cruise settings?

[Larrynoel]

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

[Parker_Woodruff]

Wide open throttle all the time as long as the lack of bumps allows.  RPM where it runs smooth.  Mixture depends on altitude.

[flight2000]

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

[KSMooniac]

WOT all the time until you're reducing power for pattern entry or starting an instrument approach!  

[Immelman]

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 (!)

[planebones]

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

[danb35]

Quote: planebones

but I wouldn't run at 2600 all day. ....Ken

[acronut]

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

 

[lahso]

Acronut, I run WOT (24" or below) and 2400 RPM in my 1966 C model. This is what was recommended by my MSC.

[AustinChurch]

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. 

[acronut]

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

[OR75]

I am a bit confused. What settings do folks use on their J model in cruise at say 8 to 12 thousand ?.

[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?

[Immelman]

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?

[flight2000]

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).

[flight2000]

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?

[Urs_Wildermuth]

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.

 

 

[FAST FLIGHT OPTIONS LLC]

1982 M20K 231

28"

2500 RPM

50 degrees (LOP) TIT

9.5 GPH

175 + KTS

65% power

10K and higher altitudes

[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.

[Parker_Woodruff]

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.

[carusoam]

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-

[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.

[KLRDMD]

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.

[danb35]

Quote: DaV8or

I have been told that if you want to make TBO for sure, you should run at 65% power.

[Hank]

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.