PM
>>>>>> Subject: [NSRCA-discussion] the joy of trim      > Matt, I refer
>>>>>> back to
>>>>>> my earlier post  > thrust is not the issue.  > wing inc. will
>>>>>> always
>>>>>> trump thrust,, in power and influence over vertical   > lines.  >
>>>>>> thrust
>>>>>> is a" very fine tune" issue it should not be used to adjust   >
>>>>>> tracking
>>>>>> issues  >  > jump in Nat ,, why do you not need down thrust on your
>>>>>> design??  > Bryan  > ---- rcmaster199 at aol.com wrote:  >> If the
>>>>>> model
>>>>>> pulls to canopy on a�FULL POWER�vertical upline and you   >>
>>>>>> reduce
>>>>>> downthrust, the problem will worsen. You need to add downthrust
>>>>>> >>
>>>>>> (about 1 degree initially, and more if needed). I would not mess
>>>>>> with
>>>>>> CG,
>>>>>>>> at least not yet.  >>  >>  >> �  >>  >>  >> Horizontal flight
>>>>>>>> places
>>>>>> quite a load on the wing....the wing must lift   >> the load
>>>>>> accordingly.
>>>>>> Vertical flight removes the load therefore whatever   >> trim was
>>>>>> found
>>>>>> in horizontal flight will affect the vertical flight. The   >>
>>>>>> simplest
>>>>>> fix is downthrust addition for the condition Mike references,
>>>>>> >> but
>>>>>> assumes that the model is close to begin with.  >>  >>  >> �
>>>>>> >>  >>  >>
>>>>>> Downline flight (NO POWER) is a totally different trim scenario
>>>>>> and may
>>>>>>>> indeed require wing/stab inc adjustment and CG adjustment.  >>
>>>>>>>> >>
>>>>>>>>
>>>>>> �  >>  >>  >> It should be understood�that it is an iterative
>>>>>> process to
>>>>>> get "perfect"   >> trim.  >>  >>  >> �  >>  >>  >> MattK  >>
>>>>>> >>  >>  >>
>>>>>>>>>>>>>>>>>>>> -----Original Message-----  >>  >> From: J N
>>>>>> Hiller  >>  >> To: NSRCA Mailing List  >>  >> Sent: Fri, 7 Mar 2008
>>>>>> 11:33
>>>>>> am  >>  >> Subject: Re: [NSRCA-discussion] YS Questions+more -
>>>>>> Rolls  >>
>>>>>>>>>>>>>>>>>>>>>>>>>>>> The airplane may be flying
>>>>>> with positive trim. Try reducing the down   >> thrust or move the
>>>>>> CG
>>>>>> back.  >>  >>  >> If it doesnt help put it back.  >>  >>  >> Jim
>>>>>> Hiller
>>>>>>>>>>>> �  >>  >>  >> -----Original Message-----  >>  >> From:
>>>>>> nsrca-discussion-bounces at lists.nsrca.org   >>
>>>>>> [mailto:nsrca-discussion-bounces at lists.nsrca.org]On Behalf Of
>>>>>> Michael
>>>>>>>> Wickizer  >>  >> Sent: Friday, March 07, 2008 8:19 AM  >>  >> To:
>>>>>> NSRCA Mailing List  >>  >> Subject: Re: [NSRCA-discussion] YS
>>>>>> Questions+more - Rolls  >>  >>  >> �  >>  >>  >> Bryan:  >>  >>
>>>>>> �  >>
>>>>>>>>
>>>>>> I agree that the plane doesn't know which direction it's flying,
>>>>>> but
>>>>>> then
>>>>>>>> why will a plane fly straight and level then pull to the canopy
>>>>>>>> in
>>>>>>>> uplines?� This has been driving Brett and me crazy for over a
>>>>>>>> year.�
>>>>>>>> Admittedly, it a much shorter drive for me:)  >>  >> �  >>  >>
>>>>>>>> Mike
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> Date: Thu, 6
>>>>>> Mar
>>>>>> 2008 23:13:48 -0500  >>  >> > From: shinden1 at cox.net  >>  >> > To:
>>>>>> nsrca-discussion at lists.nsrca.org  >>  >> > Subject: Re:
>>>>>> [NSRCA-discussion] YS Questions+more - Rolls  >>  >> >  >>  >> >
>>>>>> Chris
>>>>>> ,,
>>>>>> the airplane does not know it`s flying horizontal or vertical
>>>>>> >>  >> >
>>>>>> the wings are still lifting whether up or down that s why we can
>>>>>> use
>>>>>>>>
>>>>>>> the vertical up or down to test this problem ,  >>  >> > Bryan  >>
>>>>>>>>
>>>>>>> ---- krishlan fitzsimmons homeremodeling2003 at yahoo.com> wrote:  >>
>>>>>>>>
>>>>>>>> Lance,  >>  >> > >  >>  >> > > Just a thought though, if going
>>>>>> straight up, up straight down, aren't   >> > > the up and down
>>>>>> ailerons
>>>>>> both inducing equal drag, no lift? I've   >> > > often wondered
>>>>>> if our
>>>>>> straight up test is actually a perfect test for   >> > > this. It
>>>>>> is for
>>>>>> our up and down lines, but what about our 45's or   >> > >
>>>>>> horizontals
>>>>>> where we do indeed have lift on the low aileron and drag   >> > >
>>>>>> on the
>>>>>> other? This would create a different condition I'm guessing..
>>>>>> >> > >
>>>>>> Probably small, but still a little different because as I
>>>>>> mention,   >>
>>>>>>>
>>>>>>> both create drag on the up or downline.. Still, it's the best
>>>>>>> test we
>>>>>>>>>> have I guess..  >>  >> > >  >>  >> > > Chris  >>  >> > >  >>
>>>>>>>>>> >>
>>>>>>>
>>>>>>> Lance Van Nostrand patterndude at tx.rr.com> wrote:  >>  >> > > This
>>>>>> thread is timely because I've been experimenting with   >> > >
>>>>>> differential  >>  >> > > recently on a new design that seems to
>>>>>> need it.
>>>>>> Never needed it   >> > > before on a  >>  >> > > pattern plane
>>>>>> but now I
>>>>>> might. My test is to fly very high, point the   >> > > nose  >>
>>>>>> >> > >
>>>>>> directly at the ground and roll pure aileron. Plane should be
>>>>>> axial,
>>>>>>>>
>>>>>>>> but  >>  >> > > remember that axial is along the vertical CG,
>>>>>>>> which
>>>>>> may not be a line   >> > > that  >>  >> > > pierces the wing LE/
>>>>>> TE. You
>>>>>> need to do it a few times to be sure that   >> > > their  >>  >>
>>>>>> > > is
>>>>>> an axis that everything rotates around and that line is
>>>>>> straight.   >> >
>>>>>>> If it  >>  >> > > wobbles, then we have an issue. Another way to
>>>>>> determine this is to   >> > > do  >>  >> > > unlimited rolls while
>>>>>> flying
>>>>>> straight up. If the airplane   >> > > consistently arcs  >>  >> >
>>>>>> > off
>>>>>> its vertical line, you have a problem.  >>  >> > >  >>  >> > >
>>>>>> Aerodynamics suggests two contributors. One is that the lowered
>>>>>> >> > >
>>>>>> aileron  >>  >> > > increases the lift of the airfoil and lift
>>>>>> creates
>>>>>> drag so this wing   >> > > may  >>  >> > > pull the plane off
>>>>>> axis. the
>>>>>> other is that the spiral slipstream of   >> > > the prop  >>  >>
>>>>>> > > is
>>>>>> pushing down on the right wing and up on the left so up/right
>>>>>> >> > >
>>>>>> aileron is  >>  >> > > more effective than up/left and down/left
>>>>>> is more
>>>>>> effective than   >> > > down/right.  >>  >> > >  >>  >> > > The
>>>>>> overall
>>>>>> effect for most pattern planes is minimal and usually   >> > >
>>>>>> ignorable,
>>>>>>>>>>>> but on IMAC style planes these factors can be significant
>>>>>> and
>>>>>> the   >> > > resulting  >>  >> > > differential corrections may
>>>>>> need to
>>>>>> be adjusted with something as   >> > > simple as  >>  >> > > a prop
>>>>>> change (from 3 blade to 2 for example).  >>  >> > >  >>  >> > > the
>>>>>> correction of course is to start playing with aileron   >> > >
>>>>>> differential.  >>  >> > > Given the contributors I've suggested,
>>>>>> its not
>>>>>> a given which way you   >> > > go with  >>  >> > > the
>>>>>> differential to
>>>>>> correct the problem and the answer might not even   >> > > be
>>>>>> >>  >> >
>>>>>>>
>>>>>> symmetrical.  >>  >> > >  >>  >> > > Note that contributor #1
>>>>>> above will
>>>>>> change if you are flying upright   >> > > or  >>  >> > >
>>>>>> inverted, so it
>>>>>> would seem that a correction for upright flight would   >> > >
>>>>>> simply
>>>>>>>>
>>>>>>>>>> exacerbate inverted flight, but contributor #2 is the same for
>>>>>> any
>>>>>>>>>> flight  >>  >> > > mode but is throttle dependent.  >>  >> > >
>>>>>>>>
>>>>>>>>>> --Lance  >>  >> > >  >>  >> > > ----- Original Message -----
>>>>>>>>
>>>>>>>>>> From: "Koenig, Tom"  >>  >> > > To: "NSRCA Mailing List"  >>
>>>>>>>>>> >>
>>>>>>>
>>>>>>> Sent: Thursday, March 06, 2008 4:45 PM  >>  >> > > Subject: Re:
>>>>>> [NSRCA-discussion] YS Questions+more - Rolls  >>  >> > >  >>  >>
>>>>>> > >  >>
>>>>>>>>>>> My head is spinning!!! The more I think about this, the more
>>>>>>>>>>> questions I  >>  >> > > > have.........rather than answers!
>>>>>>>>
>>>>>>>>>>>>>>>>>> Maybe the contra rotating prop set up on a
>>>>>> Voodoo
>>>>>> X( Nat??) maybe   >> > > > the  >>  >> > > > answer??  >>  >> > >
>>>>>> >  >>
>>>>>>>>>>> I still 'feel', that the best rolls I get are with a 0
>>>>>> differential   >> > > > set  >>  >> > > > up-BUT- somehow I
>>>>>> 'drive' that
>>>>>> wing to 0 ( or should that be some   >> > > > sort  >>  >> > > > of
>>>>>> equilibrium??) during the rolls. Certainly in my case, it seems
>>>>>> >> > >
>>>>>>> to be  >>  >> > > > Pilot dependant!!!  >>  >> > > > I'm
>>>>>>> starting to
>>>>>> think that my rudder control has turned to the  >>  >> > > >
>>>>>> proverbial
>>>>>> trying to micro analyse what's happening!  >>  >> > > >  >>  >> >
>>>>>> > >
>>>>>> Tom
>>>>>>>>>>>>>>>>>>>> -----Original Message-----  >>  >> > > >
>>>>>> From:
>>>>>> nsrca-discussion-bounces at lists.nsrca.org  >>  >> > > >
>>>>>> [mailto:nsrca-discussion-bounces at lists.nsrca.org] On Behalf Of
>>>>>> >>  >> >
>>>>>>>> shinden1 at cox.net  >>  >> > > > Sent: Friday, 7 March 2008 9:15 AM
>>>>>>>>
>>>>>>>>>>> To: NSRCA Mailing List  >>  >> > > > Subject: Re:
>>>>>> [NSRCA-discussion] YS Questions+more - Rolls  >>  >> > > >  >>
>>>>>> >> > > >
>>>>>> what happens on a 4piont?  >>  >> > > > Bryan  >>  >> > > > ----
>>>>>> Del
>>>>>> Rykert wrote:  >>  >> > > >> The general consensus has been that
>>>>>> the
>>>>>> faster moving molecules   >> > > >> over  >>  >> > > > the top
>>>>>> surface
>>>>>> don't require as big as a deflection as the aileron   >> > > >
>>>>>> that  >>
>>>>>>>>>>> deflects towards the bottom of the plane. What one tries to
>>>>>> achieve   >> > > > is  >>  >> > > > the plane tracks as purely
>>>>>> straight
>>>>>> on a string as possible while   >> > > > one  >>  >> > > > rolls
>>>>>> both
>>>>>> directions without introducing any yaw.  >>  >> > > >>  >>  >> >
>>>>>> > >>
>>>>>> Del
>>>>>>>>>>>>>>>>>>>>>> ----- Original Message -----  >>  >> > >
>>>>>>>>
>>>>>> From:  >>  >> > > >> To: "NSRCA Mailing List"  >>  >> > > >> Sent:
>>>>>> Thursday, March 06, 2008 2:49 PM  >>  >> > > >> Subject: Re:
>>>>>> [NSRCA-discussion] YS Questions+more - Rolls  >>  >> > > >>  >>
>>>>>> >> > >
>>>>>>>>>>>>>>>>> Nat and all you other aerodynamicists,  >>  >> > >
>>>>>>>>
>>>>>>>>>>>>>>>> I thought that the rational for "aileron
>>>>>> differential"
>>>>>> was that  >>  >> > > > upward deflection causes more drag than
>>>>>> downward
>>>>>> deflection so to  >>  >> > > > equalize drag and prevent yaw with
>>>>>> aileron
>>>>>> deflection, aileron  >>  >> > > > differential is needed. It
>>>>>> seems that
>>>>>> you guys are now saying that  >>  >> > > > ain't so. Please
>>>>>> elaborate.
>>>>>>>>>>>>>>>>>>>>>>>> George  >>  >> > > >> >  >>  >> > > >>
>>>>>>> ---- Nat Penton wrote:  >>  >> > > >> >  >>  >> > > >> >
>>>>>> =============
>>>>>>>>>>>>>>> IMO center hinged or top hinged is OK. With top hinge,
>>>>>> to
>>>>>>>>>>>>> achieve  >>  >> > > > equal vertical travel of the trailing
>>>>>> edge requires different   >> > > > angular  >>  >> > > > travel,
>>>>>> up vs
>>>>>> down. The objective is zero aerodynamic differential.  >>  >> > >
>>>>>> >> >
>>>>>>>>>>>>>>> Ron I don't think a fairing would prevent separation
>>>>>> but,
>>>>>> how   >> > > >> > are  >>  >> > > > you able to fair the gap
>>>>>> using the
>>>>>> top hinge ? Nat  >>  >> > > >> > ----- Original Message -----
>>>>>> >>  >> >
>>>>>>>
>>>>>>>>> From: ronlock at comcast.net  >>  >> > > >> > To: NSRCA Mailing
>>>>>>>>> List
>>>>>>>>>>>>>>> Sent: Thursday, March 06, 2008 7:20 AM  >>  >> > > >> >
>>>>>> Subject: Re: [NSRCA-discussion] YS Questions+more - Rolls  >>  >>
>>>>>> > > >>
>>>>>>>>>>>>>>>>>>>>>>>>> And while your at it, I'd
>>>>>> appreciate
>>>>>> some discussion of the   >> > > >> > impact  >>  >> > > > of the
>>>>>> top
>>>>>> hinge system as seen on Viavat, and Prestige birds -   >> > > >
>>>>>> (top  >>
>>>>>>>>>>> hinged, with fairing that eliminates the gap at deflection)
>>>>>>>>
>>>>>>>>>>>>>>>>>>>>>> Thanks, Ron Lockhart  >>  >> > > >> >  >>
>>>>>>>>>>>>> -------------- Original message --------------   >>  >> > >
>>>>>>>>> From: vicenterc at comcast.net  >>  >> > > >> >  >>  >> > > >> >
>>>>>>>>> Nat,
>>>>>>>>>>>>>>>>>>>>>>>> Could you explain why the differential
>>>>>> should be different for  >>  >> > > > non-center hinged? I
>>>>>> understand
>>>>>> that the mechanical configuration   >> > > > of  >>  >> > > > non-
>>>>>> center
>>>>>> hinged requires differential to obtain same travel in   >> > > >
>>>>>> both
>>>>>>>>
>>>>>>>>>>> directions. However, the travel up and down should be close to
>>>>>>>>>>> equal.  >>  >> > > >> >  >>  >> > > >> > Thanks,  >>  >> > >
>>>>>>>>
>>>>>>>>>>>>>>>> --  >>  >> > > >> > Vicente "Vince" Bortone  >>  >>
>>>>>>>
>>>>>>>>>>>>>>>>>>> -------------- Original message --------------
>>>>>>>>>>>>>>> From: "Nat Penton"  >>  >> > > >> >  >>  >> > > >> >
>>>>>> Tom
>>>>>>>>>>>>>>> It's just something that is peculiar to the Southern
>>>>>>>>
>>>>>>>>>>> Hemisphere.  >>  >> > > >> >  >>  >> > > >> > Changing wing
>>>>>> incidence will not help. Unless things are really  >>  >> > > >
>>>>>> screwed
>>>>>> up , at our roll rates, centrifugal forces are too low to  >>  >>
>>>>>> > > >
>>>>>> cause a problem. You want zero differential, aero speaking
>>>>>> ( same  >>
>>>>>>>>
>>>>>>>>> up/down if center hinged ).  >>  >> > > >> >  >>  >> > > >> > I
>>>>>> find the best check is the fast half-roll in the vertical up.
>>>>>> >>  >> >
>>>>>>>
>>>>>>> Regards Nat  >>  >> > > >> > ----- Original Message -----   >>
>>>>>>> >> >
>>>>>>>
>>>>>>>>> From: Koenig, Tom  >>  >> > > >> > To: NSRCA Mailing List  >>
>>>>>>>>> >>
>>>>>>>
>>>>>>>>>> Sent: Wednesday, March 05, 2008 7:24 PM  >>  >> > > >> >
>>>>>> Subject:
>>>>>> Re: [NSRCA-discussion] YS Questions+more  >>  >> > > >> >  >>  >>
>>>>>> > > >>
>>>>>>>>>>>>>>>> Hi Troy!  >>  >> > > >> >  >>  >> > > >> > Thanks
>>>>>> for
>>>>>> the info. I thought you would be toiling away on  >>  >> > > >
>>>>>> the next
>>>>>> developmental stage of these engines!!  >>  >> > > >> >  >>  >> >
>>>>>> > >> >
>>>>>> Hopefully soon, I can find the time to get flying again. I am
>>>>>> >>  >> >
>>>>>>>
>>>>>>> looking forward to running this little beast. I am still a
>>>>>>> little  >>
>>>>>>>>>>> concerned in keeping it quiet though.  >>  >> > > >> >  >>  >>
>>>>>>>
>>>>>>>>>> Four blade props? I have some of the 18.1 x 12 two bladers  >>
>>>>>>>>
>>>>>>>>> but I just cant see how I'll shut the thing up with these paint
>>>>>>>>
>>>>>>>>>>> stirrers??  >>  >> > > >> >  >>  >> > > >> > Also-one more
>>>>>> question to any of you out there in pattern  >>  >> > > > land.
>>>>>> >>  >>
>>>>>>>
>>>>>>>>>>>>>>>>>>> I have struggled with aileron differential for
>>>>>> years. I am  >>  >> > > > just not happy with the rolls. I have
>>>>>> tried
>>>>>> various design   >> > > > fixes-but  >>  >> > > > about the only
>>>>>> one
>>>>>> that
>>>>>> seems to work is to get the wing back to   >> > > > 0-0 (  >>  >>
>>>>>> > > >
>>>>>> which can be achieved by a few ways, design, mix or thumbs)   >>
>>>>>> > > >
>>>>>> Differential  >>  >> > > > itself does not seem to work if the
>>>>>> wing is
>>>>>> POA ( well...it works   >> > > > for  >>  >> > > > half the
>>>>>> roll !)  >>
>>>>>>>>>>>>> Another black magic fix appears to be to run parallel  >>
>>>>>>>>
>>>>>>>>> ailerons-but this only 'sorta' seems to fix it. I like the feel
>>>>>> of
>>>>>>>>>>>>> equal% chord ailerons however.  >>  >> > > >> >  >>  >> >
>>>>>>>
>>>>>>>>> I am frustrated with it-I like my planes to roll as if they  >>
>>>>>>>>
>>>>>>>>> had a string up its ...........well you know!  >>  >> > > >> >
>>>>>>>>
>>>>>>>>>>>>> OK-any 'secrets' I need to know??? Very good elevator work
>>>>>>>>>>>>>>> fixes it ( hence my 0-0 comment)  >>  >> > > >> >  >>
>>>>>>>>
>>>>>>>>>>> Tom  >>  >> > > >> >  >>  >> > > >> >  >>  >> > > >>
>>>>>>> --------------------------------------------------------------------
>>>>>>>>>>>>>>> ----  >>  >> > > >> >  >>  >> > > >> >  >>  >> > > >> >
>>>>>> _______________________________________________  >>  >> > > >> >
>>>>>> NSRCA-discussion mailing list  >>  >> > > >> >
>>>>>> NSRCA-discussion at lists.nsrca.org  >>  >> > > >> >
>>>>>> http://lists.nsrca.org/mailman/listinfo/nsrca-discussion  >>  >>
>>>>>> > > >>
>>>>>>>
>>>>>>>>>>>>>>>>>>>>>>>
>>>>>>> --------------------------------------------------------------------
>>>>>>>>>>>>>>> ----------  >>  >> > > >> >  >>  >> > > >> >  >>  >> >
>>>>>>>
>>>>>>>>> _______________________________________________  >>  >> > > >> >
>>>>>> NSRCA-discussion mailing list  >>  >> > > >> >
>>>>>> NSRCA-discussion at lists.nsrca.org  >>  >> > > >> >
>>>>>> http://lists.nsrca.org/mailman/listinfo/nsrca-discussion  >>  >>
>>>>>> > > >>
>>>>>>>
>>>>>> _______________________________________________  >>  >> > > >> >
>>>>>> NSRCA-discussion mailing list  >>  >> > > >> >
>>>>>> NSRCA-discussion at lists.nsrca.org  >>  >> > > >> >
>>>>>> http://lists.nsrca.org/mailman/listinfo/nsrca-discussion  >>  >>
>>>>>> > > >>
>>>>>>>
>>>>>>>>>>>>>>>>>>>>
>>>>>> _______________________________________________  >>  >> > > >
>>>>>> NSRCA-discussion mailing list  >>  >> > > >
>>>>>> NSRCA-discussion at lists.nsrca.org  >>  >> > > >
>>>>>> http://lists.nsrca.org/mailman/listinfo/nsrca-discussion  >>  >>
>>>>>> > > >
>>>>>> _______________________________________________  >>  >> > > >
>>>>>> NSRCA-discussion mailing list  >>  >> > > >
>>>>>> NSRCA-discussion at lists.nsrca.org  >>  >> > > >
>>>>>> http://lists.nsrca.org/mailman/listinfo/nsrca-discussion  >>  >>
>>>>>> > >  >>
>>>>>>>>>> _______________________________________________  >>  >> > >
>>>>>> NSRCA-discussion mailing list  >>  >> > >
>>>>>> NSRCA-discussion at lists.nsrca.org  >>  >> > >
>>>>>> http://lists.nsrca.org/mailman/listinfo/nsrca-discussion  >>  >>
>>>>>> > >  >>
>>>>>>>>>>>>>>>>>>>>>> Chris  >>  >> > >  >>  >> > >  >>  >> >
>>>>>>>
>>>>>>>>>>>>>>>>>>>>>>>> ---------------------------------
>>>>>>>>
>>>>>>>>>> Never miss a thing. Make Yahoo your homepage.  >>  >> >
>>>>>> _______________________________________________  >>  >> >
>>>>>> NSRCA-discussion mailing list  >>  >> >
>>>>>> NSRCA-discussion at lists.nsrca.org
>>>>>>>>>>> http://lists.nsrca.org/mailman/listinfo/nsrca-discussion  >>
>>>>>>>>
>>>>>>>>>>>> _______________________________________________
>>>>>> NSRCA-discussion mailing   >> list  NSRCA-
>>>>>> discussion at lists.nsrca.org
>>>>>>>>
>>>>>> http://lists.nsrca.org/mailman/listinfo/nsrca-discussion  >>  >
>>>>>> _______________________________________________  > NSRCA-discussion
>>>>>> mailing list  > NSRCA-discussion at lists.nsrca.org  >
>>>>>> http://lists.nsrca.org/mailman/listinfo/nsrca-discussion  >
>>>>>> _______________________________________________  NSRCA-discussion
>>>>>> mailing
>>>>>> list  NSRCA-discussion at lists.nsrca.org
>>>>>> http://lists.nsrca.org/mailman/listinfo/nsrca-discussion
>>>>>>
>>>>> _______________________________________________
>>>>> NSRCA-discussion mailing list
>>>>> NSRCA-discussion at lists.nsrca.org
>>>>> http://lists.nsrca.org/mailman/listinfo/nsrca-discussion
>>>>
>>>> _______________________________________________
>>>> NSRCA-discussion mailing list
>>>> NSRCA-discussion at lists.nsrca.org
>>>> http://lists.nsrca.org/mailman/listinfo/nsrca-discussion
>>>> _______________________________________________
>>>> NSRCA-discussion mailing list
>>>> NSRCA-discussion at lists.nsrca.org
>>>> http://lists.nsrca.org/mailman/listinfo/nsrca-discussion
>>>
>>> _______________________________________________
>>> NSRCA-discussion mailing list
>>> NSRCA-discussion at lists.nsrca.org
>>> http://lists.nsrca.org/mailman/listinfo/nsrca-discussion
>>
>> _______________________________________________
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>> NSRCA-discussion at lists.nsrca.org
>> http://lists.nsrca.org/mailman/listinfo/nsrca-discussion
>
> _______________________________________________
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> http://lists.nsrca.org/mailman/listinfo/nsrca-discussion 



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