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#61
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![]() G.R. Patterson III wrote: Jerry Springer wrote: Is your name Jimmy???? I have not seen you contribute anything to this thread, did I miss your posts somewhere??? Stick it. This is a public forum. You want to communicate privately with Jimmy, use email. Until then, don't bitch if someone else opens up. George Patterson Great discoveries are not announced with "Eureka!". What's usually said is "Hummmmm... That's interesting...." Yes it is a public forum, and isn't wonderful that we each can say and believe what we want? Even you George are welcome to add your "Stick it" comment. :-) That really sheds new light on the subject at hand. I find your tag line interesting. Think about it..... Anyway it is Christmas I am going to celibrate with family. Each of you that think I am so wrong can have the last say on this. Marry Christmas or Happy Holidays, Jerry |
#62
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![]() Anyway it is Christmas I am going to celibrate with family. Each of you that think I am so wrong can have the last say on this. Marry Christmas or Happy Holidays, Jerry And Merry Christmas to you and your family Jerry. Best wishes, Jimmy |
#63
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![]() Jerry Springer wrote: Is your name Jimmy???? I have not seen you contribute anything to this thread, did I miss your posts somewhere??? Stick it. This is a public forum. You want to communicate privately with Jimmy, use email. Until then, don't bitch if someone else opens up. George Patterson Great discoveries are not announced with "Eureka!". What's usually said is "Hummmmm... That's interesting...." |
#64
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Let me add a bit.
In the early days of Jet A/C, the fuel was JP-1. We used it in the F/P-80 and T-33. If we had to land at a field that didn't have the JP-1 we could fill up with gasoline and use it to get to a field that had JP-1. We had to watch the TPT and not exceed the red line but the gas worked fine. We lost a little thrust using the gasoline vs JP-1 but just adjusted the legs to fit to the range with gasoline. Big John On Tue, 23 Dec 2003 22:55:18 +1300, Bruce Hamilton wrote: David Pears wrote: I though gas turbines (as used in aircraft engines) would run on just about any old liquid, as long as it has a hint of hydrocarbon in it? The problem is that turbine fuel ( effectively an aviation kerosine ) has to also satisfy several requirements, both with regard to engine performance and safety. The fundamental ones are flash point ( temperature at which the fuel will give off sufficient vapours to ignite if a flame is applied ) and freezing point ( engines tend to stop when fuel turns to sludge ). Avgas has suitably low freezing point, but the flash point is far lower than the fuel systems on a commercial Jet A1 fuelled airliner are designed to cope with. Military airliners often use a wide cut kerosine with a flash point well below airfield ambients. If a plane is carrying passengers, it's usually running on Jet A1, a narrow cut fuel with a flash point above most airfield ambient temperatures ( 38C ). Flash point is also the easiest method of detecting whether a kerosine has been contaminated by a gasoline. The 1997 explosion of the "empty" centre tank in TWA Flight 800, has reignited interest in fuel flammability issues. Kerosines tend to have more lubricity than gasolines ( higher sulphur and viscosity ) but high pressure hydrotreating and hydrocracking have made fuels "harder" ( less lubricity ), and NZ aviation authorities have convinced other countries to include a lubricity specification in DefStan 91-91 but, AFAIK, it's not yet in the more common ASTM D1655. Note that refractory elements ( silicon, calcium, potassium, vanadium etc ) will erode-deposit on turbine blades, and they are present in higher boiling fractions such as diesel ( which wouldn't pass the freezing point requirement - but is used on ship and power-station gas turbines ). Fuels for gas turbines tend to ensure such elements aren't present, even though falling out of the sky isn't an option, as overhauls are very expensive. There are a whole heap of other criteria for Jet fuels associated with cleanliness, corrosivity, combustion properties, stability and approved additives that mean than commercial aircraft tend to use a well defined narrow cut kerosine fraction. Bruce Hamilton |
#65
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ftB
ig John wrote in message . .. Let me add a bit. In the early days of Jet A/C, the fuel was JP-1. We used it in the F/P-80 and T-33. If we had to land at a field that didn't have the JP-1 we could fill up with gasoline and use it to get to a field that had JP-1. We had to watch the TPT and not exceed the red line but the gas worked fine. We lost a little thrust using the gasoline vs JP-1 but just adjusted the legs to fit to the range with gasoline. Big John On Tue, 23 Dec 2003 22:55:18 +1300, Bruce Hamilton wrote: David Pears wrote: I though gas turbines (as used in aircraft engines) would run on just about any old liquid, as long as it has a hint of hydrocarbon in it? The problem is that turbine fuel ( effectively an aviation kerosine ) has to also satisfy several requirements, both with regard to engine performance and safety. The fundamental ones are flash point ( temperature at which the fuel will give off sufficient vapours to ignite if a flame is applied ) and freezing point ( engines tend to stop when fuel turns to sludge ). Avgas has suitably low freezing point, but the flash point is far lower than the fuel systems on a commercial Jet A1 fuelled airliner are designed to cope with. Military airliners often use a wide cut kerosine with a flash point well below airfield ambients. If a plane is carrying passengers, it's usually running on Jet A1, a narrow cut fuel with a flash point above most airfield ambient temperatures ( 38C ). Flash point is also the easiest method of detecting whether a kerosine has been contaminated by a gasoline. The 1997 explosion of the "empty" centre tank in TWA Flight 800, has reignited interest in fuel flammability issues. Kerosines tend to have more lubricity than gasolines ( higher sulphur and viscosity ) but high pressure hydrotreating and hydrocracking have made fuels "harder" ( less lubricity ), and NZ aviation authorities have convinced other countries to include a lubricity specification in DefStan 91-91 but, AFAIK, it's not yet in the more common ASTM D1655. Note that refractory elements ( silicon, calcium, potassium, vanadium etc ) will erode-deposit on turbine blades, and they are present in higher boiling fractions such as diesel ( which wouldn't pass the freezing point requirement - but is used on ship and power-station gas turbines ). Fuels for gas turbines tend to ensure such elements aren't present, even though falling out of the sky isn't an option, as overhauls are very expensive. There are a whole heap of other criteria for Jet fuels associated with cleanliness, corrosivity, combustion properties, stability and approved additives that mean than commercial aircraft tend to use a well defined narrow cut kerosine fraction. Bruce Hamilton |
#66
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Bah. First I'd heard about this, not read much aviation press
recently. http://www.polarfirst.com/html/press.php?recno=4 I see the helicopter they were flying was a Bell 407. Jennifer's previous round the world record flights were all in an R-44, with "Q" (Quentin Smith) either as co-pilot (1996) or flying another helicopter (another R-44) alongside, with Colin Bodil flying his microlight (2000). http://www.earthrounders.com/other.html Polly Vacher is also on her way to circumnavigate the world via the two poles (having done it the "easy" way in 2001) in her Piper Dakota. http://www.worldwings.org/ http://www.earthrounders.com/singles.html Paul "BJ" wrote in message ... http://www.falklandnews.com/public/s...2549&source=12 "Following the reception of a distress call early this morning, a massive search for 63 year-old Jenny Murray and her co-pilot, Colin Bodil began and culminated in their successful rescue. |
#67
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Wonder if she/they will get the bill for the cost of the rescue and the cost
of removing the aircraft and containing any spills... Here in Michigan the state and the coast guard is getting stern about this with the ice fishermen and the snowmobilers... Stay out on the ice after a warning has been posted and have to be rescued and you will get a bill in the thousands of dollars... denny "Paul Sengupta" wrote in message ... Bah. First I'd heard about this, not read much aviation press recently. |
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