Ovation and altitudes above 15k

[Max Clark]

22 hours ago, varlajo said:

Vr, Vx, Vy, Va, Vbg, Vfe, Vle, and touchdown speeds with and without flaps at MGW -200 and -600 lbs.

Really like this idea thanks!

[Mark89114]

I think the wide variation is whether airplane has TKS and 310 HP upgrade.  

Supposedly the 3 bladed prop costs a knot and I have heard 7-9 knots for TKS.  Based on my experience seems reasonable.  My airplane is also slightly out of rig and have an engine approaching high time.  

[NickG]

4 hours ago, Mark89114 said:

I think the wide variation is whether airplane has TKS and 310 HP upgrade.  

Supposedly the 3 bladed prop costs a knot and I have heard 7-9 knots for TKS.  Based on my experience seems reasonable.  My airplane is also slightly out of rig and have an engine approaching high time.  

From everything I've heard and comparing similarly configured birds, I think my TKS panels cost about 5 Kts

[Niko182]

I was a little bored today so I figured I’d see what I could get. I was still getting around 300 to 350 fpm at 100 IAS climb approaching 23.

Edited December 7 by Niko182

[exM20K]

On 11/9/2024 at 1:56 PM, mike_elliott said:

Horsepower when flying LOP is determined by FF*13.9 in the higher compression non turbo's acc'd to Mike Busch, so if your a nerd for wanting a percent, you can build a chart.

That is closer to the low compression multiplier according to APS, and valid only LOP. They say 15 and 13.75 for high/low compression.

 

 

Edited December 7 by exM20K
Deleted copyrighted material

[Ragsf15e]

2 hours ago, Niko182 said:

I was a little bored today so I figured I’d see what I could get. I was still getting around 300 to 350 fpm at 100 IAS climb approaching 23.

Wow! Obviously you were light, but that’s showing 170ktas on 8.6gph!  Awesome!

[NickG]

22 hours ago, Niko182 said:

I was a little bored today so I figured I’d see what I could get. I was still getting around 300 to 350 fpm at 100 IAS climb approaching 23.

Nice!!!

[NickG]

On 11/25/2024 at 5:02 PM, Niko182 said:

This was my eagle at 16500. If I knew I was living in Colorado, I would’ve probably considered an acclaim, but this will have to do. I’d agree flying them over 12 doesn’t really get you anything except not hitting a mountain.

I live in the southwest. 11k-16k is in my opinion the O3 sweet spot. Sure, can scream at lower altitudes but not as efficient.

[Ed de C.]

Recently, at 15,000 feet:  163 kts @ 2,500 rpm, 16.6 MP, 10.8 LOP (about 50 degrees LOP), Temp -19C.  3,100 lbs (2008 O3, 310 hp, TKS, 3-blade Hartzell with the newer blades).

A little lower (9k - 12k) I can get 170 kts reliably at WOT, 2,400 rpm and 50 LOP (12 - 12.5 gph).  

I've run it flat out at 8k (WOT, 2,700) leaned to best power.  Best I get is 185 kts.  Book says 197 kts.  

I'm a good 10 kts off book at cruise settings.  Probably all due to TKS.  I've noticed some recent Mooneys have the TKS installed with black silicone edging that smooths the airflow (like all Cirrus).  Planning to contact CAV to see if adding that would make a difference.  Also wondering about flap gap seals (I believe the Acclaim has these).  

I was curious how loud the cabin is in cruise.  The cruise conditions above measure 89 decibels on my I-phone app.  I have nothing to compare that too yet.

Ed

[Ragsf15e]

On 12/13/2024 at 8:00 PM, Ed de C. said:

Recently, at 15,000 feet:  163 kts @ 2,500 rpm, 16.6 MP, 10.8 LOP (about 50 degrees LOP), Temp -19C.  3,100 lbs (2008 O3, 310 hp, TKS, 3-blade Hartzell with the newer blades).

A little lower (9k - 12k) I can get 170 kts reliably at WOT, 2,400 rpm and 50 LOP (12 - 12.5 gph).  

I've run it flat out at 8k (WOT, 2,700) leaned to best power.  Best I get is 185 kts.  Book says 197 kts.  

I'm a good 10 kts off book at cruise settings.  Probably all due to TKS.  I've noticed some recent Mooneys have the TKS installed with black silicone edging that smooths the airflow (like all Cirrus).  Planning to contact CAV to see if adding that would make a difference.  Also wondering about flap gap seals (I believe the Acclaim has these).  

I was curious how loud the cabin is in cruise.  The cruise conditions above measure 89 decibels on my I-phone app.  I have nothing to compare that too yet.

Ed

I don’t have an Ovat/Eagle yet, so take this for what it’s worth… but on my IO-360, I had pretty good balanced injectors and it was noticeably faster just barely LOP vs 50 LOP.  In fact, at those high altitudes where you’re making like ~60% power or less, running at peak might be just fine, still very low fuel burn and definitely faster.  How were your CHTs at 15,000’?  I’m guessing pretty cool.  They’re likely still fine close to peak.  What are your thoughts?

[Ed de C.]

On 12/15/2024 at 12:56 AM, Ragsf15e said:

I don’t have an Ovat/Eagle yet, so take this for what it’s worth… but on my IO-360, I had pretty good balanced injectors and it was noticeably faster just barely LOP vs 50 LOP.  In fact, at those high altitudes where you’re making like ~60% power or less, running at peak might be just fine, still very low fuel burn and definitely faster.  How were your CHTs at 15,000’?  I’m guessing pretty cool.  They’re likely still fine close to peak.  What are your thoughts?

My temps have always run low.  CHTs on the above trip were something like 280F max (in cruise).  My oil was running around 155F in cruise.  Evidently the baffling and sealing are excellent, and all that without cowl flaps on the O.  The oil temp is too low (I have installed a non-factory small oil cooler plate).  I need to install the large (standard) plate, but even then, oil won't get much over 170 in cruise.  We've checked the sensor accuracy and vernatherm.  Highest I ever see is 200F right after runup.  I have 250 hours on an overhauled engine.  Even in summer, most I've ever seen is 380F max in climb out and that was only because I forgot to put the mixture all the way in prior to takeoff (grumble).  Usually, this engine is maxing out in the mid-300s during summer climb (full rich on takeoff, followed by leaning to the white bar on the G1000 engine page, as I pass 1,000 AGL).

That's a good point about % power and running a bit more fuel through the engine.  I would definitely pick up a few knots.  I, too, notice a noticeable surge of power when advancing the mixture from 50 LOP.  So far, this engine seems to be a textbook example of George Braly's and Mike Busch's applied engine theory.

Ed

[Ed de C.]

I dug up my notes from last year's trip to the flight levels.  Niko182 made it higher than I did (I went to FL220).  My results were 200 fpm arriving at that altitude at 105 IAS at 2,700 rpm.  I was light, probably around 3,000 lbs (me and middle fuel level).  My guess is that if I had pulled it back to Niko182's 100 IAS, I might have seen his 300 fpm given the lightness.  Vy is 105, but that's presumably at gross.

I leveled off at FL220 and saw 164 KTAS (117 KIAS) on 10.5 gph, 12.3 MAP, 2,700rpm.  Temp was -25C.  Bood Ox through FL210 was 92 on the canula.

The results in climb were a bit better than book (book is M20R 2GX).  310hp and Acclaim Type S prop.  I was seeing 500fpm through 19,000 @ 105 KIAS.  

Even the naturally aspirated Ovation has very good altitude flexibility with a little patience.  It would be interesting to see if we can duplicate the IAS performance (but do it down low) by matching the MAP and OAT.  

Ed