---------------------------------------------------------- KIS-List Digest Archive --- Total Messages Posted Fri 07/02/10: 1 ---------------------------------------------------------- Today's Message Index: ---------------------- 1. 05:42 AM - Re: Re: KIS IT-1 Aerodynamics (Richard Trickel) ________________________________ Message 1 _____________________________________ Time: 05:42:41 AM PST US From: Richard Trickel Subject: Re: KIS-List: Re: KIS IT-1 Aerodynamics Mark/OC Many years ago I had Dave Morris do some flight test on my plane for possib le cert ideas.- he did a lot of testing and one included long tuffs at th e wing root and outboard about 2 feet.- These were video taped and showed that in ground affect the tuffs actually were just rising over the stab. -- This only happened in ground affet and not in stall at altitude.-w e felt that part of the problem was the fact that the wing and horiz were a t different angles than the production planes so this was-causing the pro blem.- Though never tested the same way it seemed that the newer taildrag er we built was much better in ground affect.- Now that I have a little m ore experience and about two MM more knowledge I think the best way to adju st this problem is to move the tail up out of the wings flow. looks like th ree inches would have been perfect.-Sounds a little drastic and not reall y necessary but if I had it to do over kind of thing. The airplane is not i n anyway dangerous the way it is so it is something that doesn=B4t really ne ed to be changed.- The- added fairings of Julien helped and we will fin d out about the Vortex generators soon I hope.- I got to admit that this is the best parts of this forum.- The information provided here is invalu able.- Keep it up and I know there are a few others out there with some i deas so lets get involved Rich --- On Thu, 7/1/10, Mark Kettering wrote: From: Mark Kettering Subject: Re: KIS-List: Re: KIS IT-1 Aerodynamics Hi OC, Good to hear you are not crashing that often anymore. I very much like Stinton's book but it is a bit empirical at times with not a lot of data to back it up.- In any case here is page 171.- With a qu ick scan I did not see more on this subject.- I would still check out the book if you can find it. I am not convinced there is an elevator problem being caused by separation in this area with my aircraft.- I have never had a problem with elevator authority up to stall both in and out of ground effect.- I have not seen the video and am waiting on getting it from Scott.- The one picture I hav e seen did show some turbulence (but it would be guessing to call it separa tion) at the aft wing root.- But the flow over the tail and aft part of t he fuselage still looks good.- Maybe this turbulence is really just the v ery start of the stall?- If that is the case the small root faring may st art the stall.- If so maybe this is not all a bad thing since at the root is the best place for the stall to start. Of course I do want to reduce drag since I NEED to be faster than Scott. Mark Kettering -----Original Message----- >From: bakerocb@cox.net >Sent: Jun 30, 2010 4:18 PM >To: kis-list@matronics.com, lgdavid@roadrunner.com >Subject: Re: KIS-List: Re: KIS IT-1 Aerodynamics > > >6/30/2010 > >Hello Larry, Thanks for the book info -- I'll try to check it out through >our local library inter-library lending system. > >'OC' Baker Says: "The best investment we can make is the time and effort t o >gather and understand knowledge." > >======================== >----- Original Message ----- >From: "Larry David" >To: >Sent: Wednesday, June 30, 2010 1:40 PM >Subject: Re: KIS-List: Re: KIS IT-1 Aerodynamics > > >Julian Bone, as part of his research and testing, came up with a book by >Stinton.- Page 171 really told the story about our problem and gave the >formula for the correct wing fairing curve ,, 8 inch radius as I recall. >The title and ISBN are: The Design of the Airplane (9781563475146) by >Stinton, Darrol. > >I bought a copy and loaned it to a fellow with a Glassair so he could desi gn >his wing fairing. Julian did some really good work on the low speed >stability problem.- Pictures of his plane with the new wing fairing are on >Bob's web site as I recall. > >Larry > >======================== == > > >- ----- Original Message ----- >- From: bakerocb@cox.net >- To: "MATRONICS KIS-LIST" , "Larry David" > >- Sent: Wednesday, June 30, 2010 7:12:46 AM GMT -05:00 US/Canada Eastern >- Subject: KIS-List: Re: KIS IT-1 Aerodynamics > >- 6/30/2010 > >- Hello Larrry, You wrote: > >- 1) "I wonder if there is a formula for computing the location of the >vortex >- generator like there is for >- the wing fairing." > >- What wing fairing formula are you referring to? I suspect that the >location >- of the vortex generators on the fuselage sides in front of the wing is >based >- on the TLAR formula followed by lots of inflight testing -- that is th e >- formula that I am using. > >- 2) "It looks like a step. I wonder how many times someone will step on it >by >- mistake." > >- It does have words like "NO STEP" painted on it. Haven't seen any brok en >off >- stubs yet. > >- 3) "I will be interested in reading the results of your testing." > >- Please don't hold your breath while waiting. I've made only two or thr ee >- flights with them on so far and they have been moved between flights a t >- least once. Any results will be very subjective since A) I don't have any >- means (yarn tufts and video camera) to visually to gather persisting d ata >- and B) I can't consistently land the plane the same way each time I tr y. > >- Right now I am involved / distracted by testing some repositioning of my >- center stop spring bias pitch trim actuator. There is not enough trave l in >- the Ray Allen trim motor to handle the entire range of pitch trim need ed >so >- I was using a bent aluminum tab taped to the elevator to give me enoug h >nose >- down trim at aft CG location conditions. A fellow aviator took excepti on >to >- the lack of elegance to that approach and shamed me into trying again to >- solve that lack of pitch trim range with a different approach. (I trie d to >- convince him that any homebuilt worthy of its name had some (duct) tap e on >- it some place, but he wasn't buying that.) My initial repositioning >attempt >- flown yesterday was not successful. > >- 'OC' Baker Says: "The best investment we can make is the time and effo rt >to >- gather and understand knowledge." > >- PS: There is a third solution to the intermittent burble flowing back to >the >- horizontal tail surfaces from the pinched in wing to fuselage juncture >that I failed to mention in >- the email that you quoted from below. That solution is to carry a bit of >- engine power above idle. My attempts to use that technique have always >- resulted in excess float in ground effect down the runway after the >landing >- flare. > >- ======================= ======== >- ----- Original Message ----- >- From: "Larry David" >- To: >- Sent: Wednesday, June 30, 2010 12:14 AM >- Subject: Re: KIS IT-1 Aerodynamics > > >- OC, I see it clearer now from the cirrus pictures.- I wonder if ther e is a >- formula for computing the location of the vortex generator like there is >for >- the wing fairing.- It looks like a step. I wonder how many times som eone >- will step on it by mistake.- :-)- I will be interested in reading the >- results of your testing.- Larry > > =0A=0A=0A ------------------------------------------------------------------------------------- Other Matronics Email List Services ------------------------------------------------------------------------------------- Post A New Message kis-list@matronics.com UN/SUBSCRIBE http://www.matronics.com/subscription List FAQ http://www.matronics.com/FAQ/KIS-List.htm Web Forum Interface To Lists http://forums.matronics.com Matronics List Wiki http://wiki.matronics.com Full Archive Search Engine http://www.matronics.com/search 7-Day List Browse http://www.matronics.com/browse/kis-list Browse Digests http://www.matronics.com/digest/kis-list Browse Other Lists http://www.matronics.com/browse Live Online Chat! http://www.matronics.com/chat Archive Downloading http://www.matronics.com/archives Photo Share http://www.matronics.com/photoshare Other Email Lists http://www.matronics.com/emaillists Contributions http://www.matronics.com/contribution ------------------------------------------------------------------------------------- These Email List Services are sponsored solely by Matronics and through the generous Contributions of its members.