gsengle Posted January 31, 2019 Report Share Posted January 31, 2019 its a bit faster at altitude, as in maybe a knot or 2, but it does help a lot for the takeoff and climb. It might not be worth it for the regular ovations, but on the eagle it makes it a whole new aircraft. If i had to do it again I'd do it in a heartbeat. Makes the aircraft way more capable, compared to the eagle. I don't know the difference in feel between the 280 and 310hp engine. I do know the difference between the 244 and 310hp, and it it gigantic.[mention=8040]gsengle[/mention] I think you also need a knew Profile Pic. that McCauley is nothing compared to the Hartzell, appearance wise. Ok I’ll update it some time! Here is the present state of affairs....Sent from my iPhone using Tapatalk 3 Quote Link to comment Share on other sites More sharing options...
carusoam Posted January 31, 2019 Report Share Posted January 31, 2019 The brief discussion on hp and derating is one of the key points I wanted to hear from Bob Minnis... When you find out how much hp the IO550 can handle, 310 isn’t very much... Makes you want to go experimental to legally get some more... The difference between 280 and 310 hp is only about 10%... The T/O distance goes from 1200 to 800’ about 33% shorter... Seat of the pants acceleration is gigantic... Power to weight ratio beats Corvettes of the same vintage... If going from 244 to 310... That’s even more gigantic! The hard part would be getting the upgrade without needing it... That is a fair amount of dough to spend... If you experience a ground strike... you have something to look forward to... Best regards, -a- Quote Link to comment Share on other sites More sharing options...
carusoam Posted January 31, 2019 Report Share Posted January 31, 2019 GS, Your present state of affairs is looking pretty good. The anti ice TopProp is spectacular... Anywhere near OH time for your engine? Only things left is the... STC tach update Govenor update Where the real value is... T/O distance Climb rate Airspeed generated by HP is expensive... that is why Al Mooney put so much effort into aerodynamics... and minimized CSA... Join the club, when able... Best regards, -a- Quote Link to comment Share on other sites More sharing options...
gsengle Posted January 31, 2019 Report Share Posted January 31, 2019 GS, Your present state of affairs is looking pretty good. The anti ice TopProp is spectacular... Anywhere near OH time for your engine? Only things left is the... STC tach update Govenor update Where the real value is... T/O distance Climb rate Airspeed generated by HP is expensive... that is why Al Mooney put so much effort into aerodynamics... and minimized CSA... Join the club, when able... Best regards, -a- I’m at 2050 hours or so. May consider at overhaul... but right now I can comfortably depart any runway I’d be willing to land on... already adsb compliant. Next project is probably resealing tanks and maybe paint...Sent from my iPhone using Tapatalk 1 Quote Link to comment Share on other sites More sharing options...
0TreeLemur Posted January 31, 2019 Report Share Posted January 31, 2019 17 hours ago, MIm20c said: This is exactly my experience. The strange thing is when I push my C hard it feels like I’m really moving. The same speed in the O feels like I’m an old man driving to the grocery store. Wind noise. Our C is frightfully noisy when I lift the headfones in cruise. Can't wait to put them back on. Quote Link to comment Share on other sites More sharing options...
Hank Posted January 31, 2019 Report Share Posted January 31, 2019 31 minutes ago, Fred₂O said: Wind noise. Our C is frightfully noisy when I lift the headfones in cruise. Can't wait to put them back on. Try it in a 500 fpm descent with cruise power. I'm at the top of the green, but can still hear it with my headset on. Right at 170 mph indicated, whether I'm descending from 3000 msl or 10,000 msl. Quote Link to comment Share on other sites More sharing options...
triple8s Posted February 1, 2019 Report Share Posted February 1, 2019 A speed gain by increase in hp takes a large increase in hp to yield a small increase in speed. I'm talking cruise, now climb? Horsepower increases make for increases in climb that are very easy to feel but cruise speed? The biggest things that will effect cruise are reduced drag and propellor efficiency. Quote Link to comment Share on other sites More sharing options...
ArtVandelay Posted February 1, 2019 Report Share Posted February 1, 2019 Try it in a 500 fpm descent with cruise power. I'm at the top of the green, but can still hear it with my headset on. Right at 170 mph indicated, whether I'm descending from 3000 msl or 10,000 msl. You can put in thicker glass that might help, it’s one the old mod works upgrades.Tom Quote Link to comment Share on other sites More sharing options...
cujet Posted February 1, 2019 Report Share Posted February 1, 2019 On 1/30/2019 at 9:28 PM, StevenL757 said: Partial-throttle operations also compromise efficiency in tuned-induction engine systems such as ours. Partial throttle operation increases engine pumping losses. The engine is performing work creating a lower manifold pressure behind the throttle plate. Note: diesel engines have better efficiency due to compression ratio, diesel fuel has more energy (as much as 18%) per gallon AND there is no throttle plate to increase pumping losses. It's one reason diesels burn so little at idle (and create little heat at idle) Our aircraft engines when well tuned and flown lean of peak, can achieve world class BSFC (HP per weight of fuel consumed) (remember aircraft fuel is purchased in gallons but it's the weight that matters) Partial throttle operation increases the engine's workload and decreases engine efficiency. 1 Quote Link to comment Share on other sites More sharing options...
cujet Posted February 1, 2019 Report Share Posted February 1, 2019 4 hours ago, triple8s said: A speed gain by increase in hp takes a large increase in hp to yield a small increase in speed. I'm talking cruise, now climb? Horsepower increases make for increases in climb that are very easy to feel but cruise speed? The biggest things that will effect cruise are reduced drag and propeller efficiency. Remember, prop efficiency is roughly equivalent to a gain in HP. Quote Hartzell: "Generally, it requires a large increase in propeller efficiency to produce a small increase in cruise speed on an aircraft" https://hartzellprop.com/faq/technical-questions/ However, as many owners of older airplanes now know, some original prop designs were not all that great and large increases in prop efficiency (for our discussion that's 2% or more) are very possible. It's hard to find published prop efficiency numbers. But most conventional props are, I believe, around 80% efficient in cruise. The more modern aircraft do choose more efficient props and it's one part of the optimization strategy for better speed. As I keep mentioning, it's easy to add an antenna or two and increase drag by 6 pounds. It's exceedingly difficult to get 6 pounds more thrust at altitude without a fuel burn penalty. Quote Link to comment Share on other sites More sharing options...
Mcstealth Posted February 1, 2019 Report Share Posted February 1, 2019 On 1/29/2019 at 10:56 PM, Andy95W said: It's mostly the HP, but at the higher speeds the aerodynamic improvements kick in. A few years ago (probably 5) I flew my M20C side-by-side with a friend who owned an Ovation3. I did a write up back then but can't find it now. The interesting thing about it was not the speed, which of course the O3 won, but the fuel flows. As I recall, when we were both at 12 gal per hour, the Ovation was faster. At 10 gph, about the same; at 8gph, my C was faster. And then my friend threw the coals to his Ovation and left me like I was standing still! You have Friends? 1 1 Quote Link to comment Share on other sites More sharing options...
PT20J Posted February 2, 2019 Report Share Posted February 2, 2019 Thrust = drag. To go faster, you have to increase thrust or decrease drag. As noted, decreasing drag is more efficient. Mooney started out with a design that packages 4 people in the smallest wetted area (with a cabin width greater than the Bonanza). The aerodynamic cleanup for the 201 got the low hanging fruit in drag reduction. When Mooney ran out of aerodynamic tricks, it did what everyone else does and went to bigger engines. Quote Link to comment Share on other sites More sharing options...
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