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The Ultimate RV-12 Prop?

Bill_H

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?
 
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Bill_H said:
David - I see the 3 blade with pitch pin system. So you have to use that system then fine tune each blade individually? By individually loosening the clamping bolts and using the level like we are used to? How close does the pin system get the blades? How about posting a comprehensive review of it?
Click to expand...

Bill - ;

The pin system works well, I just check for accuracy. Playing with the pitch settings I sometimes like to go between a 3 & 4, so the digital measurements are nice. To set the pitch loosen the bolts, insert the correct pin, turn the blade till the stop hits the pin and tighten.

See the red comments on the picture below.

3blade capture.JPG


two different setting listed below

pitch Capture.JPG


Not too detailed, but quick answer
 
Bump this thread. Mel or others -
Now, under the new medical rules, many pilots with expired medicals can fly an EAB, that were formerly restricted to ELSA or SLSA.

So a major "need" for the RV12 to be registered as ELSA has gone away, as well as the need to keep one within LSA parameters.

Questions:

1. Can an already ELSA-registered RV12 be re-registered as an EAB?
2. Even if no changes were made? (Like converting an SLSA to an ELSA.)
3. Would that change eliminate the ELSA builder from having annual inspection signoff authorization?
4. Would that require a 40hr return to Phase 1?

5. Would a CS or manually-electrically adjustable prop installed on an ELSA-registered RV12 simultaneously need to also include such re-registering? (Please also address the "urban legend" issue in the original post.)
6. Would that mod then require a 40-hr return to Phase 1?
7. Recommendations for such a prop anyone? (See original post)
 
Doing any mod to an E-LSA that would make it not meet a LSA requirement (in this case no cockpit controllable propeller) would make it's C of A immediately invalid.

There is no approved path that I know of that would allow a non conforming E-LSA be re-certified as an E-AB.

Regarding the newer propeller pitch setting process?
It is better, but still not precise enough in my opinion.
 
rvbuilder2002 said:
Doing any mod to an E-LSA that would make it not meet a LSA requirement (in this case no cockpit controllable propeller) would make it's C of A immediately invalid.

There is no approved path that I know of that would allow a non conforming E-LSA be re-certified as an E-AB.

Regarding the newer propeller pitch setting process?
It is better, but still not precise enough in my opinion.
Click to expand...

Of course this begs the question: "What if it was built as an EAB in the first place?"

It'll be interesting to see what sort of side effects this new medical rule might spin off.

Jim
 
Sport pilots and private pilots flying under sport pilot rules have always been allowed to fly light sport aircraft no matter how they were registered, whether type certificated, E-AB, E-LSA, or S-LSA. So that was never a reason to register as E-LSA. The only sport pilot requirement is that the aircraft they fly must meet the definition of LSA.
An E-LSA can not be re-registered as E-AB. Making changes to an E-LSA, that results in it no longer meeting the definition of LSA, might make it illegal to ever fly again. Mel?
 
Jim T said:
Of course this begs the question: "What if it was built as an EAB in the first place?"

It'll be interesting to see what sort of side effects this new medical rule might spin off.

Jim
Click to expand...

In that case it would not be a problem as long as all requirements stipulated by the aircraft's operating limitations regarding a propeller change are met.

After the propeller change the airplane would require at least a private license (no sport pilots).
 
An SLSA or ELSA my NOT be reregistered as EAB:

#1 It was not shown to be Amateur-Built (51%).
#2 It did not fly a 40 hr. phase I flight test program.

If an SLSA or ELSA is modified in a way to make it not LSA compliant, It's airworthiness certificate immediately becomes invalid with no path back.

An RV-12 originally registered and certificated as EAB may be converted to a controllable prop, but it can never again be flown by a sport pilot or any other pilot operating under sport pilot privileges.
 
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Mel said:
An SLSA or ELSA my NOT be reregistered as EAB:

#1 It was not shown to be Amateur-Built (51%).
#2 It did not fly a 40 hr. phase I flight test program.

If an SLSA or ELSA is modified in a way to make it not LSA compliant, It's airworthiness certificate immediately becomes invalid with no path back.

An RV-12 originally registered and certificated as EAB may be converted to a controllable prop, but it can never again be flown by a sport pilot or any other pilot operating under sport pilot privileges.
Click to expand...

Mel, Still trying to understand all of this.

What if 1). a builder could prove they built over 51% of an RV 12 that they built as an ELSA and
2). They were willing to do a 40 hr. flyoff

Could it then be re-documented as an EAB?

Hope that makes sense. I still have a hard time grasping the idea that a perfectly flyable airplane can become unflyable legally if you do certain changes.

Jim
 
Jim T said:
Mel, Still trying to understand all of this.
What if 1). a builder could prove they built over 51% of an RV 12 that they built as an ELSA and
2). They were willing to do a 40 hr. flyoff
Could it then be re-documented as an EAB?
Hope that makes sense. I still have a hard time grasping the idea that a perfectly flyable airplane can become unflyable legally if you do certain changes.
Jim
Click to expand...

Sorry but that's the way it is.
 
Mel said:
Sorry but that's the way it is.
Click to expand...

This issue regarding a electrically controlled pitch prop....Mel, if it doesn't take a e-lsa out of performance standards "and is only switchable from outside the cockpit".

Would that effect aircraft certification? Sorry to beat this horse to death, but this has been a question I've had also!!!
 
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Phantom30 said:
This issue regarding a electrically controlled pitch prop....Mel, if it doesn't take a e-lsa out of performance standards "and is only switchable from outside the cockpit".
Would that effect aircraft certification? Sorry to beat this horse to death, but this has been a question I've had also!!!
Click to expand...

If the switch is outside of the cockpit and cannot be operated from the cockpit, that's considered as "ground adjustable" and is acceptable.

I've actually done a couple of aircraft like this.
 
How about if I put the switch INSIDE the cockpit with a big sign saying"Never touch this switch when the aircraft is in motion"? This would allow me to be a safer pilot by setting the pitch to match the runway, temperature and obstacles during that takeoff, surely the FAA would be concerned about flight safety and allow this. I would of course then land on a longer runway to adjust it back to cruise pitch for the rest of the trip home.
 
DonFromTX said:
How about if I put the switch INSIDE the cockpit with a big sign saying"Never touch this switch when the aircraft is in motion"? This would allow me to be a safer pilot by setting the pitch to match the runway, temperature and obstacles during that takeoff, surely the FAA would be concerned about flight safety and allow this. I would of course then land on a longer runway to adjust it back to cruise pitch for the rest of the trip home.
Click to expand...

That decision couldn't be made just as well at the ramp during your preflight?
 
DonFromTX said:
How about if I put the switch INSIDE the cockpit with a big sign saying"Never touch this switch when the aircraft is in motion"? This would allow me to be a safer pilot by setting the pitch to match the runway, temperature and obstacles during that takeoff, surely the FAA would be concerned about flight safety and allow this. I would of course then land on a longer runway to adjust it back to cruise pitch for the rest of the trip home.
Click to expand...

Sorry that won't work. That would be similar to flying a Rocket with a placard that said "Never exceed 120 kts CAS".
 
Just some background.
The FAA is not the one that placed the in-flight adjustable prop limitations. It was the 4 big players during the inception from the fat Ultralight community that specified that. You can read this in the original preamble during the inception of the LSA rules. The FAA didn't care.

The other item is it is okay to have an in-flight adjustable prop so long as you can not access it during a flight. If the switch is in fact in the cowl and you must be on the ground to adjust it it does fit the definition of a ground adjustable prop. This was confirmed by the top people at the FAA.

That said if the switch is in to cowl and not usable in air it would be an absolute waste of the prop's in-flight qualities and capabilities. Kind of defeats the purpose of an in-flight adjustable prop that's sole purpose is to complement the engine and aircraft performance and you just negated that and now you have additional cost and maint.
 
AeroDog said:
Kinda like the big-engined LSA Carbon Cub.
Click to expand...

Almost nearly but not quite hardly!

In the case of the Carbon Cub, the engine manufacture set the usable hp limits. It's not simply an instrument panel placard.
 
So all we need is a prop maker that would put a sticker on the prop that it is "Not to Be Adjusted in Flight" and they could sell them to almost every RV12 person and it would be legal, right?
Unless some FAA guy was flying very close to you, nobody would ever know you touched it.

QUOTE=Mel;1096151]Almost nearly but not quite hardly!

In the case of the Carbon Cub, the engine manufacture set the usable hp limits. It's not simply an instrument panel placard.[/QUOTE]
 
DonFromTX said:
So all we need is a prop maker that would put a sticker on the prop that it is "Not to Be Adjusted in Flight" and they could sell them to almost every RV12 person and it would be legal, right?
Unless some FAA guy was flying very close to you, nobody would ever know you touched it.

AND jump through all of the FAA "hoops" that Carbon Cub did to get the approval. Good luck.
Click to expand...
 
Why do so many people want to "push" the rules? If you want to "cheat", go ahead. You probably won't get caught.
Just don't publish your intentions on the internet.
We have a lot of freedom here. If we insist on abusing the privileges we have, they can go away.
 
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Mel said:
Why do so many people want to "push" the rules? If you want to "cheat", go ahead. You probably won't get caught.
Just don't publish your intentions on the internet.
We have a lot of freedom here. If we insist on abusing the privileges we have, they can go away.
Click to expand...

Mel, first and foremost, must of us are smart enough not to abuse "the rule" (and take the chance of loosing our flying privilege); that said, it is kind of stupid when the technology exsists to achieve better flight performance. Rules should make sense!
 
Phantom30 said:
Mel, first and foremost, must of us are smart enough not to abuse "the rule" (and take the chance of loosing our flying privilege); that said, it is kind of stupid when the technology exsists to achieve better flight performance. Rules should make sense!
Click to expand...

The reasoning for not allowing a controllable prop in LSA is to make the operation of the aircraft as simple as possible.
With the speed range of light sport aircraft a controllable prop just doesn't buy you that much performance.
While a typical RV has a speed range of right at 4:1, LSA limits the aircraft to a range of 2.7:1.
 
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You can not have any control device or switch in the cockpit that would allow a pilot access labeled or not. According to the FAA it has to be ONLY accessible and changeable on the ground. The rules for LSA were set up by the big 4 pushing for LSA during the fat Ultralight days. The FAA never dis-allowed it. You can't blame the FAA for this one.
 
Sink said:
You can not have any control device or switch in the cockpit that would allow a pilot access labeled or not. According to the FAA it has to be ONLY accessible and changeable on the ground. The rules for LSA were set up by the big 4 pushing for LSA during the fat Ultralight days. The FAA never dis-allowed it. You can't blame the FAA for this one.
Click to expand...

Roger,
I'm not sure who the BIG 4 is that you keep referring too because the consensus standard was developed by an ASTM committee of which there were far more than 4 members (that is why it is refered to as a consensus standard). I believe there was and still is at least one representative of the FAA as a committee member (Van's Aircraft is a participating member of the committee).

Regardless, the FAA hasn't automatically accepted every single LSA rule as decided by the committee. There has also been negotiations for different rule changes over the years.

To say that the FAA didn't invoke that rule may be true in one sense, but that doesn't mean they wouldn't have pushed for it if it wasn't in the initial draft.

I don't see how it matters what the origin of the rule is.... the rule exists and it will do nothing good for the majority if a few try and figure out a way to beat the system (with this rule or any of the others that apply to LSA)
 
I started the thread with the application being a short home airstrip and wanting to be pitched for climb at the start of an x-c. It wasn't to go faster.

And also noted the oil-door switch access, or placard warning, and even "pocket remote control." Or hidden switch. You'd never get caught unless you have an accident, then your insurance might be voided, etc...

These responses have clarified the issue, EXCEPT FOR THIS:
1) What would be a suitable prop? Does one even exist?
2) What would be the maximum cruise speed on the -12 (Rotax) with an adjustable prop? I am thinking around 128. I get 122 with wheel pants and under gross.
 
I sympathize with the desire to experiment, but that's what EAB is for. I engaged in an ELSA build with my eyes open accepting the limits in exchange for the driver license medical, 5 hour test period and no 51% rule. I applaud efforts to expand the ELSA limits, but I made my bed so I have no regrets!
 
Now that I have some experience with the Rotax 912. I might try another build as a EAB RV12 then I would try this Unit.
http://www.airmasterpropellers.com/products/productdescription/type/view/id/19/ap420-system-overview

They are usually at OSH and I have talked to them a few times. They know the Rotax well and it seems like a great product.:)
Imagine a higher RPM producing a higher HP output in the Climb. This may make it easier to climb to cool air in the summer months. You would easily see 1200FPM climbs in cool weather. Then as you accelerate and reach 5500 RPM with a flip of a switch to Cruise setting pick up a quick 5 or 7 knots. Or you could try some glides with the prop feathered, that would be fun. Of course I would stay within the limitations of the POH. It would be fun to try it out for a while and if it didn't work very well I could always go back to the Fixed Pitched prop.
 
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Jetguy said:
Now that I have some experience with the Rotax 912. I might try another build as a EAB RV12 then I would try this Unit.
http://www.airmasterpropellers.com/products/productdescription/type/view/id/19/ap420-system-overview

They are usually at OSH and I have talked to them a few times. They know the Rotax well and it seems like a great product.:)
Imagine a higher RPM producing a higher HP output in the Climb. This may make it easier to climb to cool air in the summer months. You would easily see 1200FPM climbs in cool weather. Then as you accelerate and reach 5500 RPM with a flip of a switch to Cruise setting pick up a quick 5 or 7 knots. Or you could try some glides with the prop feathered, that would be fun. Of course I would stay within the limitations of the POH. It would be fun to try it out for a while and if it didn't work very well I could always go back to the Fixed Pitched prop.
Click to expand...
That's awesome
 
Jetguy said:
Now that I have some experience with the Rotax 912. I might try another build as a EAB RV12 then I would try this Unit.
http://www.airmasterpropellers.com/products/productdescription/type/view/id/19/ap420-system-overview

They are usually at OSH and I have talked to them a few times. They know the Rotax well and it seems like a great product.:)
Imagine a higher RPM producing a higher HP output in the Climb. This may make it easier to climb to cool air in the summer months. You would easily see 1200FPM climbs in cool weather. Then as you accelerate and reach 5500 RPM with a flip of a switch to Cruise setting pick up a quick 5 or 7 knots. Or you could try some glides with the prop feathered, that would be fun. Of course I would stay within the limitations of the POH. It would be fun to try it out for a while and if it didn't work very well I could always go back to the Fixed Pitched prop.
Click to expand...

I am thinking in the same light....that looks very interesting. Remove battery from fwf (just about removes weight penalty of prop); use lifi battery behind baggage bulkhead. Pick up low time 912 engine for much less$$$. Something to ponder🤓
 
I have a friend that says the following:

"At one time, I did a series of flight tests,
running the stock Sensenich at various settings from Low to High pitch stop.
The difference in performance was mind boggling.

At Low pitch, the airplane literally jumped off the field and climbed
like a banshee. But then at max rpm in cruise, I could only get to 89
kts. At the High pitch end, it took forever to takeoff, but cruised way
up in the 120s."

This sounds worth doing.
 
Airmaster constant speed propeller

The 3 blade Airmaster propeller fitted with whirlwind blades works very well on the Rv12. Exceptional takeoff performance, excellent climb at max gross and high density altitudes and heat. 3 preset rpm configurations (adjustable with the Airmaster software if need be) take off rpm 5,700 RPM, 5,400 RPM Climb 5,000 RPM Cruise and fairly consistent 18 ltrs / hr @ 25" manifold pressure.
 
AJSWA said:
The 3 blade Airmaster propeller fitted with whirlwind blades works very well on the Rv12. Exceptional takeoff performance, excellent climb at max gross and high density altitudes and heat. 3 preset rpm configurations (adjustable with the Airmaster software if need be) take off rpm 5,700 RPM, 5,400 RPM Climb 5,000 RPM Cruise and fairly consistent 18 ltrs / hr @ 25" manifold pressure.
Click to expand...

Andrew

What is the cruise speed?
 
3 blade Airmaster propeller / whirlwind blades

Re cruise speed- depends on throttle setting 😉 At 5,600 Da 25"Map 5,000 RPM 115 kts indicated 125kts TAS. 17-18 ltrs/hr.
 
catto 3 blade-RV-12

Has anybody seem real world info on Catto's new 3 blade fixed pitch for the RV-12???
 
Ivo

I flew a GA IVOProp on my 912 KitFox, and would consider it again. Adjusting was very easy: all blades move at the same time. The same technique is used to pitch the blades in flight (electricly). This feature is even retrofit for sale on existing props. Taking on account that these props by far are around the cheapest of the market (at that time, anyway), and story behind Ivo (this guy fled out of the iron curtain with a hang glider and a self-made prop), and you will understand that I at least consider flying one again.
 
Airmaster propeller

The Airmaster 3 blade propeller fitted with whirlwind blades works very well on the Rv 12. Exceptional take off and climb performance. 5,700 RPM on takeoff setting, 5,400 RPM climb and 5,000 RPM cruise. Top end cruise speed is pretty good also considering you have the best of T/O, climb and cruise even at max gross take off.
 
How about some real world numbers?;)
Let's use a cruise altitude of 8000feet.
At max takeoff weight, at 85F, at sea level, climbing at Vy 75 kts IAS.
What is your a average climb Rate to cruise in Feet per minute?
At what altitude do you switch from Take off mode to climb mode on the prop?
Assuming your OAT at 8000 feet is 60F what is you max indicated airspeed in smooth air at cruise?
What is your empty weight, CG, and moment with the prop installed and did you move anything from the original factory plans to balance the extra weight of the prop?
What is the weight of the prop in pounds?
Where did you mount your pitot tube and what pitot tube kit did you use?
When climbing to altitude at Vy when the OAT at takeoff is 95F, have you noticed high oil temps above 230F?

Thanks for the answers.:)

If anybody can think of any other questions now's your chance.:D
 
Evidently in-flight adjustable-pitch props are allowed in Australia.
In the USA, an aircraft registered as E-LSA can NOT be re-registered as an E-AB. And vice-versa.
 
Mich48041 said:
Evidently in-flight adjustable-pitch props are allowed in Australia.
Click to expand...

Correct. Our LSA rules just say you need a non-turbine engine fitted with a prop. We don't have a 120 kt speed limit either.
 
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Piper J3 said:
John -

LSA are not allowed to have in-flight controllable pitch prop. If you installed such a prop would RV-12 need to be re-registered as EAB?
Click to expand...

True, but if you build one as an EAB you can put one of these props on. This is a chance to have a discussion with a pilot who can give real time data if someone would like to peruse this at a later time.;) With the changes in the medical rules coming in the future this maybe an option for some builders. This prop could significantly improve the performance of a RV12 without a compromise in safety. I await the the numbers requested to see how well it performs.:)
 
Jetguy said:
True, but if you build one as an EAB you can put one of these props on. This is a chance to have a discussion with a pilot who can give real time data if someone would like to peruse this at a later time.;) With the changes in the medical rules coming in the future this maybe an option for some builders. This prop could significantly improve the performance of a RV12 without a compromise in safety. I await the the numbers requested to see how well it performs.:)
Click to expand...

Just to clarify an important point of this discussion....

Certification of pilots and airplanes are two totally different things.

An RV-12 that is already certified as an E-LSA can never have a controllable propeller installed, and still be legal to fly. There is no pathway for it to be re-certified into a category that would allow it (at least not a category that anyone would want).

You could do it by going E-AB when originally certified, but the airplane will always be stuck as an E-AB that can not be flown by a Sport Pilot. Even if the prop were changed back to fixed pitch (The rules state that for an airplane to be Sport Pilot eligible, it has to have met all of the LSA requirements for its entire operational life.)
 
AJSWA said:
The Airmaster 3 blade propeller fitted with whirlwind blades works very well on the Rv 12. Exceptional take off and climb performance. 5,700 RPM on takeoff setting, 5,400 RPM climb and 5,000 RPM cruise. Top end cruise speed is pretty good also considering you have the best of T/O, climb and cruise even at max gross take off.
Click to expand...
Okay.
Give us some numbers . . . gross weight . . . indicated airspeed (knots)/rate of climb . . . indicated airspeed and RPM at what density altitudes?

At your normal cruise altitude, what is your RPM at wide open throttle?
 
Airmaster propeller, with whirlwind blades.

Driftdown said:
Okay.
Give us some numbers . . . gross weight . . . indicated airspeed (knots)/rate of climb . . . indicated airspeed and RPM at what density altitudes?

At your normal cruise altitude, what is your RPM at wide open throttle?
Click to expand...

Will do this for you in 2 weeks time when I return home. Away on family matters presently. Sorry for the delay.
 
Airmaster propeller

Jetguy said:
How about some real world numbers?;)

If anybody can think of any other questions now's your chance.:D
Click to expand...

Aircraft is in primer coat only, not painted as yet so finish is not as smooth as a painted surface. Wheel spats and intersection fairings fitted.
At Max Gross T/O weight of 600KG (Actually 602.5kg, my passenger was heavier than he first admitted to)
Airfield elevation 1406' temp 15Deg C (Density Alt 1821')
13 minutes from 1406' to 8,000' average climb speed 83 knts and total climb average rate = 507 FPM (DA @ 8,000' was 9,123')
Climb was at 80 kts until around 5,500' oil temp reached 110degC speed was increased to 90 kts to cool off and complete the climb to 8,000'
Propeller remained in climb setting of 5470 RPM for the total climb.

At what altitude do you switch from Take off mode to climb mode on the prop?

Normally i fly mostly by myself or with lighter passengers and i mostly only use the "climb setting" off our sealed runway. You do need to pay close attention to the RPM when using the "T/O" setting with the RV12 as the engine will exceed max RPM if you allow the airspeed to exceed approx 70kts. It's a very steep and comfortable climb angle if you leave it in T/O and keep the speed below 70 Kts. (in T/O mode the engine is governed to 5,700RPM which is max power for Max 5 min RPM) Off a grass runway or at Max gross would be different, best to change from "T/O" mode to "Climb" mode pretty much immediately after lift off to prevent engine & propeller overspeed.

Assuming your OAT at 8000 feet is 60F what is you max indicated airspeed in smooth air at cruise?

Today at max gross weight @8,000' indicated (9,123'DA & 8 deg C) i was surprised to see the speeds lower than i expected. (I normally don't operate anywhere near Max Gross weight.)
WOT propeller in "cruise setting" level speed indicated 102 Kts TAS of 116Ks
Max engine RPM in propeller "cruise setting" mode is 5,050 RPM

What is your empty weight, CG, and moment with the prop installed and did you move anything from the original factory plans to balance the extra weight of the prop?

Yes, i relocated the battery and master relay to behind the baggage bulkhead LHS. (No other additional weight other than power cables etc added. I have my baggage placarded at 13 KG Max and this keeps the CG within the range with all combinations of loading Fwd and Aft including minimum fuel and pilot only. Once painted i may have to revisit as it may end up to close to the rear most limit fully loaded.

What is the weight of the prop in pounds? = 26lbs. :eek:

Where did you mount your pitot tube and what pitot tube kit did you use?

Pitot tube is mounted in the stall warner access cover plate in the Port wing.
Kit? A home grown special just a piece of 1/4 ally buddy tube shaped fitted with flare fitting to allow easy replacement if accidentally damage. (I tried the top of the fin location first out of interest which worked great in normal flying conditions, until near the stall speed where it would increase in speed up to nearly 80 Kts indicated at the stall break,i'm assuming the high speed air is from the propeller slipstream when in a power on stall attitude)

When climbing to altitude at Vy when the OAT at takeoff is 95F, have you noticed high oil temps above 230F?

Normally no higher than other RV12 people who have moved their oil cooler forward. I got to fly along side a friends RV12 a few weeks back and comparing our temps we were with pretty much 1 degree in oil and coolant temps. (He had also carried out the same oil cooler modification.)
In the summer months we have temps up to 50 DegC, so i only fly early morn and at higher climb speeds usually around 90kts to decrease the engine heat load and temperatures as much as possible, plus it's too uncomfortable getting bashed around by the thermals in these temps. (I know the 12 is a strong aircraft after flying off the first 25 hours heading into the summer of that year. You know it's going to be a rough ride when you can see dust devils (Thermals) rising up along your track.)

Unfortunately the photo's didn't remain in the correct sequence when i uploaded them, but if you look at the UTC clock time at the top of the screen in each, you can work out the climb and decent times and confirm the figures above.
Below is a Link to the screen captures and also the photos of the modifications, propeller install etc in other albums you should also be able to access.

https://flic.kr/s/aHskHwsu5S


Thanks for the answers.:) My pleasure.
 
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