Nukemzzz Posted June 29, 2020 Report Share Posted June 29, 2020 4 hours ago, MBDiagMan said: No he used the 430 to calculate TAS. He showed me the resulting 152 knots TAS. Refer to Hanks 430 picture to see where TAS is indicated. This is a really savvy guy. I have seen the 430 used as a TAS calculator on the ground. I wish now I would have asked him to take a picture of the 430 screen, the JPI screen and the ASI. I had no idea that on a Mooney forum there would be people skeptical of such efficiency. I’m not sure why this seems impossible from a Mooney with the J mods that make it aerodynamically a J. To clarify. I’m wasn’t being skeptical. I was unaware that the GPS had that as an output. My plane doesn’t have a fancy GPS. Lol I think my E is slow. At 9,5k I was only getting 145MPH IAS ...ROP Not sure but it think that is well south of 156kt TAS Quote Link to comment Share on other sites More sharing options...
wcb Posted June 29, 2020 Report Share Posted June 29, 2020 Just thought I would share this! Same bird as yours with no mods (well other than turbo normalization that became inop for the flight on the way to SC) On the way to SC without TN I got about at 15.5 I got about 130 kts tas at 6.5 gph on the way back with TN at 10.5 I got about 163kts tas at about 9 gph both LOP. Quote Link to comment Share on other sites More sharing options...
MBDiagMan Posted June 29, 2020 Author Report Share Posted June 29, 2020 15 minutes ago, Nukemzzz said: To clarify. I’m wasn’t being skeptical. I was unaware that the GPS had that as an output. My plane doesn’t have a fancy GPS. Lol I think my E is slow. At 9,5k I was only getting 145MPH IAS ...ROP Not sure but it think that is well south of 156kt TAS Saying that the GPS has it as an output could be misleading. It basically has a TAS calculator that you can use that gets a factor or two directly. Mine gets OAT from the JPI. It does some other things on this screen too. Just don’t get the idea that you fly along and go to that screen and read out TAS. The newer tech navigators might do that though. Quote Link to comment Share on other sites More sharing options...
KLRDMD Posted June 29, 2020 Report Share Posted June 29, 2020 6 hours ago, MBDiagMan said: I completely believe that you are correct Paul, but I have gotten the impression that the success of LOP is in the hands of the person adjusting the mixture control. Someone like yourself and several other folks I know will have/are having great success with it. It is not a process to be approached casually without attention to detail. I have observed a few planes get cylinders all too often. These planes are flown by great folks, but not someone who understands everything involved and don’t apply adequate care and attention when setting it up. I’ve also heard from several knowledgeable A&P’s that the engine shops can look at a cylinder and piston set and tell you if it’s been running LOP. I expect that what they are seeing are cylinders that were run LOP by someone who did not have a good working knowledge of the process. I am still a rookie pilot, although a very old one. If I EVER get a decent autopilot where I can climb out and then be able to Take the time to carefully and accurately lean it, I believe there will be a time when I can have the same success with it that you do. Until that point I’ll be burning extra gas. Attached is my Blackstone oil analysis. I bought this airplane in January 2019. All oil analysis prior to that was from the previous owner who flew ROP. The February 2019 oil analysis was a mix of both ROP and LOP. All values after the February 2019 represent LOP operations. The June 2020 analysis has over 200 hours more than it did in the April 2018 analysis yet the oil analysis is remarkably more favorable after running LOP. The engine now has 2,120 SMOH on a 1,700 TBO. Compression changes over the two years were within measurement error. Compressions at the 2020 annual were: #1) 75/80 #2) 73/80 #3) 77/80 #4) 65/80 #5) 76/80 #6) 76/80 Compressions at the 2018 annual were: #1) 72/80 #2) 75/80 #3) 74/80 #4) 69 80 #5) 76/80 #6) 73/80 You tell me, is ROP or LOP better for the engine? 2 1 Quote Link to comment Share on other sites More sharing options...
gsxrpilot Posted June 29, 2020 Report Share Posted June 29, 2020 16 minutes ago, KLRDMD said: Attached is my Blackstone oil analysis. I bought this airplane in January 2019. All oil analysis prior to that was from the previous owner who flew ROP. The February 2019 oil analysis was a mix of both ROP and LOP. All values after the February 2019 represent LOP operations. The June 2020 analysis has over 200 hours more than it did in the April 2018 analysis yet the oil analysis is remarkably more favorable after running LOP. The engine now has 2,120 SMOH on a 1,700 TBO. Compression changes over the two years were within measurement error. Compressions at the 2020 annual were: #1) 75/80 #2) 73/80 #3) 77/80 #4) 65/80 #5) 76/80 #6) 76/80 Compressions at the 2018 annual were: #1) 72/80 #2) 75/80 #3) 74/80 #4) 69 80 #5) 76/80 #6) 73/80 You tell me, is ROP or LOP better for the engine? Wow! 2 1 Quote Link to comment Share on other sites More sharing options...
Ragsf15e Posted June 29, 2020 Report Share Posted June 29, 2020 2 hours ago, MBDiagMan said: Don’t know if it makes any difference, but my ASI was certified for IFR flight not long ago. I do indeed understand and agree with what you’re saying. I did a two way speed run with it not long ago, just fooling around, not scientific. It was at low altitude. I will go look up the data to make sure I don’t incorrectly state it here. I went back and looked at my two way unscientific speed run and made a swag on temp and density altitude. It came in within one knot of what the model J performance table indicated for those conditions. I don’t think the airspeed indicator is certified for ifr. Only your static instruments. Additionally, it can give you a “correct reading” that isn’t your correct airspeed unless you apply the correction from your poh... thus the correction from indicated to calibrated BEFORE using it to figure True. 3 Quote Link to comment Share on other sites More sharing options...
MBDiagMan Posted June 29, 2020 Author Report Share Posted June 29, 2020 1 hour ago, gsxrpilot said: Wow! The oil analysis doesn’t surprise me even a little bit. The clean burn that results from LOP should keep the oil cleaner. The lowered CHT’s will also be conducive to clean oil and should not make metal. As I wrote before, although in different words, as long as the process is done correctly, all is good. Under the right circumstances I will be learning how to use the lean find. As I get more confident in the wing leveler I should be able to do this on a cruise in the near future. 1 Quote Link to comment Share on other sites More sharing options...
MBDiagMan Posted June 29, 2020 Author Report Share Posted June 29, 2020 1 hour ago, KLRDMD said: Attached is my Blackstone oil analysis. I bought this airplane in January 2019. All oil analysis prior to that was from the previous owner who flew ROP. The February 2019 oil analysis was a mix of both ROP and LOP. All values after the February 2019 represent LOP operations. The June 2020 analysis has over 200 hours more than it did in the April 2018 analysis yet the oil analysis is remarkably more favorable after running LOP. The engine now has 2,120 SMOH on a 1,700 TBO. Compression changes over the two years were within measurement error. Compressions at the 2020 annual were: #1) 75/80 #2) 73/80 #3) 77/80 #4) 65/80 #5) 76/80 #6) 76/80 Compressions at the 2018 annual were: #1) 72/80 #2) 75/80 #3) 74/80 #4) 69 80 #5) 76/80 #6) 73/80 You tell me, is ROP or LOP better for the engine? I have never doubted that is good for the engine. I have only said that it must be done correctly. I have fought a hot cylinder since I go the plane and couldn’t try it. My only contention is that it nmustbe done correctly by someone that knows what they’re doing. Quote Link to comment Share on other sites More sharing options...
KLRDMD Posted June 29, 2020 Report Share Posted June 29, 2020 24 minutes ago, MBDiagMan said: I have never doubted that is good for the engine. I have only said that it must be done correctly. I have fought a hot cylinder since I go the plane and couldn’t try it. My only contention is that it nmustbe done correctly by someone that knows what they’re doing. Which cylinder is hot? I have five traditional JPI CHT probes and one that is on the spark plug. The spark plug probe always reads +/- 25º hotter than the others. I know it to be artificially high so I don't worry about that one reading. Do you have one spark plug probe and is that the hot one? 1 Quote Link to comment Share on other sites More sharing options...
KLRDMD Posted June 29, 2020 Report Share Posted June 29, 2020 27 minutes ago, MBDiagMan said: I have never doubted that is good for the engine. I have only said that it must be done correctly. I have fought a hot cylinder since I go the plane and couldn’t try it. My only contention is that it must be done correctly by someone that knows what they’re doing. The correct way is easy and you don't even need a full engine monitor as some people think. You just need a good fuel flow device. Go to cruise altitude and set up the airplane for cruise, I'm assuming that's full throttle (+/- 20-23" MP) and 2500 RPM. Over a period of about one second pull the mixture back to 8.5 GPH (OK, technically 8.6 GPH). Done. You're at 65% power LOP. It really is that easy. I've attached portions of the LOP chart for a Lycoming IO-360 engine at 8.7 compression ratio and 200HP. The chart is FF/HP/%HP while LOP. 3 Quote Link to comment Share on other sites More sharing options...
Ragsf15e Posted June 29, 2020 Report Share Posted June 29, 2020 2 hours ago, Nukemzzz said: To clarify. I’m wasn’t being skeptical. I was unaware that the GPS had that as an output. My plane doesn’t have a fancy GPS. Lol I think my E is slow. At 9,5k I was only getting 145MPH IAS ...ROP Not sure but it think that is well south of 156kt TAS Actually that’s a pretty reasonable speed at 9,500’. Depending on the temp and pressure, you’re in the mid 145ish Ktas or so. Quote Link to comment Share on other sites More sharing options...
MBDiagMan Posted June 29, 2020 Author Report Share Posted June 29, 2020 14 minutes ago, KLRDMD said: Which cylinder is hot? I have five traditional JPI CHT probes and one that is on the spark plug. The spark plug probe always reads +/- 25º hotter than the others. I know it to be artificially high so I don't worry about that one reading. Do you have one spark plug probe and is that the hot one? None! I had a problem with number three running hot, but I think an injector cleared out or something. All four now are running cool and very consistently. That’s why I had not run it lean of peak before. 1 Quote Link to comment Share on other sites More sharing options...
MBDiagMan Posted June 29, 2020 Author Report Share Posted June 29, 2020 You know, even if the numbers we saw yesterday were a little off, if you don’t think our Mooney’s are efficient, compare to a 172 XP with almost exactly the same engine and prop and are even almost 200 pounds lighter weight, with a 130 Knot top speed. My point was that our Mooneys are efficient. If somebody wants to shoot mine down that’s great, but it could be a lot slower and still be more efficient than most GA planes out there. 3 Quote Link to comment Share on other sites More sharing options...
J0nathan225 Posted June 29, 2020 Report Share Posted June 29, 2020 1 hour ago, KLRDMD said: The correct way is easy and you don't even need a full engine monitor as some people think. You just need a good fuel flow device. Go to cruise altitude and set up the airplane for cruise, I'm assuming that's full throttle (+/- 20-23" MP) and 2500 RPM. Over a period of about one second pull the mixture back to 8.5 GPH (OK, technically 8.6 GPH). Done. You're at 65% power LOP. It really is that easy. I've attached portions of the LOP chart for a Lycoming IO-360 engine at 8.7 compression ratio and 200HP. The chart is FF/HP/%HP while LOP. Thoughts on how a surefly changes this data and fuel flow? I have seen the .5 GPH decrease as advertised, but am I running less power now? Typical cruise is as you described it. Quote Link to comment Share on other sites More sharing options...
KLRDMD Posted June 29, 2020 Report Share Posted June 29, 2020 25 minutes ago, J0nathan225 said: Thoughts on how a surefly changes this data and fuel flow? I have seen the .5 GPH decrease as advertised, but am I running less power now? Typical cruise is as you described it. It shouldn't make any difference when LOP. LOP, % power is determined exclusively by fuel flow, nothing else. Quote Link to comment Share on other sites More sharing options...
Ragsf15e Posted June 29, 2020 Report Share Posted June 29, 2020 1 hour ago, KLRDMD said: It shouldn't make any difference when LOP. LOP, % power is determined exclusively by fuel flow, nothing else. I’ve definitely heard this and generally believe it, but timing advance burns more in the cylinder early in the stroke? Wouldn’t that give slightly better power at same ff? I also have a Surefly and have pretty good data showing admittedly small airspeed gains lop at higher altitude where the advance is more. 1 Quote Link to comment Share on other sites More sharing options...
KLRDMD Posted June 29, 2020 Report Share Posted June 29, 2020 Just now, Ragsf15e said: I’ve definitely heard this and generally believe it, but timing advance burns more in the cylinder early in the stroke? Wouldn’t that give slightly better power at same ff? I also have a Surefly and have pretty good data showing admittedly small airspeed gains lop at higher altitude where the advance is more. Airspeed may be different, I have no idea. But if you are LOP, fuel flow alone determines percent power. Quote Link to comment Share on other sites More sharing options...
Nukemzzz Posted June 29, 2020 Report Share Posted June 29, 2020 1 hour ago, KLRDMD said: It shouldn't make any difference when LOP. LOP, % power is determined exclusively by fuel flow, nothing else. Power Output = torque X engine speed - losses and torque usually varies with speed. The hotter and louder the engine the more the losses are. So it’s a little more complicated. Though I don’t know these complications are significant enough to worry about for a fixed speed. . 1 Quote Link to comment Share on other sites More sharing options...
carusoam Posted June 29, 2020 Report Share Posted June 29, 2020 We need an annual LOP v ROP discussion... 1) Mechanic’s can tell if you have been running LOP... this is a true statement... the Cylinders will be physically cleaner with less crud and ash in the cylinder... Actually a good thing... don’t be surprised... 2) Cars are all running LOP... because wasting gas for cooling is a bad idea... 3) It is easy to run LOP, without an engine monitor, safely... 4) Some unfortunate engines can’t get this far into the conversation.... 5) Check the GAMI spread... no fuel injectors required, certainly not GAMI injectors... On a scale of 0.0 to .90... closer to zero is better above .5 expect roughness... over 1.0 you won’t like it... 6) LOP is about 1°F on the lean side... deep LOP is about 50°F... 0°F LOP is at peak. 7) Super deep is about 90°F... ideal conditions are required... 8) For most FI’d engines... Transitioning from ROP to LOP is an infinite sweep of the mixture control... the engine doesn’t notice a thing... 9) 65% BHP... the line of safety for LOP operations... 10) LOP can be run safely when other conditions are met, above this line... 11) The difference between LOP and ROP... one uses excess air to cool the EGT... the other uses excess fuel... too cool the EGT... so the EGT is what counts... and it is cooled to the same amount... the engine has no idea 12) where things go wrong.... the engine doesn’t know this either... bad plugs, bad fuel injectors, bad or missing data.... can allow a pilot to run an engine terribly... 13) Bad fuel distribution can be improved... 14) Bad air distribution is near impossible to change... short of adding curvy pipes... or getting the mouse house out of the intake... 15) Bad spark plugs are easy to change... 16) Stronger sparks can improve some things... don’t celebrate any too soon... 17) Stronger spark plus LOP... May have some advantages... we are talking small percentages of fuel being wasted.... 18) The assumption... LOP burns all of the fuel before exiting the cylinder is pretty well documented... 19) For Emags with stronger sparks... the 100% burn really has to happen, and would take happening faster to make a difference... 20) Either way you slice this discussion.... learn to post your JPI data in Savvy, push the share button, copy the link here... 21) The goal... is to run at peak... burn the fuel completely... burn as much as the engine will allow... And maintain CHTs/TIT... 22) The goal is not going deep LOP... unless CHTs/TIT are a deep concern... 23) The biggest challenges come from... Not having an engine monitor.. Not being able to access the data... Not having it set-up the best way... Not being able to review or share the data... Hey... we should discuss this more often.... Let me know if I missed something... PP thoughts only, not a mechanic.... Best regards, -a- 1 1 Quote Link to comment Share on other sites More sharing options...
MikeOH Posted June 30, 2020 Report Share Posted June 30, 2020 13 hours ago, Hank said: Several clicks of the big knob. Enter OAT and altimeter setting, it shows TAS, wind speed and direction. Ah, it's just an expensive E6B! So, you must enter CAS using the POH correction from IAS (airspeed indicator itself may have a few percent error. Ref: TSO C2b), along with OAT (error?) and altimeter/baro (more error). It also looks like you have to enter magnetic heading after compass card correction (how accurate is that and when was it last calibrated?) Possibly declination error, as well. All of these error sources could easily add up to 5%, or more. That's 7 or 8 knots at 150 kts. The only accurate method I'm aware of for GA is the 3-way horse-shoe method: Ref: Horseshoe Heading Technique; David F. Rogers; http://www.nar-associates.com/technical-flying/horseshoe_heading/horseshoehead_screen.pdf Quote Link to comment Share on other sites More sharing options...
MBDiagMan Posted June 30, 2020 Author Report Share Posted June 30, 2020 (edited) Correct. For this function it serves as no more than an E6B. It’s no different than any calculator. Garbage in, garbage out. Of course as a navigator it’s worth much more. In the right circumstance it can seem invaluable. Just curious though. What if the instrumentation has errors when doing the three way method? Just askn’. Edited June 30, 2020 by MBDiagMan Quote Link to comment Share on other sites More sharing options...
Hank Posted June 30, 2020 Report Share Posted June 30, 2020 9 minutes ago, MikeOH said: Ah, it's just an expensive E6B! So, you must enter CAS using the POH correction from IAS (airspeed indicator itself may have a few percent error. Ref: TSO C2b), along with OAT (error?) and altimeter/baro (more error). It also looks like you have to enter magnetic heading after compass card correction (how accurate is that and when was it last calibrated?) Possibly declination error, as well. All of these error sources could easily add up to 5%, or more. That's 7 or 8 knots at 150 kts. The only accurate method I'm aware of for GA is the 3-way horse-shoe method: Ref: Horseshoe Heading Technique; David F. Rogers; http://www.nar-associates.com/technical-flying/horseshoe_heading/horseshoehead_screen.pdf It's a WAAS GPS navigator, it knows both heading and track, and declination is not an issue. I do have to enter OAT and altimeter setting and check / correct IAS --> CAS. It makes a great whiz wheel and calculates TAS, headwind direction and strength (just not the headwind component). Quote Link to comment Share on other sites More sharing options...
Hank Posted June 30, 2020 Report Share Posted June 30, 2020 8 minutes ago, MBDiagMan said: Correct. For this function it serves as no more than an E6B. It’s no different than any calculator. Garbage in, garbage out. Of course as a navigator it’s worth much more. In the right circumstance it can seem invaluable. Just curious though. What if the instrumentation has errors when doing the three way method? Just ask in’. Don't forget your calculator. Ever punched in 2+2 and seen "3.9999999"? I have . . . . Wonderful Casio and TI devices . . . . At work, I live by Excel but can't use its results in official reports, Especially for statistics--for that, I must use Minitab. This is the 4th medical manufacturer I've worked for, all with this same rule . . . . So something is afoot, I just don't know exactly what. Don't forget calculation errors, too. Plus fat-finger mistakes. But Garmin doesn't need heading or track input, and declination doesn't exist for GPS. Quote Link to comment Share on other sites More sharing options...
Hank Posted June 30, 2020 Report Share Posted June 30, 2020 1 hour ago, carusoam said: . . . . 23) The biggest challenges come from... Not having an engine monitor.. Not being able to access the data... Not having it set-up the best way... Not being able to review or share the data... Hey... we should discuss this more often.... Let me know if I missed something... You missed the biggest challenge of all--having a carbureted Lycoming engine! Quote Link to comment Share on other sites More sharing options...
MBDiagMan Posted June 30, 2020 Author Report Share Posted June 30, 2020 13 minutes ago, Hank said: It's a WAAS GPS navigator, it knows both heading and track, and declination is not an issue. I do have to enter OAT and altimeter setting and check / correct IAS --> CAS. It makes a great whiz wheel and calculates TAS, headwind direction and strength (just not the headwind component). Mine gets OAT from the JPI. Quote Link to comment Share on other sites More sharing options...
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