Tim Jodice Posted August 28, 2020 Author Report Posted August 28, 2020 3 hours ago, Niko182 said: The increased climb and shorter takeoff roll are the smaller benefits in my opinion. The decreased noise, and the increased smoothness are the real selling points. at the end of the day a 1 to 2 knot cruise difference, an increase of 100fpm and and a decrease in a couple hundred feet only makes a 5 difference on a thousand NM trip. The real change is when the plane is turbine smooth and significantly quieter. You get to your destination feeling a lot more awake and less fatigued. This is spot on and is why I bought it. You need to experience it to believe it. @FoxMike did a nice write up on his Bravo. I talked to him and his first hand experience was a big factor in me buying it. I am thinking if he got a nice improvement already having an inherently smoother six cylinder spinning a 3 blade it would be BIG difference on a not as smooth 4 cylinder. In my opinion it did. If i buy another airplane in the future it would be the first thing on my list of improvements. Quote
Tim Jodice Posted August 28, 2020 Author Report Posted August 28, 2020 1 hour ago, ArtVandelay said: Did you measure the noise levels before and after? I intend to. I did record it before with the old prop. 1 Quote
Steve Dawson Posted August 30, 2020 Report Posted August 30, 2020 Thanks Tim for all your information including the price. If I was to keep my 201 I'd consider this option just for the noise factor alone. Can you update us when you get your noise results? Steve Quote
Guest Posted August 30, 2020 Report Posted August 30, 2020 10 hours ago, Steve Dawson said: Thanks Tim for all your information including the price. If I was to keep my 201 I'd consider this option just for the noise factor alone. Can you update us when you get your noise results? Steve Steve, Is your J for sale? I’ve got a client looking for one, he just did a PPI that didn’t go well. Clarence Quote
Steve Dawson Posted August 31, 2020 Report Posted August 31, 2020 Yes, I was going to list it In a couple weeks Clarence Email me if you need further info. Steve Quote
Guest Posted August 31, 2020 Report Posted August 31, 2020 7 hours ago, Steve Dawson said: Yes, I was going to list it In a couple weeks Clarence Email me if you need further info. Steve I will pass on your email address to him. Quote
JimB Posted September 1, 2020 Report Posted September 1, 2020 On 8/28/2020 at 6:14 AM, Tim Jodice said: This is spot on and is why I bought it. You need to experience it to believe it. @FoxMike did a nice write up on his Bravo. I talked to him and his first hand experience was a big factor in me buying it. I am thinking if he got a nice improvement already having an inherently smoother six cylinder spinning a 3 blade it would be BIG difference on a not as smooth 4 cylinder. In my opinion it did. If i buy another airplane in the future it would be the first thing on my list of improvements. That's why I want one for my F. I also get the added benefit of terminating an AD and get rid of my red arc RPM restriction. Quote
Tim Jodice Posted September 1, 2020 Author Report Posted September 1, 2020 56 minutes ago, JimB said: That's why I want one for my F. I also get the added benefit of terminating an AD and get rid of my red arc RPM restriction. Do you mean the AD on the hub? When was the last time it was overhauled? Quote
JimB Posted September 1, 2020 Report Posted September 1, 2020 1 hour ago, Tim Jodice said: Do you mean the AD on the hub? When was the last time it was overhauled? Tim, Not sure what you mean. The prop was overhauled sometime ago. The hub inspection was done about 40 hours ago. My understanding is the only way to get rid of the AD is upgrade the hub and if I'm going to do that, I will just replace the prop. Just overhauling the prop doesn't alleviate the AD unless I am missing something. Quote
Tim Jodice Posted September 1, 2020 Author Report Posted September 1, 2020 29 minutes ago, JimB said: Tim, Not sure what you mean. The prop was overhauled sometime ago. The hub inspection was done about 40 hours ago. My understanding is the only way to get rid of the AD is upgrade the hub and if I'm going to do that, I will just replace the prop. Just overhauling the prop doesn't alleviate the AD unless I am missing something. That is the hub AD I was referring to. If I recall there are two ways to deal with the AD. 1 eddy current test every 100 hours or a new B hub. Assuming the blades pass you are still half way to a new prop with a new hub and overhaul. If it has been a long time since overhaul it is likely the blades won't pass because of corrosion. I think a new propeller definitely makes sense for you. I got a quote from New England Propeller for a new Hartzell scimitar 2 blade of $10,400. The MT IS $12,200 without TKS. Even before owning one it was a no brainer to me. 1 Quote
bradp Posted September 1, 2020 Report Posted September 1, 2020 On 8/26/2020 at 3:06 PM, Yetti said: Because you were inverted. Did you flip him the bird ? 1 2 Quote
Tim Jodice Posted September 17, 2020 Author Report Posted September 17, 2020 I did a GPS run yesterday and confirmed that the propeller does not reduce cruise speed. It actually came out to be 2 knots faster but i was about 100 pounds lighter than last time so it is probably a wash. The part that I found amazing is glide range. Based off foreflight 11:1 and with it factoring wind it is about 30% better. Crazy right? With the prop pulled all the way out with the original 2 blade it would slow down to about 1400-1500 at 90 IAS. The MT slows down to 600-700 at 90 IAS. I would have thought that a 3 blade would make it worse. My thought is simply the fact that it allows the engine to spin slower so it makes less drag. What do you think? Quote
aviatoreb Posted September 17, 2020 Report Posted September 17, 2020 13 minutes ago, Tim Jodice said: I did a GPS run yesterday and confirmed that the propeller does not reduce cruise speed. It actually came out to be 2 knots faster but i was about 100 pounds lighter than last time so it is probably a wash. The part that I found amazing is glide range. Based off foreflight 11:1 and with it factoring wind it is about 30% better. Crazy right? With the prop pulled all the way out with the original 2 blade it would slow down to about 1400-1500 at 90 IAS. The MT slows down to 600-700 at 90 IAS. I would have thought that a 3 blade would make it worse. My thought is simply the fact that it allows the engine to spin slower so it makes less drag. What do you think? This is with engine at idle right - not shut off or wind milling shut off? I assume you had it at idle and maybe the lighter prop is easier for the low hp of an idling engine to turn? Maybe its a more aero prop? I never did proper glide tests of my former 3 blade vs my current 4 blade and I am not sure how I would get really representative glide range useful for an engine out emergency. I know a lot has been said but I can't remember the outcome - what is the glide range measurements of an engine at idle vs actually shut off and windmilling vs shut off and stopped? (Question not just for you but for the collective MS brain trust). Quote
Tim Jodice Posted September 17, 2020 Author Report Posted September 17, 2020 52 minutes ago, aviatoreb said: This is with engine at idle right - not shut off or wind milling shut off? I assume you had it at idle and maybe the lighter prop is easier for the low hp of an idling engine to turn? Maybe its a more aero prop? I never did proper glide tests of my former 3 blade vs my current 4 blade and I am not sure how I would get really representative glide range useful for an engine out emergency. I know a lot has been said but I can't remember the outcome - what is the glide range measurements of an engine at idle vs actually shut off and windmilling vs shut off and stopped? (Question not just for you but for the collective MS brain trust). This is with the throttle wide open, mixture cutoff and prop all the way out. Using the mixture is the only (without loading your exhaust system with fuel) way you can go from power to absolutely no power and back again instantly. In my experience with the original propeller the difference between idling and with the mixture pulled wasn't much different. With the MT it is still making power until you pull the mixture. My guess is it is because if idle is set at 600 and the prop can slow it down to 600 it will be making a little power. With the original prop there was a noticeable difference in drag between a windmilling and a stopped prop. Stopping a 2 blade was hard and wasted altitude doing it but it did glide better with it stopped. I haven't tried to stop the 3 blade. 2 Quote
flyer338 Posted September 17, 2020 Report Posted September 17, 2020 I was never able to get the Hartzell prop on my C-model to stop. I made the attempt at 12,500’. I wonder if the result might have been different at lower altitude in denser air? I closed the throttle while measuring glide ratio in order to lower cylinder pressure and allow the prop to turn more easily and thereby reduce drag. This thread has me seriously considering a MT prop for my J. 1 Quote
carusoam Posted September 18, 2020 Report Posted September 18, 2020 To get the prop to stop... Consider what it takes... 1) Air speed is a huge driving force to keep it turning... 2) prop control, pulled all the way out helps... Just by slowing the rotations as much as possible... 3) fuel mixture off, otherwise fuel will be sent (Unburned) to the exhaust system for later ignition... Boom, out go the muffler parts... 4) Throttle open or closed, probably won’t have as much of a noticeable affect... compressing more air or less air? As it uncompresses/expands equally with each stroke... When the prop is turning slowly enough, the throttle has very little effect on adding resistance to internal airflow... 5) the reason stopping the prop, when the engine goes out, is a high altitude option, for the most part.... the altitude lost caused by slowing down enough, is mostly wasted, and won’t be gained back, unless the lessened drag...can be used for long enough period of time... 6) If you are high enough... slow down to about landing speed.... or less... stay above stall speed... Wait for the rotational momentum to die out... It will take a balance of forces to slow the prop down enough... similar to an ordinary shut-down... 7) Essentially, you are trying to get the airfoil of the prop to stall... 8) once stopped, the compression of one cylinder is the only thing to keep it from starting to move again... 9) The light weight MT probably has very little rotational momentum compared to the heavier aluminum props... This list could be faulty... I didn’t check it recently... PP thoughts only not a CFI... Best regards, -a- Quote
philiplane Posted September 18, 2020 Report Posted September 18, 2020 On 8/28/2020 at 12:57 AM, flyer338 said: My take away from this thread is that a composite three-blade propeller on a J model, with no change to cruise speed, offers 16 lbs of useful load, along with a shorter takeoff roll and better climb. How much does this miracle cost? A bit more than $12k, so it is not an inexpensive miracle. 1 Quote
ArtVandelay Posted September 18, 2020 Report Posted September 18, 2020 A bit more than $12k, so it is not an inexpensive miracle.But if you have to buy a new prop anyway...this is the way I would go.Tom 1 Quote
Tim Jodice Posted September 18, 2020 Author Report Posted September 18, 2020 45 minutes ago, ArtVandelay said: But if you want to buy a new prop anyway...this is the way I would go. Tom My original propeller was overhauled in 17 and had about 450 hours on it. I was talking to a friend that owns a 201 that needed a new propeller. I sold mine to him. After reading and talking to people that own a MT propeller I wanted one. What he offered me i couldn't refuse so that is what made me buy it. I have be a mechanic of some sort since I was 16, I love things that have something to with making what ever vehicle it is better. Some people feel the same about a set of GTN750s. I am reminded how awesome this propeller is every time I push the throttle forward for taking off. Lastly I get to reset the maintenance clock on one of the most important parts of an airplane. Anyone in the area that want to fly behind it your welcome to come flying. 2 Quote
Tim Jodice Posted September 18, 2020 Author Report Posted September 18, 2020 14 hours ago, carusoam said: My experience: To get the prop to stop... Consider what it takes... 1) Air speed is a huge driving force to keep it turning... Biggest factor 2) prop control, pulled all the way out helps... Just by slowing the rotations as much as possible... Followed by pushing it back in to stall the propeller when you are going as slow as possible. 3) fuel mixture off, otherwise fuel will be sent (Unburned) to the exhaust system for later ignition... Boom, out go the muffler parts... Mixture only for shutting it down 4) Throttle open or closed, probably won’t have as much of a noticeable affect... compressing more air or less air? As it uncompresses/expands equally with each stroke... When the prop is turning slowly enough, the throttle has very little effect on adding resistance to internal airflow... Having the throttle closed makes it harder to spin the engine. 5) the reason stopping the prop, when the engine goes out, is a high altitude option, for the most part.... the altitude lost caused by slowing down enough, is mostly wasted, and won’t be gained back, unless the lessened drag...can be used for long enough period of time... Agreed, but I wouldn't do it. Especially now because of how slow the prop spins pulled all the way out. 6) If you are high enough... slow down to about landing speed.... or less... stay above stall speed... Wait for the rotational momentum to die out... It will take a balance of forces to slow the prop down enough... similar to an ordinary shut-down... You need to be at stall speed and hold it. I mean like stall horn on airplane shaking at stall. It took me multiple tries to do it. Slow down to fast and you stall the plane before the prop stops. 7) Essentially, you are trying to get the airfoil of the prop to stall... Agreed 8) once stopped, the compression of one cylinder is the only thing to keep it from starting to move again... Speeding backup to 90 IAS makes it lope over a compression stroke every 5 or so seconds. It takes about 140 IAS to air start the engine. 9) The light weight MT probably has very little rotational momentum compared to the heavier aluminum props... Alot less, when you shut off the engine it stops almost immediately. The prop saves weight and all of that weight savings are in the blades. When i was at the MT propeller shop i picked up a blade and was amazed how light it is. This list could be faulty... I didn’t check it recently... PP thoughts only not a CFI... Best regards, -a- 1 Quote
carusoam Posted September 18, 2020 Report Posted September 18, 2020 Great details added, Tim! Thanks for filling in my blanks... Best regards, -a- Quote
Tim Jodice Posted September 21, 2020 Author Report Posted September 21, 2020 I have 60 hours on the prop now and thought I would update how it is doing. It does help cooling a little. It took about a dozen flights to consistently see a lower temp so I knew it wasn't the variables like temp altitude weight etc. It really doesn't have a sweet spot RPM regarding vibration, spin it faster if you want to go faster. I have tried that from 2000-2700 I had the opportunity to fly through some rain and the pictures show that they have fixed the paint peeling issue. The rain was hard enough to take the boot adhesive off close to the hub but no problems at the tip. Like most say about Mooneys I want to go fast so unless I am below 5000 I almost always have it at 26-2700 RPM in cruise. I am still experimenting with coming down. When I am VFR I like trying to be efficient coming down so I try to time it so I come down at cruise IAS of about 140. With the 2 blade most lower (2200 down) RPM was not very smooth. I have found that 1800-2000 is a nice RPM for coming down. Quote
carusoam Posted September 22, 2020 Report Posted September 22, 2020 Let’s rotate the prop 90°... -a- Quote
flyer338 Posted September 23, 2020 Report Posted September 23, 2020 (edited) My Mooney is in the shop for an avionics upgrade - I am getting rid of the King HSI and AI in favor of an Aspen Evolution E5. I get to lose the remote boxes, lose the vacuum system, and keep the KAP-150. As soon as my wallet heals, I am going to think seriously about an MT prop. I wonder how much resale value there is in my McCauley? That might make a huge difference in when I do this. And three-blade props look cool. I will collect some climb, cruise, and noise data, before and after to share. I suspect the lighter propeller moving the CG aft might help with the cruise numbers. I think I will measure the cruise at 6,500 and 13,500. The EIS-4100 helps a lot (I think) between 11,500 and 13,500. Edited January 10, 2021 by flyer338 Typo Quote
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