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  #71  
Old 05-22-2012, 02:56 PM
Hermanthegerman Hermanthegerman is offline
 
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Quote:
Originally Posted by tjo View Post
Diesel, on the other hand, has a relatively low vapor pressure, so the environment inside fuel tank is ripe for ignition with a nice mixture of fuel and oxygen available for the reaction.
wich is why we constantly see diesel powered cars and trucks blow up by the thousands

Quote:
Originally Posted by tjo View Post
The most public example of jet fuel igniting like this inside of an enclosed tank was the 747 that went down over Long Island. The cause was a shorted, sparking wire inside the fuel tank.

Tim
The jury is still out on that one as to the REAL reasons...
  #72  
Old 05-22-2012, 04:19 PM
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Default Be Nice!

Gentlemen,
this thread has taken a vector in a different direction from its original intent. As a moderator, I am getting an itchy finger to "moderate" this thread.

Please review Doug's Forum Rules before continuing this thread.

Thanks.
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Last edited by rv7boy : 05-22-2012 at 04:24 PM.
  #73  
Old 05-22-2012, 06:08 PM
sailvi767 sailvi767 is online now
 
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Quote:
Originally Posted by Hermanthegerman View Post
wich is why we constantly see diesel powered cars and trucks blow up by the thousands



The jury is still out on that one as to the REAL reasons...

If you have not read the actual investigation on the TWA flight you should take a look. I don't think the jury is out at all. The facts are self evident when you see the chain of events. It was the usual combination of many factors forming a long chain with the accident at the end. The good news is that the lesson learned caused many changes in procedures on similar aircraft and have without a doubt prevented 1 or more accidents caused by the same events.

George
  #74  
Old 05-22-2012, 07:28 PM
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Quote:
Originally Posted by Jconard View Post
Stress is caused by inertial force as pistons and other parts are accelerate or slowed. Inertial load or force or in other words the "stresses" increase at the square of speed, but linearly with force. Which means that if you double the mass of the objects you double the force, but if you double the speed or more accurately the rate of acceleration, you quadruple the force.
Reading this thread for this first time this got my attention. I wonder what the author is trying to say. Newton figured out that Force = Mass * Acceleration, so the statement
Quote:
if you double?the rate of acceleration, you quadruple the force
is not true.
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  #75  
Old 05-22-2012, 09:27 PM
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Read it again...

"Rate of acceleration" is not the same as "acceleration."

I'd have to dust off my old engineering books and think awhile to see if he is technically correct.

But IIRC Velocity has units of distance over time;
Acceleration has units of distance over time squared;
And Jerk has units of distance over time cubed.

I think he is speaking of "Jerk" here. (Please, everyone, no jokes about "Jerks" will be appreciated.) :-)
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Last edited by rv7boy : 05-22-2012 at 09:55 PM.
  #76  
Old 05-22-2012, 10:21 PM
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Buggsy2 Buggsy2 is offline
 
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Yes, rate of [change] of acceleration with respect to time is the jerk. But given that he equates speed with jerk "if you double the speed or more accurately the rate of acceleration" I doubt he carefully selected jerk in his statement.

Too bad, since I think the writer is trying to say something of value and I wanted to follow it. Not trying to nitpick or embarrass him, rather would like a clearer explanation.
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  #77  
Old 05-23-2012, 08:05 AM
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Quote:
Originally Posted by Hermanthegerman View Post
Only a few weeks back the founder of the LEKI company here in germany survived the crash of his Extra, but was burned alive in the ensuing fire. His copilot tried to get him out but was driven away by the flames.

That fire would not have happened with diesel fuel.

You might want to ask his wife what she thinks of AVGAS


The whole ACCIDENT would not have happened, since it involved mixing up the mixture lever with another one.
Over 60 years ago there were already single lever engine operations on complex high performance engines.

Lycoming and the likes are as adapt to their environment as the Dodo was...
Diesel and jet fuel burn too. Ever seen what happens when a jet crashes? I saw a diesel bus on fire last year too. Diesel is fuel, designed to burn and as such, dangerous as well when an ignition source is present.
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  #78  
Old 05-24-2012, 05:15 AM
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RV10inOz RV10inOz is offline
 
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A properly set up conforming Lyc/TCM when run efficiently is about as good as it gets. The HP/ NMPG etc for the task are pretty hard to beat.

No need for multi valve, multi cam, EFI etc etc.

Simple as that. Do the research and the maths.
  #79  
Old 05-24-2012, 07:18 AM
Captain Avgas Captain Avgas is offline
 
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Quote:
Originally Posted by Hermanthegerman View Post
Lycoming and the likes are as adapt to their environment as the Dodo was...
Well Herman, the Dodo was actually a bird that was so overweight that it couldn't get off the ground which is what ultimately led to its extinction.

So in that regard it would appear that all of the obese GA aero-diesel engines that have appeared and then promptly become extinct in recent decades have more in common with the Dodo than the excellent power to weight ratio Lycoming which is still very much alive and thriving.
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  #80  
Old 05-24-2012, 08:27 AM
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Quote:
Originally Posted by rv7boy View Post
Gentlemen,
this thread has taken a vector in a different direction from its original intent.
...in 2008.
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