[NSRCA-discussion] the joy of trim

Lance Van Nostrand patterndude at tx.rr.com
Mon Mar 10 19:29:41 AKDT 2008


Keith,

As a good AeroSlave customer who's only problem is keeping his airplane out 
of the path of others, you knew that paying 4X for a plane doesn't guarantee 
it comes with instructions in English that tell you what you need to know.

LOL,
--Lance

> ----- Original Message ----- 
> From: "Keith Black" <tkeithblack at gmail.com>
> To: "NSRCA Mailing List" <nsrca-discussion at lists.f3a.us>
> Sent: Monday, March 10, 2008 12:24 PM
> Subject: Re: [NSRCA-discussion] the joy of trim
>
>
>> Nat, I asked around to try and determine this and was told that the
>> horizontal canopy seam (flat part when canopy is removed) should be used
>> to
>> determine the thrust line. Other than that it wasn't specified. The ship
>> came with no directions other than some hardware recommendations from 
>> Troy
>> Newman.
>>
>> Keith
>>
>>
>> ----- Original Message ----- 
>> From: "Nat Penton" <natpenton at centurytel.net>
>> To: "NSRCA Mailing List" <nsrca-discussion at lists.f3a.us>
>> Sent: Sunday, March 09, 2008 7:17 PM
>> Subject: Re: [NSRCA-discussion] the joy of trim
>>
>>
>>> Keith
>>> Where is the thrustline ??     Nat
>>>
>>> ----- Original Message ----- 
>>> From: "Keith Black" <tkeithblack at gmail.com>
>>> To: "NSRCA Mailing List" <nsrca-discussion at lists.f3a.us>
>>> Sent: Sunday, March 09, 2008 3:07 AM
>>> Subject: Re: [NSRCA-discussion] the joy of trim
>>>
>>>
>>>> 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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>> http://lists.nsrca.org/mailman/listinfo/nsrca-discussion
>>
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