Ovations Needed for Savvy Analysis!

[Txbyker]

4 minutes ago, Jeff_S said:

@Txbyker Hi Russ. I'm not sure why you wouldn't see the reports, as long as your plane is identified correctly in the system. The only other thing I wonder is if there is a minimum # of flights needed to generate the report, and perhaps you don't have that number of flights. But more likely for some reason they don't have you classified as an M20R.  It's a question for Savvy.  BTW, how did you fare in the hurricane?

Jeff, I opened a ticket with Savy.  33 flights loaded, Pro user.  I jacked the plane up and put bags over the gear and the water came in but never got close.  Heading back today to take remove the jacks.  I will post my report to compare to yours when they fix the issue.

Russ

[Txbyker]

Great new analysis tool at Savy.  I really appreciate their support and information.  Jeff, I am going to try to paste your result next to mine.

Jeff

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I have the pixie hole for #5.

 

Jeff

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Russ

 

Here's one that has me puzzled.  The operating manual said normal PSI is 30-60.  However mine usually runs 63-66.  The pick below is one of the strongest PSI's I see.  However you can see that I am mid way through the green on the G-1000 display.  What is everyone else seeing for PSI?  Why would the Acclaim POH say that normal oil pressure is 30-100 vs Ovation 30-60?

Russ

[Bob_Belville]

What are the risks of (slightly) high oil pressure? (I adjusted mine to cruise in the upper half of the green instead of the lower half. As a consequence the oil pressure red lines high for a few seconds on start up. IO360) 

[jetdriven]

 I think has time gone gone on they have realize the benefits of higher oil pressure in cruise. The Acclaim was certified after the ovation so it reflects newer data and newer engine operating philosophy. The newer 172's after 1996 also show much higher oil pressure limits on the gauge although it is the same engine. We've seen engines damaged by low oil pressure but I've never heard of one damaged by High oil pressure. From the Lycoming rep, too high  oil pressure can blow the nose seal on the crankcase. But if he understood how it works, the seal is not subject to gallery pressure at all. Put that engine in a  1979 and 172 and its oil pressure is maximum of 100 , take that same engine bolt it to a 1996 model it's now 125psi.  But the oil pressure is measured at the end of the oil gallery in the new airplanes which translates to 10 or 15 more psi at the oil pump for the old ones  than as they are measured . Verify accuracy on your gauge. But before I go turning down the oil pressure I would rather have It too high than too low. and for what it's worth ours in cruise shows about 95 psi  for the past 500 hours. Their engine cell test sheet Shows 88 psi. It was shipped that way from Lycoming.

Edited September 1, 2017 by jetdriven

[Txbyker]

1 hour ago, jetdriven said:

Thanks Byron and Bob.  I sent a message to Paul at Mooney to see if perhaps the POH is incorrect stating normal Ovation oil pressure is 30-60.  I checked the Acclaim and it states 30-100, same engine.  (Not sure how turbocharge affects oil pressure).  I believe that 3 blade Hartzel may require more PSI for the governor.  Tell me if I am wrong.  The older 2 blade McCauley Ovation POH says normal is 30-60.  I am thinking normal for my plane is 30-100 like the Acclaim where 65 is about right as my gauge indicates.  Just a hunch.

Russ

 

[Jeff_S]

Good data...thanks Russ. Seems like our engines are working pretty similarly. I also questioned the higher oil pressure but figured that my engine has been tested and worked on and rebuilt so many times (three prop strikes from prior owner) that if there were a problem somebody would have caught it. Also, that oil pressure range is right in the middle of the green on the gauge so I wasn't too worried about it.  I didn't realize that the Acclaim has a range of 30-100 psi...it will be good to get input from Mooney on this.

[Txbyker]

11 minutes ago, Jeff_S said:

Good data...thanks Russ. Seems like our engines are working pretty similarly. I also questioned the higher oil pressure but figured that my engine has been tested and worked on and rebuilt so many times (three prop strikes from prior owner) that if there were a problem somebody would have caught it. Also, that oil pressure range is right in the middle of the green on the gauge so I wasn't too worried about it.  I didn't realize that the Acclaim has a range of 30-100 psi...it will be good to get input from Mooney on this.

You asked and it shall be done....haha just got this from Mooney from an earlier request.

As for the POH, no misprints, type-o’s or carry-overs.  There is defiantly a difference between the Ovation and the Acclaim but the chief test pilot told me what you are seeing is normal for the Ovation and he has gone through the certification program for both aircraft. I agree it is on the high side I/A/W the POH but obviously well below red line.      

[Bob_Belville]

Oil pressure markings for my IO360 : red lines are  25 and 100,  green is 55 to 90, and 25-55 & 90-100 are  marked yellow. 

Returning from KOSH at 11,000' Oil Press was 60-70 psi and 197 dF.

[Guest]

Lycoming oil pressure pick ups are on the right side of the engine before the main bearings, Continental oil pressure pick up is on the left side of the engine after the main bearings, hence the lower readings.

Clarence

[carusoam]

Re: prop oil pressure...

Oil pressure for the prop is supplied by the gear pump inside the governor. It goes without any measurement... pressure is controlled by flyweights attached to a conic valve... It only takes a minimum amount of oil pressure to feed the oil to the pump in the gov.

Book smarts and 0360 knowledge only, I have no first hand knowledge of the internal parts of an IO550....

 

I am starting to really like the Savvy presentation.  Except for the part that says 175kts is only average...  

 

Thanks for sharing the details.

Best regards,

-a- 

[kmyfm20s]

PERCENT POWER IN CRUISE

Measures your engine's power output during cruise flight. High power output for extended periods can contribute to reduced fuel efficiency, elevated CHT and reduced cylinder life.

SAVVY SAYS...

The median of your engine's power output during cruise flights is greater than 74% of the cohort, which will make you go fast, but at the cost of reduced cylinder longevity.

SPEED IN CRUISE (K.)

We use TAS if available, otherwise ground speed. Higher speed might be due to high power output, resulting in high CHT and reduced cylinder life. Or possibly operation at higher, more efficient altitudes.

SAVVY SAYS...

Your cruise speed is higher than average when compared with your cohort.

FUEL EFFICIENCY (NM PER GAL.)

Measures your aircraft's fuel efficiency during cruise flight.

SAVVY SAYS...

Your aircraft's fuel efficiency is average when compared to your cohort.

MAXIMUM CHT DURING FLIGHT (DEG. F.)

Measures the maximum CHT attained during each flight, most likely during climb phase. Prolonged periods of high CHT can contribute to reduced cylinder life.

SAVVY SAYS...

Outstanding! The maximum CHTs attained during your flights has been exceptionally low, with a median lower than 80% of the cohort. We think you can expect above-average longevity of your cylinders if you continue operating with your current power settings. Keep doing what you're doing! 

MAXIMUM CHT IN CRUISE (DEG. F.)

Measures the maximum cylinder head temperature (CHT) during the cruise phase of flight, an indication of the stress placed on your engine's reciprocating components. High CHT correlates with reduced longevity of cylinder assemblies.

SAVVY SAYS...

Outstanding! Your cruise CHTs have been exceptionally low, with a median value lower than 71% of the cohort. We think you can expect above-average longevity of your cylinders if you continue operating with your current leaning procedures and/or power settings. Keep doing what you're doing! 

MAXIMIMUM CHT SPREAD IN CRUISE (DEG. F.)

Measures the median temperature spread between your hottest and coolest cylinders at maximum CHT during cruise. The spread is an indication of mixture distribution and the adequacy of cooling airflow to all cylinders.

SAVVY SAYS...

The median value of the maximum CHT spread during cruise flights is higher than 52% of the cohort.

OIL PRESSURE IN CRUISE (PSI)

Measures the average oil pressures during cruise for your flights.

SAVVY SAYS...

Your average oil pressures during cruise have a median value in the mid-range of the cohort. Your oil pressures are in the normal range.

OIL TEMPERATURE IN CRUISE

Measures average oil temperature during cruise.

SAVVY SAYS...

The median of your average oil temperatures during cruise are about average when compared with the cohort. Your oil temperatures are in the normal range.

MAXIMUM FUEL FLOW DURING FLIGHT

Measures maximum fuel flow during flight, most likely during takeoff. Sufficient fuel flow is important for proper cylinder cooling during high power operations

SAVVY SAYS...

Your maximum fuel flow is higher than average when compared with your cohort.

MAXIMUM RPM DURING FLIGHT

Measures maximum rpm during flight, most likely during takeoff. Maximum permitted RPM is necessary for the engine to develop full rated power during takeoff and in initial climb.

SAVVY SAYS...

Your maximum RPM is higher than average when compared with your cohort.

MAXIMUM MAP DURING FLIGHT

Measures maximum manifold pressure during flight, most likely during takeoff. Sufficient MAP, not to exceed redline, is necessary for the engine to develop full rated power during takoff and initial climb

SAVVY SAYS...

Your maximum MP is higher than average when compared with your cohort.

INACTIVITY PERIODS (DAYS)

Measures the number of days your aircraft was inactive between flights. Inactivity can contribute to engine corrosion and reduced life of engine components.

SAVVY SAYS...

Your engine's inactivity is about average when compared to your cohort. Savvy recommends continuing to fly as frequently as possible

[MIm20c]

@kmyfm20s SAVVY SAYS...you are flying really fast while being kind to your engine, bravo!

[kmyfm20s]

I thought I would share my report as well but I can't get my graphs up on my post. I'll try to edit latter when I can get on my PC.

[Jeff_S]

Yeah, would be interesting to see your numbers for comparison. I'm curious how you can be keeping the CHTs down like you are. 

[kortopates]

I just got the Savvy response to your questions from my Savvy colleague Chris that develops the reporting s/w for these reports. Here is his response: 

First of all, thanks so much for the interest being expressed on the forum in what Savvy is doing with Report Cards and Trend Analysis. I appreciate your questions and suggestions. We want to make our reports as useful as we can. I’ll do my best to answer the questions that were raised.

For Report Cards and Trend Analysis reports we include only those flights whose duration exceeds 40 minutes and for which we can detect a cruise segment. The reason we limit the flights is so that we are comparing apples to apples with most of the measures. To identify the cruise segment we use altitude (or OAT as a surrogate for altitude if the engine monitor does not provide altitude) along with stable values of some mix of MAP, FF, RPM, IAS and EGT. After reaching stability we wait 60 seconds before measuring CHT, speed, CHT spread, oil temp and oil pressure.

Percent Power requires RPM, MAP and FF. Lean of peak, Percent Power is a function of FF and compression ratio, because while LOP the engine has an excess of air. ROP we do a lookup on the classic sea level chart that plots power as a function of RPM and MAP. The resulting numbers are adjusted for altitude. How do we tell if the engine is running LOP or LOP? I’ll leave that as an exercise for the reader!

Speed is TAS if available, otherwise we use groundspeed. If the engine monitor does not record groundspeed directly, we calculate it the old fashioned way with time, LAT and LON. This may or may not be the best way to do this because it mixes GS with TAS. Your opinions would be appreciated.

Jeff’s question about when we calculate max CHT is a good one. It’s possible that a one-minute delay is not enough for CHT or oil temp to stabilize. Though if the pilot’s workflow is to level off, reduce power, and lean the engine, then waiting a minute after all these activities are completed might be sufficient. Thoughts?

There was also a question about oil pressure. I just looked at the Type Certificate Data Sheet for the IO-550 and it specifies the “normal” range as 30-60psi for all the models covered by that TCDS, with a 100psi limit for cold oil. Lycoming has a normal range of 55-95psi. I don’t know if an aircraft manufacture can supersede the Continental spec with their own. That’s a good question for Mike Busch who knows these regs inside and out. But then there’s also the fact that the regs and practice sometimes are not completely aligned ;-)

The forum discussion centered on the Report Card. I also encourage you to look at our new Trend Analysis report that expands on the Report Card by plotting individual data points on a time line and looking for trends. Both are available online, on demand.

We have a FAQ you might find interesting:  https://www.savvyaviation.com/ufaqs/report-card-and-trend-analysis/

I’ll turn my attention to providing support for the other Mooney models as soon as I can.

Thanks again for your interest!

 Chris Wrather

Project Manager

SavvyAnalysis 

chris.wrather@savvymx.com 

Edited September 2, 2017 by kortopates

[kortopates]

And Chris was quick and true to his word, Savvy now supports the O-360 powered A,B,C,D,G cohort. Still to come are the E, K, M and TN.

Edited September 2, 2017 by kortopates

[Jeff_S]

That's good info and does help interpret the results.  My feedback on calculating max cruise CHT is based on my own operating parameters, so take this as a sample of one. But when I do level off for cruise, I actually keep both FF and RPM at climb rates until I hit my target TAS, generally around 175 KTAS.  Then I'll pull RPM, let the engine stabilize for a few moments, then go into leaning procedure to find the LOP setting for that flight.  All this definitely takes more than one minute, so that is no doubt why the max cruise CHTs showing in my report are much higher than my actual cruise CHTs.

But if that is how the metric is derived, then at least I can use that info to interpret my personal results. Still, waiting a good 2-3 minutes would likely show a much lower median max CHT in cruise.

Thanks again to the Savvy folks...y'all ROCK!

[Txbyker]

26 minutes ago, Jeff_S said:

That's good info and does help interpret the results.  My feedback on calculating max cruise CHT is based on my own operating parameters, so take this as a sample of one. But when I do level off for cruise, I actually keep both FF and RPM at climb rates until I hit my target TAS, generally around 175 KTAS.  Then I'll pull RPM, let the engine stabilize for a few moments, then go into leaning procedure to find the LOP setting for that flight.  All this definitely takes more than one minute, so that is no doubt why the max cruise CHTs showing in my report are much higher than my actual cruise CHTs.

But if that is how the metric is derived, then at least I can use that info to interpret my personal results. Still, waiting a good 2-3 minutes would likely show a much lower median max CHT in cruise.

Thanks again to the Savvy folks...y'all ROCK!

Ditto

[Txbyker]

Paul, Chris, fantastic tool.  Thanks!

Russ

[Bob_Belville]

Great stuff. I'm curious about TAS reporting. My Aspen calculates TAS and displays it in real time but the JPI EDM 930 does not record that info which I don't think is calculated by the GTN 750. What equipment is giving Savvy TAS info?

[ArtVandelay]

My JPI 830 has a temperature probe, all it needs is the IAS. Unfortunately it doesn't send that info to the GTN, I have to manually enter the temperature. I assume altitude is GPS.

[kortopates]

1 hour ago, Bob_Belville said:

Great stuff. I'm curious about TAS reporting. My Aspen calculates TAS and displays it in real time but the JPI EDM 930 does not record that info which I don't think is calculated by the GTN 750. What equipment is giving Savvy TAS info?

Some of the engine analyzers interface to the GPS includes TAS in addition to groundspeed. G1000 is probably the most common one that does that but some of the experimental ones too. EDM is not one of them unfortunately but groundspeed gets the job done. 

44 minutes ago, teejayevans said:

My JPI 830 has a temperature probe, all it needs is the IAS. Unfortunately it doesn't send that info to the GTN, I have to manually enter the temperature. I assume altitude is GPS.

Not sure I get the connection between temperature probe and IAS. All the air related parameters are coming from air data, the digital air data sensors utilized by glass panels to show you IAS, TAS, Winds aloft, Baro including ALTmsl, VS, OAT, and etc in the G1000/500/600 & Aspen etc.  We can get Altitude from airdata and more commonly from GPS (with ground speed, and lat/long).

[Bob_Belville]

19 minutes ago, kortopates said:

Some of the engine analyzers interface to the GPS includes TAS in addition to groundspeed. G1000 is probably the most common one that does that but some of the experimental ones too. EDM is not one of them unfortunately but groundspeed gets the job done. 

Not sure I get the connection between temperature probe and IAS. All the air related parameters are coming from air data, the digital air data sensors utilized by glass panels to show you IAS, TAS, Winds aloft, Baro including ALTmsl, VS, OAT, and etc in the G1000/500/600 & Aspen etc.  We can get Altitude from airdata and more commonly from GPS (with ground speed, and lat/long).

Paul, I cannot imagine that ground speed is very meaningful when comparing performance. Without knowing the wind how can we compare flights? FWIW, my EDM 930 does not display GS and the value that it stores is nonsensical. I've discussed that issue with JPI and Garmin several times but have not been able to get to the bottom of it. JPI says their box records the GS as received from the Garmin (via RS232) but what gets stored  is very different from what the 750 displays. .   

The Aspen PFD 1000 Pro seems to calculate TAS and the wind vector from the air data (IAS) and heading, probably using OAT and Baro as well - E6-B stuff. I don't think the 750 does the same, does it? It does not display TAS or wind. Does it know OAT, Baro, IAS?

[ArtVandelay]

The Aspen PFD 1000 Pro seems to calculate TAS and the wind vector from the air data (IAS) and heading, probably using OAT and Baro as well - E6-B stuff. I don't think the 750 does the same, does it? It does not display TAS or wind. Does it know OAT, Baro, IAS?

What's annoying is the JPI has the OAT sensor, but either doesn't transmit it to the GTN, or the GTN ignores it, otherwise it could calculate the winds,TAS.

[Bob_Belville]

What's annoying is the JPI has the OAT sensor, but either doesn't transmit it to the GTN, or the GTN ignores it, otherwise it could calculate the winds,TAS.

Is the EDM/GTN communication 2 way? I don't see any evidence that the GTN gets info from either the EDM or the PFD consequently I don't think the GTN knows IAS, OAT, or even BARO/Altitude. It knows GPS speed (GS) and GPS altitude. But I'd love to be wrong, there's a lot of stuff that I don't know and some of the stuff I do know ain't so.

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