Robert C. Posted November 4, 2021 Report Posted November 4, 2021 Actually, 2 of the 4 aren't visible. My O3 now also sports the Landing Height System and the Surefly Ignition. The MT 4-bladed prop is noticeably quieter and smoother than the old Top-Prop and it also adds a bit to runway acceleration. Some report greater deceleration when pushing the blue knob all the way in but I can't really tell the difference. And the 17 lbs increase in U/L is nice as well The Surefly EI does reduce fuel consumption by about .5 gph and easily runs deeper than 50 LOP if you're so inclined. I have not found it any easier to manage hot starts, but maybe that's faulty pilot technique. CHTs are higher with #5 now usually close to or over 400F under some conditions so I have to pay a bit more attention than before to engine temps. The VGs reduce stall speed by several knots and I'm now training myself to reduce approach speed to 75kts and cross the threshold at 65 kts or less. The (now recalibrated) AoA system that I got when I bought my Ovation in 2014 is a good help with that. The Surefly and VGs reduced my typical cruise performance from about 173 kts to about 169 kts so there is a bit of a speed penalty. The 4-bladed prop went on a few weeks later and doesn't seem to affect the cruising speed enough to be noticeable. Bottom line, MT Prop and VGs are certainly worth it if you value what they deliver. The LHS is a "nice to have" and the EI will pay for itself in the long run with lower maintenance and fuel costs but tbh it's not a game changer in any big way. Anyone needs a well maintained almost 600 hrs Hartzell Top-Prop? 4 Quote
Hank Posted November 4, 2021 Report Posted November 4, 2021 Looks nice! Hey, @Irmin, here's a used Top Prop available now! Quote
WaynePierce Posted November 4, 2021 Report Posted November 4, 2021 Just out of curiosity, do you have more ground clearance with the prop now than before? I was surprised to learn that there wasn't any difference in ground clearance with my 2 blade than a 3. Quote
Robert C. Posted November 4, 2021 Author Report Posted November 4, 2021 38 minutes ago, WaynePierce said: Just out of curiosity, do you have more ground clearance with the prop now than before? I was surprised to learn that there wasn't any difference in ground clearance with my 2 blade than a 3. Yep, 2 inches extra (74 vs 76). So a bit extra safety margin against prop strike. I don’t land on grass but have had to taxi on some rough grass parking patches that had me very worried so the extra clearance is definitely a benefit for me. Although you can get the 4 bladed also as a 76 inch prop. I asked about performance differences between the 74 and 76 MT props and they said there were no measurable differences. That said you’d think that with the 2 extra inches you’d get higher prop-tip speeds and hence more noise. 1 Quote
Ragsf15e Posted November 4, 2021 Report Posted November 4, 2021 3 hours ago, Robert C. said: Actually, 2 of the 4 aren't visible. My O3 now also sports the Landing Height System and the Surefly Ignition. The MT 4-bladed prop is noticeably quieter and smoother than the old Top-Prop and it also adds a bit to runway acceleration. Some report greater deceleration when pushing the blue knob all the way in but I can't really tell the difference. And the 17 lbs increase in U/L is nice as well The Surefly EI does reduce fuel consumption by about .5 gph and easily runs deeper than 50 LOP if you're so inclined. I have not found it any easier to manage hot starts, but maybe that's faulty pilot technique. CHTs are higher with #5 now usually close to or over 400F under some conditions so I have to pay a bit more attention than before to engine temps. The VGs reduce stall speed by several knots and I'm now training myself to reduce approach speed to 75kts and cross the threshold at 65 kts or less. The (now recalibrated) AoA system that I got when I bought my Ovation in 2014 is a good help with that. The Surefly and VGs reduced my typical cruise performance from about 173 kts to about 169 kts so there is a bit of a speed penalty. The 4-bladed prop went on a few weeks later and doesn't seem to affect the cruising speed enough to be noticeable. Bottom line, MT Prop and VGs are certainly worth it if you value what they deliver. The LHS is a "nice to have" and the EI will pay for itself in the long run with lower maintenance and fuel costs but tbh it's not a game changer in any big way. Anyone needs a well maintained almost 600 hrs Hartzell Top-Prop? Curious why you think the SF EIS slowed you down? Are you pulling back the MP to realize the fuel savings? Do you have the advance enabled? Mine is a couple knots faster with the SF running LOP. It’s the same speed as before ROP. Different engine though… Quote
Guest Posted November 4, 2021 Report Posted November 4, 2021 3 hours ago, Robert C. said: Yep, 2 inches extra (74 vs 76). So a bit extra safety margin against prop strike. I don’t land on grass but have had to taxi on some rough grass parking patches that had me very worried so the extra clearance is definitely a benefit for me. Although you can get the 4 bladed also as a 76 inch prop. I asked about performance differences between the 74 and 76 MT props and they said there were no measurable differences. That said you’d think that with the 2 extra inches you’d get higher prop-tip speeds and hence more noise. Wouldn’t it be 1” more tip clearance? Diameter versus radius? Clarence Quote
carusoam Posted November 5, 2021 Report Posted November 5, 2021 8 hours ago, Ragsf15e said: Curious why you think the SF EIS slowed you down? Are you pulling back the MP to realize the fuel savings? Do you have the advance enabled? Mine is a couple knots faster with the SF running LOP. It’s the same speed as before ROP. Different engine though… I think you may have mixed a point in there… wait for Robert’s reply… If I read this correctly…. Or I mixed a point… The slow things were the VGs and the fourth blade… The EI was a cause of extra heat… as more fuel gets completely converted before exiting the cylinder… aka the improved efficiency… CHT#5 is the known hot spot for O’s IO550 installation… LHS + AOAi = great speed control and good flare height control for nice easy landings…. (Easy on the airframe….) Super cool pirep Robert! (Electronic ignition for an IO550, VGs, LHS and the MT) One question… did you get the MT dynamically balanced after install? (Just wondering) Best regards, -a- Note for Imin… Check to see if the TopProp above can be used on a Lycoming IO360…. It is coming off a Continental IO550… Quote
carusoam Posted November 5, 2021 Report Posted November 5, 2021 With all of those fancy upgrades…. Can you get the plane off the ground in less than 800’ Pick a chilly day, and a good headwind, a very light GTOW… and use CloudAhoy to measure the T/O run… O3 Acceleration is a blast… EI may add a touch of power… The four blades are great for pulling from 0 to Vne… at max power… VGs decrease the speed needed to generate max lift… Using a soft field style to get into ground effect early… Practice probably will improve the results…. The lower sound level of the MT will be neighbor friendly enough you might get a few tries in the same flight without a noise complaint… PP thinking out loud… not a CFI… Best regards, -a- Quote
Ragsf15e Posted November 5, 2021 Report Posted November 5, 2021 10 minutes ago, carusoam said: I think you may have mixed a point in there… wait for Robert’s reply… If I read this correctly…. Or I mixed a point… The slow things were the VGs and the fourth blade… The EI was a cause of extra heat… as more fuel gets completely converted before exiting the cylinder… aka the improved efficiency… CHT#5 is the known hot spot for O’s IO550 installation… LHS + AOAi = great speed control and good flare height control for nice easy landings…. (Easy on the airframe….) Super cool pirep Robert! (Electronic ignition for an IO550, VGs, LHS and the MT) One question… did you get the MT dynamically balanced after install? (Just wondering) Best regards, -a- Note for Imin… Check to see if the TopProp above can be used on a Lycoming IO360…. It is coming off a Continental IO550… Maybe, but this is what I was referring to: ”The Surefly and VGs reduced my typical cruise performance from about 173 kts to about 169 kts so there is a bit of a speed penalty.” 1 Quote
Robert C. Posted November 5, 2021 Author Report Posted November 5, 2021 19 hours ago, M20Doc said: Wouldn’t it be 1” more tip clearance? Diameter versus radius? Clarence Yep, you are correct - my bad (brainfart) Quote
Robert C. Posted November 5, 2021 Author Report Posted November 5, 2021 21 hours ago, Ragsf15e said: Curious why you think the SF EIS slowed you down? Are you pulling back the MP to realize the fuel savings? Do you have the advance enabled? Mine is a couple knots faster with the SF running LOP. It’s the same speed as before ROP. Different engine though… Yeah, I now realize that I contradicted myself a bit in the original post. The VGs and the Surefly were done at the same time (about a month before I got the new prop) so I can't prove which contributed what to the modest speed reduction. The VGs I can understand, but you'd think the EI wouldn't impact true airspeed. 1 Quote
Robert C. Posted November 5, 2021 Author Report Posted November 5, 2021 Anthony, @carusoam Thanks for the observations and questions. No, I did not have the prop dynamically rebalanced. My AP didn't think it'd be necessary and the way it flies doesn't give me the feeling that it needs to be. What would be good indicators that I should get them to rebalance it? Robert Quote
Irmin Posted November 9, 2021 Report Posted November 9, 2021 On 11/4/2021 at 6:16 PM, Hank said: Looks nice! Hey, @Irmin, here's a used Top Prop available now! Thanks for the effort, but I am looking for a propeller for the J-Model Quote
Will.iam Posted November 9, 2021 Report Posted November 9, 2021 On 11/5/2021 at 12:29 PM, Robert C. said: Yeah, I now realize that I contradicted myself a bit in the original post. The VGs and the Surefly were done at the same time (about a month before I got the new prop) so I can't prove which contributed what to the modest speed reduction. The VGs I can understand, but you'd think the EI wouldn't impact true airspeed. My surefly increased my speed at same fuel flow or gives me the same speed on .5 gph less when operating LOP. Quote
StevenL757 Posted November 9, 2021 Report Posted November 9, 2021 On 11/5/2021 at 1:43 PM, Robert C. said: Anthony, @carusoam Thanks for the observations and questions. No, I did not have the prop dynamically rebalanced. My AP didn't think it'd be necessary and the way it flies doesn't give me the feeling that it needs to be. What would be good indicators that I should get them to rebalance it? Robert Mainly, noting any vibration that wasn’t there prior to the prop switch. I’d have to respectfully disagree with your mechanic about a dynamic balance being necessary. I’ve done four of them, and you never know how much improvement could be gained until you get the machine hooked up, do the necessary run-ups, and look at the data. Quote
201Mooniac Posted November 10, 2021 Report Posted November 10, 2021 When I added the 3 blade MT prop to my M20J I had the balance checked and it was as close to perfect as the balance guy thought he could get it so nothing was needed. I agree though it should be checked even if it feels smooth. Quote
Robert C. Posted November 10, 2021 Author Report Posted November 10, 2021 Thanks guys. I'll ask him to do it at the Annual in February. Always learning new things on MS Robert Quote
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