Bill_H
Well Known Member
This is a wish list. For details about adjusting the stock RV12 prop, see http://www.vansairforce.com/community/showthread.php?t=59682
Generally it is at least a half hour process, not something to be done frequently!
The standard RV12 propellor is WAAAAAAAAYYYYYYY too finicky to adjust. Clamping, digital levels, home-made brackets, and the fact that 0.3 degrees of adjustment makes a significant performance difference, but is just about the minimum change that can be consistently made. Plus the difficulty of ensuring both blades are set as closely alike as possible. Each blade must be adjusted separately, the pin-slot mechanism has way too much slop to accurately adjust both at once.
Now, the newer Sensenich Pitch Pin Hub System method involving rotating the blade to a stop against a selectable pre-milled pin sounds much better! But, in practice does it work as easily as is claimed? Is it exact? I don't know. A 3 blade version with the pin system is available for the RV12 but one report is that the individual blades still need fine tuning after using the pin system.
So PRECISION, CONSISTENCY, and EASE in the adjustment are VERY important design parameters!
I operate out of a short grass strip. So I am slightly pitched for climb for the takeoff, landing is not an issue. Not ideal for a long x-c. It would be nice to take off, land at a nearby airport, QUICKLY and EASILY repitch, and leave the prop in cruise of the rest of the trip. Repitch for climb when back home.
Now it is my understanding that an ELSA can NEVER EVER have an in-flight adjustable prop, either manual or constant speed. And in fact if such a prop is mounted (and discovered), I have "heard" the registration can be "voided" and never recovered (???!!!) Knowledgeable comments on this urban legend please!
Option 1 - But imagine an ELECTRICALLY adjustable prop. Mount the adjustment switch so it is reachable only through the oil door. Ideal!
Option 2 could be after a careful regulatory review to mount the switch in the cockpit but placarded "not to be used in flight."
(Option 3 which exists only in an imaginary universe is a secret hidden switch or pocket remote control...)
The adjustment mechanism would have to be precise enough to always be moving both blades in unison and keeping them to a very close tolerance! Obviously a cockpit indicator element is needed.
A quick search shows the following. Having only built 1 ELSA RV12 I am not very knowledgeable about props!
Italian company, almost no detailed info on the website:
http://www.gt-propellers.com/variable-pitch-propellers.html
Czech company: http://www.woodcomp.cz/en/sr3000-3.php or http://www.woodcomp.cz/en/sr3000-2.php and http://adcompair.com/propellers/propellers1.htm
California - but 15 pounds? http://www.ivoprop.com/inflightmediummodel.htm
Has anyone else done any research or investigation in this area? anything like this in the ROTAX-LSA world?
Generally it is at least a half hour process, not something to be done frequently!
The standard RV12 propellor is WAAAAAAAAYYYYYYY too finicky to adjust. Clamping, digital levels, home-made brackets, and the fact that 0.3 degrees of adjustment makes a significant performance difference, but is just about the minimum change that can be consistently made. Plus the difficulty of ensuring both blades are set as closely alike as possible. Each blade must be adjusted separately, the pin-slot mechanism has way too much slop to accurately adjust both at once.
Now, the newer Sensenich Pitch Pin Hub System method involving rotating the blade to a stop against a selectable pre-milled pin sounds much better! But, in practice does it work as easily as is claimed? Is it exact? I don't know. A 3 blade version with the pin system is available for the RV12 but one report is that the individual blades still need fine tuning after using the pin system.
So PRECISION, CONSISTENCY, and EASE in the adjustment are VERY important design parameters!
I operate out of a short grass strip. So I am slightly pitched for climb for the takeoff, landing is not an issue. Not ideal for a long x-c. It would be nice to take off, land at a nearby airport, QUICKLY and EASILY repitch, and leave the prop in cruise of the rest of the trip. Repitch for climb when back home.
Now it is my understanding that an ELSA can NEVER EVER have an in-flight adjustable prop, either manual or constant speed. And in fact if such a prop is mounted (and discovered), I have "heard" the registration can be "voided" and never recovered (???!!!) Knowledgeable comments on this urban legend please!
Option 1 - But imagine an ELECTRICALLY adjustable prop. Mount the adjustment switch so it is reachable only through the oil door. Ideal!
Option 2 could be after a careful regulatory review to mount the switch in the cockpit but placarded "not to be used in flight."
(Option 3 which exists only in an imaginary universe is a secret hidden switch or pocket remote control...)
The adjustment mechanism would have to be precise enough to always be moving both blades in unison and keeping them to a very close tolerance! Obviously a cockpit indicator element is needed.
A quick search shows the following. Having only built 1 ELSA RV12 I am not very knowledgeable about props!
Italian company, almost no detailed info on the website:
http://www.gt-propellers.com/variable-pitch-propellers.html
Czech company: http://www.woodcomp.cz/en/sr3000-3.php or http://www.woodcomp.cz/en/sr3000-2.php and http://adcompair.com/propellers/propellers1.htm
California - but 15 pounds? http://www.ivoprop.com/inflightmediummodel.htm
Has anyone else done any research or investigation in this area? anything like this in the ROTAX-LSA world?
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