Re: Cruise RPM?

[jayherrin@bellsouth.net]

'
Hello Guys,

I have a Warner 165 on my Meyers OTW.  I am curious what RPM you guys use when just flying around.
The engine seems to like about 1500-1600 but I just want to make sure that's not too slow.  For cross country I use about 1800 RPM'S.  Your thoughts please and thanks!

Guitar1'

[tonylowe2]

' Fairchild’s manual for F-24W46 says’ “....cruising RPM is approximately 1950 below 5000 feet and 2000 RPM above this altitude.  In level flight full throttle RPM should be 2150 + or – 50.”  Fairchild says 91% of full throttle RPM in level flight at sea level gives 75% power.  That works out to be those RPM’s recommended.  They use 2150 as max continuous/rated RPM.   The USAAF’s manual for the UC-61/UC-61A (Warner 165 powered) recommends cruise RPM of 1910 in Section II, Pilot’s Operating Instructions.  In Section III, Flight Operation Data, Max Continuous Operation is listed as 2100 RPM, Max Cruise as 1960 RPM, and Minimum Specific Fuel Consumption at 1790 RPM.   I have a 67” pitch Sensenich prop, and I use about 1900 RPM.   Tony Lowe N28522   From: fairchildclub@yahoogroups.com Sent: Monday, August 18, 2014 8:30 AM To: fairchildclub@yahoogroups.com Subject: [fairchildclub] Cruise RPM?    
Hello Guys,

I have a Warner 165 on my Meyers OTW.  I am curious what RPM you guys use when just flying around.
The engine seems to like about 1500-1600 but I just want to make sure that's not too slow.  For cross country I use about 1800 RPM'S.  Your thoughts please and thanks!
Guitar1'

[Ellen Starr]

'Have a W165 on my Fairchild 24.  Use about 18 - 19 inches which gives me about 1850-1900 rpm.  Have been burning 10.5-11.5 gph.  I a bit higher than I have experienced on another 24 with a 165.  What is you fuel burn??

On Monday, August 18, 2014 7:43 AM, "lowea1@comcast.net [fairchildclub]" wrote:


  Fairchild’s manual for F-24W46 says’ “....cruising RPM is approximately 1950 below 5000 feet and 2000 RPM above this altitude.  In level flight full throttle RPM should be 2150 + or – 50.”  Fairchild says 91% of full throttle RPM in level flight at sea level gives 75% power.  That works out to be those RPM’s recommended.  They use 2150 as max continuous/rated RPM.   The USAAF’s manual for the UC-61/UC-61A (Warner 165 powered) recommends cruise RPM of 1910 in Section II, Pilot’s Operating Instructions.  In Section III, Flight Operation Data, Max Continuous Operation is listed as 2100 RPM, Max Cruise as 1960 RPM, and Minimum Specific Fuel Consumption at 1790 RPM.   I have a 67” pitch Sensenich prop, and I use about 1900 RPM.   Tony Lowe N28522   From: fairchildclub@yahoogroups.com Sent: Monday, August 18, 2014 8:30 AM To: fairchildclub@yahoogroups.com Subject: [fairchildclub] Cruise RPM?     Hello Guys, I have a Warner 165 on my Meyers OTW.  I am curious what RPM you guys use when just flying around. The engine seems to like about 1500-1600 but I just want to make sure that's not too slow.  For cross country I use about 1800 RPM'S.  Your thoughts please and thanks! Guitar1 #ygrps-yiv-507841574 #ygrps-yiv-507841574yiv5813136378 #ygrps-yiv-507841574yiv5813136378 -- #ygrps-yiv-507841574yiv5813136378ygrp-mkp { border:1px solid #d8d8d8;font-family:Arial;margin:10px 0;padding:0 10px;} #ygrps-yiv-507841574 #ygrps-yiv-507841574yiv5813136378 #ygrps-yiv-507841574yiv5813136378ygrp-mkp hr { border:1px solid #d8d8d8;} #ygrps-yiv-507841574 #ygrps-yiv-507841574yiv5813136378 #ygrps-yiv-507841574yiv5813136378ygrp-mkp #ygrps-yiv-507841574yiv5813136378hd { color:#628c2a;font-size:85%;font-weight:700;line-height:122%;margin:10px 0;} #ygrps-yiv-507841574 #ygrps-yiv-507841574yiv5813136378 #ygrps-yiv-507841574yiv5813136378ygrp-mkp #ygrps-yiv-507841574yiv5813136378ads { margin-bottom:10px;} #ygrps-yiv-507841574 #ygrps-yiv-507841574yiv5813136378 #ygrps-yiv-507841574yiv5813136378ygrp-mkp .ygrps-yiv-507841574yiv5813136378ad { padding:0 0;} #ygrps-yiv-507841574 #ygrps-yiv-507841574yiv5813136378 #ygrps-yiv-507841574yiv5813136378ygrp-mkp .ygrps-yiv-507841574yiv5813136378ad p 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'

[Jay Herrin]

'Thanks for the replies......My Meyers does not use a manifold pressure gauge just a tachometer.  Takeoff RPM is about 2050-75 and cruise is somewhere between 1600-1900.I prefer the lower RPM'S as I use the airplane in my sightseeing business but don't want to do any permanent damage to my engine.  All thoughts are appreciated!
Jay
Peachtreecitybiplanes.com

Sent from my iPad

On Aug 18, 2014, at 4:25 PM, "Ellen Starr ellengstarr@yahoo.com [fairchildclub]" wrote:

 
Have a W165 on my Fairchild 24.  Use about 18 - 19 inches which gives me about 1850-1900 rpm.  Have been burning 10.5-11.5 gph.  I a bit higher than I have experienced on another 24 with a 165.  What is you fuel burn??

On Monday, August 18, 2014 7:43 AM, "lowea1@comcast.net [fairchildclub]" wrote:


  Fairchild’s manual for F-24W46 says’ “....cruising RPM is approximately 1950 below 5000 feet and 2000 RPM above this altitude.  In level flight full throttle RPM should be 2150 + or – 50.”  Fairchild says 91% of full throttle RPM in level flight at sea level gives 75% power.  That works out to be those RPM’s recommended.  They use 2150 as max continuous/rated RPM.   The USAAF’s manual for the UC-61/UC-61A (Warner 165 powered) recommends cruise RPM of 1910 in Section II, Pilot’s Operating Instructions.  In Section III, Flight Operation Data, Max Continuous Operation is listed as 2100 RPM, Max Cruise as 1960 RPM, and Minimum Specific Fuel Consumption at 1790 RPM.   I have a 67” pitch Sensenich prop, and I use about 1900 RPM.   Tony Lowe N28522   From: fairchildclub@yahoogroups.com Sent: Monday, August 18, 2014 8:30 AM To: fairchildclub@yahoogroups.com Subject: [fairchildclub] Cruise RPM?     Hello Guys, I have a Warner 165 on my Meyers OTW.  I am curious what RPM you guys use when just flying around. The engine seems to like about 1500-1600 but I just want to make sure that's not too slow.  For cross country I use about 1800 RPM'S.  Your thoughts please and thanks! Guitar1


'

[tonylowe2]

' No MP gauge, just the wooden Sensenich.  Don’t know my fuel burn exactly – not really enough hours of steady running yet – but on the 6 hour ferry flight home, below 5000 feet, I thought I got about 11 gph, so it seems right in line with what you’re getting.  The UC-61 manual shows 11.2 gph at 1960 RPM  -- that’s sea level max cruise (75%).  That would have been with a Sensenich fixed-pitch wood prop, probably of 69 inch pitch.   I highly recommend the USAAF UC-61 manual.  You can get it on the internet.  It has good, fairly modern-looking tabulated performance info.   While the Fairchild manual is actually quite good, it contains only the most basic performance info.  Such was the situation in those times, I guess.  Probably we owe our modern organized and tabulated aircraft manuals to those who set up the training programs for our WWII military -- no doubt a rare example of government standardization producing a good or expected outcome.   Cheers! Tony Lowe N28522 From: fairchildclub@yahoogroups.com Sent: Monday, August 18, 2014 3:25 PM To: fairchildclub@yahoogroups.com Subject: Re: [fairchildclub] Cruise RPM?     Have a W165 on my Fairchild 24.  Use about 18 - 19 inches which gives me about 1850-1900 rpm.  Have been burning 10.5-11.5 gph.  I a bit higher than I have experienced on another 24 with a 165.  What is you fuel burn??

On Monday, August 18, 2014 7:43 AM, "lowea1@comcast.net [fairchildclub]" wrote:


  Fairchild’s manual for F-24W46 says’ “....cruising RPM is approximately 1950 below 5000 feet and 2000 RPM above this altitude.  In level flight full throttle RPM should be 2150 + or – 50.”  Fairchild says 91% of full throttle RPM in level flight at sea level gives 75% power.  That works out to be those RPM’s recommended.  They use 2150 as max continuous/rated RPM.   The USAAF’s manual for the UC-61/UC-61A (Warner 165 powered) recommends cruise RPM of 1910 in Section II, Pilot’s Operating Instructions.  In Section III, Flight Operation Data, Max Continuous Operation is listed as 2100 RPM, Max Cruise as 1960 RPM, and Minimum Specific Fuel Consumption at 1790 RPM.   I have a 67” pitch Sensenich prop, and I use about 1900 RPM.   Tony Lowe N28522   From: fairchildclub@yahoogroups.com Sent: Monday, August 18, 2014 8:30 AM To: fairchildclub@yahoogroups.com Subject: [fairchildclub] Cruise RPM?     Hello Guys, I have a Warner 165 on my Meyers OTW.  I am curious what RPM you guys use when just flying around. The engine seems to like about 1500-1600 but I just want to make sure that's not too slow.  For cross country I use about 1800 RPM'S.  Your thoughts please and thanks! Guitar1

'

[John Armbrust]

'No problem... Sorry to hear that! Thanks for letting us know

Christine Armbrust

On Aug 18, 2014, at 17:25, "lowea1@comcast.net [fairchildclub]" wrote:

 
No MP gauge, just the wooden Sensenich.  Don’t know my fuel burn exactly – not really enough hours of steady running yet – but on the 6 hour ferry flight home, below 5000 feet, I thought I got about 11 gph, so it seems right in line with what you’re getting.  The UC-61 manual shows 11.2 gph at 1960 RPM  -- that’s sea level max cruise (75%).  That would have been with a Sensenich fixed-pitch wood prop, probably of 69 inch pitch.   I highly recommend the USAAF UC-61 manual.  You can get it on the internet.  It has good, fairly modern-looking tabulated performance info.   While the Fairchild manual is actually quite good, it contains only the most basic performance info.  Such was the situation in those times, I guess.  Probably we owe our modern organized and tabulated aircraft manuals to those who set up the training programs for our WWII military -- no doubt a rare example of government standardization producing a good or expected outcome.   Cheers! Tony Lowe N28522 From: fairchildclub@yahoogroups.com Sent: Monday, August 18, 2014 3:25 PM To: fairchildclub@yahoogroups.com Subject: Re: [fairchildclub] Cruise RPM?    
Have a W165 on my Fairchild 24.  Use about 18 - 19 inches which gives me about 1850-1900 rpm.  Have been burning 10.5-11.5 gph.  I a bit higher than I have experienced on another 24 with a 165.  What is you fuel burn??

On Monday, August 18, 2014 7:43 AM, "lowea1@comcast.net [fairchildclub]" wrote:


  Fairchild’s manual for F-24W46 says’ “....cruising RPM is approximately 1950 below 5000 feet and 2000 RPM above this altitude.  In level flight full throttle RPM should be 2150 + or – 50.”  Fairchild says 91% of full throttle RPM in level flight at sea level gives 75% power.  That works out to be those RPM’s recommended.  They use 2150 as max continuous/rated RPM.   The USAAF’s manual for the UC-61/UC-61A (Warner 165 powered) recommends cruise RPM of 1910 in Section II, Pilot’s Operating Instructions.  In Section III, Flight Operation Data, Max Continuous Operation is listed as 2100 RPM, Max Cruise as 1960 RPM, and Minimum Specific Fuel Consumption at 1790 RPM.   I have a 67” pitch Sensenich prop, and I use about 1900 RPM.   Tony Lowe N28522   From: fairchildclub@yahoogroups.com Sent: Monday, August 18, 2014 8:30 AM To: fairchildclub@yahoogroups.com Subject: [fairchildclub] Cruise RPM?     Hello Guys, I have a Warner 165 on my Meyers OTW.  I am curious what RPM you guys use when just flying around. The engine seems to like about 1500-1600 but I just want to make sure that's not too slow.  For cross country I use about 1800 RPM'S.  Your thoughts please and thanks! Guitar1


'

[tonylowe2]

' UC-61 manual says 1790 RPM at sea level, with fixed pitch prop (MP ??) is 60% power (99 bhp) and 9.2 gph, and list this as the point of lowest specific fuel consumption.  The figures in the chart actually compute a higher specific fuel consumption (!?).  My rough extrapolations estimate 1600 RPM will deliver about 51% power (85 bhp) with fuel consumption of probably 8 to 8.5 gph.  Again UC-61 USAAF manual last updated 30 May 1944 is available on-line, for free, I think.  Do you have a Warner manual for the 165?  Those are out there, too.  I have a couple.  I can’t put my hands on the most modern one right this moment, but I could swear it had some power/fuel consumption data the older one doesn’t.  Otherwise there is just a list of engine specs and basic performances that is the same as in the F24 manual.   From: fairchildclub@yahoogroups.com Sent: Monday, August 18, 2014 3:56 PM To: fairchildclub@yahoogroups.com Subject: Re: [fairchildclub] Cruise RPM?     Thanks for the replies......My Meyers does not use a manifold pressure gauge just a tachometer.  Takeoff RPM is about 2050-75 and cruise is somewhere between 1600-1900. I prefer the lower RPM'S as I use the airplane in my sightseeing business but don't want to do any permanent damage to my engine.  All thoughts are appreciated!   Jay   Peachtreecitybiplanes.com

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On Aug 18, 2014, at 4:25 PM, "Ellen Starr ellengstarr@yahoo.com [fairchildclub]" wrote:

  Have a W165 on my Fairchild 24.  Use about 18 - 19 inches which gives me about 1850-1900 rpm.  Have been burning 10.5-11.5 gph.  I a bit higher than I have experienced on another 24 with a 165.  What is you fuel burn??

On Monday, August 18, 2014 7:43 AM, "lowea1@comcast.net [fairchildclub]" wrote:


  Fairchild’s manual for F-24W46 says’ “....cruising RPM is approximately 1950 below 5000 feet and 2000 RPM above this altitude.  In level flight full throttle RPM should be 2150 + or – 50.”  Fairchild says 91% of full throttle RPM in level flight at sea level gives 75% power.  That works out to be those RPM’s recommended.  They use 2150 as max continuous/rated RPM.   The USAAF’s manual for the UC-61/UC-61A (Warner 165 powered) recommends cruise RPM of 1910 in Section II, Pilot’s Operating Instructions.  In Section III, Flight Operation Data, Max Continuous Operation is listed as 2100 RPM, Max Cruise as 1960 RPM, and Minimum Specific Fuel Consumption at 1790 RPM.   I have a 67” pitch Sensenich prop, and I use about 1900 RPM.   Tony Lowe N28522   From: fairchildclub@yahoogroups.com Sent: Monday, August 18, 2014 8:30 AM To: fairchildclub@yahoogroups.com Subject: [fairchildclub] Cruise RPM?     Hello Guys, I have a Warner 165 on my Meyers OTW.  I am curious what RPM you guys use when just flying around. The engine seems to like about 1500-1600 but I just want to make sure that's not too slow.  For cross country I use about 1800 RPM'S.  Your thoughts please and thanks! Guitar1

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[John Armbrust]

'Disregard my last... Fast fingers, too fast for my own good... Lol

John Armbrust

On Aug 18, 2014, at 17:27, "John Armbrust krossbow@comcast.net [fairchildclub]" wrote:

 
No problem... Sorry to hear that! Thanks for letting us know

Christine Armbrust

On Aug 18, 2014, at 17:25, "lowea1@comcast.net [fairchildclub]" wrote:

 
No MP gauge, just the wooden Sensenich.  Don’t know my fuel burn exactly – not really enough hours of steady running yet – but on the 6 hour ferry flight home, below 5000 feet, I thought I got about 11 gph, so it seems right in line with what you’re getting.  The UC-61 manual shows 11.2 gph at 1960 RPM  -- that’s sea level max cruise (75%).  That would have been with a Sensenich fixed-pitch wood prop, probably of 69 inch pitch.   I highly recommend the USAAF UC-61 manual.  You can get it on the internet.  It has good, fairly modern-looking tabulated performance info.   While the Fairchild manual is actually quite good, it contains only the most basic performance info.  Such was the situation in those times, I guess.  Probably we owe our modern organized and tabulated aircraft manuals to those who set up the training programs for our WWII military -- no doubt a rare example of government standardization producing a good or expected outcome.   Cheers! Tony Lowe N28522 From: fairchildclub@yahoogroups.com Sent: Monday, August 18, 2014 3:25 PM To: fairchildclub@yahoogroups.com Subject: Re: [fairchildclub] Cruise RPM?    
Have a W165 on my Fairchild 24.  Use about 18 - 19 inches which gives me about 1850-1900 rpm.  Have been burning 10.5-11.5 gph.  I a bit higher than I have experienced on another 24 with a 165.  What is you fuel burn??

On Monday, August 18, 2014 7:43 AM, "lowea1@comcast.net [fairchildclub]" wrote:


  Fairchild’s manual for F-24W46 says’ “....cruising RPM is approximately 1950 below 5000 feet and 2000 RPM above this altitude.  In level flight full throttle RPM should be 2150 + or – 50.”  Fairchild says 91% of full throttle RPM in level flight at sea level gives 75% power.  That works out to be those RPM’s recommended.  They use 2150 as max continuous/rated RPM.   The USAAF’s manual for the UC-61/UC-61A (Warner 165 powered) recommends cruise RPM of 1910 in Section II, Pilot’s Operating Instructions.  In Section III, Flight Operation Data, Max Continuous Operation is listed as 2100 RPM, Max Cruise as 1960 RPM, and Minimum Specific Fuel Consumption at 1790 RPM.   I have a 67” pitch Sensenich prop, and I use about 1900 RPM.   Tony Lowe N28522   From: fairchildclub@yahoogroups.com Sent: Monday, August 18, 2014 8:30 AM To: fairchildclub@yahoogroups.com Subject: [fairchildclub] Cruise RPM?     Hello Guys, I have a Warner 165 on my Meyers OTW.  I am curious what RPM you guys use when just flying around. The engine seems to like about 1500-1600 but I just want to make sure that's not too slow.  For cross country I use about 1800 RPM'S.  Your thoughts please and thanks! Guitar1



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