Matronics Email Lists :: View topic - speed and drag reduction

Matronics Email Lists
Web Forum Interface to the Matronics Email Lists

Get Email Distribution Too! FAQ Search Memberlist Usergroups Register

Profile Log in to check your private messages Log in

speed and drag reduction

Matronics Email Lists Forum Index -> Kitfox-List

View previous topic :: View next topic

Author Message

morid(at)northland.lib.mi
Guest

Posted: Fri Jun 30, 2006 12:43 pm Post subject: speed and drag reduction

Kurt, assuming your airspeed is accurate, something is definitely wrong.

The Kitfox5 should be easily capable of 105kt cruise with the power you

have.  Something appears to be holding you back.  My S5 with 100hp normally

aspirated NSI cruises about 94kts at 4gph, 22" MP, and 3900 rpm which isn't

really working very hard.  Maybe just more drag reduction is what you need?

Those flaperons can add a bunch of drag if they're set too low.  Do you have

wheel pants?  They're good for a couple knots.  Lots of little cleanup

things help too like the fuel caps, jury struts, stab struts, etc.

My personal opinion is that weight and drag reduction are the things to put

the most work into if you want an efficient airplane.

Deke

 	  Quote: 	
		   The first 85 knots is easy for me, but the next 15 to

 25 is a struggle.  I have to check, but I think I top

 out around 109 kts now at more than twice the fuel

 flow of 85 kts.

 I am wondering if my flapperons might be adjusted a

 little too low and could use a few degrees up?  Other

 list members said they make a big difference.  I sure

 know the first notch makes 70 kts (max flap speed)

 almost as draggy as 85 kts clean.

 Or it may be my prop, like I said.

 Kurt S.

 --- John Anderson <janderson412(at)hotmail.com> wrote:

 > Yep, I did this too, added a profiled leading edge

 > to start of the vert stab

 > to split the flow. Guess it all helps for as I've

 > said, up to 100kts is

 > relatively easy. Hopefully after increasing the prop

 > pitch and get the boost

 > up a bit at lower RPM I might get a wee bit

 > more..John

 __________________________________________________

- The Matronics Kitfox-List Email Forum -

Use the List Feature Navigator to browse the many List utilities available such as the Email Subscriptions page, Archive Search & Download, 7-Day Browse, Chat, FAQ, Photoshare, and much more:

http://www.matronics.com/Navigator?Kitfox-List

smokey_bear_40220(at)yaho
Guest

Posted: Sun Jul 02, 2006 12:54 pm Post subject: speed and drag reduction

That is what I think to Deke.



I checked my ASI and it was within 2 knots.  That

might have changed a little with the scoop added

because it disturbes the airflow differently behind it

compared to the raw radiator.



I would sure like to see 105 knots at around 4 GPH.  I

burn 5 GPH to get 85 now.  But I purposely started

with no siginificant drag reductions on the plane.  I

wanted to see what each would do as I add them and

report that.  Still have a lot to go.



Library is closing.  Got to go.



Kurt S.



--- Fox5flyer <morid(at)northland.lib.mi.us> wrote:



 	  Quote: 	
		   Kurt, assuming your airspeed is accurate, something

 is definitely wrong......


	


__________________________________________________

- The Matronics Kitfox-List Email Forum -

Use the List Feature Navigator to browse the many List utilities available such as the Email Subscriptions page, Archive Search & Download, 7-Day Browse, Chat, FAQ, Photoshare, and much more:

http://www.matronics.com/Navigator?Kitfox-List

janderson412(at)hotmail.c
Guest

Posted: Sun Jul 02, 2006 8:55 pm Post subject: speed and drag reduction

Could be quite a lot of drag created at the back end of the radiator. I'm 

sure the air behind mine isn't happy as at higher speeds there is quite a 

buffeting vibration, I had an exit cowl but it cracked so raw in that area 

at the moment but intend to build another. John

Reply-To: kitfox-list(at)matronics.com

<smokey_bear_40220(at)yahoo.com>

That is what I think to Deke.

I checked my ASI and it was within 2 knots.  That

might have changed a little with the scoop added

because it disturbes the airflow differently behind it

compared to the raw radiator.

I would sure like to see 105 knots at around 4 GPH.  I

burn 5 GPH to get 85 now.  But I purposely started

with no siginificant drag reductions on the plane.  I

wanted to see what each would do as I add them and

report that.  Still have a lot to go.

Library is closing.  Got to go.

Kurt S.

--- Fox5flyer <morid(at)northland.lib.mi.us> wrote:

 > Kurt, assuming your airspeed is accurate, something

 > is definitely wrong......

__________________________________________________

_________________________________________________________________

- The Matronics Kitfox-List Email Forum -

Use the List Feature Navigator to browse the many List utilities available such as the Email Subscriptions page, Archive Search & Download, 7-Day Browse, Chat, FAQ, Photoshare, and much more:

http://www.matronics.com/Navigator?Kitfox-List

Display posts from previous:

	Matronics Email Lists Forum Index -> Kitfox-List	All times are GMT - 8 Hours
Page 1 of 1

Jump to:

You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot vote in polls in this forum
You cannot attach files in this forum
You can download files in this forum