Matronics Email Lists :: View topic - Low speed takeoffs and stall Airpseed. LRI

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

Low speed takeoffs and stall Airpseed. LRI

Matronics Email Lists Forum Index -> Zenith-List

View previous topic :: View next topic

Author Message

ggower_99(at)yahoo.com
Guest

Posted: Mon Jun 05, 2006 4:14 pm Post subject: Low speed takeoffs and stall Airpseed. LRI

Hello Paul,

   

  I have mine installed in the 701,   Is a diferent type of airplane that the 601, because the 701 has two diferent angle of attack in the wing.  

   

  One without the slots working (normal approach) and another diferent angle of attack in the flare (when the slots beguin to work).   

   

  We use our LRI calibrated at normal approach angle of attack for two reasons:  

   

  First We fly at diferent altitudes here and diferent sizes of landing strips, so a slow aproach without loosing glide angle/speed  is important.

   

  And second the STOL  flair/approach in the 701 is so slow and close to the ground that sincerely,  there is no time to glance at the LRI.  We just keep the eyes on the strip trough the side of the windshield that instant before touch down...  

   

  I am now building a 601  XL  that will also have an LRI installed,   but I am very far from the kit looking as an airplane...

   

  Here is one good article that explains how the LRI works in a "normal" type of wing.  (If there is something close to "normal wing" in modern homebuilt airplanes   

   

  In this article is an instalation in a RV6.  

  Very similar way,  was how it was explained to me by a local bush pilot that has one installed in his airplane and talked me to install one.

   

  http://home.hiwaay.net/~sbuc/journal/liftreserve-pg2.htm

   

  Hope this helps.  Because I am sure that the XL can make impressive short field landings in grass strips if flow correctly...  Time will say  (in my case).

   

  Saludos

  Gary Gower.



Paul Mulwitz <p.mulwitz(at)worldnet.att.net> wrote:

  [quote]--> Zenith-List message posted by: Paul Mulwitz 

 	  Quote: 	
		  My Lift Reserve indicator comes up sooner, and I do pay attention to 

that, but anyone know of an airspeed indicator that is more 

sensitive at the slower speeds?


	


I have installed a Lift Reserve Indicator in my XL, but I am a long 

way from flying. I want to ask you about your experience with this 

device. With it working at low speeds, why do you want a low speed 

airspeed indicator? Is the LRI sufficient to tell you when to 

rotate? Perhaps this is just a matter of having a backup indication.



Paul

XL wings.

do not

p.mulwitz(at)worldnet.att
Guest

Posted: Mon Jun 05, 2006 6:03 pm Post subject: Low speed takeoffs and stall Airpseed. LRI

Hi Gary,



 Thank you for the article link on flying the LRI.  I enjoyed reading it and got my ideas about it reinforced.  It sounds to me like a much better instrument to use for critical airspeed control than the airspeed indicator.  Of course you can still use the nose "Picture" on the horizon to control your speed as well, but the LRI sounds like a nice precise way to get nearly maximum performance from your plane on both takeoff and landing.



 I understand your comment about not wanting to take your eyes off the runway on landing approach to check the LRI.  There may be several ways to deal with this problem.  Let me suggest a few:



 1.  You can set up your approach at the desired LRI indication.  Then look at the pitch on the nose of your plane and hold the same pitch while using the same power/airspeed and flap setting.  This should hold the same LRI indication.



 2.  I have seen many AOA indicators - particularly the kind with colored lights - mounted above the instrument panel so the indication is easy to see while looking out the windshield.  You could mount your LRI indicator either on top of the panel or at the top-most position in the center of your viewing image.  This would make it very easy to find the indicator at the critical moments.



 3.  If you have already mounted your indicator at a remote location in your instrument panel, you might be able to make an optical path to make it visible from above the panel.  This might be similar to the mirrors used in a "Periscope".  Place one rectangular or oval mirror below the gauge and mount another one above the panel in line with the other mirror.  Then you should be able to see the instrument face while looking out the windshield.



 In any case, I am happy I decided to install one of these instruments in my XL.  I think I will put it on the topmost row of instruments - perhaps right next to the EFIS.



 Thanks again,



 Paul

 XL wings (nearly done)



 

 At 05:13 PM 6/5/2006, you wrote:

  	  Quote: 	
		  Hello Paul,

  

 We use our LRI calibrated at normal approach angle of attack for two reasons:  

  

 First We fly at diferent altitudes here and diferent sizes of landing strips, so a slow aproach without loosing glide angle/speed  is important.

  

 And second the STOL  flair/approach in the 701 is so slow and close to the ground that sincerely,  there is no time to glance at the LRI.  We just keep the eyes on the strip trough the side of the windshield that instant before touch down... 

  

 I am now building a 601  XL  that will also have an LRI installed,   but I am very far from the kit looking as an airplane...

  

 Here is one good article that explains how the LRI works in a "normal" type of wing.  (If there is something close to "normal wing" in modern homebuilt airplanes   

  

  http://home.hiwaay.net/~sbuc/journal/liftreserve-pg2.htm

  

 Hope this helps.  Because I am sure that the XL can make impressive short field landings in grass strips if flow correctly...  Time will say (in my case).

  

 Saludos

 Gary Gower.

rdewees(at)mindspring.com
Guest

Posted: Mon Jun 05, 2006 6:28 pm Post subject: Low speed takeoffs and stall Airpseed. LRI

Hi Paul and Gary,

I can't speak to the 701 installation of a LRI but have had a LRI in my 

601HDS for almost  a year and a half. I posted pictures of the probe and 

indicator on Scott Laughlin's website and would not fly without it.  My 

field is short and rough and I found that my landings were unnecessarily 

long and fast.  Using the LRI I have shortened the takeoff and landing 

distance and cut down considerably on wear and tear on the plane and my 

nerves.  I highly reccomend one.

     As far as being too busy to look at one while close to the ground I 

found that it's THE most important instrument to look at close to the 

ground.  I mounted mine above the instrument panel so it's in my line of 

sight as I look out the canopy.  A few ex-military pilots recognize it 

but almost all GA pilots are clueless as to it's function untill they 

see it in action.  Total cost was less than $80 or so.  Only downside is 

that the Dwyer differential pressure gauge used on mine as in indicator 

is an odd size-- I guess 3 or 3 1/2 inches so it's hard to put in line 

with other instruments.  I have seen expensive and complex digital 

models that illiminate sequential red or green LEDs but I like the 

analog needle that gives immediate feedback on wing's lift. I installed 

it to let me know when the wing was about to stall so I could land 

slower but found that it's just as handy to lift off short in ground 

effect and watch the lift available rise to a safe level before rotating 

and climbing out  Works just as well to give warning of an impending 

departure stall or if you do a high speed turn or chandelle it lets you 

know what the state of lift remaining is. 

 If you ever fly with one you won't be without one.  Just don't stick it 

in a corner where you can't see it easily. 



Ron



Gary Gower wrote:



 	  Quote: 	
		   Hello Paul,

  

 I have mine installed in the 701,   Is a diferent type of airplane 

 that the 601, because the 701 has two diferent angle of attack in the 

 wing. 

  

 I am now building a 601  XL  that will also have an LRI installed,   

 but I am very far from the kit looking as an airplane...

  

 Hope this helps.  Because I am sure that the XL can make impressive 

 short field landings in grass strips if flow correctly...  Time will 

 say (in my case).

  

 Saludos

 Gary Gower.

jean-paul.roy4(at)tlb.sym
Guest

Posted: Tue Jun 06, 2006 2:17 am Post subject: Low speed takeoffs and stall Airpseed. LRI

Hello all. Just one question. Where can this LRI instrument be bought?



Jean-Paul Roy

just received the wing kit

do not archive

---

p.mulwitz(at)worldnet.att
Guest

Posted: Tue Jun 06, 2006 3:14 am Post subject: Low speed takeoffs and stall Airpseed. LRI

At 03:11 AM 6/6/2006, you wrote:

 	  Quote: 	
		  Hello all. Just one question. Where can this LRI instrument be bought?


	


--

I built mine from plans available on the net.  However, you can also 

buy them as complete systems.  One source I found from a google search:

http://www.liftreserve.com/Faqinst.htm



Paul

XL wings

do not archive

zodierocket(at)hsfx.ca
Guest

Posted: Tue Jun 06, 2006 3:44 am Post subject: Low speed takeoffs and stall Airpseed. LRI

You can build the LRI from Plans I have on www.ch601.org  in the Builder

Resources section. This is an instrument I would never be without. 



Mark Townsend  Alma, Ontario

Zodiac 601XL C-GOXL, CH701 just started

www.ch601.org / www.ch701.com / www.Osprey2.com



--

jean-paul.roy4(at)tlb.sym
Guest

Posted: Tue Jun 06, 2006 4:36 am Post subject: Low speed takeoffs and stall Airpseed. LRI

Thank you kindly Paul



Jean-Paul Roy

do not archive

---

Gig Giacona

Joined: 10 Jan 2006
Posts: 1416
Location: El Dorado Arkansas USA

Posted: Tue Jun 06, 2006 5:40 am Post subject: Re: Low speed takeoffs and stall Airpseed. LRI

I'm a little curious. You've got a Dynon unit right? Is there a reason other than redundancy that you aren't just using the AOA that is part of the unit?



 	  p.mulwitz(at)worldnet.att wrote: 	
		  Hi Gary,



 Thank you for the article link on flying the LRI.? I enjoyed reading it and got my ideas about it reinforced.? It sounds to me like a much better instrument to use for critical airspeed control than the airspeed indicator.? Of course you can still use the nose "Picture" on the horizon to control your speed as well, but the LRI sounds like a nice precise way to get nearly maximum performance from your plane on both takeoff and landing.



 I understand your comment about not wanting to take your eyes off the runway on landing approach to check the LRI.? There may be several ways to deal with this problem.? Let me suggest a few:



 1.? You can set up your approach at the desired LRI indication.? Then look at the pitch on the nose of your plane and hold the same pitch while using the same power/airspeed and flap setting.? This should hold the same LRI indication.



 2.? I have seen many AOA indicators - particularly the kind with colored lights - mounted above the instrument panel so the indication is easy to see while looking out the windshield.? You could mount your LRI indicator either on top of the panel or at the top-most position in the center of your viewing image.? This would make it very easy to find the indicator at the critical moments.



 3.? If you have already mounted your indicator at a remote location in your instrument panel, you might be able to make an optical path to make it visible from above the panel.? This might be similar to the mirrors used in a "Periscope".? Place one rectangular or oval mirror below the gauge and mount another one above the panel in line with the other mirror.? Then you should be able to see the instrument face while looking out the windshield.



 In any case, I am happy I decided to install one of these instruments in my XL.? I think I will put it on the topmost row of instruments - perhaps right next to the EFIS.



 Thanks again,



 Paul

 XL wings (nearly done)



 

 At 05:13 PM 6/5/2006, you wrote:

  	  Quote: 	
		  Hello Paul,

 ?

 We use our LRI calibrated at normal approach angle of attack for two reasons:? 

 ?

 First We fly at diferent altitudes here and diferent sizes of landing strips, so a slow aproach without loosing glide angle/speed? is important.

 ?

 And second the STOL? flair/approach in the 701 is so slow and close to the ground that sincerely,? there is no time to glance at the LRI.? We just keep the eyes on the strip trough the side of the windshield that instant before touch down... 

 ?

 I am now building a 601? XL? that will also have an LRI installed,?? but I am very far from the kit looking as an airplane...

 ?

 Here is one good article that explains how the LRI works in a "normal" type of wing.? (If there is something close to "normal wing" in modern homebuilt airplanes ? 

 ?

  http://home.hiwaay.net/~sbuc/journal/liftreserve-pg2.htm

 ?

 Hope this helps.? Because I am sure that the XL can make impressive short field landings in grass strips if flow correctly...? Time will say (in my case).

 ?

 Saludos

 Gary Gower.

_________________
W.R. "Gig" Giacona
601XL Under Construction
See my progress at www.peoamerica.net/N601WR

JAPhillipsGA(at)aol.com
Guest

Posted: Tue Jun 06, 2006 6:38 am Post subject: Low speed takeoffs and stall Airpseed. LRI

Ron, good to hear from you. I just pulled my DG, vac and all that plumbing from the plane so I have an empty hole in the dash (EHITD) I could fill with an LRI. What kind do you have and how difficult is it to install ? I remember you talking about it when we were flying, but my attention was on your 3300 so I missed some of it. I really don't want to have to take a wing off to install something. Best regards, Bill

 do not archive

rdewees(at)mindspring.com
Guest

Posted: Tue Jun 06, 2006 7:47 am Post subject: Low speed takeoffs and stall Airpseed. LRI

Hi Bill,

 I read your post about the device you made to get under the panel.  That's a great accomplishment.  I couldn't find a shoe horn that large so I just squirm in.  I've spent way too much fun on my back with my feet over my head and it wasnt' even an indecent situation!

   I don't remember the source of the plans for my LRI except that I got them from Scott Laughlin.  I will send him an email and ask him to post the link.  He was turning out the probe ends and mentioned that he was set up to do others so I bought one from him for $40.  I think I could make one now tho.  It's made from alumimum bar stock 1/2 X 1 1/2 inches and about 10 inches long.  THere are two holes drilled lengthwise almost all the way thru the bar but edgewise holes from the front are drilled to meet the long holes.  Much like a second pito-static system.  The probe was mounted to a wing rib that forms the inside corner of a baggage locker.  I routed the small plastic tubeing inside the lightening holes of the ribs and up the inside of the fuselage.  There isn't any electicity involved unless you want to put a POST light on the gauge.  I'll look for pix too.

  Ron

 

 

 JAPhillipsGA(at)aol.com (JAPhillipsGA(at)aol.com) wrote:  	  Quote: 	
		  Ron, good to hear from you. I just pulled my DG, vac and all that plumbing from the plane so I have an empty hole in the dash (EHITD) I could fill with an LRI. What kind do you have and how difficult is it to install ? I remember you talking about it when we were flying, but my attention was on your 3300 so I missed some of it. I really don't want to have to take a wing off to install something. Best regards, Bill

 do not archive

DCP_0696.JPG

Description:

Filesize:

146.45 KB

Viewed:

380 Time(s)

AOA_installation_002.jpg

Description:

Filesize:

213.4 KB

Viewed:

362 Time(s)

AOA_installation_005.jpg

Description:

Filesize:

114.26 KB

Viewed:

370 Time(s)

AOA_installation_007.jpg

Description:

Filesize:

92.15 KB

Viewed:

388 Time(s)

p.mulwitz(at)worldnet.att
Guest

Posted: Tue Jun 06, 2006 7:50 am Post subject: Low speed takeoffs and stall Airpseed. LRI

Hi Gig,



I don't have a Dynon unit yet.  I may choose one, but I am also 

seriously considering a Blue Mountain unit.



I built my LRI as a time filler while I was waiting 3 months for my 

wing kit.  I am glad to learn it is a great instrument.  It also has 

the quality that it doesn't require power and is unlikely to 

fail.  That means it could be considered a backup for an EFIS except 

for the fact it doesn't really help with anything except takeoff and landing.



As a practical matter, I am planning on only VFR flight.  That means 

I don't really need any instruments at all.  I would like to get an 

instrument rating and fly my XL that way, but I can't do that until 

the FAA decides the third class medical is no longer needed.  I know 

they are considering that move, but they want to see how well using a 

driver's license as medical qualification works under the Sport Pilot rule.



I think the AOA/LRI indicator should be separate from the EFIS 

anyway.  It should be very easy to spot at the critical moments 

during takeoff and landing approach when it is most useful.  I am 

afraid the one built into the Dynon unit will be too hard to spot to 

be really useful at that point.



If it sounds like I am a little confused on this whole subject then I 

have done a really good job of writing about it.



Paul

XL wings

do not archive



At 06:41 AM 6/6/2006, you wrote:



 	  Quote: 	
		  I'm a little curious. You've got a Dynon unit right? Is there a 

reason other than redundancy that you aren't just using the AOA that 

is part of the unit?




	


----

p.mulwitz(at)worldnet.att
Guest

Posted: Tue Jun 06, 2006 10:13 am Post subject: Low speed takeoffs and stall Airpseed. LRI

 	  Quote: 	
		  The probe was mounted to a wing rib that forms the inside corner of 

a baggage locker.


	


-

I decided to mount the LRI probe and pitot/static probes on oval 

metal plates similar to the one used to access the fuel 

strainer.  That allows me to remove them while moving the wing around 

in my shop so they don't get broken off.



Paul

XL wings

JohnDRead(at)aol.com
Guest

Posted: Thu Jun 15, 2006 2:24 pm Post subject: Low speed takeoffs and stall Airpseed. LRI

safe unsubscribe

Display posts from previous:

	Matronics Email Lists Forum Index -> Zenith-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