<div>I'm fine with that also.</div> <div> </div> <div>Thanks, </div> <div> </div> <div>C<BR><BR><B><I>Matthew Frederick <mjfrederick@cox.net></I></B> wrote:</div> <BLOCKQUOTE class=replbq style="PADDING-LEFT: 5px; MARGIN-LEFT: 5px; BORDER-LEFT: #1010ff 2px solid">Chris and Bryan,<BR><BR>I'd be happy to help edit this for a K-Factor issue. Since I fly with Bryan <BR>I have a good insight to his thought process, and it would be easy for me to <BR>clean this up.<BR><BR>Matt<BR>----- Original Message ----- <BR>From: <SHINDEN1@COX.NET><BR>To: "NSRCA Mailing List" <NSRCA-DISCUSSION@LISTS.NSRCA.ORG><BR>Sent: Tuesday, March 11, 2008 10:05 PM<BR>Subject: [NSRCA-discussion] triangulation trimming<BR><BR><BR>> triangulation trimming,<BR>> this is going to be long winded,<BR>> I want to preface this discussion by saying I have learned a great deal <BR>> from Dean Pappas one of my hero`s in the sport,,Jim Oddino I read these <BR>> guys all the time
,,Nat Penton ,,I learned a great deal about painting <BR>> from Mike Harrison who is always willing to tell you what he knows <G>and<BR>> I have looked up to Earl Haury as an all around Teacher and appreciate <BR>> those guys for their hard work in the sport ahead of me and willingness <BR>> to share what they know.<BR>> Now let me say I am no flight engineer or aerodynamic Guru , I`ll leave <BR>> that title to Nat Penton as he deserves it, But the two guys that started <BR>> this flying madness were,, by cycle mechanics,as we all know .<BR>> so I`m in good company<BR>> After trimming over 15 of my own designs and trimming and building two <BR>> or three airplanes a year for about 20 years I have a lot of practical <BR>> knowledge on this subject matter and have kept notes. to verify my <BR>> observations I hope this will help.<BR>> A better Flyer with more experience will be a better trimmer because he <BR>> demands more from his
airplane ,,but being a better trimmer will earn you <BR>> better flying skills .<BR>> so here we go<BR>> Mike ,Keith, Jim and Don, thank you for your patience<BR>><BR>> For the purpose of this discussion tail heavy nose heavy is relative to <BR>> the recommended C/G and not always an extreme position just a way to <BR>> example it.<BR>><BR>> If you are using a 0-0 setup things may- be alittle different as to what I <BR>> say and what you see on your airplanes as you fly them<BR>> my set up and your set up are not to be equated with each other.<BR>> and I think that's where some of the confusion comes in you having only <BR>> experienced your set ups.<BR>> However ,,left rudder tuck is a symptom of the airplane being tail heavy <BR>> on all pattern models no matter the set up, as long as the stab and <BR>> elevators are accurately adjusted , Extreme tail heavy will mean both <BR>> knifes will tuck to the belly. it is just a
symptom that tells me the cure <BR>> and allows me to diagnose trim problems <SEE Chad to reply my><BR>> Jim O,<BR>> Any wing has to produce lift, to fly and there are two ways to do it, add <BR>> pos inc to the wing according to the datum line on the fuse My Method <BR>> or,, add pos inc to the fuse, the 0-0 method ,,,by this I mean , flying <BR>> the airplane a little tail heavy to achieve pos inc ,, there is no way <BR>> around it ,the wing has to have a pos angle of attack to produce lift and <BR>> fly level and lift 11 pounds of balsa and Glass.<BR>> vertical c/g has no factor on this discussion I don`t understand enough <BR>> about it to discuss it,{G}<BR>> The stab does not induce the lift ,,it controls the lift of the wing and <BR>> steers the wing and fuse. {no arguments here please I`m trying to make <BR>> the bigger picture I know it does contribute lift and share the lift <BR>> load,}<BR>><BR>> A ,0-0 or sub
1/2pos set up will cause some or all of these problems <BR>> ,,for you guys set up 0-0 ,, check um off ,,,<BR>> A tuck to the belly on left rudder {or both depending on how tail heavy} <BR>> more tail heavy more tuck ,,pull in both up and down lines ,,,So now we <BR>> add down thrust to fix one problem upline pull { as as Jim and others <BR>> observed and suggested } and it magnifies the others. like Nat explained <BR>> to Chad ,,,and now it may give a differential problem . so we address <BR>> that with the radio.by mixing<BR>> and this occurs,,<BR>> stalls may be hard to do because,, "mix dont go away ", Snaps and spins <BR>> are hard to perform correctly start,,stop consistently ,and they wander <BR>> off line in the uplines,and 4/5`s so you see flyers using opposite rudder <BR>> to lead before, and after to keep them on line , and even more apparently <BR>> worse in a upline ,,, you can`t convince these guys that it`s possible
<BR>> to do a snap without displacing or tucking ect, because they have never <BR>> experienced it. and it supports their lack of trimming skills<BR>> or a poor design ,Sorry Guys!!<BR>><BR>><BR>> ,,BTW contrary to popular belief nose heavy airplanes {weight forward } <BR>> snap better, lands the snap cleaner, and is perfectly consistently ,stays <BR>> on line way better , { do you have an airplane you have to lead to <BR>> stop ,,its because it does not recover from the stalled condition its <BR>> probably tail heavy } a nose heavy { weight forward} set up stops <BR>> instantly . providing you have the right inputs.<BR>><BR>> In windy weather the 0-0 or sub 1/2 Pos. airplane moves all over the <BR>> place and is not solid at all. its not directionally stable , because of <BR>> the tail weight needed to induce the pos inc in the wing.<BR>> a positive set up will actually weather vein into the wind by itself and <BR>> you
will need opposite rudder to maintain the line sometimes ,,in other <BR>> words it will self correct in the wind ,,this makes it much easier to fly <BR>> in windy weather.<BR>> now ,,,<BR>> every year designers go back to the drawing boards and play with <BR>> airfoils, tail moments ,,tail size ,,,hocus pocus ,,ect all in an attempt <BR>> to fix a trim problem.,, not a design problem.<BR>><BR>> Now to this,,, to correctly trim a model you need three tools,<BR>><BR>> #1 an incidence meter no matter what kind dig. may be better,,<BR>> #2 honesty without it you will deceive yourself into believing it`s <BR>> trimmed<BR>> #3 patience ,,,,I know I just lost some of you But ,<BR>> there is only one of these three you can do without ,,, it`s the inc. <BR>> meter,, the other two will guide you if you stay at it till it`s right.<BR>><BR>> Now the Hebert triangulation Method<BR>> assuming everything else is perfectly straight and
aligned correctly ,,, <BR>> this is a big assumption , but,set your c/g according to the design spec <BR>> on the drawings for your design as a starting point ,,,if you don`t have <BR>> a C/G spec contact Nat Penton, he will give you a great formula he has <BR>> worked up.<BR>> # 1 set motor at 1/2 deg down ..neg inc.<BR>> wings at 1/2 pos to start ,,,this is not a hard deck<BR>> stabs at 1/4 pos because this is about where you will end up.<BR>> Line up all your control surfaces get them even, because we are going to <BR>> let the airplane tell us what to do to fix it later<BR>><BR>> #2 fly the airplane trim hands off level flight,, don`t cheat ,,{I know a <BR>> lot of guys use a little down trim in upright flight to help with upline <BR>> pulls} it has to be hands off perfect then fly inverted to see if you <BR>> like the inverted elevator and the airplane feels solid and easy to hold <BR>> on a line . and then take
notes.<BR>> #3 pull a vertical line see what it does<BR>> #4 put it straight down see how long it takes to pull out to the canopy<BR>> #5 do a left rudder knife edge ,see if it`s straight no pull the entire <BR>> length of the field don`t cheat,,<BR>> #6do a right rudder knife edge see if it`s straight same as above.<BR>> This is the triangulation method I use to diagnose all trim problems with <BR>> any airplane I-MAC to pattern ,,wings are wings.<BR>><BR>> #7 now land and see where the elevator wound up ,,,never mind the stabs <BR>> right now, we will adjust them later.<BR>> take notes of what the airplane did in all these three maneuvers, you <BR>> will see you can triangulate a common input fix, I find it help full to <BR>> have a buddy to help remember whats happening in the air.<BR>> Look at the elevator trim and see what it has in it, if we are lucky and <BR>> your airplane is 10 pounds you are "all over it" and it just
may take a <BR>> little c/g to give a click or two one way or the other.<BR>> #1 But, if it pulls in the up lines and downline you need more pos inc <BR>> one turn at a time on the adjuster ,,<BR>> As an aside ,,,,if you have rear adjusters take them out and put pins and <BR>> donuts make sure they do not move at all as this will mess with the trim <BR>> process ,,I find the rear adjusters being a different distance for the <BR>> wing tube take different amounts of turns to be equal and the wings have <BR>> to adjust perfectly and lock exactly. no warp in the root., yes it <BR>> happens and gives you a false reading.<BR>><BR>> #2 if it goes to the belly in left rudder move the c/g forward{ your tail <BR>> heavy} untill it stops pulling to the belly regardless of the inc.<BR>> if it goes to the canopy in both knifes #1 will probably fix it <BR>> but<BR>> refer to the inverted flight part of you notes and see if you<BR>> think
the elevator was mushy ,hold able but mushy and you might<BR>> require tail weight. and pos inc. to fix both problems canopy pull <BR>> downlines and knife edge flight.<BR>><BR>> Because we are on the edge of trim perfection now in all wing loaded, and <BR>> unloaded ,positions now we can adjust c/g by using the earlier mentioned <BR>> bullet points for fine tune feeling<BR>> Remember most of the time one fix will fix 3other things and bring it all <BR>> together because they are all related, thats why a well trimmed airplane <BR>> rolls with ease and 4 points with ease. because we are not fighting any <BR>> adverse trim issues in any axis. or wing load<BR>><BR>> Now do the adjustments and leave the trims on the airplane like they are<BR>> make another flight your adjustments should Jive with the reverse of what <BR>> you trimmed on the first flight and make your trims work ,,, if you have <BR>> to increase the trim you already
have in there from the first flight LAND <BR>> you went the wrong way with the adjustments and make your corrections <BR>> again<BR>><BR>> < on another side note > for my designs since I know where they should be <BR>> set ,a quick method is to do the triangulation method this way ,, trim <BR>> the airplane to fly the down lines,,, leave this trim in and land ,,<BR>> then adjust the wings to get the trim out and all three Maneuvers are now <BR>> happy,,,<BR>><BR>> The closer you get to the end, the finer the tuning will need to be, and <BR>> it can try your patience<BR>> make sure the tank is centered on the c/g or you will have trim changes <BR>> during the flight as the tank drains<BR>><BR>> don`t get mad at me if you cannot fix your favorite airplane Just buy a <BR>> better design ,,,,Mine preferably <G><BR>> there is so much more that I could add But I`ll leave it alone for another <BR>> post.<BR>> However
I would like to add this ,,<BR>> I agree with Nat that add on T wings are smoke and mirrors However who is <BR>> going to argue with the word Champion ,,<BR>> yes it does work ,,somewhat, it reduces the required rudder angle needed <BR>> to hold knife edges which will in fact reduce mix ,,less rudder less mix <BR>> ,, A POS setup needs none of this.<BR>> Hope this helped ,,you may need to read it twice to absorb it all<BR>> thanks for your interest ,However Brian Clemons is mad at me because I was <BR>> supposed to be painting his airplane tonight LOL<BR>> Bryan<BR>><BR>> Chris F. if you Like you can clean this up and include it for a k-factor <BR>> issue<BR>><BR>><BR>><BR>><BR>><BR>><BR>><BR>><BR>> ---- Don Ramsey <DONRAMSEY@GMAIL.COM>wrote:<BR>>> I'm with Jim in not understand the reason some of the incidence changes<BR>>> work. Consider increasing the incidence for adjusting the push to the
<BR>>> belly<BR>>> in knife edge. My reasoning would be; increase the incidence, put in <BR>>> some<BR>>> down elevator to fly straight and level. Roll to knife edge and the <BR>>> model<BR>>> would then push to the belly more severely. What am I missing?<BR>>><BR>>> Don<BR>>><BR>>> -----Original Message-----<BR>>> From: nsrca-discussion-bounces@lists.nsrca.org<BR>>> [mailto:nsrca-discussion-bounces@lists.nsrca.org] On Behalf Of James <BR>>> Oddino<BR>>> Sent: Tuesday, March 11, 2008 10:59 AM<BR>>> To: NSRCA Mailing List<BR>>> Subject: Re: [NSRCA-discussion] the joy of trimming , left rudder tuck<BR>>> downline pulls<BR>>><BR>>> Bryan,<BR>>><BR>>> I'm trying to figure out how increasing the wing incidence, I assume<BR>>> with respect to the fuselage, will get rid of a pull to the canopy on<BR>>> a vertical downline. Is it because you
need to crank in some down<BR>>> trim to make it fly level? Or is it because the tail flies higher in<BR>>> level flight and the higher vertical cg creates a couple pushing the<BR>>> nose down during the vertical downline?<BR>>><BR>>> I assume that if one could achieve a good vertical downline with power<BR>>> off, he could then adjust the thrust to get a good vertical upline?<BR>>> It would seem that the thrust is part of what made it fly level and<BR>>> you would get into an endless loop chasing things around. What is the<BR>>> sequence for getting what you want?<BR>>><BR>>> I adjust the relation between the downthrust and wing to get a good<BR>>> vertical upline and trim out the pull in the downline like Chad. Tell<BR>>> us how we can get a combination of vertical up with power, level with<BR>>> power (less power?) and vertical down without power that are all good<BR>>> without
throttle to elevator trim.<BR>>><BR>>> Jim O<BR>>><BR>>><BR>>> On Mar 10, 2008, at 5:31 PM, <SHINDEN1@COX.NET><SHINDEN1@COX.NET><BR>>> wrote:<BR>>><BR>>> > Chad having a small tuck to the belly on left rudder only,,<BR>>> > is always a result in a little too much tail weight ,,providing<BR>>> > the stab halves and elevator halves are correct.<BR>>> > thats whats happening in your wandering 4/5`s<BR>>> > the tail weight as is ,,is making you add a little down elevator<BR>>> > trim because the wing is flying a little more positive.<BR>>> > You want to create the pos angle of attack with the wing only use<BR>>> > the tail weight only to adjust the feel for rolls and inverted flight.<BR>>> > engine thrust is contributory But ,not doing anything in the left<BR>>> > knife edge.<BR>>> > it would be happening in the right rudder
too.<BR>>> > sorry Nat..<BR>>> > approach it like this, before you reset the down thrust ,,,because<BR>>> > we want to know what really fixed it<BR>>> > increase the wing inc 1/32 " more positive or till it stopps<BR>>> > pulling in the downline , some airplane require the wing more than<BR>>> > 1/2 deg depending on weight and airfoils 1/2 pos. is not a hard<BR>>> > deck and you will have to move the cg forward to remove the left<BR>>> > rudder knife mix ,,move it till you find a sweet spot , between<BR>>> > downlines and both knife edges.<BR>>> > , Always remember tail heavy makes the elevator and rudder<BR>>> > sensitive and nose wweightmakes them a little numb but much more<BR>>> > effective<BR>>> > your spins,snaps entry and exits ,, up and downline,45`s will be<BR>>> > corrected<BR>>> > you will also see improvement in the wind due to
the forward c/g and<BR>>> > pos inc. add pos wing inc till it stops pulling to the canopy in the<BR>>> > downs<BR>>> > and let us know what happens<BR>>> > Bryan<BR>>> > darn now I have given away the family secrets ,And<BR>>> > I have just made it harder to beat Chad <G><BR>>> ><BR>>> > ---- Nat Penton <NATPENTON@CENTURYTEL.NET>wrote:<BR>>> >> Chad<BR>>> >> Your problem is caused by the large difference between T/L and<BR>>> >> wing. Reduce<BR>>> >> the downthrust by 1 deg and reduce the wing incidence by 1 deg ,<BR>>> >> and test.<BR>>> >><BR>>> >> We will go from there.<BR>>> >><BR>>> >> Your excess downthrust requires up elev trim when under power. You<BR>>> >> need to<BR>>> >> adjust wing and T/L to avoid other problems. If you just lower the<BR>>> >> wing
inc<BR>>> >> it will go to the belly in knife. If you just reduce the D/T it<BR>>> >> will go to<BR>>> >> the canopy in<BR>>> >> knife. Nat<BR>>> >><BR>>> >> ----- Original Message -----<BR>>> >> From: "Chad Northeast" <CHADNORTHEAST@SHAW.CA><BR>>> >> To: "NSRCA Mailing List" <NSRCA-DISCUSSION@LISTS.F3A.US><BR>>> >> Sent: Monday, March 10, 2008 4:57 PM<BR>>> >> Subject: Re: [NSRCA-discussion] the joy of trim<BR>>> >><BR>>> >><BR>>> >>> Ok you trim masters, here is a tricky one for you.<BR>>> >>><BR>>> >>> Bryan and I have been through this a bit last year but I ran out<BR>>> >>> of time<BR>>> >>> before the Worlds to fix it and just flew with what I had.<BR>>> >>><BR>>> >>> On my Twister I have this pesky problem, the setup is
like so,<BR>>> >>><BR>>> >>> wing = 1/2+ Bryans suggestion and I like it<BR>>> >>> stab = 0<BR>>> >>> motor = factory claims 2.5 down, have not measured but could if<BR>>> >>> asked, I<BR>>> >>> have added more to cure a problem see below<BR>>> >>> CG = has been anywhere from 275 to 300mm from TE mostly with the<BR>>> >>> same<BR>>> >>> result. Currently its around 285-290 and it feels good at that<BR>>> >>> point. 45<BR>>> >>> ups inverted track almost hands off if under enough power.<BR>>> >>><BR>>> >>> Symptoms,<BR>>> >>><BR>>> >>> Plane flies well, at this setup I need 0 mix right rudder to ele<BR>>> >>> in knife,<BR>>> >>> and about 2% up ele with left rudder in knife,<BR>>> >>> about 1/32" down
elevator with idle to fix a downline<BR>>> >>> Added downthrust as the increase in wing inc. and more forward CG<BR>>> >>> really<BR>>> >>> helped the mix in knife and made rollers easier, but forced an<BR>>> >>> increase in<BR>>> >>> downthrust as the plane started pulling to the canopy on uplines.<BR>>> >>> Downline mix remained the same.<BR>>> >>><BR>>> >>> The big problem I cannot resolve is this, a 45 deg down upright<BR>>> >>> (motor at<BR>>> >>> idle) the plane pitches to the belly and will not track on its own<BR>>> >>> for any<BR>>> >>> length of time. If I switch the idle-down mix off its rock solid<BR>>> >>> on that<BR>>> >>> line.<BR>>> >>><BR>>> >>> I am open to all suggestions now that I have a bit of time to
play<BR>>> >>> with<BR>>> >>> this, I hope Bryan chimes in some more as I would like to continue<BR>>> >>> where<BR>>> >>> we left off last fall. If you suggest something I will do my best<BR>>> >>> to give<BR>>> >>> it a go and let you know how it works (provided it doesn't snow!)<BR>>> >>><BR>>> >>> The plane is basically super locked in with this setup, except for<BR>>> >>> the<BR>>> >>> silly 45 down upright, which is a problem in cubans and such.<BR>>> >>><BR>>> >>> Comments and thoughts from the masters are most appreciated :) I<BR>>> >>> consider<BR>>> >>> myself one of the, cant really trim that well but can fly through<BR>>> >>> it just<BR>>> >>> fine types :)<BR>>> >>><BR>>> >>> Chad<BR>>>
>>><BR>>> >>> _______________________________________________<BR>>> >>> NSRCA-discussion mailing list<BR>>> >>> NSRCA-discussion@lists.nsrca.org<BR>>> >>> http://lists.nsrca.org/mailman/listinfo/nsrca-discussion<BR>>> >>><BR>>> >><BR>>> >> _______________________________________________<BR>>> >> NSRCA-discussion mailing list<BR>>> >> NSRCA-discussion@lists.nsrca.org<BR>>> >> http://lists.nsrca.org/mailman/listinfo/nsrca-discussion<BR>>> > _______________________________________________<BR>>> > NSRCA-discussion mailing list<BR>>> > NSRCA-discussion@lists.nsrca.org<BR>>> > http://lists.nsrca.org/mailman/listinfo/nsrca-discussion<BR>>><BR>>> _______________________________________________<BR>>> NSRCA-discussion mailing list<BR>>> NSRCA-discussion@lists.nsrca.org<BR>>>
http://lists.nsrca.org/mailman/listinfo/nsrca-discussion<BR>>><BR>>> _______________________________________________<BR>>> NSRCA-discussion mailing list<BR>>> NSRCA-discussion@lists.nsrca.org<BR>>> http://lists.nsrca.org/mailman/listinfo/nsrca-discussion<BR>> _______________________________________________<BR>> NSRCA-discussion mailing list<BR>> NSRCA-discussion@lists.nsrca.org<BR>> http://lists.nsrca.org/mailman/listinfo/nsrca-discussion <BR><BR>_______________________________________________<BR>NSRCA-discussion mailing list<BR>NSRCA-discussion@lists.nsrca.org<BR>http://lists.nsrca.org/mailman/listinfo/nsrca-discussion<BR></BLOCKQUOTE><BR><BR><BR><DIV><STRONG><EM><FONT face="comic sans ms" color=#0000bf size=3>Chris </FONT></EM></STRONG></DIV> <DIV> </DIV> <DIV> </DIV> <DIV> </DIV><p> 
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