Matronics Email Lists :: View topic

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

GT Propellors

Matronics Email Lists Forum Index -> Yak-List

View previous topic :: View next topic

Author Message

richard.goode(at)russiana
Guest

Posted: Wed Jan 19, 2011 1:40 am Post subject: GT Propellors

From everything I have heard I suspect that the GT  blades do give a good advantage over the V-530 blades.But then the V-530 is a  50+ year old design,so a new blade really SHOULD perform a lot  better!

 But when is someone going to produce proper  scientific performance figures comparing these different props,including  MT,rather than saying that"acceleration is much better",or similar subjective  assesments??

 Richard Goode Aerobatics 

Rhodds Farm  

Lyonshall 

Hereford 

HR5 3LW 

United Kingdom 

  

 Tel:   +44 (0) 1544 340120 

Fax:   +44 (0) 1544 340129 

www.russianaeros.com

I’m currently in  Sri Lanka but this Mail is working,and my local phone is +94 779 132  160.

  

  

   [quote][b]

ssssskippy

Joined: 02 May 2010
Posts: 58

Posted: Wed Jan 19, 2011 2:45 am Post subject: GT Propellors

I found something not so good about the GT Prop: http://gtpropellers.com/



[/url]Of course a problem is always a possibility but the AAIB's conclusions are very bad:

 [url=http://www.aaib.gov.uk/publications/bulletins/september_2009/speedtwin_st2__g_stdl.cfm]http://www.aaib.gov.uk/publications/bulletins/september_2009/speedtwin_st2__g_stdl.cfm

[/url]Olivier

 

2011/1/19 Richard.Goode <richard.goode(at)russianaeros.com (richard.goode(at)russianaeros.com)>

[quote]        From everything I have heard I suspect that the GT  blades do give a good advantage over the V-530 blades.But then the V-530 is a  50+ year old design,so a new blade really SHOULD perform a lot  better!

 But when is someone going to produce proper  scientific performance figures comparing these different props,including  MT,rather than saying that"acceleration is much better",or similar subjective  assesments??

 Richard Goode Aerobatics 

Rhodds Farm  

Lyonshall 

Hereford 

HR5 3LW 

United Kingdom 

  

 Tel:   +44 (0) 1544 340120 

Fax:   +44 (0) 1544 340129 

[url=http://www.russianaeros.com]www.russianaeros.com

I’m currently in  Sri Lanka but this Mail is working,and my local phone is +94 779 132  160.

  

  

    	  Quote: 	
		  



et="_blank">http://www.matronics.com/Navigator?Yak-List

tp://forums.matronics.com

_blank">http://www.matronics.com/contribution



	


[b]

radiopicture

Joined: 23 Jun 2008
Posts: 263

Posted: Wed Jan 19, 2011 2:57 am Post subject: GT Propellors

That isn't this model of GT propeller, and I have never known GT to be anything less than responsive. This is not some company that just popped up overnight, and they make propellers for a pretty large range of aircraft including historic warbirds like Spitfires. As you know, anything can be put on the internet.

On Jan 19, 2011, at 5:42 AM, Olivier Vigneron wrote:

[quote]I found something not so good about the GT Prop: http://gtpropellers.com/



[/url]Of course a problem is always a possibility but the AAIB's conclusions are very bad:

 [url=http://www.aaib.gov.uk/publications/bulletins/september_2009/speedtwin_st2__g_stdl.cfm]http://www.aaib.gov.uk/publications/bulletins/september_2009/speedtwin_st2__g_stdl.cfm

[/url]Olivier

 

2011/1/19 Richard.Goode <richard.goode(at)russianaeros.com (richard.goode(at)russianaeros.com)>

 	  Quote: 	
		          From everything I have heard I suspect that the GT  blades do give a good advantage over the V-530 blades.But then the V-530 is a  50+ year old design,so a new blade really SHOULD perform a lot  better!

 But when is someone going to produce proper  scientific performance figures comparing these different props,including  MT,rather than saying that"acceleration is much better",or similar subjective  assesments??

 Richard Goode Aerobatics 

Rhodds Farm  

Lyonshall 

Hereford 

HR5 3LW 

United Kingdom 

  

 Tel:   +44 (0) 1544 340120 

Fax:   +44 (0) 1544 340129 

[url=http://www.russianaeros.com/]www.russianaeros.com

I’m currently in  Sri Lanka but this Mail is working,and my local phone is +94 779 132  160.

  

  

    	  Quote: 	
		  



et="_blank">http://www.matronics.com/Navigator?Yak-List

tp://forums.matronics.com

_blank">http://www.matronics.com/contribution



	






href="http://www.matronics.com/Navigator?Yak-List">http://www.matronics.com/Navigator?Yak-List

href="http://forums.matronics.com/">http://forums.matronics.com

href="http://www.matronics.com/contribution">http://www.matronics.com/contribution



	
[b]

radiopicture

Joined: 23 Jun 2008
Posts: 263

Posted: Wed Jan 19, 2011 2:58 am Post subject: GT Propellors

Richard:



I did find this data from Rick Volker, which I realize is anecdotal, but I think still useful and coming from someone who knows what he's doing:

 	  Quote: 	
		  Max level speed: mtv3=gt= v530=330kph

Mtv9 slower by 10 kph 

Max cruise: mtv3=gt=v530=305kph

Mtv9 slower by 8 kph 

Full power stall speed: V530=65 mph,mtv3=60 kph 

Gt=50kph , MTV 9= < 50 kph(hovering possible)-below measurable airspeed

Vertical penetration from 6G pull,330kph:

V530=1600', mtv3=1700', GT=1700',Mtv9=2000'

Time on vertical line: v530=17 second. Mtv3=20 second. GT=20 seconds.MTV 9= >30 second (hovering).

Time to climb 1000' to 2000': v530=20 second.

GT= 20 second., mtv3=17 second, mtv9=17 seconds.

Level acceleration full power, 200kph to 300kph:

V530= 17sec. GT= 17sec. Mtv3=15 sec.mtv9=16 second. 

Descent rate at idle with prop at 100%rpm:

Mtv9 =15 sec/1000',GT=32sec/1000',v530=35sec/1000',mtv3= 40sec/1000'

Note: the MTV 9 has longer blades and was optimized for static thrust. It stays much flatter power off, is significantly slower in speed, but will hover this weight aircraft. 

The GT has more static thrust than the MTV3 and more thrust from 0 to 120kph. It loses to the mtv3 at 170kph Vy climb and at 200-300kph acceleration, but has same top speed and cruise speed. The GT power off descent rate is high, suggesting the blades stay very flat at power off . 

The GT was only static balanced and was much lower vibration than the v530 which had been dynamic balanced. The MTV3 and MTV9 had been dynamic balanced and were by far the smoothest props. It would be conceivable that the GT would be smoother if dynamic balanced. The GT may need a spinner with backing plate to allow dynamic balancing to the same level as a three blade prop.  GT is developing a carbon fiber spinner that is 46 cm wide for the V530 hub. 

Vertical penetration and time on vertical line upwards were equal with mtv3 vs GT. 

From these tests, the GT is as good as the mtv3-250 three blade prop during aerobatics and may be as good an all around prop for aerobatics, travel, and short field take offs. The mtv9-260-29 has been optimized for aerobatics and air shows at the expense of slower cruise, max speed, and poor glide characteristics. It would be advisable to test the GT against the MTV9-250 with both the-27 and -29 blades.

The GT is superior to the v530 in static thrust, vertical penetration, power on stall, and vibration. It is equal in climb, midspeed acceration,cruise,and top speed. The GT has a slightly worse power off glide than the v530.  There is also more propeller braking with the GT than with the V530 on roll out after landing.

	


On Jan 19, 2011, at 4:43 AM, Richard.Goode wrote:

 	  Quote: 	
		  From everything I have heard I suspect that the GT blades do give a good advantage over the V-530 blades.But then the V-530 is a 50+ year old design,so a new blade really SHOULD perform a lot better!

But when is someone going to produce proper scientific performance figures comparing these different props,including MT,rather than saying that"acceleration is much better",or similar subjective assesments??

Richard Goode Aerobatics 

Rhodds Farm 

Lyonshall 

Hereford 

HR5 3LW 

United Kingdom

 

Tel:   +44 (0) 1544 340120 

Fax:  +44 (0) 1544 340129 

www.russianaeros.com

I’m currently in Sri Lanka but this Mail is working,and my local phone is +94 779 132 160.

 

 

 	  Quote: 	
		  



href="http://www.matronics.com/Navigator?Yak-List">http://www.matronics.com/Navigator?Yak-List

href="http://forums.matronics.com">http://forums.matronics.com

href="http://www.matronics.com/contribution">http://www.matronics.com/contribution



	


	


 [quote][b]

viperdoc(at)mindspring.co
Guest

Posted: Wed Jan 19, 2011 7:09 am Post subject: GT Propellors

You know for the majority of us that are using our YAKs and CJs for weekend attitude adjustment the superiority

Of which blade beats the other by 3 seconds is academic. Blades separating at the hub, serviceability,static vs 

Dynamic balance out of the box and overall safety of the blades are of great interest. Expense of replacement

In this down turned economy is of greater interest. For those that need to replace blades, cost,reliability, and serviceability are big issues. How much damage to the M-14 do these new composite carbon fiber blades do to the M-14 when landed gear up at idle throttle? The reliable v530 turns to saw dust without generally destroying the engine necessitating an expensive engine replacement. Any data out there on that? 

We YAK and CJ'ers are a cheap bunch you know?

?^))

doc



Sent from my iPad



On Jan 19, 2011, at 4:56 AM, Eric Wobschall <eric(at)buffaloskyline.com (eric(at)buffaloskyline.com)> wrote:



[quote]Richard:



I did find this data from Rick Volker, which I realize is anecdotal, but I think still useful and coming from someone who knows what he's doing:

 	  Quote: 	
		  Max level speed: mtv3=gt= v530=330kph

Mtv9 slower by 10 kph 

Max cruise: mtv3=gt=v530=305kph

Mtv9 slower by 8 kph lia 

Full power stall speed: V530=65 mph,mtv3=60 kph 

Gt=50kph , MTV 9= < 50 kph(hovering possible)-below measurable airspeed

Vertical penetration from 6G pull,330kph:

V530=1600', mtv3=1700', GT=1700',Mtv9=2000'

Time on vertical line: v530=17 second. Mtv3=20 second. GT=20 seconds.MTV 9= >30 second (hovering).

Time to climb 1000' to 2000': v530=20 second.

GT= 20 second., mtv3=17 second, mtv9=17 seconds.

Level acceleration full power, 200kph to 300kph:

V530= 17sec. GT= 17sec. Mtv3=15 sec.mtv9=16 second. 

Descent rate at idle with prop at 100%rpm:

Mtv9 =15 sec/1000',GT=32sec/1000',v530=35sec/1000',mtv3= 40sec/1000'

Note: the MTV 9 has longer blades and was optimized for static thrust. It stays much flatter power off, is significantly slower in speed, but will hover this weight aircraft. 

The GT has more static thrust than the MTV3 and more thrust from 0 to 120kph. It loses to the mtv3 at 170kph Vy climb and at 200-300kph acceleration, but has same top speed and cruise speed. The GT power off descent rate is high, suggesting the blades stay very flat at power off . 

The GT was only static balanced and was much lower vibration than the v530 which had been dynamic balanced. The MTV3 and MTV9 had been dynamic balanced and were by far the smoothest props. It would be conceivable that the GT would be smoother if dynamic balanced. The GT may need a spinner with backing plate to allow dynamic balancing to the same level as a three blade prop.  GT is developing a carbon fiber spinner that is 46 cm wide for the V530 hub. 

Vertical penetration and time on vertical line upwards were equal with mtv3 vs GT. 

From these tests, the GT is as good as the mtv3-250 three blade prop during aerobatics and may be as good an all around prop for aerobatics, travel, and short field take offs. The mtv9-260-29 has been optimized for aerobatics and air shows at the expense of slower cruise, max speed, and poor glide characteristics. It would be advisable to test the GT against the MTV9-250 with both the-27 and -29 blades.

The GT is superior to the v530 in static thrust, vertical penetration, power on stall, and vibration. It is equal in climb, midspeed acceration,cruise,and top speed. The GT has a slightly worse power off glide than the v530.  There is also more propeller braking with the GT than with the V530 on roll out after landing.

	


On Jan 19, 2011, at 4:43 AM, Richard.Goode wrote:

 	  Quote: 	
		  From everything I have heard I suspect that the GT blades do give a good advantage over the V-530 blades.But then the V-530 is a 50+ year old design,so a new blade really SHOULD perform a lot better!

But when is someone going to produce proper scientific performance figures comparing these different props,including MT,rather than saying that"acceleration is much better",or similar subjective assesments??

Richard Goode Aerobatics 

Rhodds Farm 

Lyonshall 

Hereford 

HR5 3LW 

United Kingdom

 

Tel:   +44 (0) 1544 340120 

Fax:  +44 (0) 1544 340129 

www.russianaeros.com

Iâ€™m currently in Sri Lanka but this Mail is working,and my local phone is +94 779 132 160.

 

 

 	  Quote: 	
		  



href="http://www.matronics.com/Navigator?Yak-List">http://www.matronics.com/Navigator?Yak-List

href="http://forums.matronics.com">http://forums.matronics.com

href="http://www.matronics.com/contribution">http://www.matronics.com/contribution



	






===================================

ef="http://www.matronics.com/Navigator?Yak-List">http://www.matronics.com/Navigator?Yak-List

===================================

ums.matronics.com">http://forums.matronics.com

===================================

http://www.matronics.com/contribution">http://www.matronics.com/contribution

===================================



	


[b]

dsavarese0812(at)bellsout
Guest

Posted: Wed Jan 19, 2011 7:38 am Post subject: GT Propellors

Now THAT's clearly one of the most intelligent comments on the subject 

of prop blades I've heard.  Thanks Doc for bringing me and probably some 

other folks on the list back down to earth.

Dennis



A. Dennis Savarese

334-285-6263

334-546-8182 (cell)

Skype: Yakguy1

www.yak-52.com



On 1/19/2011 9:06 AM, Roger Kemp M.D. wrote:

 	  Quote: 	
		   You know for the majority of us that are using our YAKs and CJs for

 weekend attitude adjustment the superiority

 Of which blade beats the other by 3 seconds is academic. Blades

 separating at the hub, serviceability,static vs

 Dynamic balance out of the box and overall safety of the blades are of

 great interest. Expense of replacement

 In this down turned economy is of greater interest. For those that need

 to replace blades, cost,reliability, and serviceability are big issues.

 How much damage to the M-14 do these new composite carbon fiber blades

 do to the M-14 when landed gear up at idle throttle? The reliable v530

 turns to saw dust without generally destroying the engine necessitating

 an expensive engine replacement. Any data out there on that?

 We YAK and CJ'ers are a cheap bunch you know?

 ?^))

 doc



 Sent from my iPad



 On Jan 19, 2011, at 4:56 AM, Eric Wobschall <eric(at)buffaloskyline.com

 <mailto:eric(at)buffaloskyline.com>> wrote:



> Richard:

>

> I did find this data from Rick Volker, which I realize is anecdotal,

> but I think still useful and coming from someone who knows what he's

> doing:

>

>> Max level speed: mtv3=gt= v530=330kph

>> Mtv9 slower by 10 kph

>> Max cruise: mtv3=gt=v530=305kph

>> Mtv9 slower by 8 kph lia

>> Full power stall speed: V530=65 mph,mtv3=60 kph

>> Gt=50kph , MTV 9= < 50 kph(hovering possible)-below measurable airspeed

>> Vertical penetration from 6G pull,330kph:

>> V530=1600', mtv3=1700', GT=1700',Mtv9 00'

>> Time on vertical line: v530=17 second. Mtv3  second. GT 

>> seconds.MTV 9= >30 second (hovering).

>> Time to climb 1000' to 2000': v530  second.

>> GT= 20 second., mtv3=17 second, mtv9=17 seconds.

>> Level acceleration full power, 200kph to 300kph:

>> V530= 17sec. GT= 17sec. Mtv3=15 sec.mtv9=16 second.

>> Descent rate at idle with prop at 100%rpm:

>> Mtv9 =15 sec/1000',GT=32sec/1000',v530=35sec/1000',mtv3= 40sec/1000'

>> Note: the MTV 9 has longer blades and was optimized for static

>> thrust. It stays much flatter power off, is significantly slower in

>> speed, but will hover this weight aircraft.

>> The GT has more static thrust than the MTV3 and more thrust from 0 to

>> 120kph. It loses to the mtv3 at 170kph Vy climb and at 200-300kph

>> acceleration, but has same top speed and cruise speed. The GT power

>> off descent rate is high, suggesting the blades stay very flat at

>> power off .

>> The GT was only static balanced and was much lower vibration than the

>> v530 which had been dynamic balanced. The MTV3 and MTV9 had been

>> dynamic balanced and were by far the smoothest props. It would be

>> conceivable that the GT would be smoother if dynamic balanced. The GT

>> may need a spinner with backing plate to allow dynamic balancing to

>> the same level as a three blade prop. GT is developing a carbon fiber

>> spinner that is 46 cm wide for the V530 hub.

>> Vertical penetration and time on vertical line upwards were equal

>> with mtv3 vs GT.

>> From these tests, the GT is as good as the mtv3-250 three blade prop

>> during aerobatics and may be as good an all around prop for

>> aerobatics, travel, and short field take offs. The mtv9-260-29 has

>> been optimized for aerobatics and air shows at the expense of slower

>> cruise, max speed, and poor glide characteristics. It would be

>> advisable to test the GT against the MTV9-250 with both the-27 and

>> -29 blades.

>> The GT is superior to the v530 in static thrust, vertical

>> penetration, power on stall, and vibration. It is equal in climb,

>> midspeed acceration,cruise,and top speed. The GT has a slightly worse

>> power off glide than the v530. There is also more propeller braking

>> with the GT than with the V530 on roll out after landing.

>

> On Jan 19, 2011, at 4:43 AM, Richard.Goode wrote:

>

>> From everything I have heard I suspect that the GT blades do give a

>> good advantage over the V-530 blades.But then the V-530 is a 50+ year

>> old design,so a new blade really SHOULD perform a lot better!

>> But when is someone going to produce proper scientific performance

>> figures comparing these different props,including MT,rather than

>> saying that"acceleration is much better",or similar subjective

>> assesments??

>> Richard Goode Aerobatics

>> Rhodds Farm

>> Lyonshall

>> Hereford

>> HR5 3LW

>> United Kingdom

>> Tel: +44 (0) 1544 340120

>> Fax: +44 (0) 1544 340129

>> <http://www.russianaeros.com>www.russianaeros.com

>> <http://www.russianaeros.com>

>> Iâ€™m currently in Sri Lanka but this Mail is working,and my local

>> phone is +94 779 132 160.

>> *

>>

>> href="http://www.matronics.com/Navigator?Yak-List">http://www.matronics.com/Navigator?Yak-List

>> href="http://forums.matronics.com">http://forums.matronics.com

>> href="http://www.matronics.com/contribution">http://www.matronics.com/contribution

>>

>> *

>>

>

> *

>

> ===================================

> ef="http://www.matronics.com/Navigator?Yak-List">http://www.matronics.com/Navigator?Yak-List

> ===================================

> ums.matronics.com">http://forums.matronics.com

> ===================================

> http://www.matronics.com/contribution">http://www.matronics.com/contribution

> ===================================

>

> *

 *

 *

radiopicture

Joined: 23 Jun 2008
Posts: 263

Posted: Wed Jan 19, 2011 8:35 am Post subject: GT Propellors

No doubt of it. As Jill stated this need arose primarily due to a dearth of replacement blades, and not so much responding to a need for better performance. Having said this, the new offerings seem to be a step up in terms of balance and finish quality. I would also point out that performance of the props (including the three-blade MT) are surprisingly similar. 



On Jan 19, 2011, at 10:36 AM, A. Dennis Savarese wrote:



 	  Quote: 	
		   

 

 Now THAT's clearly one of the most intelligent comments on the subject of prop blades I've heard.  Thanks Doc for bringing me and probably some other folks on the list back down to earth.

 Dennis

 

 A. Dennis Savarese

 334-285-6263

 334-546-8182 (cell)

 Skype: Yakguy1

 www.yak-52.com

 

 On 1/19/2011 9:06 AM, Roger Kemp M.D. wrote:

> You know for the majority of us that are using our YAKs and CJs for

> weekend attitude adjustment the superiority

> Of which blade beats the other by 3 seconds is academic. Blades

> separating at the hub, serviceability,static vs

> Dynamic balance out of the box and overall safety of the blades are of

> great interest. Expense of replacement

> In this down turned economy is of greater interest. For those that need

> to replace blades, cost,reliability, and serviceability are big issues.

> How much damage to the M-14 do these new composite carbon fiber blades

> do to the M-14 when landed gear up at idle throttle? The reliable v530

> turns to saw dust without generally destroying the engine necessitating

> an expensive engine replacement. Any data out there on that?

> We YAK and CJ'ers are a cheap bunch you know?

> ?^))

> doc

> 

> Sent from my iPad

> 

> On Jan 19, 2011, at 4:56 AM, Eric Wobschall <eric(at)buffaloskyline.com

> <mailto:eric(at)buffaloskyline.com>> wrote:

> 

>> Richard:

>> 

>> I did find this data from Rick Volker, which I realize is anecdotal,

>> but I think still useful and coming from someone who knows what he's

>> doing:

>> 

>>> Max level speed: mtv3=gt= v530=330kph

>>> Mtv9 slower by 10 kph

>>> Max cruise: mtv3=gt=v530=305kph

>>> Mtv9 slower by 8 kph lia

>>> Full power stall speed: V530=65 mph,mtv3=60 kph

>>> Gt=50kph , MTV 9= < 50 kph(hovering possible)-below measurable airspeed

>>> Vertical penetration from 6G pull,330kph:

>>> V530=1600', mtv3=1700', GT=1700',Mtv9 00'

>>> Time on vertical line: v530=17 second. Mtv3  second. GT 

>>> seconds.MTV 9= >30 second (hovering).

>>> Time to climb 1000' to 2000': v530  second.

>>> GT= 20 second., mtv3=17 second, mtv9=17 seconds.

>>> Level acceleration full power, 200kph to 300kph:

>>> V530= 17sec. GT= 17sec. Mtv3=15 sec.mtv9=16 second.

>>> Descent rate at idle with prop at 100%rpm:

>>> Mtv9 =15 sec/1000',GT=32sec/1000',v530=35sec/1000',mtv3= 40sec/1000'

>>> Note: the MTV 9 has longer blades and was optimized for static

>>> thrust. It stays much flatter power off, is significantly slower in

>>> speed, but will hover this weight aircraft.

>>> The GT has more static thrust than the MTV3 and more thrust from 0 to

>>> 120kph. It loses to the mtv3 at 170kph Vy climb and at 200-300kph

>>> acceleration, but has same top speed and cruise speed. The GT power

>>> off descent rate is high, suggesting the blades stay very flat at

>>> power off .

>>> The GT was only static balanced and was much lower vibration than the

>>> v530 which had been dynamic balanced. The MTV3 and MTV9 had been

>>> dynamic balanced and were by far the smoothest props. It would be

>>> conceivable that the GT would be smoother if dynamic balanced. The GT

>>> may need a spinner with backing plate to allow dynamic balancing to

>>> the same level as a three blade prop. GT is developing a carbon fiber

>>> spinner that is 46 cm wide for the V530 hub.

>>> Vertical penetration and time on vertical line upwards were equal

>>> with mtv3 vs GT.

>>> From these tests, the GT is as good as the mtv3-250 three blade prop

>>> during aerobatics and may be as good an all around prop for

>>> aerobatics, travel, and short field take offs. The mtv9-260-29 has

>>> been optimized for aerobatics and air shows at the expense of slower

>>> cruise, max speed, and poor glide characteristics. It would be

>>> advisable to test the GT against the MTV9-250 with both the-27 and

>>> -29 blades.

>>> The GT is superior to the v530 in static thrust, vertical

>>> penetration, power on stall, and vibration. It is equal in climb,

>>> midspeed acceration,cruise,and top speed. The GT has a slightly worse

>>> power off glide than the v530. There is also more propeller braking

>>> with the GT than with the V530 on roll out after landing.

>> 

>> On Jan 19, 2011, at 4:43 AM, Richard.Goode wrote:

>> 

>>> From everything I have heard I suspect that the GT blades do give a

>>> good advantage over the V-530 blades.But then the V-530 is a 50+ year

>>> old design,so a new blade really SHOULD perform a lot better!

>>> But when is someone going to produce proper scientific performance

>>> figures comparing these different props,including MT,rather than

>>> saying that"acceleration is much better",or similar subjective

>>> assesments??

>>> Richard Goode Aerobatics

>>> Rhodds Farm

>>> Lyonshall

>>> Hereford

>>> HR5 3LW

>>> United Kingdom

>>> Tel: +44 (0) 1544 340120

>>> Fax: +44 (0) 1544 340129

>>> <http://www.russianaeros.com>www.russianaeros.com

>>> <http://www.russianaeros.com>

>>> I’m currently in Sri Lanka but this Mail is working,and my local

>>> phone is +94 779 132 160.

>>> *

>>> 

>>> href="http://www.matronics.com/Navigator?Yak-List">http://www.matronics.com/Navigator?Yak-List

>>> href="http://forums.matronics.com">http://forums.matronics.com

>>> href="http://www.matronics.com/contribution">http://www.matronics.com/contribution

>>> 

>>> *

>>> 

>> 

>> *

>> 

>> ===================================

>> ef="http://www.matronics.com/Navigator?Yak-List">http://www.matronics.com/Navigator?Yak-List

>> ===================================

>> ums.matronics.com">http://forums.matronics.com

>> ===================================

>> http://www.matronics.com/contribution">http://www.matronics.com/contribution

>> ===================================

>> 

>> *

> *

> 

> 

> *

wise(at)txc.net.au
Guest

Posted: Wed Jan 19, 2011 12:09 pm Post subject: GT Propellors

Strong rumour suggests that this was the result of a birdstrike???

Chris.

 

From: owner-yak-list-server(at)matronics.com [mailto:owner-yak-list-server(at)matronics.com] On Behalf Of Olivier Vigneron

Sent: Wednesday, 19 January 2011 9:13 PM

To: yak-list(at)matronics.com

Subject: Re: GT Propellors



 

I found something not so good about the GT Prop: http://gtpropellers.com/

 



Of course a problem is always a possibility but the AAIB's conclusions are very bad:



http://www.aaib.gov.uk/publications/bulletins/september_2009/speedtwin_st2__g_stdl.cfm



 



Olivier

2011/1/19 Richard.Goode <richard.goode(at)russianaeros.com (richard.goode(at)russianaeros.com)>

From everything I have heard I suspect that the GT blades do give a good advantage over the V-530 blades.But then the V-530 is a 50+ year old design,so a new blade really SHOULD perform a lot better!



But when is someone going to produce proper scientific performance figures comparing these different props,including MT,rather than saying that"acceleration is much better",or similar subjective assesments??



Richard Goode Aerobatics 

Rhodds Farm 

Lyonshall 

Hereford 

HR5 3LW 

United Kingdom 



 



Tel:   +44 (0) 1544 340120 

Fax:  +44 (0) 1544 340129 

www.russianaeros.com

I’m currently in Sri Lanka but this Mail is working,and my local phone is +94 779 132 160.



 



 

 	  Quote: 	
		    et="_blank">http://www.matronics.com/Navigator?Yak-Listtp://forums.matronics.com_blank">http://www.matronics.com/contribution  	


 

 	  Quote: 	
		     	
0 	  Quote: 	
		   	
1 	  Quote: 	
		   	
2 	  Quote: 	
		   	
3 	  Quote: 	
		   	
4 	  Quote: 	
		   	
5 	  Quote: 	
		   	
6 	  Quote: 	
		   	
7 	  Quote: 	
		   	
8 	  Quote: 	
		   	
9 	  Quote: 	
		  et="_blank">http://www.matronics.com/Navigator?Yak-List 	
0 	  Quote: 	
		  et="_blank">http://www.matronics.com/Navigator?Yak-List 	
1 	  Quote: 	
		  et="_blank">http://www.matronics.com/Navigator?Yak-List 	
2 	  Quote: 	
		  et="_blank">http://www.matronics.com/Navigator?Yak-List 	
3

  [quote][b]

rick(at)rvairshows.com
Guest

Posted: Wed Jan 19, 2011 12:48 pm Post subject: GT Propellors

How about using less fuel at a given airspeed, better resistance to stones and rain, smoother balance out of the box, utility of using the original hub, or saving brakes due to better prop braking, increased safety in shorter take off roll? Throw in ease of repair. The GT prop does all these things better to appeal to those light in the wallet. Better Climb and cruise performance yields economy.  I agree that the MT prop is overkill for most Yak/CJ owners.Rick VOLKER

Sent from my Verizon Wireless BlackBerryFrom:  "Roger Kemp M.D." <viperdoc(at)mindspring.com> 

Sender:  owner-yak-list-server(at)matronics.com 

Date: Wed, 19 Jan 2011 09:06:17 -0600

To: yak-list(at)matronics.com<yak-list(at)matronics.com>

ReplyTo:  yak-list(at)matronics.com

Subject: Re: Yak-List: GT Propellors

You know for the majority of us that ar= e using our YAKs and CJs for weekend attitude adjustment the superiorityOf which blade beats the other by 3 seconds is academic. Blades separ= ating at the hub, serviceability,static vs 

Dynamic balance o= ut of the box and overall safety of the blades are of great interest. Expens= e of replacement

In this down turned economy is of greater interes= t. For those that need to replace blades, cost,reliability, and serviceabili= ty are big issues. How much damage to the M-14 do these new composite carbon=  fiber blades do to the M-14 when landed gear up at idle throttle? The relia= ble v530 turns to saw dust without generally destroying the engine necessita= ting an expensive engine replacement. Any data out there on that? We YAK and CJ'ers are a cheap bunch you know?

?^))

doc

Sent from my iPad

On Jan 19, 2011, at 4:56 AM, Eri= c Wobschall <eric(at)buffaloskyli= ne.com (eric(at)buffaloskyline.com)> wrote:

[quote]Richard:

I did find this data from Rick Volker, which I r= ealize is anecdotal, but I think still useful and coming from someone who kn= ows what he's doing:

 	  Quote: 	
		  Max=  level speed: mtv3=3Dgt=3D v530=3D330kph

Mtv9 slower by 10 kph&= nbsp;

Max cruise: mtv3=3Dgt=3Dv530=3D305kph

Mtv9 sl= ower by 8 kph lia 

Full power stall speed: V530=3D65 mph,mt= v3=3D60 kph 

Gt=3D50kph , MTV 9=3D < 50 kph(hovering po= ssible)-below measurable airspeed

Vertical penetration from 6G p= ull,330kph:

V530=3D1600', mtv3=3D1700', GT=3D1700',Mtv9=3D2000'= 

Time on vertical line: v530=3D17 second. Mtv3=3D20 second. GT=3D= 20 seconds.MTV 9=3D >30 second (hovering).

Time to climb 100= 0' to 2000': v530=3D20 second.

GT=3D 20 second., mtv3=3D17 seco= nd, mtv9=3D17 seconds.

Level acceleration full power, 200kph to=  300kph:

V530=3D 17sec. GT=3D 17sec. Mtv3=3D15 sec.mtv9=3D16 se= cond. 

Descent rate at idle with prop at 100%rpm:</= div>Mtv9 =3D15 sec/1000',GT=3D32sec/1000',v530=3D35sec/1000',mtv3=3D 40sec/= 1000'

Note: the MTV 9 has longer blades and was optimized for st= atic thrust. It stays much flatter power off, is significantly slower in spe= ed, but will hover this weight aircraft. 

The GT has more s= tatic thrust than the MTV3 and more thrust from 0 to 120kph. It loses to the=  mtv3 at 170kph Vy climb and at 200-300kph acceleration, but has same top sp= eed and cruise speed. The GT power off descent rate is high, suggesting the b= lades stay very flat at power off . 

The GT was only stati= c balanced and was much lower vibration than the v530 which had been dynamic=  balanced. The MTV3 and MTV9 had been dynamic balanced and were by far the s= moothest props. It would be conceivable that the GT would be smoother if dyn= amic balanced. The GT may need a spinner with backing plate to allow dynamic=  balancing to the same level as a three blade prop.  GT is developing a=  carbon fiber spinner that is 46 cm wide for the V530 hub. Vertical penetration and time on vertical line upwards were equal with mtv3=  vs GT. 

=46rom these tests, the GT is as good as the mtv3-2= 50 three blade prop during aerobatics and may be as good an all around prop f= or aerobatics, travel, and short field take offs. The mtv9-260-29 has been o= ptimized for aerobatics and air shows at the expense of slower cruise, max s= peed, and poor glide characteristics. It would be advisable to test the GT a= gainst the MTV9-250 with both the-27 and -29 blades.

The GT is su= perior to the v530 in static thrust, vertical penetration, power on stall, a= nd vibration. It is equal in climb, midspeed acceration,cruise,and top speed= . The GT has a slightly worse power off glide than the v530.  There is a= lso more propeller braking with the GT than with the V530 on roll out after l= anding.

On J= an 19, 2011, at 4:43 AM, Richard.Goode wrote:

 	  Quote: 	
		  =46rom everything I have heard I suspect that the GT blades do give a goo= d advantage over the V-530 blades.But then the V-530 is a 50+ year old desig= n,so a new blade really SHOULD perform a lot better!

But when is someone going to produce proper scienti= fic performance figures comparing these different props,including MT,rather t= han saying that"acceleration is much better",or similar subjective assesment= s??

Richard Goode Aerobatic= s 

Rhodds Farm 

Lyonshall 

Hereford 

HR5 3LW 

United Kingdom

Tel:   +44 (0) 1544 340120 

Fax:  +44 (0) 1544 340129 

= www.russianaeros.com

I=E2= =80=99m currently in Sri Lanka but this Mail is working,and my local phone i= s +94 779 132 160.

 	  Quote: 	

href=3D"http://www.m=

atronics.com/Navigator?Yak-List">http://www.matronics.com/Navigator?Yak-List

href=3D"http://forums.matronics.com<=

/a>">http://forums.matronics.com<=

/a>

href=3D"http://www.matroni=

cs.com/contribution">http://www.matronics.com/contribution

<=

/font> 	

  	  Quote: 	

=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=

=3D=3D=3D=3D=3D=3D=3D=3D=3D

ef=3D"http://www.matronics.com/Navigator?Yak-List">http://www.matronics.com/=

Navigator?Yak-List

=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=

=3D=3D=3D=3D=3D=3D=3D=3D=3D

ums.matronics.com">http://forums.matronics.com

=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=

=3D=3D=3D=3D=3D=3D=3D=3D=3D

http://www.matronics.com/contribution">http://www.matronics.com/contribution=

=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=

=3D=3D=3D=3D=3D=3D=3D=3D=3D

<=

/font> 	

=  [quote][b]

cpayne(at)joimail.com
Guest

Posted: Wed Jan 19, 2011 5:05 pm Post subject: GT Propellors

Remarkable! Same sorta experience I had with email to GT propellers rep named  "Humberto". Me no speakee english I guess.



Craig Payne

Display posts from previous:

	Matronics Email Lists Forum Index -> Yak-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