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		Strasnuts
 
 
  Joined: 10 Feb 2009 Posts: 502 Location: Salt Lake City, UT
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				 Posted: Sat Jul 31, 2010 12:37 pm    Post subject: KOSH flight fuel expense | 
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				Just wanted to put some numbers out for who ever is interested.
 
 I flew Scott Schmidt's RV-10 out to OSH from BTF
 My route was exactly 2133nm there and back (stopped at Tim O)
 My fuel cost was exactly 803 dollars
 My Fuel quantity was exactly 172.19 giving average fuel cost of 4.66
 My flight time was around 13.5 hours there and back
 Running LOP from BTF to OSH first half 12500 and second half ROP at 2000
 Running LOP from OSH to BTF first half at 12500 and second half 10500
 
 Only stopped once on the way home at the half way point (KPIR)
 
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RV-10 SB N801VR Flying
 
780 Hours
 
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		Tim Olson
 
 
  Joined: 25 Jan 2007 Posts: 2882
 
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				 Posted: Sat Jul 31, 2010 12:55 pm    Post subject: KOSH flight fuel expense | 
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				Believe it or not, at that 12-14mpg (statute rough number) you'll find  
 that you can sometimes do even better than that, getting up near  
 18mpg.   It's amazing how efficient you can be.  If you want to feel  
 even better, use the road miles, but flight gallons....because you  
 cover an "effective distance" when going by air that may save 25% of  
 the miles or more.  It makes the rv-10 compare well with a car or  
 truck for some trips.  I'm going on one soon where the car time is 7  
 hours but rv10 time is 1.75.  Turns into a no brainer on which way I  
 can do it the easiest.
 Tim
 
 On Jul 31, 2010, at 3:37 PM, "Strasnuts" <sean(at)braunandco.com> wrote:
 
  	  | Quote: | 	 		   
 
  Just wanted to put some numbers out for who ever is interested.
 
  I flew Scott Schmidt's RV-10 out to OSH from BTF
  My route was exactly 2133nm there and back (stopped at Tim O)
  My fuel cost was exactly 803 dollars
  My Fuel quantity was exactly 172.19 giving average fuel cost of 4.66
  My flight time was around 13.5 hours there and back
  Running LOP from BTF to OSH first half 12500 and second half ROP at  
  2000
  Running LOP from OSH to BTF first half at 12500 and second half 10500
 
  --------
  Cust. #40936
  RV-10 SB Fuselage
  N801VR reserved
 
 
  Read this topic online here:
 
  http://forums.matronics.com/viewtopic.php?p=306966#306966
 
 
 | 	 
 
 
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		partner14
 
 
  Joined: 12 Jan 2008 Posts: 540 Location: Granbury Texas
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				 Posted: Sat Jul 31, 2010 1:28 pm    Post subject: KOSH flight fuel expense | 
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				Yep, they say air miles are usually 15% shorter, but some of the time it's a LOT shorter.  Here's a shot of my basic vfr panel on the way to Osh a week ago Friday.  I know, it doesn't have TAS, never could get the oat to work... will send to Rob at AFS this winter.  All that being said, at 11,500', wot, 1,990 rpm, 181 knots, with a fuel burn of 9.1 gph aint bad.
  Tim, Bob, Bob, Bill, Gary, Neal, Deems, Scott (I mean John), Bryan, Geoff...and a few more... it was great meeting some of you for the first time, and seeing the rest of you again.  Got back yesterday after a visit to Kim's relatives in Janesville, WI
  Don McDonald
 
 --- On Sat, 7/31/10, Tim Olson <Tim(at)MyRV10.com> wrote:
 
   	  | Quote: | 	 		  
 From: Tim Olson <Tim(at)MyRV10.com>
 Subject: Re: KOSH flight fuel expense
 To: "rv10-list(at)matronics.com" <rv10-list(at)matronics.com>
 Date: Saturday, July 31, 2010, 1:55 PM
 
  --> RV10-List message posted by: Tim Olson <Tim(at)myrv10.com (Tim(at)myrv10.com)>
 
 Believe it or not, at that 12-14mpg (statute rough number) you'll find that you can sometimes do even better than that, getting up near 18mpg.   It's amazing how efficient you can be.  If you want to feel even better, use the road miles, but flight gallons....because you cover an "effective distance" when going by air that may save 25% of the miles or more.  It makes the rv-10 compare well with a car or truck for some trips.  I'm going on one soon where the car time is 7 hours but rv10 time is 1.75.  Turns into a no brainer on which way I can do it the easiest.
 Tim
 
 On Jul 31, 2010, at 3:37 PM, "Strasnuts" <sean(at)braunandco.com (sean(at)braunandco.com)> wrote:
 
  	  | Quote: | 	 		   --> RV10-List message posted by: "Strasnuts" <sean(at)braunandco.com (sean(at)braunandco.com)>
  
  Just wanted to put some numbers out for who ever is interested.
  
  I flew Scott Schmidt's RV-10 out to OSH from BTF
  My route was exactly 2133nm there and back (stopped at Tim O)
  My fuel cost was exactly 803 dollars
  My Fuel quantity was exactly 172.19 giving average fuel cost of 4.66
  My flight time was around 13.5 hours there and back
  Running LOP from BTF to OSH first half 12500 and second half ROP at 2000
  Running LOP from OSH to BTF first half at 12500 and second half 10500
  
  --------
  Cust. #40936
  RV-10 SB Fuselage
  N801VR reserved
  
  
  
   
  Read this topic online here:
  
  http://forums.matronics.com/viewtopic.php?p=306966#306966
  
  t; 
 
 | 	  
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          [quote][b]
 
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  http://www.matronics.com/Navigator?RV10-List |  
  |  
 
 
 
  
 _________________ Don A. McDonald
 
40636 | 
			 
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		partner14
 
 
  Joined: 12 Jan 2008 Posts: 540 Location: Granbury Texas
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				 Posted: Sat Jul 31, 2010 1:31 pm    Post subject: KOSH flight fuel expense | 
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				Ok, so I forgot to attach the pic....
   
  Yep, they say air miles are usually 15% shorter, but some of the time it's a LOT shorter.  Here's a shot of my basic vfr panel on the way to Osh a week ago Friday.  I know, it doesn't have TAS, never could get the oat to work... will send to Rob at AFS this winter.  All that being said, at 11,500', wot, 1,990 rpm, 181 knots, with a fuel burn of 9.1 gph aint bad.
  Tim, Bob, Bob, Bill, Gary, Neal, Deems, Scott (I mean John), Bryan, Geoff...and a few more... it was great meeting some of you for the first time, and seeing the rest of you again.  Got back yesterday after a visit to Kim's relatives in Janesville, WI
  Don McDonald
 --- On Sat, 7/31/10, Tim Olson <Tim(at)MyRV10.com> wrote:
 
   	  | Quote: | 	 		  
 From: Tim Olson <Tim(at)MyRV10.com>
 Subject: Re: KOSH flight fuel expense
 To: "rv10-list(at)matronics.com" <rv10-list(at)matronics.com>
 Date: Saturday, July 31, 2010, 1:55 PM
 
  --> RV10-List message posted by: Tim Olson <Tim(at)myrv10.com (Tim(at)myrv10.com)>
 
 Believe it or not, at that 12-14mpg (statute rough number) you'll find that you can sometimes do even better than that, getting up near 18mpg.   It's amazing how efficient you can be.  If you want to feel even better, use the road miles, but flight gallons....because you cover an "effective distance" when going by air that may save 25% of the miles or more.  It makes the rv-10 compare well with a car or truck for some trips.  I'm going on one soon where the car time is 7 hours but rv10 time is 1.75.  Turns into a no brainer on which way I can do it the easiest.
 Tim
 
 On Jul 31, 2010, at 3:37 PM, "Strasnuts" <sean(at)braunandco.com (sean(at)braunandco.com)> wrote:
 
  	  | Quote: | 	 		   --> RV10-List message posted by: "Strasnuts" <sean(at)braunandco.com (sean(at)braunandco.com)>
  
  Just wanted to put some numbers out for who ever is interested.
  
  I flew Scott Schmidt's RV-10 out to OSH from BTF
  My route was exactly 2133nm there and back (stopped at Tim O)
  My fuel cost was exactly 803 dollars
  My Fuel quantity was exactly 172.19 giving average fuel cost of 4.66
  My flight time was around 13.5 hours there and back
  Running LOP from BTF to OSH first half 12500 and second half ROP at 2000
  Running LOP from OSH to BTF first half at 12500 and second half 10500
  
  --------
  Cust. #40936
  RV-10 SB Fuselage
  N801VR reserved
  
  
  
   
  Read this topic online here:
  
  http://forums.matronics.com/viewtopic.php?p=306966#306966
  
  t; 
 
 | 	  
  | 	 
 
 
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  http://www.matronics.com/Navigator?RV10-List |  
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 _________________ Don A. McDonald
 
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		Kelly McMullen
 
 
  Joined: 16 Apr 2008 Posts: 1188 Location: Sun Lakes AZ
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				 Posted: Sat Jul 31, 2010 2:15 pm    Post subject: KOSH flight fuel expense | 
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				I'm slightly confused. It appears your indicated airspeed on the mechanical gauge is in knots, around 125, with the EFIS in mph at around 144. Not sure why you would want to not match units. That would translate to around 148kt TAS at std temp (-8C). So you were getting around a 33kt tailwind? Also not sure why you would run at 52% power(assuming LOP) unless you had strong tailwind. With that kind of tailwind, could have been over 200kts GS.  
  But of course that is the beauty of home built...we can all do it our way, no matter what the peanut gallery thinks, much less the big bad feds against aviation.
 
 On Sat, Jul 31, 2010 at 2:31 PM, Don McDonald <building_partner(at)yahoo.com (building_partner(at)yahoo.com)> wrote:
  [quote] Ok, so I forgot to attach the pic....
 
   
  Yep, they say air miles are usually 15% shorter, but some of the time it's a LOT shorter.  Here's a shot of my basic vfr panel on the way to Osh a week ago Friday.  I know, it doesn't have TAS, never could get the oat to work... will send to Rob at AFS this winter.  All that being said, at 11,500', wot, 1,990 rpm, 181 knots, with a fuel burn of 9.1 gph aint bad.
   Tim, Bob, Bob, Bill, Gary, Neal, Deems, Scott (I mean John), Bryan, Geoff...and a few more... it was great meeting some of you for the first time, and seeing the rest of you again.  Got back yesterday after a visit to Kim's relatives in Janesville, WI
   Don McDonald
  
 [b]
 
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  http://www.matronics.com/Navigator?RV10-List |  
  |  
 
 
 
  
 _________________ Kelly McMullen
 
A&P/IA, EAA Tech Counselor
 
KCHD | 
			 
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		partner14
 
 
  Joined: 12 Jan 2008 Posts: 540 Location: Granbury Texas
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				 Posted: Sat Jul 31, 2010 7:08 pm    Post subject: KOSH flight fuel expense | 
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				Kelly, you sure have me confused.  The Efis and the round dial ASI show the exact same numbers.... the inside ring shows 145 mph (126kt).... and you think it was 17 degrees F at 11,500.. if it were we certainly would have been using the heater... it was more like 70 degrees F.  These pics were shot about 3pm.  I set my 496 using knots because quite a few guys were using knots back in Calif when we would be flying to lunch etc., and I did all my stall tests and cross training in mph (per Van).
  Check the weather on that day you will find that the winds were mostly quartering tail at about 15kts.  Where the heck did you arrive at a TAS of 148kts?  Ground speed was 181kts or 208mph.  I have found that I lose very little speed when reducing rpm, and my fuel burn and temperatures are excellent.  I suspect most 10's can't do this because they don't have the same combination (high hp and 3 blade MT).  I run this setting, around 2,000 rpm, no matter what the wind is.
  BTW, on the way home from Osh I was catching 3 other rv's in front of me with a headwind.  Sure, I could run slightly faster, but then the fuel burn goes to between 10.5 and 11.5.   10% to 20% more fuel burn for 1% to 3% more speed.
  Sounds like a no brainer to me.
  Don
 
 --- On Sat, 7/31/10, Kelly McMullen <apilot2(at)gmail.com> wrote:
 
   	  | Quote: | 	 		  
 From: Kelly McMullen <apilot2(at)gmail.com>
 Subject: Re: KOSH flight fuel expense
 To: rv10-list(at)matronics.com
 Date: Saturday, July 31, 2010, 3:13 PM
 
  I'm slightly confused. It appears your indicated airspeed on the mechanical gauge is in knots, around 125, with the EFIS in mph at around 144. Not sure why you would want to not match units. That would translate to around 148kt TAS at std temp (-8C). So you were getting around a 33kt tailwind? Also not sure why you would run at 52% power(assuming LOP) unless you had strong tailwind. With that kind of tailwind, could have been over 200kts GS.  
 But of course that is the beauty of home built...we can all do it our way, no matter what the peanut gallery thinks, much less the big bad feds against aviation.
 
  On Sat, Jul 31, 2010 at 2:31 PM, Don McDonald <building_partner(at)yahoo.com (building_partner(at)yahoo.com)> wrote:
   	  | Quote: | 	 		       Ok, so I forgot to attach the pic....
   
    
  Yep, they say air miles are usually 15% shorter, but some of the time it's a LOT shorter.  Here's a shot of my basic vfr panel on the way to Osh a week ago Friday.  I know, it doesn't have TAS, never could get the oat to work... will send to Rob at AFS this winter.  All that being said, at 11,500', wot, 1,990 rpm, 181 knots, with a fuel burn of 9.1 gph aint bad.
  Tim, Bob, Bob, Bill, Gary, Neal, Deems, Scott (I mean John), Bryan, Geoff...and a few more... it was great meeting some of you for the first time, and seeing the rest of you again.  Got back yesterday after a visit to Kim's relatives in Janesville, WI
  Don McDonald
  
 
 
 get=_blank rel=nofollow>http://www.matronics.com/Navigator?RV10-List
 =nofollow>http://forums.matronics.com
 blank rel=nofollow>http://www.matronics.com/contribution
 
  | 	  
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                [quote][b]
 
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  |  
 
 
 
  
 _________________ Don A. McDonald
 
40636 | 
			 
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		Kelly McMullen
 
 
  Joined: 16 Apr 2008 Posts: 1188 Location: Sun Lakes AZ
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				 Posted: Sat Jul 31, 2010 8:46 pm    Post subject: KOSH flight fuel expense | 
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				OK. Inner ring of the round dial isn't visible to me in the picture.
 Nor was any OAT, so I assumed std conditions, a bad assumption on my
 part. Obviously you were warmer, which puts your TAS up to 156kts.
 Still means a 25kt tailwind, not 15.
 IF you were LOP, which I don't know...the formula for a stock
 compression IO-540 is FF*14.9=HP. That would be 9.1gph*14.9 or
 135.6hp. Divided by 260hp gives approx 52% power. Not exactly a high
 power setting. For a normally aspirated engine with 8.5 compression at
 11,500 the only way you will get higher power is to turn more rpm and
 burn more fuel. Granted you are getting great economy, but it isn't
 efficiency of the engine or low rpm by themselves, it is the low power
 setting that is getting you the economy. If you reduced further, to
 around 40% power, you would approach max range figures, but at a
 slower speed. You are already giving up 10-15kts for the sake of fuel
 economy, as a -10 should be capable of between 165-170kts TAS, perhaps
 as much as 175 at 75% power(Van's figures converted to kts). To do
 that LOP you would have to be low enough make that much power,
 probably in the 7500-8500 alt range running 2600-2650 rpm.  Running
 LOP to get 75% power you have to burn 13.1 gph. That is the physics.
 Is the extra speed worth the extra gas?
 Just one of the many decisions we have to make..speed vs fuel burn. I
 just wanted to point out that your TAS was no where near 181kts on
 that fuel burn.  If you are running ROP the power figure would be even
 lower. If your engine is higher than stock compression, the fuel/power
 factor would change to a little higher number and your percent power
 might be a percent or two more, nothing drastic.
 
 On Sat, Jul 31, 2010 at 8:07 PM, Don McDonald
 <building_partner(at)yahoo.com> wrote:
  	  | Quote: | 	 		  
  Kelly, you sure have me confused.  The Efis and the round dial ASI show the exact same numbers.... the inside ring shows 145 mph (126kt).... and you think it was 17 degrees F at 11,500... if it were we certainly would have been using the heater... it was more like 70 degrees F.  These pics were shot about 3pm.  I set my 496 using knots because quite a few guys were using knots back in Calif when we would be flying to lunch etc., and I did all my stall tests and cross training in mph (per Van).
  Check the weather on that day you will find that the winds were mostly quartering tail at about 15kts.  Where the heck did you arrive at a TAS of 148kts?  Ground speed was 181kts or 208mph.  I have found that I lose very little speed when reducing rpm, and my fuel burn and temperatures are excellent.  I suspect most 10's can't do this because they don't have the same combination (high hp and 3 blade MT).  I run this setting, around 2,000 rpm, no matter what the wind is.
  BTW, on the way home from Osh I was catching 3 other rv's in front of me with a headwind.  Sure, I could run slightly faster, but then the fuel burn goes to between 10.5 and 11.5.   10% to 20% more fuel burn for 1% to 3% more speed.
  Sounds like a no brainer to me.
  Don
 
  --- On Sat, 7/31/10, Kelly McMullen <apilot2(at)gmail.com> wrote:
 
  From: Kelly McMullen <apilot2(at)gmail.com>
  Subject: Re: KOSH flight fuel expense
  To: rv10-list(at)matronics.com
  Date: Saturday, July 31, 2010, 3:13 PM
 
  I'm slightly confused. It appears your indicated airspeed on the mechanical gauge is in knots, around 125, with the EFIS in mph at around 144. Not sure why you would want to not match units. That would translate to around 148kt TAS at std temp (-8C). So you were getting around a 33kt tailwind? Also not sure why you would run at 52% power(assuming LOP) unless you had strong tailwind. With that kind of tailwind, could have been over 200kts GS.  
  But of course that is the beauty of home built...we can all do it our way, no matter what the peanut gallery thinks, much less the big bad feds against aviation.
 
  On Sat, Jul 31, 2010 at 2:31 PM, Don McDonald <building_partner(at)yahoo.com> wrote:
 
  Ok, so I forgot to attach the pic....
 
  Yep, they say air miles are usually 15% shorter, but some of the time it's a LOT shorter.  Here's a shot of my basic vfr panel on the way to Osh a week ago Friday.  I know, it doesn't have TAS, never could get the oat to work... will send to Rob at AFS this winter.  All that being said, at 11,500', wot, 1,990 rpm, 181 knots, with a fuel burn of 9.1 gph aint bad.
  Tim, Bob, Bob, Bill, Gary, Neal, Deems, Scott (I mean John), Bryan, Geoff...and a few more... it was great meeting some of you for the first time, and seeing the rest of you again.  Got back yesterday after a visit to Kim's relatives in Janesville, WI
  Don McDonald
  get=_blank rel=nofollow>http://www.matronics.com/Navigator?RV10-List
  =nofollow>http://forums.matronics.com
  blank rel=nofollow>http://www.matronics.com/contribution
 
 
 | 	 
 
 
  |  | - The Matronics RV10-List Email Forum - |  |   |  Use the List Feature Navigator to browse the many List utilities available such as the Email Subscriptions page, Archive Search & Download, 7-Day Browse, Chat, FAQ, Photoshare, and much more:
 
  http://www.matronics.com/Navigator?RV10-List |  
  |  
 
 
 
  
 _________________ Kelly McMullen
 
A&P/IA, EAA Tech Counselor
 
KCHD | 
			 
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		Strasnuts
 
 
  Joined: 10 Feb 2009 Posts: 502 Location: Salt Lake City, UT
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				 Posted: Mon Aug 02, 2010 12:13 pm    Post subject: Re: KOSH flight fuel expense | 
				     | 
			 
			
				
  | 
			 
			
				After I thought I was so careful watching numbers I forgot Scott took a 30 to 45 minute flight at OSH using the total gallons and cost so the numbers are actually a little better than what I originally posted.
 
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  |  
 
 
 
  
 _________________ 40936
 
RV-10 SB N801VR Flying
 
780 Hours
 
SuperSTOL 60 hours | 
			 
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