Today's Message Index:
----------------------
1. 06:05 AM - Re: Re: KIS IT-1 Aerodynamics (Galin Hernandez)
2. 08:33 AM - Re: Re: KIS IT-1 Aerodynamics (Rob)
3. 08:43 AM - KIS Aerodynamics ()
4. 09:20 AM - Re: Re: KIS IT-1 Aerodynamics ()
5. 03:41 PM - Re: Re: KIS IT-1 Aerodynamics (Mark Kettering)
6. 08:20 PM - Re: Re: KIS IT-1 Aerodynamics (Galin Hernandez)
Message 1
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Subject: | Re: KIS IT-1 Aerodynamics |
I placed the VG's on the underside of the tail and it worked wonders. Now I
can "squeak" it in once in a while. The airplane feels a lot more stable as
I approach, in the flare as well as in slow flight. I highly recommend them
to those that are already flying. Rich saw them just after I installed them
and made the 1st few test flights.
Galin
N819PR
On Fri, Jul 2, 2010 at 7:28 AM, Richard Trickel
<richard_trickel@yahoo.com>wrote:
> Mark/OC
> Many years ago I had Dave Morris do some flight test on my plane for
> possible cert ideas. he did a lot of testing and one included long tuffs
at
> the wing root and outboard about 2 feet. These were video taped and show
ed
> 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. we felt
> that part of the problem was the fact that the wing and horiz were at
> different angles than the production planes so this was causing the
> problem. Though never tested the same way it seemed that the newer
> taildrager we built was much better in ground affect. Now that I have a
> little more experience and about two MM more knowledge I think the best w
ay
> to adjust this problem is to move the tail up out of the wings flow. look
s
> like three inches would have been perfect. Sounds a little drastic and no
t
> really necessary but if I had it to do over kind of thing. The airplane i
s
> not in anyway dangerous the way it is so it is something that doesn=B4t r
eally
> need 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 invaluabl
e.
> Keep it up and I know there are a few others out there with some ideas so
> lets get involved
> Rich
> --- On *Thu, 7/1/10, Mark Kettering <mantafs@earthlink.net>* wrote:
>
>
> From: Mark Kettering <mantafs@earthlink.net>
>
> Subject: Re: KIS-List: Re: KIS IT-1 Aerodynamics
> To: kis-list@matronics.com
> Date: Thursday, July 1, 2010, 9:08 PM
>
>
> 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 n
ot
> a lot of data to back it up. In any case here is page 171. With a quick
> scan I did not see more on this subject. I would still check out the boo
k
> if you can find it.
>
> I am not convinced there is an elevator problem being caused by separatio
n
> 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 have se
en
> did show some turbulence (but it would be guessing to call it separation)
at
> the aft wing root. But the flow over the tail and aft part of the fusela
ge
> still looks good. Maybe this turbulence is really just the very start of
> the stall? If that is the case the small root faring may start the stall
.
> If so maybe this is not all a bad thing since at the root is the best pla
ce
> 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<http://us.mc1107.mail.yahoo.com/mc/compose?to=b
akerocb@cox.net>
> >Sent: Jun 30, 2010 4:18 PM
> >To: kis-list@matronics.com<http://us.mc1107.mail.yahoo.com/mc/compose?to
=kis-list@matronics.com>,
> lgdavid@roadrunner.com<http://us.mc1107.mail.yahoo.com/mc/compose?to=lg
david@roadrunner.com>
> >Subject: Re: KIS-List: Re: KIS IT-1 Aerodynamics
> >
yahoo.com/mc/compose?to=bakerocb@cox.net>
> >
> >
> >6/30/2010
> >
> >Hello Larry, Thanks for the book info -- I'll try to check it out throug
h
> >our local library inter-library lending system.
> >
> >'OC' Baker Says: "The best investment we can make is the time and effort
> to
> >gather and understand knowledge."
> >
> >========================
> >----- Original Message -----
> >From: "Larry David" <lgdavid@roadrunner.com<http://us.mc1107.mail.yahoo.
com/mc/compose?to=lgdavid@roadrunner.com>
> >
> >To: <kis-list@matronics.com<http://us.mc1107.mail.yahoo.com/mc/compose?t
o=kis-list@matronics.com>
> >
> >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
> design
> >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<http://us.mc1107.mail.yahoo.com/mc/compose?to
=bakerocb@cox.net>
> > To: "MATRONICS KIS-LIST" <kis-list@matronics.com<http://us.mc1107.mail
.yahoo.com/mc/compose?to=kis-list@matronics.com>>,
> "Larry David"
> ><lgdavid@roadrunner.com<http://us.mc1107.mail.yahoo.com/mc/compose?to=
lgdavid@roadrunner.com>
> >
> > 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
> data
> > 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" <lgdavid@roadrunner.com<http://us.mc1107.mail.yaho
o.com/mc/compose?to=lgdavid@roadrunner.com>
> >
> > To: <bakerocb@cox.net<http://us.mc1107.mail.yahoo.com/mc/compose?to=
bakerocb@cox.net>
> >
> > 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 there
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 someo
ne
> > will step on it by mistake. :-) I will be interested in reading the
> > results of your testing. Larry
> >
> >
> >
> >
> >
> >
> >
> >
>
>
> *
>
===========
>
===========
===========
===========
>
> *
>
>
Message 2
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|
Subject: | Re: KIS IT-1 Aerodynamics |
Galin, do you have any pictures of the plane and the VG's on it?
Rob
Galin Hernandez <galinhdz@gmail.com> wrote:
>
>I placed the VG's on the underside of the tail and it worked wonders. Now I
>can "squeak" it in once in a while. The airplane feels a lot more stable as
>I approach, in the flare as well as in slow flight. I highly recommend them
>to those that are already flying. Rich saw them just after I installed them
>and made the 1st few test flights.
>
>Galin
>N819PR
>
>On Fri, Jul 2, 2010 at 7:28 AM, Richard Trickel
><richard_trickel@yahoo.com>wrote:
>
>> Mark/OC
>> Many years ago I had Dave Morris do some flight test on my plane for
>> possible cert ideas. he did a lot of testing and one included long tuffs at
>> the 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. we felt
>> that part of the problem was the fact that the wing and horiz were at
>> different angles than the production planes so this was causing the
>> problem. Though never tested the same way it seemed that the newer
>> taildrager we built was much better in ground affect. Now that I have a
>> little more experience and about two MM more knowledge I think the best way
>> to adjust this problem is to move the tail up out of the wings flow. looks
>> like three inches would have been perfect. Sounds a little drastic and not
>> really necessary but if I had it to do over kind of thing. The airplane is
>> not in anyway dangerous the way it is so it is something that doesnt really
>> need to be changed. The added fairings of Julien helped and we will find
>> 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 invaluable.
>> Keep it up and I know there are a few others out there with some ideas so
>> lets get involved
>> Rich
>> --- On *Thu, 7/1/10, Mark Kettering <mantafs@earthlink.net>* wrote:
>>
>>
>> From: Mark Kettering <mantafs@earthlink.net>
>>
>> Subject: Re: KIS-List: Re: KIS IT-1 Aerodynamics
>> To: kis-list@matronics.com
>> Date: Thursday, July 1, 2010, 9:08 PM
>>
>>
>> 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 quick
>> 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 have seen
>> did show some turbulence (but it would be guessing to call it separation) at
>> the aft wing root. But the flow over the tail and aft part of the fuselage
>> still looks good. Maybe this turbulence is really just the very start of
>> the stall? If that is the case the small root faring may start 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<http://us.mc1107.mail.yahoo.com/mc/compose?to=bakerocb@cox.net>
>> >Sent: Jun 30, 2010 4:18 PM
>> >To: kis-list@matronics.com<http://us.mc1107.mail.yahoo.com/mc/compose?to=kis-list@matronics.com>,
>> lgdavid@roadrunner.com<http://us.mc1107.mail.yahoo.com/mc/compose?to=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
>> to
>> >gather and understand knowledge."
>> >
>> >========================> >----- Original Message -----
>> >From: "Larry David" <lgdavid@roadrunner.com<http://us.mc1107.mail.yahoo.com/mc/compose?to=lgdavid@roadrunner.com>
>> >
>> >To: <kis-list@matronics.com<http://us.mc1107.mail.yahoo.com/mc/compose?to=kis-list@matronics.com>
>> >
>> >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
>> design
>> >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<http://us.mc1107.mail.yahoo.com/mc/compose?to=bakerocb@cox.net>
>> > To: "MATRONICS KIS-LIST" <kis-list@matronics.com<http://us.mc1107.mail.yahoo.com/mc/compose?to=kis-list@matronics.com>>,
>> "Larry David"
>> ><lgdavid@roadrunner.com<http://us.mc1107.mail.yahoo.com/mc/compose?to=lgdavid@roadrunner.com>
>> >
>> > 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 the
>> > 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 broken
>>
>> >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 three
>> > flights with them on so far and they have been moved between flights at
>> > 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
>> data
>> > and B) I can't consistently land the plane the same way each time I try.
>> >
>> > Right now I am involved / distracted by testing some repositioning of my
>> > center stop spring bias pitch trim actuator. There is not enough travel
>> in
>> > the Ray Allen trim motor to handle the entire range of pitch trim needed
>>
>> >so
>> > I was using a bent aluminum tab taped to the elevator to give me enough
>> >nose
>> > down trim at aft CG location conditions. A fellow aviator took exception
>>
>> >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 tried
>> to
>> > convince him that any homebuilt worthy of its name had some (duct) tape
>> 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 effort
>>
>> >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" <lgdavid@roadrunner.com<http://us.mc1107.mail.yahoo.com/mc/compose?to=lgdavid@roadrunner.com>
>> >
>> > To: <bakerocb@cox.net<http://us.mc1107.mail.yahoo.com/mc/compose?to=bakerocb@cox.net>
>> >
>> > 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 there 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 someone
>> > will step on it by mistake. :-) I will be interested in reading the
>> > results of your testing. Larry
>> >
>> >
>> >
>> >
>> >
>> >
>> >
>> >
>>
>>
>> *
>>
>===========
>>
>===========
>===========
>===========
>>
>> *
>>
>>
Message 3
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|
Subject: | KIS Aerodynamics |
7/3/2010
Hello Galin, You are flying a four place Cruiser / KIS TR-4 aren't you?
I would expect that the aerodynamic performance of the 2 place and the 4
place KIS airplanes may be a bit different and should be taken into account
in any discussions or modifications.
'OC' Baker Says: "The best investment we can make is the time and effort to
gather and understand knowledge."
====================================================
----- Original Message -----
From: "Galin Hernandez" <galinhdz@gmail.com>
Sent: Saturday, July 03, 2010 9:04 AM
Subject: Re: KIS-List: Re: KIS IT-1 Aerodynamics
I placed the VG's on the underside of the tail and it worked wonders. Now I
can "squeak" it in once in a while. The airplane feels a lot more stable as
I approach, in the flare as well as in slow flight. I highly recommend them
to those that are already flying. Rich saw them just after I installed them
and made the 1st few test flights.
Galin
N819PR
=============================================================
On Fri, Jul 2, 2010 at 7:28 AM, Richard Trickel
<richard_trickel@yahoo.com>wrote:
> Mark/OC
> Many years ago I had Dave Morris do some flight test on my plane for
> possible cert ideas. he did a lot of testing and one included long tuffs
> at
> the 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. we felt
> that part of the problem was the fact that the wing and horiz were at
> different angles than the production planes so this was causing the
> problem. Though never tested the same way it seemed that the newer
> taildrager we built was much better in ground affect. Now that I have a
> little more experience and about two MM more knowledge I think the best
> way
> to adjust this problem is to move the tail up out of the wings flow. looks
> like three inches would have been perfect. Sounds a little drastic and not
> really necessary but if I had it to do over kind of thing. The airplane is
> not in anyway dangerous the way it is so it is something that doesnt
> really
> need to be changed. The added fairings of Julien helped and we will find
> 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
> invaluable.
> Keep it up and I know there are a few others out there with some ideas so
> lets get involved
> Rich
Message 4
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|
Subject: | Re: KIS IT-1 Aerodynamics |
7/3/2010
Hello Mark, Thanks for your reply, the good wishes, and the page from
Stinton's book. You wrote:
1) "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."
We may not understand completely what is going on pitch wise in the landing
flare and ground effect with the KIS TR-1, but it would seem that enough
pilots have reported enough surprises / problems in this arena that we:
A) Don't have a firm grasp on the nature of what is happening in this arena;
B) Don't have agreement on the existence or extent of the surprises /
problems in this arena; and C) Don't have agreement on whether a solution is
required or what that solution should be.
I do agree with Rich that the problem is not dangerous, but I am still a bit
annoyed that after flying 50 years plus, 5,000 hours plus over all, and
almost 300 hours in this plane that I can't do a consistent flare and
touchdown on every landing. Further the nose wheel touches down immediately
after the main gear touches down almost every time. On a few rare occasions
I have kept the nose wheel from touching down, but when I make a determined
attempt to keep the nose wheel from touching down I am likely to do a little
re airborne skip.
2) "I have not seen the video and am waiting on getting it from Scott."
If my DVD copy efforts have been successful I am willing to make more copies
and send them to interested KIS TR-1 pilots -- this is what Julian had in
mind in sending me the DVD. You will see video of yarn tufts flowing forward
against the direction of travel in the wing to fuselage fillet area. Don't
know what this is doing to the air flow back at the horizontal tail
surfaces, but it can't be all good.
'OC' Baker Says: "The best investment we can make is the time and effort to
gather and understand knowledge."
============================================================
----- Original Message -----
From: "Mark Kettering" <mantafs@earthlink.net>
Sent: Thursday, July 01, 2010 5:08 PM
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
> quick 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 have
> seen did show some turbulence (but it would be guessing to call it
> separation) at the aft wing root. But the flow over the tail and aft part
> of the fuselage still looks good. Maybe this turbulence is really just
> the very start of the stall? If that is the case the small root faring
> may start 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
Message 5
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Subject: | Re: KIS IT-1 Aerodynamics |
Hello OC,
We should also consider that since these planes are home built no two are exactly
alike so they may not have the same exact handling qualities. At times even
production aircraft are not the same. My flight test engineering instructor
once told a story about flight testing Piper Tomahawks. He said no two had the
same spin entry and spin recovery handling. One Tomahawk he flew would recover
from a spin. Another would not.
In any case, I think the holding the nose off when landing after the mains contact
is not really an elevator issue. I think it is a main gear location issue.
I once did a quick calculation and came to the conclusion the main gear is
too far aft. When on the ground the force due to the main gear (an up force that
is aft of the CG) puts a nose down moment on the aircraft making the nose
slam down. Of course the main gear on a trigear plane needs to be aft of the
CG but the more aft it is the larger the nose down moment until it overcome the
maximum nose up moment the horizontal tail can generate.
This too far aft main gear also makes for a potential to over rotate on takeoff.
As the main gear lift off the nose down moment due to the main gear is gone
so if the pilot does not reduce the elevator pitch up as this happens the plane
will pitch up.
There is no reason to live with this issue. Moving the main gear contact point
forward is very simple. I moved my main gear contact point forward by making
a flox wedge between the gear and the fuselage so the main gear is now angled
slightly forward. Not only does this fully eliminate the landing nose slam but
also make the takeoffs much nicer with less pilot effort.
Mark
>
>I do agree with Rich that the problem is not dangerous, but I am still a bit
>annoyed that after flying 50 years plus, 5,000 hours plus over all, and
>almost 300 hours in this plane that I can't do a consistent flare and
>touchdown on every landing. Further the nose wheel touches down immediately
>after the main gear touches down almost every time. On a few rare occasions
>I have kept the nose wheel from touching down, but when I make a determined
>attempt to keep the nose wheel from touching down I am likely to do a little
>re airborne skip.
>
Message 6
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Subject: | Re: KIS IT-1 Aerodynamics |
Rob;
I have two pictures on my web page of the VG's. You can view them at:
http://puertoricoflyer.com/cgi-bin/photoalbum/view_photo/2529251
http://puertoricoflyer.com/cgi-bin/photoalbum/view_photo/2539431
They were not very difficult to install. The instructions were very simple
to follow.
Galin
N819PR
On Sat, Jul 3, 2010 at 10:24 AM, Rob <punchy@frontiernet.net> wrote:
>
> Galin, do you have any pictures of the plane and the VG's on it?
>
> Rob
>
>
> Galin Hernandez <galinhdz@gmail.com> wrote:
> >
> >I placed the VG's on the underside of the tail and it worked wonders. No
w
> I
> >can "squeak" it in once in a while. The airplane feels a lot more stable
> as
> >I approach, in the flare as well as in slow flight. I highly recommend
> them
> >to those that are already flying. Rich saw them just after I installed
> them
> >and made the 1st few test flights.
> >
> >Galin
> >N819PR
> >
> >On Fri, Jul 2, 2010 at 7:28 AM, Richard Trickel
> ><richard_trickel@yahoo.com>wrote:
> >
> >> Mark/OC
> >> Many years ago I had Dave Morris do some flight test on my plane for
> >> possible cert ideas. he did a lot of testing and one included long
> tuffs at
> >> the 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 sta
b.
> >> This only happened in ground affet and not in stall at altitude. we fe
lt
> >> that part of the problem was the fact that the wing and horiz were at
> >> different angles than the production planes so this was causing the
> >> problem. Though never tested the same way it seemed that the newer
> >> taildrager we built was much better in ground affect. Now that I have
a
> >> little more experience and about two MM more knowledge I think the bes
t
> way
> >> to adjust this problem is to move the tail up out of the wings flow.
> looks
> >> like three inches would have been perfect. Sounds a little drastic and
> not
> >> really necessary but if I had it to do over kind of thing. The airplan
e
> is
> >> not in anyway dangerous the way it is so it is something that doesn=B4
t
> really
> >> need to be changed. The added fairings of Julien helped and we will
> find
> >> 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
> invaluable.
> >> Keep it up and I know there are a few others out there with some ideas
> so
> >> lets get involved
> >> Rich
> >> --- On *Thu, 7/1/10, Mark Kettering <mantafs@earthlink.net>* wrote:
> >>
> >>
> >> From: Mark Kettering <mantafs@earthlink.net>
> >>
> >> Subject: Re: KIS-List: Re: KIS IT-1 Aerodynamics
> >> To: kis-list@matronics.com
> >> Date: Thursday, July 1, 2010, 9:08 PM
> >>
> >>
> >> 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 wit
h
> not
> >> a lot of data to back it up. In any case here is page 171. With a
> quick
> >> 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 elevat
or
> >> authority up to stall both in and out of ground effect. I have not se
en
> the
> >> video and am waiting on getting it from Scott. The one picture I have
> seen
> >> did show some turbulence (but it would be guessing to call it
> separation) at
> >> the aft wing root. But the flow over the tail and aft part of the
> fuselage
> >> still looks good. Maybe this turbulence is really just the very start
> of
> >> the stall? If that is the case the small root faring may start 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 Scot
t.
> >>
> >> Mark Kettering
> >>
> >>
> >> -----Original Message-----
> >> >From: bakerocb@cox.net<
> http://us.mc1107.mail.yahoo.com/mc/compose?to=bakerocb@cox.net>
> >> >Sent: Jun 30, 2010 4:18 PM
> >> >To: kis-list@matronics.com<
> http://us.mc1107.mail.yahoo.com/mc/compose?to=kis-list@matronics.com>,
> >> lgdavid@roadrunner.com<
> http://us.mc1107.mail.yahoo.com/mc/compose?to=lgdavid@roadrunner.com>
> >> >Subject: Re: KIS-List: Re: KIS IT-1 Aerodynamics
> >> >
> http://us.mc1107.mail.yahoo.com/mc/compose?to=bakerocb@cox.net>
> >> >
> >> >
> >> >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
> >> to
> >> >gather and understand knowledge."
> >> >
> >> >=======================
=> >----- Original Message -----
> >> >From: "Larry David" <lgdavid@roadrunner.com<
> http://us.mc1107.mail.yahoo.com/mc/compose?to=lgdavid@roadrunner.com>
> >> >
> >> >To: <kis-list@matronics.com<
> http://us.mc1107.mail.yahoo.com/mc/compose?to=kis-list@matronics.com>
> >> >
> >> >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 t
he
> >> >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
> >> design
> >> >his wing fairing. Julian did some really good work on the low speed
> >> >stability problem. Pictures of his plane with the new wing fairing a
re
> on
> >>
> >> >Bob's web site as I recall.
> >> >
> >> >Larry
> >> >
> >> >=======================
===
> >> >
> >> >
> >> > ----- Original Message -----
> >> > From: bakerocb@cox.net<
> http://us.mc1107.mail.yahoo.com/mc/compose?to=bakerocb@cox.net>
> >> > To: "MATRONICS KIS-LIST" <kis-list@matronics.com<
> http://us.mc1107.mail.yahoo.com/mc/compose?to=kis-list@matronics.com>>,
> >> "Larry David"
> >> ><lgdavid@roadrunner.com<
> http://us.mc1107.mail.yahoo.com/mc/compose?to=lgdavid@roadrunner.com>
> >> >
> >> > 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 th
e
> >> >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
> the
> >> > 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
> broken
> >>
> >> >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
> three
> >> > flights with them on so far and they have been moved between flight
s
> at
> >> > least once. Any results will be very subjective since A) I don't ha
ve
> >> any
> >> > means (yarn tufts and video camera) to visually to gather persistin
g
> >> data
> >> > and B) I can't consistently land the plane the same way each time I
> try.
> >> >
> >> > Right now I am involved / distracted by testing some repositioning
of
> my
> >> > center stop spring bias pitch trim actuator. There is not enough
> travel
> >> in
> >> > the Ray Allen trim motor to handle the entire range of pitch trim
> needed
> >>
> >> >so
> >> > I was using a bent aluminum tab taped to the elevator to give me
> enough
> >> >nose
> >> > down trim at aft CG location conditions. A fellow aviator took
> exception
> >>
> >> >to
> >> > the lack of elegance to that approach and shamed me into trying aga
in
> to
> >> > solve that lack of pitch trim range with a different approach. (I
> tried
> >> to
> >> > convince him that any homebuilt worthy of its name had some (duct)
> tape
> >> 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
> effort
> >>
> >> >to
> >> > gather and understand knowledge."
> >> >
> >> > PS: There is a third solution to the intermittent burble flowing ba
ck
> 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 b
it
> 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" <lgdavid@roadrunner.com<
> http://us.mc1107.mail.yahoo.com/mc/compose?to=lgdavid@roadrunner.com>
> >> >
> >> > To: <bakerocb@cox.net<
> http://us.mc1107.mail.yahoo.com/mc/compose?to=bakerocb@cox.net>
> >> >
> >> > 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 the
re
> is
> >> a
> >> > formula for computing the location of the vortex generator like the
re
> is
> >>
> >> >for
> >> > the wing fairing. It looks like a step. I wonder how many times
> someone
> >> > will step on it by mistake. :-) I will be interested in reading t
he
> >> > results of your testing. Larry
> >> >
> >> >
> >> >
> >> >
> >> >
> >> >
> >> >
> >> >
> >>
> >>
> >> *
> >>
> >===========
> >>
> >===========
> >===========
> >===========
> >>
> >> *
> >>
> >>
>
===========
===========
===========
===========
>
>
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