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View Full Version : Would like Info On IFA IVOPROP



kmach
08-22-2011, 05:21 AM
HI All,
I have a newly mounted , ground adjustable Medium IVO RH 3 blade 70" on my 912ULS , I am thinking of converting to the inflight.

I am looking for input. Any stories on the conversion , tips , hints would be appreciated.

Any regrets , or problems with the inflight (failures).

I have only flown 3 hrs with the GA and can see it's possibilities, and now am really thinking about the inflight adjustable possibilities !!:)

I would like to make up my mind before I start messing with spinners !

Slyfox
08-22-2011, 07:30 AM
the only advice I have is, just do it. Get the through hub wiring. converts from the brushes on the outside of the spacers and wires everything through the center of the prop, thus the brushes will end up behind the gear box. This set up has worked very well for me for about 5 years now. Believe me, the inflight is the way to go, opens up many possibilities. You will dazel anybody that watches you fly or fly with you, airplane on your wing.

kitfox2009
08-22-2011, 08:47 AM
Hi Kevin

I see you are keeping up with aviation mantra of "keep throwing money at it until it REALLY works"!!!

Just throw a bit more and get the IFA kit. You won`t regret it.

Cheers

Don

Did you get that ugly hail storm last week? The pics said 35 mile north of Regina.

kmach
08-22-2011, 12:01 PM
Yep, no shortage of places to spend money!!

I am planning on giving you a call to pick your brain on the IFA.

That "hail" was on the south side of the valley, we got just rain on the

north side. Lucky for now !

Kevin

Slyfox
08-22-2011, 12:10 PM
I have caught my self clicking my heels together and saying" I will not spend money on my airplanes today, I will not spend money on my airplanes today, I will not spend money on my airplanes today". The only thing that happened, I woke up.

jtpitkin06
08-22-2011, 05:02 PM
I don't know the rules in Canada for certification, or if you fly the equivalent of Light Sport with your Outback. However, in the US if you put on a IFA prop, it knocks the aircraft out of Light Sport FOREVER... even if you go back to a fixed pitch prop. For some people, it's not important, but it is a factor to consider.

John Pitkin
Greenville, Texas

Slyfox
08-22-2011, 05:50 PM
I heard if you put a posting on the switch not to use inflight you're clear of that rule. At least that's the type of thing cub crafters is practicing.

kitfox2009
08-22-2011, 06:05 PM
Canada does not have a LSA classification. We have Basic Ultralight and Advanced Ultralight. Kevin`s a/c will be too heavy for either of these classifications and will be a Homebuilt. The operator must have a PPL or at the very least a Recreational Pilot`s License. IFA propellers are allowed.

Don

akflyer
08-22-2011, 08:38 PM
I don't know the rules in Canada for certification, or if you fly the equivalent of Light Sport with your Outback.

Yes, but first you have to be dumb enough to put the IFA in your log book... A simple entry of IVO Medium will do just fine.

jtpitkin06
08-22-2011, 08:45 PM
Don,

That makes things a lot simpler. If it is in your budget, I'd go for it. An IFA prop makes the aircraft a lot more flexible in performance with the benefit of noise reduction. Better climb and quieter cruise.

John

SkySteve
08-23-2011, 06:15 AM
Why not just install a Power Adjustable or Electronic Adjustable prop? Very similar to the IFA but designed for use by Sport Pilot certificate holders so they can easily adjust their props on the ground.

Their Private Pilot friends can also use it to adjust the prop in the air during flight. That way it's convenient for any pilot.

SkySteve
08-23-2011, 07:22 AM
Wow! Amazing! Well, I guess that makes it easy.

DanB
08-23-2011, 07:28 AM
I know of some pilots that wanted to register their plane as ELSA installed the IFA (electric adjustable) but put the switch under the cowling...still only a ground adjust, but much easier. Not so sure all DAR's would let it fly with a plackard next to the switch (not to be used in flight). Kinda like setting a candy jar in front of a kid with a sign that says do not eat. ;)

Slyfox
08-23-2011, 08:04 AM
totally agree, but there was a thread not to long ago that said cub crafters is place carding a bunch of stuff that isn't allowable for sport pilot in their new aircraft to be legal.

kitfox2009
08-23-2011, 08:41 AM
Hi Guys
I think the original post was asking about concerns and/or problems with the actual operation of an IFA prop. The discussion seems to have morphed into "how to circumvent regulations".

I know in the 70 or so hours I have had my IFA IVO I have had no issues at all. The first set of brushes seemed to wear down rather quickly. IVO explained that it takes a while for the commutator to "carbon up" and this is exactly what happened. Unless something drastic happens soon, there is no way I will ever go back to a fixed or GA propeller!

Have fun

Don

Slyfox
08-23-2011, 09:25 AM
you are so right Don, we did get off into left field here. As stated, my prop, the same exact one, medium 70" IVO with IFA is absolutely the best. I did have an issue of adjustment slow down. I thought I had a motor problem. I removed the engine cover and looked things over and found the brushes were a little off center, adjusted that(took a spacer to bring the brushes out a bit), after doing that my speed came back up on adjustment. Than I looked at everyting as a whole and found grease or oil on the brushes and area it rides on but found no leak. I took some brake cleaner and sprayed it nice and clean. I now have it working real nice again. I did order from IVO a new set of brushes for a spare but haven't put them on yet.

On my current prop I have over 200hrs of trouble free operation. I would not go back to a fix prop if you paid me, I absolutely love my adjustable prop. Can't emagine flying without it.

ahazi
08-23-2011, 09:30 AM
Any experience and/or concerns about the plastic parts in the IVO IFA prop? In one instance (last year during the Kitfox factory fly-in) there was an individual that his IFA IVO got stuck and he had to come back, disassemble the mechanism and replace some parts (motor, gear etc.)

Personally I love the concept as the airplane that I fly now (Diamond DA40) has a constant speed prop and it is a day and night difference compared to the same IO-360 engine w/o constant speed especially when it comes to not having to compromise on climb vs. cruise. I cruise at 10 - 12k feet at almost 140 KTS with a fuel flow of less than 7 GPH with 2 people and luggage.

During this year Oshkosh I specifically looked for alternatives to IVO IFA as I absolutely want IFA for my KF7 but wanted to see if there is something better. I met with the owner of Airmaster (http://airmasterpropellers.com/) from New Zealand and they have a much nicer (more mechanically elaborate but also seems more robust than IVO) solution that comes at a cost. They use Warpdrive prop blades and it is still electrically adjustable and it comes with a nice control box that makes it into a constant speed. I think IVO offers a similar add-on.

To me the electrically adjustable constant speed looks a bit like something with potentially limited life time. I also understand that there is a way to get a Rotax with a hydraulic constant speed add-on (never seen one). So from my point of view I would like to hear more along the lines of what kind of IFA props can be paired with a 912S engine and the pro and cons of each.

Ariel
Building KF7
Flying DA40
KSMO

Slyfox
08-23-2011, 09:42 AM
I remember with my patriot prop IVO, that there were some problems with the gears, I upgraded to their newer motor and didn't have any more problems. The medium prop has a much bigger motor, and it is good.

RandyL
08-23-2011, 10:56 AM
totally agree, but there was a thread not to long ago that said cub crafters is place carding a bunch of stuff that isn't allowable for sport pilot in their new aircraft to be legal.
We have a placard on the Carbon Cub SS instrument panel that lists altitudes/rpms that represent the "max continuous power" level, it has nothing to do with the prop which is not IFA. The Carbon Cub SS is fully LSA-compliant.

jrthomas
08-23-2011, 02:20 PM
If I might add my 2 cents worth, I'm the dummy who brought up "placecarding" the IFA switch to fudge a little on the technicalities. Maybe the Cub Crafters SS was a bad example but there a lots of very slick LSA's that obviously will exceed LSA speed limits and it seems to me placecarding for a max rpm would be the only way to keep the speeds down. I talked to the builder of a Sonex Wiex recently that was registered as an LSA. According to the builder it would exceed 200mph at altitude with throttle to spare. I know the regs state "138mph at sea level" but this takes fudging to a whole new level. Everybody fudges. That's why we have LSA. It's because everybody fudged. All those 400 pound, 582 powered ultralights helped get us Sport Pilot. Now we have 180hp light sport aircraft that are capable of 2000 pound gross but are limited to 1320. Now add 2-200 pound adults and anything more than 5 gallons gas will put it over max gross. I wonder if anyone will fudge a little. I like the idea of "No log entry". Then as the builder I can do my own annuals. James Thomas Kitfox IV Fixed pitch prop No Fudge-

RandyL
08-23-2011, 02:38 PM
I know the regs state "138mph at sea level"
Look a little deeper, it says that the 138 mph is CAS (calibrated air speed). What is the TAS (true air speed) when doing 138 CAS at 9,999' msl? Depending on the temperature gradient it's generally around 165 mph TAS and perferctly legal for an LSA.

The above has nothing to do with a prop, sorry for the thread creep, but thought you all would appreciate that clarification.

Slyfox
08-23-2011, 03:29 PM
sorry to come back in on this, but it's clear that placecarding does get you out of the hot seat with the FAA. Now what happens after the aircraft is certified,well it's all on what the owner of the aircraft puts in the log books and on the placecards. Ah what's that switch for, oh I don't know, why is it there, I don't know, must have forgotton to take it out. I guess it's used for nothing. That's if you let the FAA look at your airplane in the first plane, I don't think they can. Just saying, not that it's true mind you.

War Eagle
08-23-2011, 09:44 PM
I am going to take a stab at answering the question about other IFA props.

I am part of a group in Nampa that built 14 Series 7 KFs. Three of them with 914s, one with an 0-200 and ten of them with the 912s.

Seven of those KFs we installed the Airmaster CS props, three of them with the wood GSC prop and three with the Warp drive prop a one with a french made prop. Sorry I can't remember the name of it at the moment. No IVOs in any of them.

When we were looking at the various CS props we looked at Airmaster, Hoffman, NSI and one other that I can't remember the name of right now. This was all done back in 2003.

Skystar at the time had a series 7 that had a 914 with a Hoffman CS prop. This required the Rotax 914 to be ordered with the crankshaft and govenor for a CS prop so it could be controlled by hydraulic pressure.

The other CS props we looked at were all electric controlled.

None of us wanted to spend the extra money for the engine changes that would allow the use of a hydraulic controlled CS prop.

The Airmaster turned out to be the least expensive option at the time and it had an excellent reputation. Some of the other electric CS options didn't have as stellar reputation when we started talking to end users.

We went with the Airmaster and we are all extremely happy with the prop and it's performance. While a CS isn't everyone cup of tea (so to speak) they really increase the performance of the plane in very drastic manner when compared to a fixed pitch equipped 912s or 914.

In a not to often spoken about situation, we have out performed some of the local IVO IFA equipped 912s with one of our Airmaster equipped 912s. Of course the IVO IFA is not a CS but there are those that think there is nothing better when they have flown behind their IVO.

I am not trying to put down anyones choice of prop but the IVO IFA can't match the performance of an Airmaster CS prop even though there are some that think it is possible.

Some of these Airmasters have been flying in the series 7s for 8 years now.

The price today is much higher than when we bought ours a few years back (thanks to the weak US dollar) but these were an excellent investment and have been everything that we every wanted in performance.

Av8r3400
08-23-2011, 10:13 PM
Just be mindful of the weight limitations on the gearbox of a 912/914. Nickle inlaid, square tip Warp blades are very heavy.

A 3-blade, 72" diameter, square tip, nickle inlaid warp prop is too heavy and will void the warranty on a 912. Taper the tips (my prop) and it is JUST under the red-line on weight.

kitfox2009
08-24-2011, 06:31 AM
Hi All
Over the past number of years I have been able to visit friends and family in New Zealand and have got to know a number of folks in the "microlight" community there. What a great country for flying too!
Everyone that can afford to has switched to the Airmaster for their 912S and 914 engines.
From their experiences these props are definitely the ultimate unit that is currently available but are very expensive! I believe my IVO 70" IFA was about $1200 last year. I can handle that!
Cheers
Don

kmach
08-26-2011, 02:04 PM
the only advice I have is, just do it. Get the through hub wiring. converts from the brushes on the outside of the spacers and wires everything through the center of the prop, thus the brushes will end up behind the gear box. This set up has worked very well for me for about 5 years now. Believe me, the inflight is the way to go, opens up many possibilities. You will dazel anybody that watches you fly or fly with you, airplane on your wing.


Hi,
do you have any pictures of the behind the gearbox wiring setup ? How far does it protrude towards the firewall from the gearbox ? I have an oil cooler thermostat mounted in the area behind the gearbox.

Do you still use all the Ivo parts ?, like the slip rings and isolators that are required with there wiring setup. It seems that these could be omitted if a person was wiring thru the rotax hub.

I am considering the setup that Murle Williams sells.

Thanks; Kevin

kmach
08-26-2011, 02:09 PM
Hi All,

I ordered the IFA conversion kit today . That's enough thinking about it !;)

Now the question is constant speed adapter or not:rolleyes:

Slyfox
08-26-2011, 02:12 PM
that's what I have. I put a little bracket and mounted my oil thermostat on top of the gear box, one of the two top bolts. Than the setup for through the gearbox mounts right directly behind the gear box, the shaft that goes to the prop is hollow, fits in there and has a long bolt and nut that goes through all that, than two wires end up out the front and than your prop goes on. You can eleminate the extra spacers and insulators, but than you will need new prop bolts. I was in to much of a hury so I just sandwitch everything but threw the insulators and just put it on, sticks out front a bit but that doesn't hurt the operation.

I in turn put all my 360 degree markings on my spacers and that gets used for when I balance my prop. A rebalance currently is real quick for me for I leave the tape on the prop blade and the degrees on the spacers make it real nice.

Slyfox
08-26-2011, 02:24 PM
Hi All,

I ordered the IFA conversion kit today . That's enough thinking about it !;)

Now the question is constant speed adapter or not:rolleyes:

na, waste of money for the constant speed.

If you just throw the kit on you will be pretty flat, on take off you just adjust to 5800 rpm. (If I am playing with my prop on the ground I go flat all the way and course it for about 1 second, pretty much puts it good for take off). After you get going you can leave it at that(5800) for max take off, or adjust to 5200, I find 5300 offers just a little smoother operation.

going into land I pull back on the throttle(zero climb) and put the tach on 4400 rpm and than run up the prop(hit the switch), flater, to 5200 rpm(about a count to 3). this puts it automaticaly perfect for the next take off. I've thought of putting in the washers, but I don't like to work any more than I have to, so I haven't done it. Besides if you put it real flat and you watch your rpm, you won't believe the straight up and out you can get with your fox. Yes, I have gotten in trouble with the local FSDO seems they think I'm doing aerobatics. shhhhh don't let them know that's a normal thing for a kitfox.

One more thing, I would mount your toggle switch right next to the throttle, mine is in a hole to the left of my throttle, very easy to hit it with my index finger.

did I mention I love my setup.

kitfox2009
08-26-2011, 04:40 PM
Hi Kevin

The operation Slyfox describes is pretty much how I run mine. Just be careful you don`t "over-rev" when you are using the flatter pitch.
I have my switch just left of the throttle. Push LEFT for coarse. RIGHT for fine. Works easily with the index finger. I believe you will be pleasantly surprised just how sensitive this unit is. Small adjustments make a world of difference!
Have fun
Don

Slyfox
08-26-2011, 04:54 PM
not that it matters but I put mine up for fine and down for course.

kmach
08-27-2011, 08:02 AM
Good stuff ! I was planning on putting the switch left of my throttle, so you both have confirmed this idea.

Are you guys running spinners ?

I am going to call UHS next week. I don't think the UHS (9P) I have for the GA IVO is going to work with the IFA, the GA spinner mounts under the 3/8" prop bolt heads with a cutout for the jam nut.

I would like to set the prop up once, with the spinner and possibly some limitation washers, this might be hard to do but worth a try.

It's hard to plan without the hardware in your hands!

av8rps
09-21-2011, 08:17 PM
Here's something I shared on another forum recently when someone asked a similar question;

Last night while flying my Kitfox (on Aerocet amphib floats) in really nice calm skies I did a test to see what the real gain is for top speed using my IVO in flight adjustable prop verses if it were a ground adjustable version (to do the comparison I just moved the prop switch to change the pitch, "pretending" as if I had adjusted the prop on the ground with a wrench and a prop angle gauge).

Here are my results;

Flying straight and level with wide open throttle (912ul - all 81 ponies)

- At 5800 max rpm I was able to go 119 mph.

- Leaving the prop set for a max rpm of 5800, I pulled the throttle back to 5500 rpm (max continuous power for a 912) and my top speed was now 114 mph.

- Putting the throttle back to wide open again, I increased the pitch so I could only get 5500 rpm, which provided the highest speed tested...124 mph.

- Moving the electric prop to maximum pitch while keeping the throttle still wide open, giving me 5275 rpm my top speed dropped to 116 mph.

So, I proved to myself last night that the inflight adjustable prop does in fact make my Kitfox faster. BUT, if I set a ground adjustable version to a max of 5500 rpm, it would fly just as fast (assuming the blade style and dimensions were the same for both props). Of course, then I would lose some takeoff and climb performance, so a better setting for water ops or STOL work might be a max rpm setting of 5800 rpm straight and level. So I could expect to lose around 10 mph in top speed when comparing the IFA to a ground adjust version.

In addition to the improved top speed, takeoff, and climb, another thing I really like to do with mine is to fly around at 4,000 rpm at 80-85 mph with a lot of pitch. It makes for a really quiet and smooth pleasure flight that doesn't burn much fuel.

So for now, I'll be keeping my IFA prop. I shared this information so I could let everyone know what the real gains are with an IFA prop.

Dorsal
09-22-2011, 03:43 AM
Nice write up, confirms my thoughts on IFA. What surprises me most is that you manage to get 124 mph with 80 hp and floats, thats about what I get with a cruise pitched prop and a 912S. Very impressive as I had thought floats would have significantly more impact on top speed.

SkyPirate
09-22-2011, 07:36 AM
Back in the 1900's ,..thinking 97,..might be off a year or so ,. I was playing with a set of flat bottom fiberglass floats,..that were rated for around 700 lbs ,.so I put them onto a 3/4 wing sprint,.. top speed prior to putting the floats on was 65 mph,.after I put the floats on my speed indicated 70 mph,..this is with a 447 fix pitch,.
the floats,..I cant remember the manufacturer ,..were round top flat bottom with a 2 1/2 " step,..the had a single top square tube mounting system that was mounted on top of the float from the step forward about 5',..I didnt like the way the floats,.."flopped" and twisted when taking off and landing so I added some braces on a 45 degree to the inside ,..or between each float,..so ,..my point ,.I had added even more to the drag of the orginal set up.
I didnt get too indept as to finding out why I gained speed with the floats,..I'm sure the added weight ,..but also the angle of the bottom of the floats in relation to flight had something to do with it,..

So ,..the shape of a set of floats? the angle of incedence in relation to flight? and the weight? and of course the drag of the system you choose to mount the floats,..evidently I got lucky in my set up because I was able to gain speed even though the drag was increased.
the flat bottom floats flew great ,..the problems with them ..flat water ,..you had to basically go out to where you wanted to seperate from the water and spin around a couple times,..back track down wind and then head towards the waves you had made to get seperation,..
and I did not land or take off in any swells over a foot,..the flat bottom floats will literally beat the crap out of you at speed
I would NOT recommend flat bottom floats for a kitfox or anything that hit's or leaves the water in excess of 40 mph

sorry for getting way off topic ,..just a little piece of float info

av8rps
09-22-2011, 03:31 PM
Nice write up, confirms my thoughts on IFA. What surprises me most is that you manage to get 124 mph with 80 hp and floats, thats about what I get with a cruise pitched prop and a 912S. Very impressive as I had thought floats would have significantly more impact on top speed.

Yeah, my little Ol' 80 hp Model IV is a real hotrod.:) It totally irritates my friends that fly LSA type seaplanes with me because they typically struggle with keeping up (Rans S7, Rans S6, Highlander, Zenair 701, etc). On average my top speed is 20 mph faster than those planes, and I am running an 80 hp 912 vs their 100 hp 912s's. But I also am running that IVO IFA when they are typically running Warp ground adjustables.

And yes, for anyone wondering...I have verified my airspeed accuracy. In fact I've done so countless times. It is accurate within 1-2 mph.

And for anyone thinking a Kitfox might be faster on floats than on wheels, it flies about 6-7 mph faster when on its regular gear with 8.00 - 6 tires. The Aerocet floats are pretty low drag for a float, but they still are 14 ft long, two plus feet around, use gobs of high drag bracing cables and attaching struts, and weigh more than 200 pounds. That all makes for a lot of added drag that my little ol' 80 hp Kitfox has to push (and lift) through the air. I marvel at the fact that it does so well with that, and consequently love the performance of my Kitfox amphib.

Oh yeah, I forgot to mention that with just me and 2 hours of fuel in near perfect conditions I can get my Kitfox off the water in 6 to 8 seconds, and 13-15 seconds with 400 lbs cabin load. If you know much about seaplanes, that is equally as amazing as my top speeds.

And while it is all pretty amazing, we really shouldn't be surprised that it can compete with the speed performance of a newer model Kitfox. The wings are the exact same for both airplanes, yet the newer Kitfox is likely to weigh on wheels what my Kitfox weighs on amphibs (776 lbs). So wing loading is the same. And then when you consider how much smaller in size the IV is than the newer Kitfox, I suppose it is possible that a Model IV on floats could have similar drag to the larger Kitfox on wheels, especially a nosewheel version without pants. Throw in the fact that I use an IFA IVO, and even though I only have 80 hp, it suddenly starts to make more sense. At least that's how I see it.

And honestly, I'm not completely sure why it flies like it does. But I sure do enjoy it! It is an awesome airplane, and is even more awesome as a seaplane. I couldn't be happier with it (but I admit that one day just for grins I may put that 100 hp 912 I have in it, just to see what it will do) :cool:.

(One last note I thought of as I was ending my novel)

I have now played with 3 different IVO props;

A UL 3 blade "High pitch" that was only 65" in diameter and wouldn't let me get the rpm any higher than 5100 rpm for takeoff with the electric IFA motor.

A 68" UL 3 blade that would allow the motor to flatten the pitch for takeoff to 5800+ rpm.

And a 72" 3 blade UL that will let the motor flatten the blade so I could get 5750-5800 rpm for takeoff.

Results;

The 65" diameter blade actually makes the airplane fly the fastest, but takeoff and climb performance suffered (due to being unable to get the blade flat enough to get max rpm, or the blade length, or both?)

The 68" blade is the best all around for takeoff, climb, and cruise, and is the prop I feel works best overall.

The 72" gives a much better takeoff and climb, and better braking on descent, but drops the top speed by about 6 mph.


What I believe I learned by playing around with these various props is that we are many times running too long of a prop on the smaller hp 912. A smaller diameter prop is likely to provide better overall performance.

And it's not just the IVO. If you read comments some of have made about KIEV's on the 80hp vs the 100hp 912, it appears they may have experienced the same thing?

But of course, this is all subject to testing accuracy. So take it for what it's worth...and remember that it didn't cost you anything. ;)

Slyfox
09-22-2011, 03:48 PM
I agree, when I had the 912ul I also had the Ivo and I found that going to the size you suggested gave me the best all around performance. IVO in my opinion can't be beat.

av8rps
09-22-2011, 03:56 PM
So I'm curious, on the 100 hp 912 does the 72" work better? I would think it might, but I don't have the 100 hp on my Kitfox to test. Although I have thought about taking the Sensenich off my Highlander and trying my 72" IVO on that as it has a 100 on it. But, comparing the Highlander and the Kitfox would really be an apples and oranges comparison.

av8rps
09-22-2011, 04:06 PM
Back in the 1900's ,..thinking 97,..might be off a year or so ,. I was playing with a set of flat bottom fiberglass floats,..that were rated for around 700 lbs ,.so I put them onto a 3/4 wing sprint,.. top speed prior to putting the floats on was 65 mph,.after I put the floats on my speed indicated 70 mph,..snip snip

Interesting information for sure. It is basically unheard of for any airplane to gain speed by adding floats. Traditionally the best you can hope for is to not lose any speed, but that is also rare. Early, very lightweight Avid Flyers were known for not losing speed with the addition of floats. But as the Avid Flyer's evolved, and got heavier, they too lost speed.

And I couldn't agree more with your comment about flat bottoms on floats. I also own a LA-4 Lake Amphibian, and it has a pretty flat hull compared to the later "Renegade" model. And let me tell you, rough water and boat wakes can be a real handful. There's nothing worse than not being up to flying speed and getting tossed into the air when you are in an airplane that can quickly develop an uncontrollable porposing condition. The deeper V they put on later Lakes solved that problem 99%. So even if a flying boat vs a float, flat bottoms are not the answer.

Slyfox
09-23-2011, 07:36 AM
I believe mine is a 70" medium. I had the patriot at first on it but would cavitate on take off If I put the power to it too much. I love the medium for the 100.