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On Wed, 30 May 2007 15:10:29 GMT, Jerry Wass
wrote: Don't like to beat a dead horse, but-- As C.S. Nixon said--"let me make myself perfectly clear" I agree that a gallon of Mogas has more btu's than a gallon of Avgas The main reason being--1 gal mogas= 7.422 lbs. 1 gal avgas= 6.978 lbs. Q.E.D. Per Wikipedia, and my friends who do weight/balance calcs, the avgasd number above is alittle, like 18%, off ... Avgas has a density of 6.02 lb/US gallon at 15 °C, or 0.72 kg/l, and this density is commonly used for weight and balance computation. Density increases to 6.40 lb/US gallon at -40 °C, and decreases by about 0.5% per 5 °C increase in temperature.[3] [3] is # ^ MacDonald, Sandy A. F.; Isabel L. Peppler [1941] (2004). "Chapter 10. Airmanship", From The Ground Up, Millennium Edition, Ottawa, Ontario, Canada: Aviation Publishers Co. Limited, pp. 265, 261. ISBN 0-9680390-5-7. AirBP says "AVGAS 100LL: Aviation Gasoline for Reciprocating Engines with lower maximum lead content. Color: Blue. Flash point: Below 0 degrees F. API gravity: 64-7. Relative density: .6582-.7238". Water is likely the density of 1.000, and is about 8.34 lb/gal suggesting the 6 lb/gal is a pretty good number. I'd like to know the source for your 6.978 ... |
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GeorgeB wrote:
On Wed, 30 May 2007 15:10:29 GMT, Jerry Wass wrote: Don't like to beat a dead horse, but-- As C.S. Nixon said--"let me make myself perfectly clear" I agree that a gallon of Mogas has more btu's than a gallon of Avgas The main reason being--1 gal mogas= 7.422 lbs. 1 gal avgas= 6.978 lbs. Q.E.D. Per Wikipedia, and my friends who do weight/balance calcs, the avgasd number above is alittle, like 18%, off ... Avgas has a density of 6.02 lb/US gallon at 15 °C, or 0.72 kg/l, and this density is commonly used for weight and balance computation. Density increases to 6.40 lb/US gallon at -40 °C, and decreases by about 0.5% per 5 °C increase in temperature.[3] [3] is # ^ MacDonald, Sandy A. F.; Isabel L. Peppler [1941] (2004). "Chapter 10. Airmanship", From The Ground Up, Millennium Edition, Ottawa, Ontario, Canada: Aviation Publishers Co. Limited, pp. 265, 261. ISBN 0-9680390-5-7. AirBP says "AVGAS 100LL: Aviation Gasoline for Reciprocating Engines with lower maximum lead content. Color: Blue. Flash point: Below 0 degrees F. API gravity: 64-7. Relative density: .6582-.7238". Water is likely the density of 1.000, and is about 8.34 lb/gal suggesting the 6 lb/gal is a pretty good number. I'd like to know the source for your 6.978 ... My Sources a a 5 gal can of Avgas bought for break-in purposes on my rebuilt engine--about two weeks ago, and kept in a S.Steel can of the variety used for holding Coke/Pepsi syrup at vending booths.--air tight. good for 125 psi(has to hold the CO2 pressure) a 5 gal jug of Mogas bought a week ago for my lawnmower. a 250 CC graduated Lab-type beaker, & a metric balance type scale accurate to 0.1 gm. The Avgas weighed 168.3 gms/250cc---The Mogas weighed 179.0gm/250cc---- Please let me know If I made any mistakes in the conversion----If not, I'll re-weigh two more samples tomorrow.. |
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On Thu, 31 May 2007 00:25:09 GMT, Jerry Wass
wrote: GeorgeB wrote: On Wed, 30 May 2007 15:10:29 GMT, Jerry Wass wrote: Don't like to beat a dead horse, but-- As C.S. Nixon said--"let me make myself perfectly clear" I agree that a gallon of Mogas has more btu's than a gallon of Avgas The main reason being--1 gal mogas= 7.422 lbs. 1 gal avgas= 6.978 lbs. Q.E.D. Per Wikipedia, and my friends who do weight/balance calcs, the avgasd number above is alittle, like 18%, off ... Avgas has a density of 6.02 lb/US gallon at 15 °C, or 0.72 kg/l, and this density is commonly used for weight and balance computation. Density increases to 6.40 lb/US gallon at -40 °C, and decreases by about 0.5% per 5 °C increase in temperature.[3] [3] is # ^ MacDonald, Sandy A. F.; Isabel L. Peppler [1941] (2004). "Chapter 10. Airmanship", From The Ground Up, Millennium Edition, Ottawa, Ontario, Canada: Aviation Publishers Co. Limited, pp. 265, 261. ISBN 0-9680390-5-7. AirBP says "AVGAS 100LL: Aviation Gasoline for Reciprocating Engines with lower maximum lead content. Color: Blue. Flash point: Below 0 degrees F. API gravity: 64-7. Relative density: .6582-.7238". Water is likely the density of 1.000, and is about 8.34 lb/gal suggesting the 6 lb/gal is a pretty good number. I'd like to know the source for your 6.978 ... My Sources a a 5 gal can of Avgas bought for break-in purposes on my rebuilt engine--about two weeks ago, and kept in a S.Steel can of the variety used for holding Coke/Pepsi syrup at vending booths.--air tight. good for 125 psi(has to hold the CO2 pressure) a 5 gal jug of Mogas bought a week ago for my lawnmower. a 250 CC graduated Lab-type beaker, & a metric balance type scale accurate to 0.1 gm. The Avgas weighed 168.3 gms/250cc---The Mogas weighed 179.0gm/250cc---- Please let me know If I made any mistakes in the conversion----If not, I'll re-weigh two more samples tomorrow.. Sounds right to me. SG has an effect on the energy content, but it is NOT an indicator of octane. MoGas has a higher energy density than AvGas (generally). -- Posted via a free Usenet account from http://www.teranews.com |
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On Thu, 31 May 2007 00:25:09 GMT, Jerry Wass
wrote: The main reason being--1 gal mogas= 7.422 lbs. 1 gal avgas= 6.978 lbs. Avgas has a density of 6.02 lb/US gallon at 15 °C, or 0.72 kg/l, and The Avgas weighed 168.3 gms/250cc---The Mogas weighed 179.0gm/250cc---- Please let me know If I made any mistakes in the conversion----If not, I'll re-weigh two more samples tomorrow.. Plugging your avgas numbers into my conversion software, I get 0.371 lb / 0.066 gal for your measurements ... which my calculator gives as 5.62 lb.gal. I didn't run the mogas. One of us has bad conversion data, maybe both of us. George |
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GeorgeB wrote:
On Thu, 31 May 2007 00:25:09 GMT, Jerry Wass wrote: The main reason being--1 gal mogas= 7.422 lbs. 1 gal avgas= 6.978 lbs. Avgas has a density of 6.02 lb/US gallon at 15 °C, or 0.72 kg/l, and The Avgas weighed 168.3 gms/250cc---The Mogas weighed 179.0gm/250cc---- Please let me know If I made any mistakes in the conversion----If not, I'll re-weigh two more samples tomorrow.. Plugging your avgas numbers into my conversion software, I get 0.371 lb / 0.066 gal for your measurements ... which my calculator gives as 5.62 lb.gal. I didn't run the mogas. One of us has bad conversion data, maybe both of us. George Doing the simplest conversion---168.3/250.0--= sp.gr.of 0.6732.. 0.6732X 8.34(#/gal for h2o)= 5.614 #/gal for Avgas--agreeing with you--but isn't right---I'm gonna weigh things again--might have been off on my tare weight. Jerry |
#6
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![]() Jerry Wass wrote: Doing the simplest conversion---168.3/250.0--= sp.gr.of 0.6732.. 0.6732X 8.34(#/gal for h2o)= 5.614 #/gal for Avgas--agreeing with you--but isn't right---I'm gonna weigh things again--might have been off on my tare weight. Jerry -=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=- I don't keep avgas at my house. However.... Weighing 250 cc of 60 degree F. mogas = 190 grams Specific gravity = 190/250cc = 0.76 0.76 x 8.34 = 6.3384.... MOGAS = 6.3384 lb/gal @ 60 degrees F. More than close enough for GW Bush gov't work! Barnyard BOb - definitely beating YOUR dead horse 8-) |
#7
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On Thu, 31 May 2007 10:56:21 -0500, Barnyard BOb
wrote: Jerry Wass wrote: Doing the simplest conversion---168.3/250.0--= sp.gr.of 0.6732.. 0.6732X 8.34(#/gal for h2o)= 5.614 #/gal for Avgas--agreeing with you--but isn't right---I'm gonna weigh things again--might have been off on my tare weight. Jerry -=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=- I don't keep avgas at my house. However.... Weighing 250 cc of 60 degree F. mogas = 190 grams Specific gravity = 190/250cc = 0.76 0.76 x 8.34 = 6.3384.... MOGAS = 6.3384 lb/gal @ 60 degrees F. More than close enough for GW Bush gov't work! A more relevant number is the BTUs per gallon which translaes into MPG for a given engine. Automotive gas in California is about 111,500 BTU while E85 is about 81,000, or 72% Straight Ethenol is roughtly 60% or 66,600 BTU. Alcohol costs more while giving much less energy and MPG. IOW just going from straight gas to E85 a trip that takes 50 gallons of gas will take at least 69.5 gallons of E85. Given todays car gas prices of basically $3.20 per gallon (it's near $3.50 in michigan) if we take that 50 gallons of gas for a trip at $3.50 it's 175 USD. Given the same price for E85 (which is actually more expensive) we come up with $243.25, or an extra $68.25 for the same trip using E85. Alternative fuels are in general more expensive to use or implement than gas. For those fuels to become viable alternatives the cost of gas is going ot need to go to at least $3.50 a gallon and stay there. Except for small scale implementation, Hydrogen is much more expensive. I spent some time with a consulatant a couple weeks back. His conclusion for me to go a combination of active and passive solar power would easily run bet ween $30,000 and $50,000 for this small home. Yes, I could sell power back to the power company, BUT our rates are about 8 cents per KWH whichmakes for a very long pay back if I don't have to purchase any power. Add to that, maintenance on the syatem and it really starts to get expensive. |
#8
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![]() "Roger (K8RI)" wrote: MOGAS = 6.3384 lb/gal @ 60 degrees F. More than close enough for GW Bush gov't work! A more relevant number is the BTUs per gallon which translaes into MPG for a given engine. -=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=- Roger, You are very, very late to this party. Btu/gal is not only old news, if you follow this thread back.... but of no interest to the 'victims' beating this horse dead! Sorry. 8-) - Barnyard Bob - lord luva duck |
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Thread | Thread Starter | Forum | Replies | Last Post |
Fuel prices--BTU's per gal. | George | Home Built | 3 | May 30th 07 09:25 PM |
Fuel prices--BTU's per gal. | Jerry Wass | Home Built | 18 | May 30th 07 11:15 AM |
Fuel Prices | Ross Richardson | Owning | 60 | September 30th 05 02:06 AM |
Fuel Prices | ~R | Rotorcraft | 0 | September 10th 05 03:56 PM |
Fuel Prices | S Green | Piloting | 0 | May 9th 04 09:47 PM |