Realistic TAS for Mooney Ovation

[Mark89114]

Completed another 4 hour leg yesterday and it gave me lots of time to contemplate....

The book number on my Ovation 2 at 65% power is supposed to be 185 knots which I assume is at 50 ROP.  I however was only doing about 165 LOP, if I push up to 50 ROP I get about 170 and the corresponding fuel burn increase.

I run LOP, have the 3 bladed 310 HP upgrade and TKS.  I don't believe any performance numbers are published for the changes.  That leaves me about 15 short of book.  I have seen postings on here that the 3 bladed prop costs a couple of knots, let's say 2-3 and the TKS doesn't publish anything but I have heard a number of 6-8 knots and sometimes more.  In total I am looking at a shortage of 8 to 11 knots based on some guesses and comparing to probably slightly inflated factory numbers.  My engine is low to mid time, seems to fly pretty straight.

I am just curious what everybody else is getting.  No lying please...    

Thanks and Merry Christmas,

Mark 

[BorealOne]

I'm consistently seeing 168 30 LOP at 9000' at 2400 RPM - scimitar prop, 310 HP,  TKS.

[gsengle]

I see 170-175 in the 6-7k foot range running 25-50lop on 13 gph, Ovation 1 with TKS.


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[carusoam]

Rough memory....  10k’

175 ROP... 15 gph, 2500rpm

165 a few degrees LOP... 12.5 gph, 2500rpm

 

With the 310hp...

• cruise speed using 2550rpm increases
• fuel flow increases to 13+ gph

PP thoughts only...

Best regards,

-a-

[Robert C.]

yesterday: 9,500 ft, 2550 rpm, WOT

15 gph 181kts

13.3 gph 175 kts (~50 LOP)

 

[midlifeflyer]

Same as most others, 175 to 180 depending on how aggressively I lean.

[Guest]

Not nearly as fast as most people would have you believe.

Clarence

[Txbyker]

Mark, here are some recent notes.  What MP are you seeing?  Induction leak could lose some MP.

ROP 8000 +100 11C 23.3 2450 17.3gph 176kts

LOP 8000 -35 12C 22.2 2450 13.2gph 172kts

LOP 9000 -20 10C 21.3 2450 13.0gph 171kts

ROP 10000 +100 6C 20.8 2450 17.0gph 175kts

LOP 9000 -10 11C 21.4 2450 12.9gph 173kts

Russ

[Hank]

Wow! For only 45% more fuel, you can carry larger, lighter people and baggage 13% faster than my C! But the bigger cabin would occasionally be nice . . . Anthony says that with the 310hp upgrade, the takeoff roll goes from much longer than mine to a little shorter, too.

           Sorry, I gotta stir the pot sometimes! Nice machines ya'll have here.

[jerryg324]

I see 180 kts true ROP 13.8 gph religiously...  Drop 5 kts LOP

[LANCECASPER]

8 minutes ago, jerryg324 said:

I see 180 kts true ROP 13.8 gph religiously...  Drop 5 kts LOP

Ah nice an M20L to Ovation conversion. I'd recognize those fuel gauges anywhere.

[Hank]

Cool engine analyzer, too. Wondered what it was . . . .

[MIm20c]

31 minutes ago, Hank said:

Wow! For only 45% more fuel, you can carry larger, lighter people and baggage 13% faster than my C! But the bigger cabin would occasionally be nice . . . Anthony says that with the 310hp upgrade, the takeoff roll goes from much longer than mine to a little shorter, too.

           Sorry, I gotta stir the pot sometimes! Nice machines ya'll have here.

My calculations show 15% increase in speed for 30% more fuel.  However, having a 1300fpm climb while doing 140kts is normal in the O and something I need to have the camera ready for the few seconds I can manage it in my C. 

[LANCECASPER]

24 minutes ago, Hank said:

Cool engine analyzer, too. Wondered what it was . . . .

That is a Vision VM1000 that was part of the IO-550 conversion for the M20L. Unfortunately since JPI bought Vision out they no longer support that engine monitor.

[triple8s]

180-185 ROP 280hp toothpick prop 

[Bob_Belville]

10 hours ago, Hank said:

Wow! For only 45% more fuel, you can carry larger, lighter people and baggage 13% faster than my C! But the bigger cabin would occasionally be nice . . . Anthony says that with the 310hp upgrade, the takeoff roll goes from much longer than mine to a little shorter, too.

           Sorry, I gotta stir the pot sometimes! Nice machines ya'll have here.

Yeah and can you imagine the comparison to a the ideal Mooney model? 

[M016576]

Missile at 9500’.... similar performance to an ovation.  This is 20LOP from my flight on Thursday.  My Missile has a 3 bladed prop and TKS.

 

Edited December 23, 2017 by M016576

[mike_elliott]

40 minutes ago, Bob_Belville said:

Yeah and can you imagine the comparison to a the ideal Mooney model? 

You mean the J? Like 158KTS on 8.2 GPH, hauls over 1000# of lard and fuel, has 64 GAL capacity without the need to gut the wings, and the extra 10" so envied by all those that have to ride in the rear   

[Bob_Belville]

41 minutes ago, mike_elliott said:

You mean the J? Like 158KTS on 8.2 GPH, hauls over 1000# of lard and fuel, has 64 GAL capacity without the need to gut the wings, and the extra 10" so envied by all those that have to ride in the rear   

Hey Mike, yeah, that's what I meant... not.

(If you've got it you don't have to exaggerate. A picture is worth... FF was 8.3 https://savvyanalysis.com/flight/2195821/85eaaff0-7163-49d5-a686-60a59b8d0c66.) 

[Jerry 5TJ]

23 hours ago, Mark89114 said:

......  In total I am looking at a shortage of 8 to 11 knots based on some guesses and comparing to probably slightly inflated factory numbers.  My engine is low to mid time, seems to fly pretty straight.....

Your numbers seem about right to me as compared to my Ovation 2 with TKS. 

All of my Mooney airplanes were slow compared to Mooneyspace figures, by the way.  

[MIm20c]

65% of 280 or 310?  What was the fuel flow?  I think Cirrus or Lancair allows 80 or 85 percent power?  I would think 175 lop and 185ish rop should be obtainable. 

[buddy]

I have a 3 blade with 310hp w/o TKS and after reading the article in AOPA about the new Ultra I tried running mine today using the same parameters as in the article. At 6500ft, WOT, 2500rpm, 50 LOP burning 14.2gal/hr I only got 175 KTAS, not even close to 183 KTAS in the article. So I think this is a little advertising BS. I have seen 197 KTAS at 5500ft. though.

For the past 2 yrs. that I’ve owned the Ovation I’ve been using WOT and 2400rpm at 6500ft ROP using 16.7gal/hr and I see about 175 KTAS. I have always ran 40-50 ROP and 2400rpm, WOT at right up to 16K in level flight, I’m not much of a LOP guy but after today I may try 2500rpm, 50 LOP at higher altitudes as long as I can get the same speed using less gas and keeping the cyl. a little cooler.

[carusoam]

It’s easier to be an LOP fan at altitudes above 8k’...

WOT, LOP by a few degrees... not much more.

All cylinders are LOP, converting all the fuel to power.

• 50°F ROP uses about 2gph for cooling CHTs... CHTs are already in control without the extra FF.
• 50°F LOP doesn't use enough fuel available for generating power.... leaving speed and power on the table.

%bhp is limited by altitude, comfortably less than 65%, outside the red box/fin...

You get to choose your RPM...

• Some Os are limited to 2500 (used to be in this camp)
• some use the max 2700 (sound vs comfort)
• some use the TopProp recommended 2550... (tend to stay in this camp)

 

You get to keep an eye on your CHTs

• 380°F is preffered by many
• 320°F is common in cold temps
• FF is key to CHT control.

I usually select altitude as high as possible, but keep below needing O2...  comfort vs. engine out glide distance.

Go O!

Best regards,

-a-

[StevenL757]

6 hours ago, buddy said:

I have a 3 blade with 310hp w/o TKS and after reading the article in AOPA about the new Ultra I tried running mine today using the same parameters as in the article. At 6500ft, WOT, 2500rpm, 50 LOP burning 14.2gal/hr I only got 175 KTAS, not even close to 183 KTAS in the article. So I think this is a little advertising BS. I have seen 197 KTAS at 5500ft. though.

For the past 2 yrs. that I’ve owned the Ovation I’ve been using WOT and 2400rpm at 6500ft ROP using 16.7gal/hr and I see about 175 KTAS. I have always ran 40-50 ROP and 2400rpm, WOT at right up to 16K in level flight, I’m not much of a LOP guy but after today I may try 2500rpm, 50 LOP at higher altitudes as long as I can get the same speed using less gas and keeping the cyl. a little cooler.

Buddy, according to Bob Minnis (creator of the 310 STC, former CMI patent holder, test pilot, etc. etc), 2550 RPM is the optimal RPM setting with the 310HP upgrade applied.  Try this consistently and see if you and your engine are happier with the output.

Steve

[StevenL757]

22 hours ago, jerryg324 said:

I see 180 kts true ROP 13.8 gph religiously...  Drop 5 kts LOP

Jerry - is your KI256 starting to act up?  Unless your TC is the culprit, I'd say you may be ready for an inspection or O/H on that AI, given that 5-degree left bank angle indication.