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Europa VNE

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peterz(at)zutrasoft.com
Guest

Posted: Sat Aug 05, 2017 9:06 am Post subject: Europa VNE

I am attempting to determine the maximum usable HP that the Europa while remaining below the factory published VNE and have a few questions for the factory (if anyone with the history is listening) and existing Europa fliers:



1- The factory published VNE is:  "VNE (IAS)  [url=tel:165%20191%20307]165kn  191mph 30[/url]7kmh". Is this VNE based on a structural limit, or a flutter limit?

2- If the factory's VNE is determined by a flutter limit, I would have to assume that the 191mph is at sea-level density altitude - does anyone know if this assumption is valid? This would mean that at 13k ft, it would be reduced to ~160mph IAS and even less up heigher (I have attached a very informative article regarding VNE and TAS). Does anyone know if the factory ever executed proper flutter testing?

3- What is the max level speed obtained by Europa fliers (likely with a 914)? I am asking because I hear of 914 fliers cruising at 140ish Knots IAS at 75% (86hp?) down low, but am wondering where on the Europa's drag curve this is.  Is it near the flattening section of the exponential speed/hp curve (or conversely the escalating drag curve), or is there still some room before that "drag-wall" is reached?  What I am attempting to determine is what the speed would be for a Europa mono (with fairings etc.) with a constant speed prop, and continuous 110-120 cruise hp?  I do realize that these numbers would be very prop dependent etc.

Many thanks for any and all insight/experience,

Cheers and blue skies,

Pete

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davidjoyce(at)doctors.org
Guest

Posted: Sat Aug 05, 2017 9:38 am Post subject: Europa VNE

Pete, I cannot give you an answer to 1 & 2 but I dare say Ivan Shaw would be prepared to give you chapter and verse if you asked him, or Andy Draper at the LAA. As to 3. My 914 mono XS with speed kit did 156 TAS at 2000 ft level and 164 kt TAS at 6,500ft and exceeds VNE at any height over that. Note these are True air speeds. My smart Blue Mountain EFIS had a TAS read out. They were also done scrupulously with an observer at near max AUW, as poart of a comparison of a low twist Woodcomp SR2000 and a high twist Woodcomp SR3000W CS props, the latter giving the speed above and the low twist prop consistently 4 kts less. Certainly it is not at all difficult to exceed VNE if you are travelling at high cruise speed and dive to avoid something. We are required by the LAA to take the plane to VNE each year for our Permit renewal and 165 kts always feels as smooth as 120 assuming still air. 

Regards, David Joyce, GXSDJ 

   

 

On 2017-08-05 18:04, Pete wrote:  	  Quote: 	
		    

   

   

 I am attempting to determine the maximum usable HP that the Europa while remaining below the factory published VNE and have a few questions for the factory (if anyone with the history is listening) and existing Europa fliers:1- The factory published VNE is:  "VNE (IAS)  [url=tel:165%20191%20307]165kn  191mph 30[/url]7kmh". Is this VNE based on a structural limit, or a flutter limit?

  

 2- If the factory's VNE is determined by a flutter limit, I would have to assume that the 191mph is at sea-level density altitude - does anyone know if this assumption is valid? This would mean that at 13k ft, it would be reduced to ~160mph IAS and even less up heigher (I have attached a very informative article regarding VNE and TAS). Does anyone know if the factory ever executed proper flutter testing?

  

 3- What is the max level speed obtained by Europa fliers (likely with a 914)? I am asking because I hear of 914 fliers cruising at 140ish Knots IAS at 75% (86hp?) down low, but am wondering where on the Europa's drag curve this is.  Is it near the flattening section of the exponential speed/hp curve (or conversely the escalating drag curve), or is there still some room before that "drag-wall" is reached?  What I am attempting to determine is what the speed would be for a Europa mono (with fairings etc.) with a constant speed prop, and continuous 110-120 cruise hp?  I do realize that these numbers would be very prop dependent etc.

  

 Many thanks for any and all insight/experience,

 Cheers and blue skies,

 Pete

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gilles.thesee(at)free.fr
Guest

Posted: Sat Aug 05, 2017 11:41 am Post subject: Europa VNE

Le 05/08/2017 Ã  19:36, davidjoyce(at)doctors.org.uk a Ã©crit :

 	  Quote: 	
		  

  As to 3. My 914 mono XS with speed kit did 156 TAS at 2000 ft level 

 and 164 kt TAS at 6,500ft and exceeds VNE at any height over that. 

 Note these are True air speeds. My smart Blue Mountain EFIS had a TAS 

 read out.




	


Hi all,



I would like to point out that Vno, Vne etc. have to do with aerodynamic 

efforts and so are IAS velocities (or more accurately CAS).



David, concerning your speed reports, are those *cruise* numbers (75% 

power), or all out performance numbers ? What were your engine & prop 

settings ? Were the conditions near standard, or was the weather cold, etc.

And BTW, what were your IAS's ?



Thanks,

-- 

Best regards,

Gilles

http://contrails.free.fr

http://lapierre.skunkworks.free.fr

- The Matronics Europa-List Email Forum -

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MJKTuck(at)cs.com
Guest

Posted: Sat Aug 05, 2017 12:20 pm Post subject: Europa VNE

I've been trying to figure why you have to show the aircraft can reach VNE as part of the annual check (i.e. every year). Seems quite a needlessly 'risky' thing to do. Either it does or ... what?

Regards,

Martin Tuck

Sent from my iPhone

 	  Quote: 	
		   On Aug 5, 2017, at 2:40 PM, GTH <gilles.thesee(at)free.fr> wrote:

> Le 05/08/2017 Ã  19:36, davidjoyce(at)doctors.org.uk a Ã©crit :

> 

> As to 3. My 914 mono XS with speed kit did 156 TAS at 2000 ft level and 164 kt TAS at 6,500ft and exceeds VNE at any height over that. Note these are True air speeds. My smart Blue Mountain EFIS had a TAS read out.

> 

 Hi all,

 I would like to point out that Vno, Vne etc. have to do with aerodynamic efforts and so are IAS velocities (or more accurately CAS).

 David, concerning your speed reports, are those *cruise* numbers (75% power), or all out performance numbers ? What were your engine & prop settings ? Were the conditions near standard, or was the weather cold, etc.

 And BTW, what were your IAS's ?

 Thanks,

 -- 

 Best regards,

 Gilles

 http://contrails.free.fr

 http://lapierre.skunkworks.free.fr

- The Matronics Europa-List Email Forum -

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davidjoyce(at)doctors.org
Guest

Posted: Sat Aug 05, 2017 1:06 pm Post subject: Europa VNE

Gilles, These speeds were at 100% power (as opposed to the 115% max power available on the 914 for just 5mins). It was several years ago now and I have long since lost the paper that had those sort of other details on, but I remember it as a typical British summer day - probably around 20C. At 6500ft & up the pitch was on its coarse stop and probably I could have gone faster with a coarser  coarse setting. I will send you the report written at the time. 

Regards, David 

   

 

On 2017-08-05 20:40, GTH wrote:  	  Quote: 	
		    	  Quote: 	
		  --> Europa-List message posted by: GTH <gilles.thesee(at)free.fr (gilles.thesee(at)free.fr)>



Le 05/08/2017 à 19:36, davidjoyce(at)doctors.org.uk (davidjoyce(at)doctors.org.uk) a écrit :As to 3. My 914 mono XS with speed kit did 156 TAS at 2000 ft level and 164 kt TAS at 6,500ft and exceeds VNE at any height over that. Note these are True air speeds. My smart Blue Mountain EFIS had a TAS read out.Hi all,



I would like to point out that Vno, Vne etc. have to do with aerodynamic efforts and so are IAS velocities (or more accurately CAS).



David, concerning your speed reports, are those *cruise* numbers (75% power), or all out performance numbers ? What were your engine & prop settings ? Were the conditions near standard, or was the weather cold, etc.

And BTW, what were your IAS's ?



Thanks,

-- 

Best regards,

Gilles

http://contrails.free.fr

http://lapierre.skunkworks.free.fr

ttp://www.matronics.com/Navigator?Europa-List

ics.com

.com

.matronics.com/contribution

- The Matronics Europa-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?Europa-List

gilles.thesee(at)free.fr
Guest

Posted: Sat Aug 05, 2017 1:17 pm Post subject: Europa VNE

Le 05/08/2017 Ã            23:05, davidjoyce(at)doctors.org.uk (davidjoyce(at)doctors.org.uk) a Ã©critÂ :

         

      	  Quote: 	
		                  

Gilles, These speeds were at 100% power (as             opposed to the 115% max power available on the 914 for just             5mins). It was several years ago now and I have long since             lost the paper that had those sort of other details on, but             I remember it as a typical British summer day - probably             around 20C. At 6500ft & up the pitch was on its coarse             stop and probably I could have gone faster with a coarser             Â coarse setting. I will send you the report written at the             time.     	
     David,

     

     Thank you for the details. I'm always interested in hard numbers     .

     -- 

       Best regards,

       Gilles

       http://contrails.free.fr

       http://lapierre.skunkworks.free.fr

- The Matronics Europa-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:

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peterz(at)zutrasoft.com
Guest

Posted: Sat Aug 05, 2017 1:34 pm Post subject: Europa VNE

Me too! 

Thx,

Pete



On Aug 5, 2017, at 5:17 PM, GTH <gilles.thesee(at)free.fr (gilles.thesee(at)free.fr)> wrote:

 	  Quote: 	
		                     Le 05/08/2017 Ã            23:05, davidjoyce(at)doctors.org.uk (davidjoyce(at)doctors.org.uk) a Ã©crit :

         

      	  Quote: 	
		                  

Gilles, These speeds were at 100% power (as             opposed to the 115% max power available on the 914 for just             5mins). It was several years ago now and I have long since             lost the paper that had those sort of other details on, but             I remember it as a typical British summer day - probably             around 20C. At 6500ft & up the pitch was on its coarse             stop and probably I could have gone faster with a coarser              coarse setting. I will send you the report written at the             time.     	
     David,

     

     Thank you for the details. I'm always interested in hard numbers     .

     -- 

       Best regards,

       Gilles

       http://contrails.free.fr

       http://lapierre.skunkworks.free.fr

- The Matronics Europa-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?Europa-List

davidjoyce(at)doctors.org
Guest

Posted: Sun Aug 06, 2017 1:44 am Post subject: Europa VNE

Good question - shall ask LAA next time I see them. Ours not to reason why! David 

   

 

On 2017-08-05 21:14, Martin Tuck wrote:  	  Quote: 	
		    	  Quote: 	
		  --> Europa-List message posted by: Martin Tuck <MJKTuck(at)cs.com (MJKTuck(at)cs.com)>



I've been trying to figure why you have to show the aircraft can reach VNE as part of the annual check (i.e. every year). Seems quite a needlessly 'risky' thing to do. Either it does or ... what?



Regards,

Martin Tuck



Sent from my iPhoneOn Aug 5, 2017, at 2:40 PM, GTH <gilles.thesee(at)free.fr (gilles.thesee(at)free.fr)> wrote: --> Europa-List message posted by: GTH <gilles.thesee(at)free.fr (gilles.thesee(at)free.fr)>  	  Quote: 	
		  Le 05/08/2017 à 19:36, davidjoyce(at)doctors.org.uk (davidjoyce(at)doctors.org.uk) a écrit : As to 3. My 914 mono XS with speed kit did 156 TAS at 2000 ft level and 164 kt TAS at 6,500ft and exceeds VNE at any height over that. Note these are True air speeds. My smart Blue Mountain EFIS had a TAS read out. 	
 Hi all, I would like to point out that Vno, Vne etc. have to do with aerodynamic efforts and so are IAS velocities (or more accurately CAS). David, concerning your speed reports, are those *cruise* numbers (75% power), or all out performance numbers ? What were your engine & prop settings ? Were the conditions near standard, or was the weather cold, etc. And BTW, what were your IAS's ? Thanks, -- Best regards, Gilles http://contrails.free.fr http://lapierre.skunkworks.free.fr

ttp://www.matronics.com/Navigator?Europa-List

ics.com

.com

.matronics.com/contribution

- The Matronics Europa-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?Europa-List

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