|
Matronics Email Lists Web Forum Interface to the Matronics Email Lists
|
View previous topic :: View next topic |
Author |
Message |
pmccand(at)yahoo.com Guest
|
Posted: Thu Jul 10, 2008 5:44 am Post subject: Constant speed prop |
|
|
Pete,
I am talking specifically about the Airmaster constant speed (variable pitch) prop. Find it at http://www.propellor.com/
I find it interesting that when one brand of adjustable prop was tried on the Esqual there was a 12 mph LOSS in speed as compared to the woodie prop. That only means one thing... that the maximum pitch on the prop used is less than the fixed pitch of the wooded one. I bet that if apples were compared to apples (inches to inches), we might get at least the same performance at cruise and perhaps better if the pitch was increased over the fixed version.
On the Airmaster website, there are specifications for a Jabiru 3300 on an esqual. Performance reports for the esqual are only for the Rotax 912S engine, but Bert Flood in Australia used an Airmaster AP332 on his plane and reported:
"I am really pleased with the Airmaster propeller, it performs really well. Cruise at 75% power is 130kts with a climb of 1200ft/m. Top speed is now 148kts. It¢s really great to fly."
Airmaster has a lot of application specs for aircraft using the Jabiru 3300 engine including the Storm, Esqual, Jabiru, and 20+ installations. That's why I am asking...Just haven't head of anyone trying this on the Lightning.
Phil Mc C a n d l e ss
Quote: | Quote: | What type of constant speed prop set up are you talking about? Who is themanufacturer? |
|
[quote][b]
| - The Matronics Lightning-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?Lightning-List |
|
|
|
Back to top |
|
|
pete(at)flylightning.net Guest
|
Posted: Thu Jul 10, 2008 6:40 am Post subject: Constant speed prop |
|
|
It was possible to put much more pitch into the airmaster than the wood prop. The problem lies with the Warp Drive blades and their airfoil profile. Turning them at 2000 to 2300 as would happen on a Rotax seems to work well on an Esqual although we could duplicate Bert Flood’s speed numbers on our Esqual with the 80 hp Jabiru and wood prop.
When you try to turn the Warp blades at 2850 to 3000 rpm as you would on a Jabiru they lose so much efficiency that the induced drag of the blades eat up the hp that would otherwise be converted to speed. We’ve seen the same thing with Jabiru Aircraft. Andy Silvester had an Airmaster on the J400 while we had a Sensenich Wood on our J200. Andy had a small advantage in climb but no advantage in speed or fuel economy.
Several have tried airmaster or MT in flight adjustables on Europa’s with no speed advantage over a good wood prop. In fact there are Jabiru powered Europa’s with wood props that are significantly faster than the variable prop versions.
Based on our experience an airmaster is unproductive extra expense.
Pete
From: owner-lightning-list-server(at)matronics.com [mailto:owner-lightning-list-server(at)matronics.com] On Behalf Of Phil McCandless
Sent: Thursday, July 10, 2008 8:42 AM
To: Lightning-List Digest List; lightning-list(at)matronics.com
Subject: Re: Constant speed prop
Pete,
I am talking specifically about the Airmaster constant speed (variable pitch) prop. Find it at http://www.propellor.com/
I find it interesting that when one brand of adjustable prop was tried on the Esqual there was a 12 mph LOSS in speed as compared to the woodie prop. That only means one thing... that the maximum pitch on the prop used is less than the fixed pitch of the wooded one. I bet that if apples were compared to apples (inches to inches), we might get at least the same performance at cruise and perhaps better if the pitch was increased over the fixed version.
On the Airmaster website, there are specifications for a Jabiru 3300 on an esqual. Performance reports for the esqual are only for the Rotax 912S engine, but Bert Flood in Australia used an Airmaster AP332 on his plane and reported:
[b][b] [/b]
[b]"[/b][/b]I am really pleased with the Airmaster propeller, it performs really well. Cruise at 75% power is 130kts with a climb of 1200ft/m. Top speed is now 148kts. It¢s really great to fly."
Airmaster has a lot of application specs for aircraft using the Jabiru 3300 engine including the Storm, Esqual, Jabiru, and 20+ installations. That's why I am asking...Just haven't head of anyone trying this on the Lightning.
Phil Mc C a n d l e ss
Quote: |
What type of constant speed prop set up are you talking about? Who is the
manufacturer?
|
Quote: | http://www.matronics.com/Navigator?Lightning-List | 01234567890
[quote][b]
| - The Matronics Lightning-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?Lightning-List |
|
|
|
Back to top |
|
|
Kayberg(at)aol.com Guest
|
Posted: Thu Jul 10, 2008 7:36 am Post subject: Constant speed prop |
|
|
In a message dated 7/10/2008 10:41:41 A.M. Eastern Daylight Time, pete(at)flylightning.net writes:
Quote: |
It was possible to put much more pitch into the airmaster than the wood prop. The problem lies with the Warp Drive blades and their airfoil profile. Turning them at 2000 to 2300 as would happen on a Rotax seems to work well on an Esqual although we could duplicate Bert Flood’s speed numbers on our Esqual with the 80 hp Jabiru and wood prop. |
Our experience with Warp Drive was similar on other aircraft. The great virtue for Warp Drive is in water environments, not for top speed. Even with Rotax 912 series the top end suffered. A three blade IVO delivered the best thrust at low speed and best (with inflight adjust) top speed.
but I would not put an IVO on a Jabiru engine for all the tea in China.
A recent experience at Green Landings showed the latest design Sensnich wood prop on a Lightning added 10 mph or more along with better climb (slightly longer takeoff) over the ground adjust composite Sensnich.
It's an easy decision.
Doug Koenigsberg
Get the scoop on last night's hottest shows and the live music scene in your area - Check out TourTracker.com!
[quote][b]
| - The Matronics Lightning-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?Lightning-List |
|
|
|
Back to top |
|
|
Clive J
Joined: 03 Nov 2007 Posts: 340 Location: UK
|
Posted: Thu Jul 10, 2008 9:23 am Post subject: Constant speed prop |
|
|
Doug, what is the 'latest design' Sensenich? A new profile? How new?
Regards, Clive
--
| - The Matronics Lightning-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?Lightning-List |
|
|
|
Back to top |
|
|
Kayberg(at)aol.com Guest
|
Posted: Thu Jul 10, 2008 2:52 pm Post subject: Constant speed prop |
|
|
In a message dated 7/10/2008 1:24:42 P.M. Eastern Daylight Time, clive.james(at)uk.bp.com writes:
Quote: | --> Lightning-List message posted by: "James, Clive R" <clive.james(at)uk.bp.com>
Doug, what is the 'latest design' Sensenich? A new profile? How new?
Regards, Clive
|
It is the "FZ" if memory serves. It is the prop Buz and Nick have been testing on the prototype and the demonstrator.
It is new in the sense that it has been out for about 8 months. It is the first time we have used one on a Green Landings build. Jim's Lightning will have one also.... he should be approved for first flight after this weekend.
Doug
Get the scoop on last night's hottest shows and the live music scene in your area - Check out TourTracker.com!
[quote][b]
| - The Matronics Lightning-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?Lightning-List |
|
|
|
Back to top |
|
|
pequeajim
Joined: 03 Sep 2006 Posts: 708 Location: New Holland, PA
|
Posted: Thu Jul 10, 2008 3:06 pm Post subject: Constant speed prop |
|
|
CAN'T WAIT!!
On 7/10/08, Kayberg(at)aol.com (Kayberg(at)aol.com) <Kayberg(at)aol.com (Kayberg(at)aol.com)> wrote: [quote] In a message dated 7/10/2008 1:24:42 P.M. Eastern Daylight Time, clive.james(at)uk.bp.com (clive.james(at)uk.bp.com) writes:
Quote: | --> Lightning-List message posted by: "James, Clive R" <clive.james(at)uk.bp.com (clive.james(at)uk.bp.com)>
Doug, what is the 'latest design' Sensenich? A new profile? How new?
Regards, Clive
|
It is the "FZ" if memory serves. It is the prop Buz and Nick have been testing on the prototype and the demonstrator.
It is new in the sense that it has been out for about 8 months. It is the first time we have used one on a Green Landings build. Jim's Lightning will have one also.... he should be approved for first flight after this weekend.
Doug
Get the scoop on last night's hottest shows and the live music scene in your area - Check out TourTracker.com!
[b]
| - The Matronics Lightning-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?Lightning-List |
|
|
|
Back to top |
|
|
dashvii(at)hotmail.com Guest
|
Posted: Thu Jul 10, 2008 5:20 pm Post subject: Constant speed prop |
|
|
Phil,
None of these are new questions. Generally speaking I think that you're much better off with less blades. That is unless you have enough power and need more blades because a 2 blader would be too long. Don't underestimate the difference in rotational mass either. Those wood props are something like 5 pounds and I think the ground adjustable is like 25 pounds. I would also think that changes in RPM would be easier on the internal stresses of the engine with the wooden prop. A huge factor in my mind would be that the cost is very small for a good wooden prop. The craftsmanship also appeals to me. Finally, you are very likely that if you get a prop strike with a wooden prop that you won't have to rebuild the engine. Just my .02
Brian W.
_________________________________________________________________
Need to know now? Get instant answers with Windows Live Messenger.
http://www.windowslive.com/messenger/connect_your_way.html?ocid=TXT_TAGLM_WL_messenger_072008
| - The Matronics Lightning-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?Lightning-List |
|
|
|
Back to top |
|
|
jhausch
Joined: 14 Jan 2008 Posts: 35
|
Posted: Fri Jul 11, 2008 3:13 am Post subject: Re: Constant speed prop |
|
|
I wonder if the weight difference causes a fwd cg shift which would adversely affect the cruise speed?
| - The Matronics Lightning-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?Lightning-List |
|
|
|
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 cannot download files in this forum
|
Powered by phpBB © 2001, 2005 phpBB Group
|