 |
Matronics Email Lists
Web Forum Interface to the Matronics Email Lists
|
| View previous topic :: View next topic |
| Author |
Message |
jbyak52(at)gmail.com
Guest
|
 Posted: Fri Jan 10, 2014 9:23 am Post subject: Yak 52 maneuver speed |
 |
|
I’m looking for the Yak 52’s maneuver speed (Va)
[quote][b]
| | - The Matronics Yak-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?Yak-List |
|
|
|
| Back to top |
|
 |
Etienne Verhellen
Joined: 13 Apr 2007
Posts: 141
Location: Belgium
|
|
| Back to top |
|
|
jbyak52(at)gmail.com
Guest
|
| Posted: Fri Jan 10, 2014 4:38 pm Post subject: Yak 52 maneuver speed |
|
|
Thanks but I'm looking for Va, the lowest speed at which you can generate the max allowable (7) g.
Sent from my iPad
| | - The Matronics Yak-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?Yak-List |
|
|
|
| Back to top |
|
|
McFly
Joined: 21 May 2012
Posts: 101
Location: Scottsdale, AZ
|
| Posted: Fri Jan 10, 2014 6:52 pm Post subject: Yak 52 maneuver speed |
|
|
Maneuvering speed can be found mathematically. The formula is Vs (stall speed clean) multiplied by the square root of the g (7). If you put it into an excel formula it would be Vs*n where n = acceleration. You can then use this to build a Vn diagram if you so choose.
Good luck!
Todd McCutchan
Fast Aircraft
T-34A & Yak-50
Cell - 260.402.1740
Email: todd(at)fastaircraft.com
Skype: tmccutchan
Web: www.fastaircraft.com & www.toddmccutchanairshows.com
--
| | - The Matronics Yak-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?Yak-List |
|
_________________
Todd McCutchan
Fast Aircraft
T-34A - N134FA
KDVT Hangar 33-13
Cell - 260.402.1740
Email: todd@fastaircraft.com
Skype: tmccutchan
Web: www.fastaircraft.com & www.flyams.com |
|
| Back to top |
|
|
McFly
Joined: 21 May 2012
Posts: 101
Location: Scottsdale, AZ
|
| Posted: Fri Jan 10, 2014 7:05 pm Post subject: Yak 52 maneuver speed |
|
|
Please also keep in mind that stall speed (at least in USA aircraft) is calculated based on MTOW and farthest allowable aft CG. If you are flying at weights below MTOW the Va will also be lower as it decreases as weight decreases (rule of thumb is 1 knot per 100 lbs).
Again you can calculate this using the same formula if you know the lower Vs or if Vs is unknown for the reduced weight you can calculate using Vaw2w1<![endif]--><![if !msEquation]>[img]cid:image003.png(at)01CF0E3F.3EE02840[/img]<![endif]>
Va would be the maneuvering speed you previously calculated based on MTOW. W2 is the current weight and W1 is the MTOW.
Cheers!
Todd McCutchan
Fast Aircraft
T-34A & Yak-50
Cell - 260.402.1740
Email: todd(at)fastaircraft.com (todd(at)fastaircraft.com)
Skype: tmccutchan
Web: www.fastaircraft.com & www.toddmccutchanairshows.com
From: owner-yak-list-server(at)matronics.com [mailto:owner-yak-list-server(at)matronics.com] On Behalf Of Todd McCutchan
Sent: Friday, January 10, 2014 7:52 PM
To: yak-list(at)matronics.com
Subject: RE: Re: Yak 52 maneuver speed
Maneuvering speed can be found mathematically. The formula is Vs (stall speed clean) multiplied by the square root of the g (7). If you put it into an excel formula it would be Vs*n where n = acceleration. You can then use this to build a Vn diagram if you so choose.
Good luck!
Todd McCutchan
Fast Aircraft
T-34A & Yak-50
Cell - 260.402.1740
Email: todd(at)fastaircraft.com (todd(at)fastaircraft.com)
Skype: tmccutchan
Web: www.fastaircraft.com & www.toddmccutchanairshows.com
--
| | - The Matronics Yak-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?Yak-List |
|
| Description: |
|
| Filesize: |
672 Bytes |
| Viewed: |
13249 Time(s) |
|
_________________
Todd McCutchan
Fast Aircraft
T-34A - N134FA
KDVT Hangar 33-13
Cell - 260.402.1740
Email: todd@fastaircraft.com
Skype: tmccutchan
Web: www.fastaircraft.com & www.flyams.com |
|
| Back to top |
|
|
jbyak52(at)gmail.com
Guest
|
| Posted: Sat Jan 11, 2014 6:14 am Post subject: Yak 52 maneuver speed |
|
|
Thanks Todd, good information.
Jim
Sent from my iPad
On Jan 10, 2014, at 22:05, "Todd McCutchan" <todd(at)fastaircraft.com (todd(at)fastaircraft.com)> wrote:
[quote]v\:* {behavior:url(#default#VML);} o\:* {behavior:url(#default#VML);} w\:* {behavior:url(#default#VML);} .shape {behavior:url(#default#VML);} <![endif]--> <![endif]--> <![endif]-->
Please also keep in mind that stall speed (at least in USA aircraft) is calculated based on MTOW and farthest allowable aft CG. If you are flying at weights below MTOW the Va will also be lower as it decreases as weight decreases (rule of thumb is 1 knot per 100 lbs).
Again you can calculate this using the same formula if you know the lower Vs or if Vs is unknown for the reduced weight you can calculate using Vaw2w1<![endif]--><image003.png>
Va would be the maneuvering speed you previously calculated based on MTOW. W2 is the current weight and W1 is the MTOW.
Cheers!
Todd McCutchan
Fast Aircraft
T-34A & Yak-50
Cell - 260.402.1740
Email: todd(at)fastaircraft.com (todd(at)fastaircraft.com)
Skype: tmccutchan
Web: www.fastaircraft.com & www.toddmccutchanairshows.com
From: owner-yak-list-server(at)matronics.com (owner-yak-list-server(at)matronics.com) [mailto:owner-yak-list-server(at)matronics.com (owner-yak-list-server(at)matronics.com)] On Behalf Of Todd McCutchan
Sent: Friday, January 10, 2014 7:52 PM
To: yak-list(at)matronics.com (yak-list(at)matronics.com)
Subject: RE: Re: Yak 52 maneuver speed
Maneuvering speed can be found mathematically. The formula is Vs (stall speed clean) multiplied by the square root of the g (7). If you put it into an excel formula it would be Vs*√n where n = acceleration. You can then use this to build a Vn diagram if you so choose.
Good luck!
Todd McCutchan
Fast Aircraft
T-34A & Yak-50
Cell - 260.402.1740
Email: todd(at)fastaircraft.com (todd(at)fastaircraft.com)
Skype: tmccutchan
Web: www.fastaircraft.com & www.toddmccutchanairshows.com
--
| | - The Matronics Yak-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?Yak-List |
|
|
|
| Back to top |
|
|
bwade154(at)yahoo.com
Guest
|
| Posted: Sat Jan 11, 2014 6:20 am Post subject: Yak 52 maneuver speed |
|
|
Found on Mark Jefferies websiteBasic DataAirspeedsNever exceed speed VNE450 KPH
243 KtsManeuvering speed360 KPH
194 KtsGear extension speed200 KPH
108 KtsFlap extension speed170 KHP
91 KtsApproach speed150 KPH
87 KtsStall speed105 KPH
60 Kts
On Friday, January 10, 2014 10:12 PM, Todd McCutchan <todd(at)fastaircraft.com> wrote:
Please also keep in mind that stall speed (at least in USA aircraft) is calculated based on MTOW and farthest allowable aft CG. If you are flying at weights below MTOW the Va will also be lower as it decreases as weight decreases (rule of thumb is 1 knot per 100 lbs).
Again you can calculate this using the same formula if you know the lower Vs or if Vs is unknown for the reduced weight you can calculate using [img]cid:1.1755939441(at)web164904.mail.bf1.yahoo.com[/img]
Va would be the maneuvering speed you previously calculated based on MTOW. W2 is the current weight and W1 is the MTOW.
Cheers!
Todd McCutchan
Fast Aircraft
T-34A & Yak-50
Cell - 260.402.1740
Email: todd(at)fastaircraft.com (todd(at)fastaircraft.com)
Skype: tmccutchan
Web: www.fastaircraft.com & www.toddmccutchanairshows.com
From: owner-yak-list-server(at)matronics.com [mailto:owner-yak-list-server(at)matronics.com] On Behalf Of Todd McCutchan
Sent: Friday, January 10, 2014 7:52 PM
To: yak-list(at)matronics.com
Subject: RE: Re: Yak 52 maneuver speed
Maneuvering speed can be found mathematically. The formula is Vs (stall speed clean) multiplied by the square root of the g (7). If you put it into an excel formula it would be Vs*√n where n = acceleration. You can then use this to build a Vn diagram if you so choose.
Good luck!
Todd McCutchan
Fast Aircraft
T-34A & Yak-50
Cell - 260.402.1740
Email: todd(at)fastaircraft.com (todd(at)fastaircraft.com)
Skype: tmccutchan
Web: http://www.fastaircraft.com/ & http://www.toddmccutchanairshows.com/
--
| | - The Matronics Yak-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?Yak-List |
|
| Description: |
|
| Filesize: |
672 Bytes |
| Viewed: |
13239 Time(s) |
|
|
|
| Back to top |
|
|
McFly
Joined: 21 May 2012
Posts: 101
Location: Scottsdale, AZ
|
| Posted: Sat Jan 11, 2014 7:34 am Post subject: Yak 52 maneuver speed |
|
|
194 knots for Va seems crazy high for plane with a 60 knot stall speed. I am wondering if something is lost in translation?
Todd McCutchanT-34A & Yak-50
Cell: (260) 402-1740
E-mail: todd(at)fastaircraft.com (todd(at)fastaircraft.com)
www.fastaircraft.com
On Jan 11, 2014, at 5:19 PM, bill wade <bwade154(at)yahoo.com (bwade154(at)yahoo.com)> wrote:
[quote]Found on Mark Jefferies websiteBasic DataAirspeedsNever exceed speed VNE450 KPH
243 KtsManeuvering speed360 KPH
194 KtsGear extension speed200 KPH
108 KtsFlap extension speed170 KHP
91 KtsApproach speed150 KPH
87 KtsStall speed105 KPH
60 Kts
On Friday, January 10, 2014 10:12 PM, Todd McCutchan <todd(at)fastaircraft.com (todd(at)fastaircraft.com)> wrote:
Please also keep in mind that stall speed (at least in USA aircraft) is calculated based on MTOW and farthest allowable aft CG. If you are flying at weights below MTOW the Va will also be lower as it decreases as weight decreases (rule of thumb is 1 knot per 100 lbs).
Again you can calculate this using the same formula if you know the lower Vs or if Vs is unknown for the reduced weight you can calculate using <image003.png>
Va would be the maneuvering speed you previously calculated based on MTOW. W2 is the current weight and W1 is the MTOW.
Cheers!
Todd McCutchan
Fast Aircraft
T-34A & Yak-50
Cell - 260.402.1740
Email: todd(at)fastaircraft.com (todd(at)fastaircraft.com)
Skype: tmccutchan
Web: www.fastaircraft.com & www.toddmccutchanairshows.com
From: owner-yak-list-server(at)matronics.com (owner-yak-list-server(at)matronics.com) [mailto:owner-yak-list-server(at)matronics.com (owner-yak-list-server(at)matronics.com)] On Behalf Of Todd McCutchan
Sent: Friday, January 10, 2014 7:52 PM
To: yak-list(at)matronics.com (yak-list(at)matronics.com)
Subject: RE: Re: Yak 52 maneuver speed
Maneuvering speed can be found mathematically. The formula is Vs (stall speed clean) multiplied by the square root of the g (7). If you put it into an excel formula it would be Vs*√n where n = acceleration. You can then use this to build a Vn diagram if you so choose.
Good luck!
Todd McCutchan
Fast Aircraft
T-34A & Yak-50
Cell - 260.402.1740
Email: todd(at)fastaircraft.com (todd(at)fastaircraft.com)
Skype: tmccutchan
Web: http://www.fastaircraft.com/ & http://www.toddmccutchanairshows.com/
--
| | - The Matronics Yak-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?Yak-List |
|
_________________
Todd McCutchan
Fast Aircraft
T-34A - N134FA
KDVT Hangar 33-13
Cell - 260.402.1740
Email: todd@fastaircraft.com
Skype: tmccutchan
Web: www.fastaircraft.com & www.flyams.com |
|
| Back to top |
|
|
hess737(at)aol.com
Guest
|
| Posted: Sat Jan 11, 2014 7:47 am Post subject: Yak 52 maneuver speed |
|
|
Todd
If I remember correctly, maximum maneuver speed is a lot like our military corner velocity. At that speed you can just pull max G at stall angle of attack. One knot above that and you over G. One knot below and you stall before reaching max G. 194 makes sense as 7 Gs is a lot and needs a head of steam to achieve. Hope this helps.
Richard HessC 404-964-4885
On Jan 11, 2014, at 10:33, Todd McCutchan <todd(at)fastaircraft.com (todd(at)fastaircraft.com)> wrote:
[quote]194 knots for Va seems crazy high for plane with a 60 knot stall speed. I am wondering if something is lost in translation?
Todd McCutchanT-34A & Yak-50
Cell: (260) 402-1740
E-mail: todd(at)fastaircraft.com (todd(at)fastaircraft.com)
www.fastaircraft.com
On Jan 11, 2014, at 5:19 PM, bill wade <bwade154(at)yahoo.com (bwade154(at)yahoo.com)> wrote:
[quote]Found on Mark Jefferies websiteBasic DataAirspeedsNever exceed speed VNE450 KPH
243 KtsManeuvering speed360 KPH
194 KtsGear extension speed200 KPH
108 KtsFlap extension speed170 KHP
91 KtsApproach speed150 KPH
87 KtsStall speed105 KPH
60 Kts
On Friday, January 10, 2014 10:12 PM, Todd McCutchan <todd(at)fastaircraft.com (todd(at)fastaircraft.com)> wrote:
Please also keep in mind that stall speed (at least in USA aircraft) is calculated based on MTOW and farthest allowable aft CG. If you are flying at weights below MTOW the Va will also be lower as it decreases as weight decreases (rule of thumb is 1 knot per 100 lbs).
Again you can calculate this using the same formula if you know the lower Vs or if Vs is unknown for the reduced weight you can calculate using <image003.png>
Va would be the maneuvering speed you previously calculated based on MTOW. W2 is the current weight and W1 is the MTOW.
Cheers!
Todd McCutchan
Fast Aircraft
T-34A & Yak-50
Cell - 260.402.1740
Email: todd(at)fastaircraft.com (todd(at)fastaircraft.com)
Skype: tmccutchan
Web: www.fastaircraft.com & www.toddmccutchanairshows.com
From: owner-yak-list-server(at)matronics.com (owner-yak-list-server(at)matronics.com) [mailto:owner-yak-list-server(at)matronics.com (owner-yak-list-server(at)matronics.com)] On Behalf Of Todd McCutchan
Sent: Friday, January 10, 2014 7:52 PM
To: yak-list(at)matronics.com (yak-list(at)matronics.com)
Subject: RE: Re: Yak 52 maneuver speed
Maneuvering speed can be found mathematically. The formula is Vs (stall speed clean) multiplied by the square root of the g (7). If you put it into an excel formula it would be Vs*√n where n = acceleration. You can then use this to build a Vn diagram if you so choose.
Good luck!
Todd McCutchan
Fast Aircraft
T-34A & Yak-50
Cell - 260.402.1740
Email: todd(at)fastaircraft.com (todd(at)fastaircraft.com)
Skype: tmccutchan
Web: http://www.fastaircraft.com/ & http://www.toddmccutchanairshows.com/
--
| | - The Matronics Yak-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?Yak-List |
|
|
|
| Back to top |
|
|
McFly
Joined: 21 May 2012
Posts: 101
Location: Scottsdale, AZ
|
| Posted: Sat Jan 11, 2014 8:18 am Post subject: Yak 52 maneuver speed |
|
|
Va and cornering speed are indeed exactly the same.
However the math on this one does not pan out.
60 (Vs) x square root of 7 (max g) = 158.7 knots which is believable.
For Va to be 194 stall speed (Vs) would have to be substantially higher or the max g would have to be higher.
Something is clearly being lost here but I don't know what.
Todd McCutchanT-34A & Yak-50
Cell: (260) 402-1740
E-mail: todd(at)fastaircraft.com (todd(at)fastaircraft.com)
www.fastaircraft.com
On Jan 11, 2014, at 6:47 PM, Richard Hess <hess737(at)aol.com (hess737(at)aol.com)> wrote:
[quote]Todd
If I remember correctly, maximum maneuver speed is a lot like our military corner velocity. At that speed you can just pull max G at stall angle of attack. One knot above that and you over G. One knot below and you stall before reaching max G. 194 makes sense as 7 Gs is a lot and needs a head of steam to achieve. Hope this helps.
Richard HessC 404-964-4885
On Jan 11, 2014, at 10:33, Todd McCutchan <todd(at)fastaircraft.com (todd(at)fastaircraft.com)> wrote:
[quote]194 knots for Va seems crazy high for plane with a 60 knot stall speed. I am wondering if something is lost in translation?
Todd McCutchanT-34A & Yak-50
Cell: (260) 402-1740
E-mail: todd(at)fastaircraft.com (todd(at)fastaircraft.com)
www.fastaircraft.com
On Jan 11, 2014, at 5:19 PM, bill wade <bwade154(at)yahoo.com (bwade154(at)yahoo.com)> wrote:
[quote]Found on Mark Jefferies websiteBasic DataAirspeedsNever exceed speed VNE450 KPH
243 KtsManeuvering speed360 KPH
194 KtsGear extension speed200 KPH
108 KtsFlap extension speed170 KHP
91 KtsApproach speed150 KPH
87 KtsStall speed105 KPH
60 Kts
On Friday, January 10, 2014 10:12 PM, Todd McCutchan <todd(at)fastaircraft.com (todd(at)fastaircraft.com)> wrote:
Please also keep in mind that stall speed (at least in USA aircraft) is calculated based on MTOW and farthest allowable aft CG. If you are flying at weights below MTOW the Va will also be lower as it decreases as weight decreases (rule of thumb is 1 knot per 100 lbs).
Again you can calculate this using the same formula if you know the lower Vs or if Vs is unknown for the reduced weight you can calculate using <image003.png>
Va would be the maneuvering speed you previously calculated based on MTOW. W2 is the current weight and W1 is the MTOW.
Cheers!
Todd McCutchan
Fast Aircraft
T-34A & Yak-50
Cell - 260.402.1740
Email: todd(at)fastaircraft.com (todd(at)fastaircraft.com)
Skype: tmccutchan
Web: www.fastaircraft.com & www.toddmccutchanairshows.com
From: owner-yak-list-server(at)matronics.com (owner-yak-list-server(at)matronics.com) [mailto:owner-yak-list-server(at)matronics.com (owner-yak-list-server(at)matronics.com)] On Behalf Of Todd McCutchan
Sent: Friday, January 10, 2014 7:52 PM
To: yak-list(at)matronics.com (yak-list(at)matronics.com)
Subject: RE: Re: Yak 52 maneuver speed
Maneuvering speed can be found mathematically. The formula is Vs (stall speed clean) multiplied by the square root of the g (7). If you put it into an excel formula it would be Vs*√n where n = acceleration. You can then use this to build a Vn diagram if you so choose.
Good luck!
Todd McCutchan
Fast Aircraft
T-34A & Yak-50
Cell - 260.402.1740
Email: todd(at)fastaircraft.com (todd(at)fastaircraft.com)
Skype: tmccutchan
Web: http://www.fastaircraft.com/ & http://www.toddmccutchanairshows.com/
--
| | - The Matronics Yak-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?Yak-List |
|
_________________
Todd McCutchan
Fast Aircraft
T-34A - N134FA
KDVT Hangar 33-13
Cell - 260.402.1740
Email: todd@fastaircraft.com
Skype: tmccutchan
Web: www.fastaircraft.com & www.flyams.com |
|
| Back to top |
|
|
McFly
Joined: 21 May 2012
Posts: 101
Location: Scottsdale, AZ
|
| Posted: Sat Jan 11, 2014 8:26 am Post subject: Yak 52 maneuver speed |
|
|
If 194 knots were actually used as maneuvering speed a maximum elevator deflection would generate 10.45 g's; clearly in excess of 7 g structural limit. This is a believable ultimate structural failure load though (generally structural failure is 150% of certified g; at least in Western aircraft).
Again, something is not translating correctly.
Todd McCutchanT-34A & Yak-50
Cell: (260) 402-1740
E-mail: todd(at)fastaircraft.com (todd(at)fastaircraft.com)
www.fastaircraft.com
On Jan 11, 2014, at 6:47 PM, Richard Hess <hess737(at)aol.com (hess737(at)aol.com)> wrote:
[quote]Todd
If I remember correctly, maximum maneuver speed is a lot like our military corner velocity. At that speed you can just pull max G at stall angle of attack. One knot above that and you over G. One knot below and you stall before reaching max G. 194 makes sense as 7 Gs is a lot and needs a head of steam to achieve. Hope this helps.
Richard HessC 404-964-4885
On Jan 11, 2014, at 10:33, Todd McCutchan <todd(at)fastaircraft.com (todd(at)fastaircraft.com)> wrote:
[quote]194 knots for Va seems crazy high for plane with a 60 knot stall speed. I am wondering if something is lost in translation?
Todd McCutchanT-34A & Yak-50
Cell: (260) 402-1740
E-mail: todd(at)fastaircraft.com (todd(at)fastaircraft.com)
www.fastaircraft.com
On Jan 11, 2014, at 5:19 PM, bill wade <bwade154(at)yahoo.com (bwade154(at)yahoo.com)> wrote:
[quote]Found on Mark Jefferies websiteBasic DataAirspeedsNever exceed speed VNE450 KPH
243 KtsManeuvering speed360 KPH
194 KtsGear extension speed200 KPH
108 KtsFlap extension speed170 KHP
91 KtsApproach speed150 KPH
87 KtsStall speed105 KPH
60 Kts
On Friday, January 10, 2014 10:12 PM, Todd McCutchan <todd(at)fastaircraft.com (todd(at)fastaircraft.com)> wrote:
Please also keep in mind that stall speed (at least in USA aircraft) is calculated based on MTOW and farthest allowable aft CG. If you are flying at weights below MTOW the Va will also be lower as it decreases as weight decreases (rule of thumb is 1 knot per 100 lbs).
Again you can calculate this using the same formula if you know the lower Vs or if Vs is unknown for the reduced weight you can calculate using <image003.png>
Va would be the maneuvering speed you previously calculated based on MTOW. W2 is the current weight and W1 is the MTOW.
Cheers!
Todd McCutchan
Fast Aircraft
T-34A & Yak-50
Cell - 260.402.1740
Email: todd(at)fastaircraft.com (todd(at)fastaircraft.com)
Skype: tmccutchan
Web: www.fastaircraft.com & www.toddmccutchanairshows.com
From: owner-yak-list-server(at)matronics.com (owner-yak-list-server(at)matronics.com) [mailto:owner-yak-list-server(at)matronics.com (owner-yak-list-server(at)matronics.com)] On Behalf Of Todd McCutchan
Sent: Friday, January 10, 2014 7:52 PM
To: yak-list(at)matronics.com (yak-list(at)matronics.com)
Subject: RE: Re: Yak 52 maneuver speed
Maneuvering speed can be found mathematically. The formula is Vs (stall speed clean) multiplied by the square root of the g (7). If you put it into an excel formula it would be Vs*√n where n = acceleration. You can then use this to build a Vn diagram if you so choose.
Good luck!
Todd McCutchan
Fast Aircraft
T-34A & Yak-50
Cell - 260.402.1740
Email: todd(at)fastaircraft.com (todd(at)fastaircraft.com)
Skype: tmccutchan
Web: http://www.fastaircraft.com/ & http://www.toddmccutchanairshows.com/
--
| | - The Matronics Yak-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?Yak-List |
|
_________________
Todd McCutchan
Fast Aircraft
T-34A - N134FA
KDVT Hangar 33-13
Cell - 260.402.1740
Email: todd@fastaircraft.com
Skype: tmccutchan
Web: www.fastaircraft.com & www.flyams.com |
|
| Back to top |
|
|
hess737(at)aol.com
Guest
|
|
| Back to top |
|
|
McFly
Joined: 21 May 2012
Posts: 101
Location: Scottsdale, AZ
|
| Posted: Sat Jan 11, 2014 8:37 am Post subject: Yak 52 maneuver speed |
|
|
It actually has nothing to do with aircraft design (at this stage) and Va has nothing to do with sustained g, it is instantaneous g caused by rapid and full deflection of a control surface.
Just like a B-52 and an F-16 both have the exact same turn radius at 400 knots if both are pulling 4 g's the math for finding Va and turn radius, etc is just that. Math.
As I previously posted burying the stick at 157 knots will yield 7 g's with a 60 knot Vs and doing so at 194 KIAS will give you 10.45.
I would strongly discourage anyone from using 194 as Va.
Of course I have been wrong before...
Todd McCutchanT-34A & Yak-50
Cell: (260) 402-1740
E-mail: todd(at)fastaircraft.com (todd(at)fastaircraft.com)
www.fastaircraft.com
On Jan 11, 2014, at 7:27 PM, Richard Hess <hess737(at)aol.com (hess737(at)aol.com)> wrote:
[quote]Me neither. It could be that the particular wing and fuselage bleeds so much energy that a higher speed is necessary to initially achieve the max G. Regardless, if you're pulling more than 4-5 Gs during classic aerobatics you're doing something wrong... 
Richard Hess
President
International Jets, Inc.
Cell 404-964-4885
--
| | - The Matronics Yak-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?Yak-List |
|
_________________
Todd McCutchan
Fast Aircraft
T-34A - N134FA
KDVT Hangar 33-13
Cell - 260.402.1740
Email: todd@fastaircraft.com
Skype: tmccutchan
Web: www.fastaircraft.com & www.flyams.com |
|
| Back to top |
|
|
jbyak52(at)gmail.com
Guest
|
| Posted: Sat Jan 11, 2014 5:40 pm Post subject: Yak 52 maneuver speed |
|
|
Good discussion. Anyone who plans to flys their airplane near max performance needs to have a good understanding of the available g's in all flight regimes. Corner speed is probably the most critical since it gives you the speed for max g's. Below it and you are limited in low altitude pull outs and other situations which could be critical.
Sent from my iPad
On Jan 10, 2014, at 22:05, "Todd McCutchan" <todd(at)fastaircraft.com (todd(at)fastaircraft.com)> wrote:
[quote]v\:* {behavior:url(#default#VML);} o\:* {behavior:url(#default#VML);} w\:* {behavior:url(#default#VML);} .shape {behavior:url(#default#VML);} <![endif]--> <![endif]--> <![endif]-->
Please also keep in mind that stall speed (at least in USA aircraft) is calculated based on MTOW and farthest allowable aft CG. If you are flying at weights below MTOW the Va will also be lower as it decreases as weight decreases (rule of thumb is 1 knot per 100 lbs).
Again you can calculate this using the same formula if you know the lower Vs or if Vs is unknown for the reduced weight you can calculate using Vaw2w1<![endif]--><image003.png>
Va would be the maneuvering speed you previously calculated based on MTOW. W2 is the current weight and W1 is the MTOW.
Cheers!
Todd McCutchan
Fast Aircraft
T-34A & Yak-50
Cell - 260.402.1740
Email: todd(at)fastaircraft.com (todd(at)fastaircraft.com)
Skype: tmccutchan
Web: www.fastaircraft.com & www.toddmccutchanairshows.com
From: owner-yak-list-server(at)matronics.com (owner-yak-list-server(at)matronics.com) [mailto:owner-yak-list-server(at)matronics.com (owner-yak-list-server(at)matronics.com)] On Behalf Of Todd McCutchan
Sent: Friday, January 10, 2014 7:52 PM
To: yak-list(at)matronics.com (yak-list(at)matronics.com)
Subject: RE: Re: Yak 52 maneuver speed
Maneuvering speed can be found mathematically. The formula is Vs (stall speed clean) multiplied by the square root of the g (7). If you put it into an excel formula it would be Vs*√n where n = acceleration. You can then use this to build a Vn diagram if you so choose.
Good luck!
Todd McCutchan
Fast Aircraft
T-34A & Yak-50
Cell - 260.402.1740
Email: todd(at)fastaircraft.com (todd(at)fastaircraft.com)
Skype: tmccutchan
Web: www.fastaircraft.com & www.toddmccutchanairshows.com
--
| | - The Matronics Yak-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?Yak-List |
|
|
|
| Back to top |
|
|
mike_beresford(at)yahoo.c
Guest
|
| Posted: Sat Jan 11, 2014 10:55 pm Post subject: Yak 52 maneuver speed |
|
|
Hi all
Manoeuvre speed is a defined speed in the design of the aircraft, if using standards such as FAR 23 / CS23. The Russian definition may well differ. Va is a single speed, and does not vary with aircraft weight or CG.
Although the speed is usually defined in terms of the formula Vs*√n, this represents the minimum Va. It may be higher than that, if the designer elects to designate a higher number. (See FAR 23.335(c)). This may well be the case of an aerobatic aircraft?
The speed that most pilots would describe as "manoeuvre speed" is now defined as "operating moneuvering speed", Vo. (See FAR 23.1507).
To quote the FAA Advisory Circular (23-19):
48. What is the design maneuvering speed VA?
a. The design maneuvering speed is a value chosen by the applicant. It may not
be less than Vs√ n and need not be greater than Vc, but it could be greater if the applicant
chose the higher value. The loads resulting from full control surface deflections at VA are
used to design the empennage and ailerons in part 23, §§ 23.423, 23.441, and 23.455.
b. VA should not be interpreted as a speed that would permit the pilot
unrestricted flight-control movement without exceeding airplane structural limits, nor
should it be interpreted as a gust penetration speed. Only if VA = Vs √n will the airplane
stall in a nose-up pitching maneuver at, or near, limit load factor. For airplanes where
VA>VS√n, the pilot would have to check the maneuver; otherwise the airplane would
exceed the limit load factor.
c. Amendment 23-45 added the operating maneuvering speed, VO, in § 23.1507.
VO is established not greater than VS√n, and it is a speed where the airplane will stall in a
nose-up pitching maneuver before exceeding the airplane structural limits.
Hopefully this doesn't complicate things too much.
Blue skies
Mike Beresford
On Sunday, 12 January 2014, 12:47, Jim Burke <jbyak52(at)gmail.com> wrote:
Good discussion. Anyone who plans to flys their airplane near max performance needs to have a good understanding of the available g's in all flight regimes. Corner speed is probably the most critical since it gives you the speed for max g's. Below it and you are limited in low altitude pull outs and other situations which could be critical.
Sent from my iPad
On Jan 10, 2014, at 22:05, "Todd McCutchan" <todd(at)fastaircraft.com (todd(at)fastaircraft.com)> wrote:
[quote]Please also keep in mind that stall speed (at least in USA aircraft) is calculated based on MTOW and farthest allowable aft CG. If you are flying at weights below MTOW the Va will also be lower as it decreases as weight decreases (rule of thumb is 1 knot per 100 lbs).
Again you can calculate this using the same formula if you know the lower Vs or if Vs is unknown for the reduced weight you can calculate using <image003.png>
Va would be the maneuvering speed you previously calculated based on MTOW. W2 is the current weight and W1 is the MTOW.
Cheers!
Todd McCutchan
Fast Aircraft
T-34A & Yak-50
Cell - 260.402.1740
Email: todd(at)fastaircraft.com (todd(at)fastaircraft.com)
Skype: tmccutchan
Web: www.fastaircraft.com & www.toddmccutchanairshows.com
From: owner-yak-list-server(at)matronics.com (owner-yak-list-server(at)matronics.com) [mailto:owner-yak-list-server(at)matronics.com (owner-yak-list-server(at)matronics.com)] On Behalf Of Todd McCutchan
Sent: Friday, January 10, 2014 7:52 PM
To: yak-list(at)matronics.com (yak-list(at)matronics.com)
Subject: RE: Re: Yak 52 maneuver speed
Maneuvering speed can be found mathematically. The formula is Vs (stall speed clean) multiplied by the square root of the g (7). If you put it into an excel formula it would be Vs*√n where n = acceleration. You can then use this to build a Vn diagram if you so choose.
Good luck!
Todd McCutchan
Fast Aircraft
T-34A & Yak-50
Cell - 260.402.1740
Email: todd(at)fastaircraft.com (todd(at)fastaircraft.com)
Skype: tmccutchan
Web: http://www.fastaircraft.com/ & http://www.toddmccutchanairshows.com/
--
| | - The Matronics Yak-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?Yak-List |
|
|
|
| Back to top |
|
|
McFly
Joined: 21 May 2012
Posts: 101
Location: Scottsdale, AZ
|
| Posted: Sun Jan 12, 2014 2:49 am Post subject: Yak 52 maneuver speed |
|
|
Very interesting info Mike. Thanks for sharing.
As usual here is info also from the FAA in the form of a SAIB which directly contradicts what they also say in FAR 23 which you have posted.
http://www.eaa.org/news/2011/ce-11-17.pdf
And straight from Far 23
http://www.ecfr.gov/cgi-bin/retrieveECFR?gp=&SID=cc49468715c3314f42170e150777c736&n=14y1.0.1.3.10&r=PART&ty=HTML#14:1.0.1.3.10.3.70.9
(c) Design maneuvering speed VA. For VA, the following applies:
(1) VA may not be less than VS√n where—
(i) VS is a computed stalling speed with flaps retracted at the design weight, normally based on the maximum airplane normal force coefficients, CNA; and
(ii) n is the limit maneuvering load factor used in design
(2) The value of VA need not exceed the value of VC used in design.
And
23.425 and 23.441 are specific to Va as defined above which as you stated apply to horizontal and vertical tail surfaces.
AOPA gets in the mix here: http://flighttraining.aopa.org/magazine/2012/July/feature-velocity.html
And the PHAK (Pilots Handbook of Aeronautical Knowledge) by the FAA it is defines as "the maximum speed at which an aircraft may be stalled safely."
And then defines it again as "(Va) - the maximum speed at which the structural designs limit load can be imposed (either by gusts or full deflection of the control surfaces) without causing structural damage. It is important to consider weight when referencing this speed."
And again; "Va - the calibrated design maneuvering airspeed. This is the maximum speed at which the limit load can be imposed (either by gusts or full deflection of the control surfaces) without causing structural damage. Operating at or below maneuvering speed does not provide structural protection against multiple full control inputs in more than one axis at the same time."
In the Airplane Flying Handbook (AFH) by the FAA it is defined as "Va - the design maneuvering speed. This is the "rough air" speed and the maximum speed for abrupt maneuvers. If during flight, rough air or severe turbulence is encountered, reduce the airspeed to maneuvering speed or less to minimize stress on the airplane structure. It is important to consider weight when referencing this speed."
The US government, keeping the mud clear since the Air Commerce Act of 1926.
Of course all of this is moot as we are discussing an uncertified Russian airplane. Yakovlev is really the only place I would trust to define just what they meant and why the speeds are what they are.
I personally will stick to Vs x square root 7 for Va on the Yak 50/52. So assuming 57 KIAS Vs for a 52, Va = 150.8 KIAS.
As Richard Hess also already stated, if you are pulling more than 4 - 5 g's you are doing it wrong.
Todd McCutchanT-34A & Yak-50
Cell: (260) 402-1740
E-mail: todd(at)fastaircraft.com (todd(at)fastaircraft.com)
www.fastaircraft.com
On Jan 12, 2014, at 9:54 AM, Mike Beresford <mike_beresford(at)yahoo.co.uk (mike_beresford(at)yahoo.co.uk)> wrote:
[quote]Hi all
Manoeuvre speed is a defined speed in the design of the aircraft, if using standards such as FAR 23 / CS23. The Russian definition may well differ. Va is a single speed, and does not vary with aircraft weight or CG.
Although the speed is usually defined in terms of the formula Vs*√n, this represents the minimum Va. It may be higher than that, if the designer elects to designate a higher number. (See FAR 23.335(c)). This may well be the case of an aerobatic aircraft?
The speed that most pilots would describe as "manoeuvre speed" is now defined as "operating moneuvering speed", Vo. (See FAR 23.1507).
To quote the FAA Advisory Circular (23-19):
48. What is the design maneuvering speed VA?
a. The design maneuvering speed is a value chosen by the applicant. It may not
be less than Vs√ n and need not be greater than Vc, but it could be greater if the applicant
chose the higher value. The loads resulting from full control surface deflections at VA are
used to design the empennage and ailerons in part 23, §§ 23.423, 23.441, and 23.455.
b. VA should not be interpreted as a speed that would permit the pilot
unrestricted flight-control movement without exceeding airplane structural limits, nor
should it be interpreted as a gust penetration speed. Only if VA = Vs √n will the airplane
stall in a nose-up pitching maneuver at, or near, limit load factor. For airplanes where
VA>VS√n, the pilot would have to check the maneuver; otherwise the airplane would
exceed the limit load factor.
c. Amendment 23-45 added the operating maneuvering speed, VO, in § 23.1507.
VO is established not greater than VS√n, and it is a speed where the airplane will stall in a
nose-up pitching maneuver before exceeding the airplane structural limits.
Hopefully this doesn't complicate things too much.
Blue skies
Mike Beresford
On Sunday, 12 January 2014, 12:47, Jim Burke <jbyak52(at)gmail.com (jbyak52(at)gmail.com)> wrote:
Good discussion. Anyone who plans to flys their airplane near max performance needs to have a good understanding of the available g's in all flight regimes. Corner speed is probably the most critical since it gives you the speed for max g's. Below it and you are limited in low altitude pull outs and other situations which could be critical.
Sent from my iPad
On Jan 10, 2014, at 22:05, "Todd McCutchan" <todd(at)fastaircraft.com (todd(at)fastaircraft.com)> wrote:
[quote]Please also keep in mind that stall speed (at least in USA aircraft) is calculated based on MTOW and farthest allowable aft CG. If you are flying at weights below MTOW the Va will also be lower as it decreases as weight decreases (rule of thumb is 1 knot per 100 lbs).
Again you can calculate this using the same formula if you know the lower Vs or if Vs is unknown for the reduced weight you can calculate using <image003.png>
Va would be the maneuvering speed you previously calculated based on MTOW. W2 is the current weight and W1 is the MTOW.
Cheers!
Todd McCutchan
Fast Aircraft
T-34A & Yak-50
Cell - 260.402.1740
Email: todd(at)fastaircraft.com (todd(at)fastaircraft.com)
Skype: tmccutchan
Web: www.fastaircraft.com & www.toddmccutchanairshows.com
From: owner-yak-list-server(at)matronics.com (owner-yak-list-server(at)matronics.com) [mailto:owner-yak-list-server(at)matronics.com (owner-yak-list-server(at)matronics.com)] On Behalf Of Todd McCutchan
Sent: Friday, January 10, 2014 7:52 PM
To: yak-list(at)matronics.com (yak-list(at)matronics.com)
Subject: RE: Re: Yak 52 maneuver speed
Maneuvering speed can be found mathematically. The formula is Vs (stall speed clean) multiplied by the square root of the g (7). If you put it into an excel formula it would be Vs*√n where n = acceleration. You can then use this to build a Vn diagram if you so choose.
Good luck!
Todd McCutchan
Fast Aircraft
T-34A & Yak-50
Cell - 260.402.1740
Email: todd(at)fastaircraft.com (todd(at)fastaircraft.com)
Skype: tmccutchan
Web: http://www.fastaircraft.com/ & http://www.toddmccutchanairshows.com/
--
| | - The Matronics Yak-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?Yak-List |
|
_________________
Todd McCutchan
Fast Aircraft
T-34A - N134FA
KDVT Hangar 33-13
Cell - 260.402.1740
Email: todd@fastaircraft.com
Skype: tmccutchan
Web: www.fastaircraft.com & www.flyams.com |
|
| Back to top |
|
|
mike_beresford(at)yahoo.c
Guest
|
| Posted: Sun Jan 12, 2014 3:29 am Post subject: Yak 52 maneuver speed |
|
|
Which does help muddy the water even more 
My understanding is that the confusion starts because the manoeuvre speed defined in the design loads requirements (23.335) was not the same manoeuvre speed required in the operating limitations section (23.1507). See the notice of rule making, [url=http://rgl.faa.gov/Regulatory_and_Guidance_Library/rgNPRM.nsf/2ed8a85bb3dd48e68525644900598dfb/646bfd6587baf0ad852569230061a774!OpenDocument]http://rgl.faa.gov/Regulatory_and_Guidance_Library/rgNPRM.nsf/2ed8a85bb3dd48e68525644900598dfb/646bfd6587baf0ad852569230061a774!OpenDocument[/url]
I'd guess that the SAIB is specifically aimed at aircraft with Va instead of Vo (?)
Does anyone know how the Russians define Va?
Regards
Mike
On Sunday, 12 January 2014, 21:48, Todd McCutchan <todd(at)fastaircraft.com> wrote:
Very interesting info Mike. Thanks for sharing.
As usual here is info also from the FAA in the form of a SAIB which directly contradicts what they also say in FAR 23 which you have posted.
http://www.eaa.org/news/2011/ce-11-17.pdf
And straight from Far 23
http://www.ecfr.gov/cgi-bin/retrieveECFR?gp=&SID=cc49468715c3314f42170e150777c736&n=14y1.0.1.3.10&r=PART&ty=HTML#14:1.0.1.3.10.3.70.9
(c) Design maneuvering speed VA. For VA, the following applies:
(1) VA may not be less than VS√n where—
(i) VS is a computed stalling speed with flaps retracted at the design weight, normally based on the maximum airplane normal force coefficients, CNA; and
(ii)n is the limit maneuvering load factor used in design
(2) The value of VA need not exceed the value of VC used in design.
And
23.425 and 23.441 are specific to Va as defined above which as you stated apply to horizontal and vertical tail surfaces.
AOPA gets in the mix here: http://flighttraining.aopa.org/magazine/2012/July/feature-velocity.html
And the PHAK (Pilots Handbook of Aeronautical Knowledge) by the FAA it is defines as "the maximum speed at which an aircraft may be stalled safely."
And then defines it again as "(Va) - the maximum speed at which the structural designs limit load can be imposed (either by gusts or full deflection of the control surfaces) without causing structural damage. It is important to consider weight when referencing this speed."
And again; "Va - the calibrated design maneuvering airspeed. This is the maximum speed at which the limit load can be imposed (either by gusts or full deflection of the control surfaces) without causing structural damage. Operating at or below maneuvering speed does not provide structural protection against multiple full control inputs in more than one axis at the same time."
In the Airplane Flying Handbook (AFH) by the FAA it is defined as "Va - the design maneuvering speed. This is the "rough air" speed and the maximum speed for abrupt maneuvers. If during flight, rough air or severe turbulence is encountered, reduce the airspeed to maneuvering speed or less to minimize stress on the airplane structure. It is important to consider weight when referencing this speed."
The US government, keeping the mud clear since the Air Commerce Act of 1926.
Of course all of this is moot as we are discussing an uncertified Russian airplane. Yakovlev is really the only place I would trust to define just what they meant and why the speeds are what they are.
I personally will stick to Vs x square root 7 for Va on the Yak 50/52. So assuming 57 KIAS Vs for a 52, Va = 150.8 KIAS.
As Richard Hess also already stated, if you are pulling more than 4 - 5 g's you are doing it wrong.
Todd McCutchanT-34A & Yak-50
Cell: (260) 402-1740
E-mail: todd(at)fastaircraft.com (todd(at)fastaircraft.com)
http://www.fastaircraft.com/
On Jan 12, 2014, at 9:54 AM, Mike Beresford <mike_beresford(at)yahoo.co.uk (mike_beresford(at)yahoo.co.uk)> wrote:
[quote]Hi all
Manoeuvre speed is a defined speed in the design of the aircraft, if using standards such as FAR 23 / CS23. The Russian definition may well differ. Va is a single speed, and does not vary with aircraft weight or CG.
Although the speed is usually defined in terms of the formula Vs*√n, this represents the minimum Va. It may be higher than that, if the designer elects to designate a higher number. (See FAR 23.335(c)). This may well be the case of an aerobatic aircraft?
The speed that most pilots would describe as "manoeuvre speed" is now defined as "operating moneuvering speed", Vo. (See FAR 23.1507).
To quote the FAA Advisory Circular (23-19):
48. What is the design maneuvering speed VA?
a. The design maneuvering speed is a value chosen by the applicant. It may not
be less than Vs√ n and need not be greater than Vc, but it could be greater if the applicant
chose the higher value. The loads resulting from full control surface deflections at VA are
used to design the empennage and ailerons in part 23, §§ 23.423, 23.441, and 23.455.
b. VA should not be interpreted as a speed that would permit the pilot
unrestricted flight-control movement without exceeding airplane structural limits, nor
should it be interpreted as a gust penetration speed. Only if VA = Vs √n will the airplane
stall in a nose-up pitching maneuver at, or near, limit load factor. For airplanes where
VA>VS√n, the pilot would have to check the maneuver; otherwise the airplane would
exceed the limit load factor.
c. Amendment 23-45 added the operating maneuvering speed, VO, in § 23.1507.
VO is established not greater than VS√n, and it is a speed where the airplane will stall in a
nose-up pitching maneuver before exceeding the airplane structural limits.
Hopefully this doesn't complicate things too much.
Blue skies
Mike Beresford
On Sunday, 12 January 2014, 12:47, Jim Burke <jbyak52(at)gmail.com (jbyak52(at)gmail.com)> wrote:
Good discussion. Anyone who plans to flys their airplane near max performance needs to have a good understanding of the available g's in all flight regimes. Corner speed is probably the most critical since it gives you the speed for max g's. Below it and you are limited in low altitude pull outs and other situations which could be critical.
Sent from my iPad
On Jan 10, 2014, at 22:05, "Todd McCutchan" <todd(at)fastaircraft.com (todd(at)fastaircraft.com)> wrote:
[quote]Please also keep in mind that stall speed (at least in USA aircraft) is calculated based on MTOW and farthest allowable aft CG. If you are flying at weights below MTOW the Va will also be lower as it decreases as weight decreases (rule of thumb is 1 knot per 100 lbs).
Again you can calculate this using the same formula if you know the lower Vs or if Vs is unknown for the reduced weight you can calculate using <image003.png>
Va would be the maneuvering speed you previously calculated based on MTOW. W2 is the current weight and W1 is the MTOW.
Cheers!
Todd McCutchan
Fast Aircraft
T-34A & Yak-50
Cell - 260.402.1740
Email: todd(at)fastaircraft.com (todd(at)fastaircraft.com)
Skype: tmccutchan
Web: www.fastaircraft.com & www.toddmccutchanairshows.com
From: owner-yak-list-server(at)matronics.com (owner-yak-list-server(at)matronics.com) [mailto:owner-yak-list-server(at)matronics.com (owner-yak-list-server(at)matronics.com)] On Behalf Of Todd McCutchan
Sent: Friday, January 10, 2014 7:52 PM
To: yak-list(at)matronics.com (yak-list(at)matronics.com)
Subject: RE: Re: Yak 52 maneuver speed
Maneuvering speed can be found mathematically. The formula is Vs (stall speed clean) multiplied by the square root of the g (7). If you put it into an excel formula it would be Vs*√n where n = acceleration. You can then use this to build a Vn diagram if you so choose.
Good luck!
Todd McCutchan
Fast Aircraft
T-34A & Yak-50
Cell - 260.402.1740
Email: todd(at)fastaircraft.com (todd(at)fastaircraft.com)
Skype: tmccutchan
Web: http://www.fastaircraft.com/ & http://www.toddmccutchanairshows.com/
--
| | - The Matronics Yak-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?Yak-List |
|
|
|
| Back to top |
|
|
McFly
Joined: 21 May 2012
Posts: 101
Location: Scottsdale, AZ
|
| Posted: Sun Jan 12, 2014 4:16 am Post subject: Yak 52 maneuver speed |
|
|
That NPRM is from 1985 and appears to have been superseded.
The current FAR 23.335c does not allow for an arbitrary Va speed above Vs x sqrt (n)
Part 23 AIRWORTHINESS STANDARDS: NORMAL, UTILITY, ACROBATIC, AND COMMUTER CATEGORY AIRPLANES
Subpart G--Operating Limitations and Information
Sec. 23.1507
[Operating] maneuvering speed.
[The maximum operating maneuvering speed, VO, must be established as an operating limitation. VO is a selected speed that is not greater than established in Sec. 23.335(c).]
Kind regards,
Todd McCutchan
T-34A & Yak-50
Cell: (260) 402-1740
E-mail: todd(at)fastaircraft.com
www.fastaircraft.com
[quote] On Jan 12, 2014, at 2:28 PM, Mike Beresford <mike_beresford(at)yahoo.co.uk> wrote:
Which does help muddy the water even more
My understanding is that the confusion starts because the manoeuvre speed defined in the design loads requirements (23.335) was not the same manoeuvre speed required in the operating limitations section (23.1507). See the notice of rule making, http://rgl.faa.gov/Regulatory_and_Guidance_Library/rgNPRM.nsf/2ed8a85bb3dd48e68525644900598dfb/646bfd6587baf0ad852569230061a774!OpenDocument
I'd guess that the SAIB is specifically aimed at aircraft with Va instead of Vo (?)
Does anyone know how the Russians define Va?
Regards
Mike
On Sunday, 12 January 2014, 21:48, Todd McCutchan <todd(at)fastaircraft.com> wrote:
Very interesting info Mike. Thanks for sharing.
As usual here is info also from the FAA in the form of a SAIB which directly contradicts what they also say in FAR 23 which you have posted.
http://www.eaa.org/news/2011/ce-11-17.pdf
And straight from Far 23
http://www.ecfr.gov/cgi-bin/retrieveECFR?gp=&SID=cc49468715c3314f42170e150777c736&n=14y1.0.1.3.10&r=PART&ty=HTML#14:1.0.1.3.10.3.70.9
(c) Design maneuvering speed VA. For VA, the following applies:
(1) VA may not be less than VS√n where—
(i) VS is a computed stalling speed with flaps retracted at the design weight, normally based on the maximum airplane normal force coefficients, CNA; and
(ii) n is the limit maneuvering load factor used in design
(2) The value of VA need not exceed the value of VC used in design.
And
23.425 and 23.441 are specific to Va as defined above which as you stated apply to horizontal and vertical tail surfaces.
AOPA gets in the mix here: http://flighttraining.aopa.org/magazine/2012/July/feature-velocity.html
And the PHAK (Pilots Handbook of Aeronautical Knowledge) by the FAA it is defines as "the maximum speed at which an aircraft may be stalled safely."
And then defines it again as "(Va) - the maximum speed at which the structural designs limit load can be imposed (either by gusts or full deflection of the control surfaces) without causing structural damage. It is important to consider weight when referencing this speed."
And again; "Va - the calibrated design maneuvering airspeed. This is the maximum speed at which the limit load can be imposed (either by gusts or full deflection of the control surfaces) without causing structural damage. Operating at or below maneuvering speed does not provide structural protection against multiple full control inputs in more than one axis at the same time."
In the Airplane Flying Handbook (AFH) by the FAA it is defined as "Va - the design maneuvering speed. This is the "rough air" speed and the maximum speed for abrupt maneuvers. If during flight, rough air or severe turbulence is encountered, reduce the airspeed to maneuvering speed or less to minimize stress on the airplane structure. It is important to consider weight when referencing this speed."
The US government, keeping the mud clear since the Air Commerce Act of 1926.
Of course all of this is moot as we are discussing an uncertified Russian airplane. Yakovlev is really the only place I would trust to define just what they meant and why the speeds are what they are.
I personally will stick to Vs x square root 7 for Va on the Yak 50/52. So assuming 57 KIAS Vs for a 52, Va = 150.8 KIAS.
As Richard Hess also already stated, if you are pulling more than 4 - 5 g's you are doing it wrong.
Todd McCutchan
T-34A & Yak-50
Cell: (260) 402-1740
E-mail: todd(at)fastaircraft.com
http://www.fastaircraft.com/
> On Jan 12, 2014, at 9:54 AM, Mike Beresford <mike_beresford(at)yahoo.co.uk> wrote:
>
> Hi all
>
> Manoeuvre speed is a defined speed in the design of the aircraft, if using standards such as FAR 23 / CS23. The Russian definition may well differ. Va is a single speed, and does not vary with aircraft weight or CG.
>
> Although the speed is usually defined in terms of the formula Vs*√n, this represents the minimum Va. It may be higher than that, if the designer elects to designate a higher number. (See FAR 23.335(c)). This may well be the case of an aerobatic aircraft?
>
> The speed that most pilots would describe as "manoeuvre speed" is now defined as "operating moneuvering speed", Vo. (See FAR 23.1507).
>
> To quote the FAA Advisory Circular (23-19):
> 48. What is the design maneuvering speed VA?
> a. The design maneuvering speed is a value chosen by the applicant. It may not
> be less than Vs√ n and need not be greater than Vc, but it could be greater if the applicant
> chose the higher value. The loads resulting from full control surface deflections at VA are
> used to design the empennage and ailerons in part 23, §§ 23.423, 23.441, and 23.455.
>
> b. VA should not be interpreted as a speed that would permit the pilot
> unrestricted flight-control movement without exceeding airplane structural limits, nor
> should it be interpreted as a gust penetration speed. Only if VA = Vs √n will the airplane
> stall in a nose-up pitching maneuver at, or near, limit load factor. For airplanes where
> VA>VS√n, the pilot would have to check the maneuver; otherwise the airplane would
> exceed the limit load factor.
>
> c. Amendment 23-45 added the operating maneuvering speed, VO, in § 23.1507.
> VO is established not greater than VS√n, and it is a speed where the airplane will stall in a
> nose-up pitching maneuver before exceeding the airplane structural limits
| | - The Matronics Yak-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?Yak-List |
|
_________________
Todd McCutchan
Fast Aircraft
T-34A - N134FA
KDVT Hangar 33-13
Cell - 260.402.1740
Email: todd@fastaircraft.com
Skype: tmccutchan
Web: www.fastaircraft.com & www.flyams.com |
|
| Back to top |
|
|
McFly
Joined: 21 May 2012
Posts: 101
Location: Scottsdale, AZ
|
| Posted: Sun Jan 12, 2014 8:48 am Post subject: Yak 52 maneuver speed |
|
|
Hi Mike,
It has been a day of interesting reading (for me anyway). I am now completely confused and believe that you are after all correct though I can’t seem to prove you are correct in the current FAR Part 23.335c as it does not seem to allow for an arbitrary maneuvering speed above Vs√n though it appears it previously may have. I just can’t find it anywhere in current documents.
So my current understanding is (under FAR Part 23):
Vo
“Operating Speed” is equal to or less than Vs√n. Aircraft will stall prior to reaching g limit (not sure if this provides negative g protection or not). Did not exist prior to 1993. New certified aircraft must placard this. Changes with weight.
VA
“Design Maneuvering Speed” is equal to or greater than Vs√n but is not required to be greater than Vc No structural protection is provided for the airframe, only the flight control surface? Certified aircraft will define this in the POH. May or may not change with weight?
VNO
“Max Structural Cruising Speed” and is no less than the minimum value of Vc allowed under 23.335, and not more than the lesser of Vc or .89 of Vne. Additionally it is the speed at which the aircraft can encounter sharp edged gusts of up to 25 fps (prior to 1963) now 50 fps (below 20,000’ MSL) and not exceed the aircraft structural limits (+/-). An interesting side note is that 747 wake turb vortices are around 300 fps. Hmm…
VNE
“Never Exceed Speed” and is not less than .9 VD and not more than the lesser of .9 VD or .9 of the maximum speed shown under FAR 23.251. Additionally it is the speed at which the aircraft can encounter sharp edged gusts of up to 15 fps (prior to 1963) and now 25 fps (below 20,000’ MSL) and not exceed the aircraft structural limits (+/-).
Outside of FAR Part 23 “Maneuvering Speed” seems to depend on the actual aircraft being spoken about as it seems to be up to the aircraft manufacturer; which is bizarre.
I will continue to base my personal “VA“ on Vs√n which also is a “g available” indicator and “corner velocity” at max positive g. It is the best I can do with what I know / have available to me.
I have no idea on what requirements/guidelines the Russians used in design of their aircraft (Yak 50 designed in 1972 / Yak 52 designed in 1973)
I wish we had some Russian aeronautical engineers from Yak who could provide some insight to some of these crazy numbers I have seen for the 50 and 52.
Thanks again for the great discussion and education!
Todd McCutchan
Fast Aircraft
T-34A & Yak-50
Cell - 260.402.1740
Email: todd(at)fastaircraft.com (todd(at)fastaircraft.com)
Skype: tmccutchan
Web: www.fastaircraft.com & www.toddmccutchanairshows.com
From: owner-yak-list-server(at)matronics.com [mailto:owner-yak-list-server(at)matronics.com] On Behalf Of Todd McCutchan
Sent: Sunday, January 12, 2014 5:16 AM
To: yak-list(at)matronics.com
Subject: Re: Re: Yak 52 maneuver speed
That NPRM is from 1985 and appears to have been superseded.
The current FAR 23.335c does not allow for an arbitrary Va speed above Vs x sqrt (n)
Part 23 AIRWORTHINESS STANDARDS: NORMAL, UTILITY, ACROBATIC, AND COMMUTER CATEGORY AIRPLANES
Subpart G--Operating Limitations and Information
Sec. 23.1507
[Operating] maneuvering speed.
[The maximum operating maneuvering speed, VO, must be established as an operating limitation. VO is a selected speed that is not greater than [img]http://rgl.faa.gov/Regulatory_and_Guidance_Library/rgFAR.nsf/0/2a0aa756267efe8f85256687007232cc/SectionRule/0.390!OpenElement&FieldElemFormat=gif[/img] established in Sec. 23.335(c).]
Kind regards,
Todd McCutchan
T-34A & Yak-50
Cell: (260) 402-1740
E-mail: todd(at)fastaircraft.com (todd(at)fastaircraft.com)
www.fastaircraft.com
On Jan 12, 2014, at 2:28 PM, Mike Beresford <mike_beresford(at)yahoo.co.uk (mike_beresford(at)yahoo.co.uk)> wrote:
[quote]
Which does help muddy the water even more
My understanding is that the confusion starts because the manoeuvre speed defined in the design loads requirements (23.335) was not the same manoeuvre speed required in the operating limitations section (23.1507). See the notice of rule making, [url=http://rgl.faa.gov/Regulatory_and_Guidance_Library/rgNPRM.nsf/2ed8a85bb3dd48e68525644900598dfb/646bfd6587baf0ad852569230061a774!OpenDocument]http://rgl.faa.gov/Regulatory_and_Guidance_Library/rgNPRM.nsf/2ed8a85bb3dd48e68525644900598dfb/646bfd6587baf0ad852569230061a774!OpenDocument[/url]
I'd guess that the SAIB is specifically aimed at aircraft with Va instead of Vo (?)
Does anyone know how the Russians define Va?
Regards
Mike
On Sunday, 12 January 2014, 21:48, Todd McCutchan <todd(at)fastaircraft.com (todd(at)fastaircraft.com)> wrote:
Very interesting info Mike. Thanks for sharing.
As usual here is info also from the FAA in the form of a SAIB which directly contradicts what they also say in FAR 23 which you have posted.
http://www.eaa.org/news/2011/ce-11-17.pdf
And straight from Far 23
http://www.ecfr.gov/cgi-bin/retrieveECFR?gp=&SID=cc49468715c3314f42170e150777c736&n=14y1.0.1.3.10&r=PART&ty=HTML#14:1.0.1.3.10.3.70.9
(c) Design maneuvering speed VA. For VA, the following applies:
(1) VA may not be less than VS√n where—
(i) VS is a computed stalling speed with flaps retracted at the design weight, normally based on the maximum airplane normal force coefficients, CNA; and
(ii) n is the limit maneuvering load factor used in design
(2) The value of VA need not exceed the value of VC used in design.
And
23.425 and 23.441 are specific to Va as defined above which as you stated apply to horizontal and vertical tail surfaces.
AOPA gets in the mix here: http://flighttraining.aopa.org/magazine/2012/July/feature-velocity.html
And the PHAK (Pilots Handbook of Aeronautical Knowledge) by the FAA it is defines as "the maximum speed at which an aircraft may be stalled safely."
And then defines it again as "(Va) - the maximum speed at which the structural designs limit load can be imposed (either by gusts or full deflection of the control surfaces) without causing structural damage. It is important to consider weight when referencing this speed."
And again; "Va - the calibrated design maneuvering airspeed. This is the maximum speed at which the limit load can be imposed (either by gusts or full deflection of the control surfaces) without causing structural damage. Operating at or below maneuvering speed does not provide structural protection against multiple full control inputs in more than one axis at the same time."
In the Airplane Flying Handbook (AFH) by the FAA it is defined as "Va - the design maneuvering speed. This is the "rough air" speed and the maximum speed for abrupt maneuvers. If during flight, rough air or severe turbulence is encountered, reduce the airspeed to maneuvering speed or less to minimize stress on the airplane structure. It is important to consider weight when referencing this speed."
The US government, keeping the mud clear since the Air Commerce Act of 1926.
Of course all of this is moot as we are discussing an uncertified Russian airplane. Yakovlev is really the only place I would trust to define just what they meant and why the speeds are what they are.
I personally will stick to Vs x square root 7 for Va on the Yak 50/52. So assuming 57 KIAS Vs for a 52, Va = 150.8 KIAS.
As Richard Hess also already stated, if you are pulling more than 4 - 5 g's you are doing it wrong.
Todd McCutchan
T-34A & Yak-50
Cell: (260) 402-1740
E-mail: todd(at)fastaircraft.com (todd(at)fastaircraft.com)
http://www.fastaircraft.com/
On Jan 12, 2014, at 9:54 AM, Mike Beresford <mike_beresford(at)yahoo.co.uk (mike_beresford(at)yahoo.co.uk)> wrote:
[quote]
Hi all
Manoeuvre speed is a defined speed in the design of the aircraft, if using standards such as FAR 23 / CS23. The Russian definition may well differ. Va is a single speed, and does not vary with aircraft weight or CG.
Although the speed is usually defined in terms of the formula Vs*√n, this represents the minimum Va. It may be higher than that, if the designer elects to designate a higher number. (See FAR 23.335(c)). This may well be the case of an aerobatic aircraft?
The speed that most pilots would describe as "manoeuvre speed" is now defined as "operating moneuvering speed", Vo. (See FAR 23.1507).
To quote the FAA Advisory Circular (23-19):
48. What is the design maneuvering speed VA?
a. The design maneuvering speed is a value chosen by the applicant. It may not
be less than Vs√ n and need not be greater than Vc, but it could be greater if the applicant
chose the higher value. The loads resulting from full control surface deflections at VA are
used to design the empennage and ailerons in part 23, §§ 23.423, 23.441, and 23.455.
b. VA should not be interpreted as a speed that would permit the pilot
unrestricted flight-control movement without exceeding airplane structural limits, nor
should it be interpreted as a gust penetration speed. Only if VA = Vs √n will the airplane
stall in a nose-up pitching maneuver at, or near, limit load factor. For airplanes where
VA>VS√n, the pilot would have to check the maneuver; otherwise the airplane would
exceed the limit load factor.
c. Amendment 23-45 added the operating maneuvering speed, VO, in § 23.1507.
VO is established not greater than VS√n, and it is a speed where the airplane will stall in a
nose-up pitching maneuver before exceeding the airplane structural limits.
Hopefully this doesn't complicate things too much.
Blue skies
Mike Beresford
On Sunday, 12 January 2014, 12:47, Jim Burke <jbyak52(at)gmail.com (jbyak52(at)gmail.com)> wrote:
Good discussion. Anyone who plans to flys their airplane near max performance needs to have a good understanding of the available g's in all flight regimes. Corner speed is probably the most critical since it gives you the speed for max g's. Below it and you are limited in low altitude pull outs and other situations which could be critical.
Sent from my iPad
On Jan 10, 2014, at 22:05, "Todd McCutchan" <todd(at)fastaircraft.com (todd(at)fastaircraft.com)> wrote:
[quote]
Please also keep in mind that stall speed (at least in USA aircraft) is calculated based on MTOW and farthest allowable aft CG. If you are flying at weights below MTOW the Va will also be lower as it decreases as weight decreases (rule of thumb is 1 knot per 100 lbs).
Again you can calculate this using the same formula if you know the lower Vs or if Vs is unknown for the reduced weight you can calculate using <image003.png>
Va would be the maneuvering speed you previously calculated based on MTOW. W2 is the current weight and W1 is the MTOW.
Cheers!
Todd McCutchan
Fast Aircraft
T-34A & Yak-50
Cell - 260.402.1740
Email: todd(at)fastaircraft.com (todd(at)fastaircraft.com)
Skype: tmccutchan
Web: www.fastaircraft.com & www.toddmccutchanairshows.com
From: owner-yak-list-server(at)matronics.com (owner-yak-list-server(at)matronics.com) [mailto:owner-yak-list-server(at)matronics.com (owner-yak-list-server(at)matronics.com)] On Behalf Of Todd McCutchan
Sent: Friday, January 10, 2014 7:52 PM
To: yak-list(at)matronics.com (yak-list(at)matronics.com)
Subject: RE: Re: Yak 52 maneuver speed
Maneuvering speed can be found mathematically. The formula is Vs (stall speed clean) multiplied by the square root of the g (7). If you put it into an excel formula it would be Vs*√n where n = acceleration. You can then use this to build a Vn diagram if you so choose.
Good luck!
Todd McCutchan
Fast Aircraft
T-34A & Yak-50
Cell - 260.402.1740
Email: todd(at)fastaircraft.com (todd(at)fastaircraft.com)
Skype: tmccutchan
Web: http://www.fastaircraft.com/ & http://www.toddmccutchanairshows.com/
--
| | - The Matronics Yak-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?Yak-List |
|
_________________
Todd McCutchan
Fast Aircraft
T-34A - N134FA
KDVT Hangar 33-13
Cell - 260.402.1740
Email: todd@fastaircraft.com
Skype: tmccutchan
Web: www.fastaircraft.com & www.flyams.com |
|
| Back to top |
|
|
PaulW
Joined: 14 May 2013
Posts: 25
|
| Posted: Sun Jan 12, 2014 10:22 am Post subject: Re: Yak 52 maneuver speed |
|
|
HI
Will this attached extract from Page 64 of the YAK-52 POH help?
| | - The Matronics Yak-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?Yak-List |
|
| Description: |
|
| Filesize: |
69.69 KB |
| Viewed: |
13194 Time(s) |
|
|
|
| Back to top |
|
|
|
|
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
|
Powered by phpBB © 2001, 2005 phpBB Group
|
Get Email Distribution Too!
FAQ
Search
Memberlist
Usergroups
Register
Profile
Log in to check your private messages
Log in
