Larrynoel Posted January 27, 2011 Report Posted January 27, 2011 I have an 67 M20C Ranger. This is my first complex airplane. I was wondering what people are using for cruise power for cross country flight. What RPM and Manifold pressure seems to work for you? Thank you Quote
Parker_Woodruff Posted January 27, 2011 Report Posted January 27, 2011 Wide open throttle all the time as long as the lack of bumps allows. RPM where it runs smooth. Mixture depends on altitude. Quote
flight2000 Posted January 27, 2011 Report Posted January 27, 2011 I'm with Parker. Wide Open Throttle and 2500 RPM. MP will be whatever you can get up high, but if I'm down low I'll stay at 25 squared (all dependant on how smooth the air is). If I'm just screwing around the patch, might pull it back to 19 squared and cruise at C172 speeds while enjoying the scenery. Welcome to the forum! Brian Quote
KSMooniac Posted January 27, 2011 Report Posted January 27, 2011 WOT all the time until you're reducing power for pattern entry or starting an instrument approach! Quote
Immelman Posted January 27, 2011 Report Posted January 27, 2011 I'm with the others when I'm going some place. However, I do a fair amount of 'local for fun' flying and see no need to go fast.. its all about enjoying flight and the scenery. In that case I bring the power way, way back and lean agressively, to maintain 100-120 mias. I can fly around @ 5gph if I want to (!) Quote
planebones Posted January 27, 2011 Report Posted January 27, 2011 Your friendly local A&P/IA here to remind new owners of old Mooneys to run a "prop-tach" or other tachometer calibration method on your plane before you run at 2500........My M20-C reads 70rpm low. A lot of guys who brag about their speed are doing so because their tach reads low....I run at 2500/ WOT. (calibrated RPM) ...but I wouldn't run at 2600 all day. ....Ken Quote
danb35 Posted January 27, 2011 Report Posted January 27, 2011 Quote: planebones but I wouldn't run at 2600 all day. ....Ken Quote
acronut Posted January 27, 2011 Report Posted January 27, 2011 Anyone run 24 sq? Thats kind of how I've always run Lycomings in cruise... Doesn't seem to be popular with this Mooney crowd. Just curious the fuel and speed differences to the 25sq in a Mooney Quote
lahso Posted January 27, 2011 Report Posted January 27, 2011 Acronut, I run WOT (24" or below) and 2400 RPM in my 1966 C model. This is what was recommended by my MSC. Quote
AustinChurch Posted January 27, 2011 Report Posted January 27, 2011 I always ran my IO-360's (I've owned 3, 2 Cessna's and 1 Mooney) at 2500 RPM. I found they ran smoother and the plugs stayed cleaner, but run it at whatever RPM/MP that you are comfortable with. I really do not think there is a wrong answer. Quote
acronut Posted January 27, 2011 Report Posted January 27, 2011 I don't have enough time in my Mooney yet but I've always found 2500 to be quite a higher fuel burn for barely any speed increase in other types. Just curious what people see in their Mooneys Quote
OR75 Posted January 27, 2011 Report Posted January 27, 2011 I am a bit confused. What settings do folks use on their J model in cruise at say 8 to 12 thousand ?. Quote
Urs_Wildermuth Posted January 27, 2011 Report Posted January 27, 2011 65' C here. During type transition we were told to run 22"/2300 for best speed/fuel economy, running at about 140 kt TAS and 9.5 gph. (We currently have Avgas prices around $10/USG here, up to $15/USG in some places, so economy is essential). 25 square would indicate around 12 to 15 GPH @ 155 kt TAS? My question would be what is the best setting for equally range and speed, meaning the best compromise? Looking at the POH, I see ultra long range cruise settings of 1800 RPM/17" giving a range of close to 700 NM, but at speeds of a C150. So what are you guys using if you want to go as far as possible at an acceptable speed? And what altitude? It appears to me that 7000-10000 ft is around the most economic altitude? Also those of you who posted of 700NM + Flights here, at what setting and altitudes did you do those? Quote
Immelman Posted January 28, 2011 Report Posted January 28, 2011 Quote: Urs_Wildermuth 65' C here. During type transition we were told to run 22"/2300 for best speed/fuel economy, running at about 140 kt TAS and 9.5 gph. (We currently have Avgas prices around $10/USG here, up to $15/USG in some places, so economy is essential). 25 square would indicate around 12 to 15 GPH @ 155 kt TAS? My question would be what is the best setting for equally range and speed, meaning the best compromise? Looking at the POH, I see ultra long range cruise settings of 1800 RPM/17" giving a range of close to 700 NM, but at speeds of a C150. So what are you guys using if you want to go as far as possible at an acceptable speed? And what altitude? It appears to me that 7000-10000 ft is around the most economic altitude? Also those of you who posted of 700NM + Flights here, at what setting and altitudes did you do those? Quote
flight2000 Posted January 28, 2011 Report Posted January 28, 2011 Quote: danb35 Why not, unless for noise or fuel flow considerations? I'm with the rest, for cruise, full throttle and 2500-2600 RPM, usually LOP (which may or may not work well in a C). Quote
flight2000 Posted January 28, 2011 Report Posted January 28, 2011 Quote: Urs_Wildermuth 65' C here. During type transition we were told to run 22"/2300 for best speed/fuel economy, running at about 140 kt TAS and 9.5 gph. (We currently have Avgas prices around $10/USG here, up to $15/USG in some places, so economy is essential). 25 square would indicate around 12 to 15 GPH @ 155 kt TAS? Quote
Urs_Wildermuth Posted January 28, 2011 Report Posted January 28, 2011 Brian, mine sais "avoid continuous ops between 2000-2550 RPM" and is a HC-C2YK-1. Jesse, I've read the writings of Jonathan Paul, his is an E- Mooney however, different engine. My engine is a carbureted O-360-A1D, 180 HP. Quote
FAST FLIGHT OPTIONS LLC Posted January 28, 2011 Report Posted January 28, 2011 1982 M20K 231 28" 2500 RPM 50 degrees (LOP) TIT 9.5 GPH 175 + KTS 65% power 10K and higher altitudes Quote
Larrynoel Posted January 28, 2011 Author Report Posted January 28, 2011 I have been running at 24 and 24 with the mixture fairly lean in my 67C. My cruise average is 132 kts. I have been flying from Billings MT. to the Bay Area in Ca. My fuel burn is 11 gph. I will try a trip at 25 squard and see what I get. Sounds like I have Been running a little slow. I am going to post another post about 3 blade props because I have one and it may make a differance in my cruise speeds for the better or worse I don't know. Thank all of you guys for your replies. Quote
Parker_Woodruff Posted January 28, 2011 Report Posted January 28, 2011 Quote: Larrynoel I have been running at 24 and 24 with the mixture fairly lean in my 67C. My cruise average is 132 kts. I have been flying from Billings MT. to the Bay Area in Ca. My fuel burn is 11 gph. I will try a trip at 25 squard and see what I get. Sounds like I have Been running a little slow. I am going to post another post about 3 blade props because I have one and it may make a differance in my cruise speeds for the better or worse I don't know. Thank all of you guys for your replies. Quote
carusoam Posted January 29, 2011 Report Posted January 29, 2011 65M20C - 2,400 rpm (2,500 more vibration, 2,350 yellow arc) favorite altitudes: 11,500 - 12,500 ROP only (unable LOP) 94M20R - 2,500 rpm (max rpm available to unmodified Ovation 1) favorite altitudes: 11 - 12,500 (Peak, LOP or ROP) Best regards, -a- Quote
DaV8or Posted January 30, 2011 Report Posted January 30, 2011 I've been watching this thread and I have noticed that most seem to assume that cruise means a trip of hundreds of miles. My trips tend to be more like 60, 80 miles or less. Climbing up to 12,000 ft is kind of silly for me most times. I have been told that if you want to make TBO for sure, you should run at 65% power. At 6-8,000 feet, WOT is not an option for me. I use the POH numbers, so my numbers look more like 21" and 2500 rpm. I have a printed card with percentages from the POH @ 65 and 75 for altitudes from 3,000 up to 12,000 and I refer to that for my settings. It seems to me that percentage of HP for long engine life is the most important factor, so cruise settings totally depend on altitude. Quote
KLRDMD Posted January 30, 2011 Report Posted January 30, 2011 Quote: DaV8or I've been watching this thread and I have noticed that most seem to assume that cruise means a trip of hundreds of miles. My trips tend to be more like 60, 80 miles or less. Climbing up to 12,000 ft is kind of silly for me most times. I have been told that if you want to make TBO for sure, you should run at 65% power. At 6-8,000 feet, WOT is not an option for me. I use the POH numbers, so my numbers look more like 21" and 2500 rpm. I have a printed card with percentages from the POH @ 65 and 75 for altitudes from 3,000 up to 12,000 and I refer to that for my settings. It seems to me that percentage of HP for long engine life is the most important factor, so cruise settings totally depend on altitude. Quote
danb35 Posted January 30, 2011 Report Posted January 30, 2011 Quote: DaV8or I have been told that if you want to make TBO for sure, you should run at 65% power. Quote
Hank Posted January 31, 2011 Report Posted January 31, 2011 Larry-- I have a 70-model C, and my long-term average fuel burn is very glose to 9.0 gph. My "standard practice" varies according to the charts in my POH [OK, already--it actually says "Owner's Manual" on the yellowing cover]. Low altitude: 23"/2300 Medium alt: 23-24"/2400 [keep it below 75% so I can lean it back] Optimum alt: WOT/2500 I recently saw a picture at 10,000 msl, WOT, leaned to 50º rich [should have been leaner], with indicated airspeed of 134 mph. Don't recall the outside temp, but it was last fall coming home from the Carolinas. Don't forget the temperature correction factor on the performance chart, either. +10ºF, -1% power; -10ºF, +1% power. Don't go leaning above 75% total power. I very STRONGLY recommend taking the MAPA PPP to learn the ins and outs of flying your Mooney. If memory serves correctly, there's a formula they publish for our engine [O-360-A1D] something like this: MP + RPM = 47 for 75% power, MP + RPM = 46 for 65% power, MP + RPM = 45 for 55% power. The first one is correct, but I'll need to look up the other two to verify that they aren't 70% and 65%. Your fuel burn appears much too high, even if you were loaded to max. Quote
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