280 ro 310

[Alan Maurer]

Hello Mooney People, Taking the plunge and have STC to change Ovation 2 to Ovation 3. Expect shorter take off roll and faster rate of climb.

I don't know exactly what sort of increase in performance I can expect?? Presume cruise speed remains the same. Who else has made the switch?

Thanks

Alan

N913ND Ovation 2GX

[LANCECASPER]

Just now, Alan Maurer said:

Hello Mooney People, Taking the plunge and have STC to change Ovation 2 to Ovation 3. Expect shorter take off roll and faster rate of climb.

I don't know exactly what sort of increase in performance I can expect?? Presume cruise speed remains the same. Who else has made the switch?

Thanks

Alan

N913ND Ovation 2GX

You definitely don't want to leave it at 2700 in cruise - it's loud and you'll go through cylinders. But it's great for take-off and climb in the Ovation.

[Alan Maurer]

Hi, I knew that.....wondered about take off and climb performance 

[A64Pilot]

Isn’t it just a prop governor adjustment? I really don’t know myself so just asking.

What does the STC cost? Surely it comes with performance charts?

Never having flown one but having done performance testing on other aircraft with different engines in identical airframes my guess is it’s real, there is a difference, but it’s not mind blowing.

I’d expect 100 to 200 ft shorter takeoff roll and 100 to 200 FPM increase in climb, but the climb increase is only for a short time, because surely you roll RPM back to save the engine?

My C-210 was 300 HP for 5 min, 285 continuous. It’s 520 made 550 HP by turning 2850 RPM I think. To save the engine once gear and flaps were up, I’d roll the RPM back to 2700 RPM as 2850 was very noisy and lower RPM would help save the engine. Then cruise at 2500 just because it felt relaxed there.

So I’d suspect Mooney guys who had turned it up to 310 would do similar?

I’m purely speculating here, expecting someone or people who actually have one will post and correct me if I’m wrong.

[LANCECASPER]

9 hours ago, Alan Maurer said:

Hi, I knew that.....wondered about take off and climb performance 

The reason I mentioned that,  is a lot of people didn't know that. On the first link below, back in 2014-2015 people were of the opinion just to firewall the controls and leave it there until descent. That eventually resulted in a lot of cylinders being replaced.

In the Ovation on which I did the conversion I found I was off the ground 300-400 feet sooner and I was seeing climbs at easily 1200 FPM still with good forward visibility (roughly cruise climb). You definitely notice the need for more right rudder (or rudder trim) on take-off. The sweet spot for the Ovation is still 8,000-10,000 feet, that doesn't change.  At the airport I operated out of then it was a nice feature but not a game-changer (5000ft runway and 774 MSL).

I'm at an airpark now (3800 ft runway sloped up slightly to the S and 2110 MSL) and have considered it for my Acclaim S. Bob Minnis still owns the Acclaim STC and it needs to be purchased through him

Mooney owns the STC for the Ovation now and you buy the paperwork through an MSC. Some MSCs will discount the STC. 

 

 

A lot has been written on this:

 

[atpdave]

10 hours ago, Alan Maurer said:

[...] Expect shorter take off roll and faster rate of climb. [...]

I had this done recently. Attached (hopefully) are the takeoff and climb charts from the POH supplement. I still cruise at 2400 rpm as before although could do 2550 post-mod.

Pages from POH Supplement-2.pdf

[StevenL757]

20 hours ago, Alan Maurer said:

Hello Mooney People, Taking the plunge and have STC to change Ovation 2 to Ovation 3. Expect shorter take off roll and faster rate of climb.

I don't know exactly what sort of increase in performance I can expect?? Presume cruise speed remains the same. Who else has made the switch?

Thanks

Alan

N913ND Ovation 2GX

Didn’t we have this conversation about a year ago or more?

:-)

[StevenL757]

1 minute ago, StevenL757 said:

Didn’t we have this conversation about a year ago or more?

:-)

Seriously, @LANCECASPER gave a good summary.  For the Ovation, you’ll shave about 500-700 feet on-average off your takeoff roll.  Takeoff at 2700RPM, pull back to 2550RPM after 1000’ AGL.  Leave it there all the way up to cruise altitude, and throughout cruise and descent.  Just adjust your power and fuel as needed.  40-50LOP is your sweet spot.  Cruise speed is roughly 172-176TAS at between 8000-11000 feet with TKS-equipped airplanes.  You’ll certainly notice the upgrade from 280HP once you push the power up for the first time following upgrade.

[M20F]

A Cessna 310 is a great plane. 

[StevenL757]

13 hours ago, A64Pilot said:

Isn’t it just a prop governor adjustment? I really don’t know myself so just asking.

(SL) - Yes.  The modification is known as a “T20” upgrade, which, basically is a governor modification.  Many find they have - in addition - plastic parts (particularly in the MacCauley governors) that need to be changed out to metal parts to complete a mini-overhaul of the governor.

What does the STC cost? Surely it comes with performance charts?

(SL) - Generally, the paperwork alone is $4995, tho costs at various MSCs can vary.  If you need a governor OH and/or modification instrumentation to support the displaying of 2700 RPM, or a prop replacement to support the upgrade, these costs are in addition to the STC.  Yes, the performance chart contained in the STC is posted here.

Never having flown one but having done performance testing on other aircraft with different engines in identical airframes my guess is it’s real, there is a difference, but it’s not mind blowing.

(SL) - Trust me, it’s very noticeable on takeoff…both on hot and cold days.  You WILL notice it.  :-)

I’d expect 100 to 200 ft shorter takeoff roll and 100 to 200 FPM increase in climb, but the climb increase is only for a short time, because surely you roll RPM back to save the engine?

(SL) - It’s actually closer to 400-700 feet, depending on your TO weight.  Takeoffs are at 2700RPM.  Through 1000’ AGL, pull back to 2550 and leave the power up.  Bob Minnis tested this configuration and determined it to be the most optimal takeoff, climb and cruise profile.  No noticeable noise reduction or fuel savings results from pulling lower than 2550RPM at any phase of flight.

My C-210 was 300 HP for 5 min, 285 continuous. It’s 520 made 550 HP by turning 2850 RPM I think. To save the engine once gear and flaps were up, I’d roll the RPM back to 2700 RPM as 2850 was very noisy and lower RPM would help save the engine. Then cruise at 2500 just because it felt relaxed there.

So I’d suspect Mooney guys who had turned it up to 310 would do similar?

(SL) - Yes…as I highlighted above.

I’m purely speculating here, expecting someone or people who actually have one will post and correct me if I’m wrong.

(SL) - All good questions.  Nothing wrong about your post.  :-)

Mind if I take a crack at this (above)?

[Jeff Uphoff]

I bought my 2000 M20R, originally an Ovation2, post-STC, so I can't compare it directly to a pre-upgrade model, but...OMG, this thing takes off and climbs like a DREAM!

I'm based at 1200' MSL and literally in the middle of a tight bowl of mountains, so the extra takeoff & initial-climb oomph without turbocharging is just what the doctor ordered here.

As for cruise...I took this picture over the weekend at 11,000' on my way to New England. Power was set to full throttle, 2550 RPM, and 50 LOP. 182 KTAS on 11.9 GPH? Yes, please!

--Up.

[A64Pilot]

On 8/8/2023 at 9:15 PM, StevenL757 said:

Mind if I take a crack at this (above)?

Thanks, so in other words it can get very expensive or not depending on equipment.

Sort of like the 520 to 550 STC in the 210. Had to replace the 520 anyway, but by the time the STC was purchased along with the new prop and engine instrumentation I decided the cost wasn’t worth it. It wasn’t trivial $$$, but many go that route and almost all are pleased.

It sounds like to me that most of the benefit to the Mooney is T/O and the first 1,000 ft of climb?

 

[StevenL757]

On 8/10/2023 at 10:55 AM, A64Pilot said:

Thanks, so in other words it can get very expensive or not depending on equipment.

Sort of like the 520 to 550 STC in the 210. Had to replace the 520 anyway, but by the time the STC was purchased along with the new prop and engine instrumentation I decided the cost wasn’t worth it. It wasn’t trivial $$$, but many go that route and almost all are pleased.

It sounds like to me that most of the benefit to the Mooney is T/O and the first 1,000 ft of climb?

Yeah, depending on what’s on the airplane prior to the upgrade, it can get expensive, but not unreasonable (everyone’s mileage may vary of course).

520 to 550 in a 210…yep, similar, I agree.

So, takeoff and climb are just the beginning.  The 280HP engine is rated max 2500RPM.  The 310hp upgrade utilizes 2700, with a highly-recommended cruise at 2550, so there’s a benefit.  When I’ve been somewhat-lightly loaded, I’ve managed a 200-300fpm climb all the way to FL200 in two different Ovations.  The 280hp variant would likely struggle to make it above FL170 at the same weights, edge cases aside.

[aviatoreb]

On 8/8/2023 at 9:10 PM, M20F said:

A Cessna 310 is a great plane. 

How’s the Cessna 280?

[M20F]

16 minutes ago, aviatoreb said:

How’s the Cessna 280?

30 less, I thought you knew something about math?

[William Munney]

What it costs:  $5000-$6000 STC, possibly a new propeller.  More wear on the engine.

What you get:  30 HP.  A couple hundred feet less runway on T/O.  Slightly better climb to altitude.  No cruise speed increase….or very little.

It seems like a lot of money for not much benefit to me.  It’s 30 part-time HP.  If i bought it that way I would enjoy it.  If not, I don’t think i would do it.