[NSRCA-discussion] the joy of trim

Matthew Frederick mjfrederick at cox.net
Mon Mar 10 02:37:28 AKDT 2008


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
>
> _______________________________________________
> NSRCA-discussion mailing list
> NSRCA-discussion at lists.nsrca.org
> http://lists.nsrca.org/mailman/listinfo/nsrca-discussion 



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