 
			
				December 8th 08, 06:31 PM
			
			
			
posted to rec.aviation.ifr
		
  
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				 This is why you should never trust your fuel gages
			 
			 
			
		
		
		
		
Mike wrote:  
 "Dale Scroggins"  wrote in message  
 ... 
 
 "Mike" nospam @ aol.com wrote in message  
 ... 
 "Dale Scroggins"  wrote in message  
 ... 
 
 "Mike" nospam @ aol.com wrote in message  
 ... 
 "Ron Garret"  wrote in message  
 ... 
 http://ronsvideos.fliggo.com/video/uIgc0dP9 
 
 This video was shot in a Cessna 206 taking us to a game reserve in  
 South 
 Africa.  Watch the fuel gage in the upper right corner. 
 
 This is typical for a Cessna and a few others where the fuel gauge  
 uses the same technology as a toilet tank float. 
 
 A fuel totalizer is a very nice thing to have. 
 
 Float-type sending units are, in fact, simpler than toilet tank  
 float valves, and more reliable.  They work reliably for decades.   
 However, many have been in service nearly forty years.  Eventually  
 the resistance winding will develop spots where the wiper doesn't  
 make good contact, and the gauge (U.S.) or gage (Brit.) will  
 fluctuate wildly for a few minutes, until fuel is burned off and the  
 wiper moves to a new location, then the gauge works normally again.   
 Simple and relatively simple to fix. 
 
 If what you say is true, why do quite a few relatively new planes  
 exhibit the same symptoms? 
 
 
 Do you believe fuel totalizers are more reliable?  Or capacitance  
 systems? Do you trust totalizers totally? 
 
 I've flown lots of planes with totalizers and never seen a failure.   
 I've also seen lots of failures and gross errors in float type  
 systems (new and old), so in my experience, yes they are more reliable. 
 
 As far as your last question it appears to be argumentative.  I could  
 just as easily ask you if you trust the standard Cessna fuel gauge  
 totally, but neither really deserves an answer. 
 I doubt my experiences are typical.  Most of the fuel quantity and  
 totalizer systems I saw over thirty years weren't operating correctly,  
 and I was being paid to repair them.  Age makes most indicating  
 systems untrustworthy. Having multiple systems is good, if they aren't  
 interdependent. 
  
 Agreed, and the best way to check them is simply to stick the tanks both  
 before and after a flight. 
  
 Even float rods on Piper Cubs and others hang occasional, or the  
 floats saturate and sink.  Direct-reading sight tubes are probably   
 the most reliable indicators, but even those can become difficult to  
 read with age. 
 
 I don't trust any fuel indication system. 
  
 There is one fuel indication system that's reasonably accurate, and that  
 is the prop which quits turning when you run out.  Where many people get  
 into trouble is they DON'T trust their fuel indication system until the  
 aforementioned one indicates zero.  I use mine to cross check my flight  
 planning, and if they don't agree it's time to do something different.
I like my engine performance tables and a stop watch, Pretty accurate.
 
-- 
 
Regards, Ross 
C-172F 180HP 
KSWI
  
		
	
		
		
		
		
		
	
		 
			
 
			
			
			
				 
            
			
			
            
            
                
			
			
		 
		
	
	
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