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Date: Wed, 04 May 2005 20:53:02 -0500
From: Jim Sower <canarder@frontiernet.net>
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To: Rotary motors in aircraft <flyrotary@lancaironline.net>
Subject: Re: [FlyRotary] Re: Circuit breaker article( redundancy power)
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<... When you route all 3 lines in the same path ...>
I know.  That's the difference between a "backup" system and a 
"redundant" system.

In the mid '60s, the Air Force spent millions re-routing the backup 
hydraulic system of the F-105 to the other side of the airplane from the 
primary.  The Navy wasn't so astute.  ALL of the hydraulics of the F4 
came together like in one giant manifold in the center of the belly 
(interestingly, right at the aim point :o) where one round would make 
you ballistic.

Great engineering ... Jim S.


David Staten wrote:

> Yea.. I believe it was an L-1011.. but the problem was the uncontained 
> engine failure caused the breach of all 3 engine driven hydraulic 
> systems. When you route all 3 lines in the same path.. well..
>  
> There IS a limit to the amount of redundancy you can have.. and how 
> much you can "armor" fluid lines and cable paths..
>
> You can put enough redundant and protected systems into your craft 
> that it would be named "The Dodo Bird" because it would be too damn 
> heavy to fly.
>  
> Dave
>
> Jim Sower wrote:
>
>> <... You do not have to have more than one level of redundancy to 
>> basically eliminate any chance of total failure of the system with 
>> failures in the 1000 hour range ...>
>> You might want to talk to the crew of that 757 or L1011 or whatever 
>> it was that crashed in Souix City(?) a few years back because it lost 
>> ONE of THREE engines and immediately went ballistic.
>>
>> The devil made me say that :o) ... Jim S.
>>
>>
>> WALTER B KERR wrote:
>>
>>>  Ian
>>> I would think that in the case of airliners they have so many 
>>> redundant systems that if one goes down they have two or three 
>>> others to continue with, so there is no emergency situation in there 
>>> case.
>>> Georges
>>> -------------------------------------------------------------------------
>>>  
>>> You do not have to have more than one level of redundancy to 
>>> basically eliminate any chance of total failure of the system with 
>>> failures in the 1000 hour range such as fuses as long as the pilot 
>>> has time to try the backup system? I will take reduncancy ever day 
>>> of the week compared to a single CB circuit albeit it I have 
>>> parallel master switch circuit breaker's but I do not intend to 
>>> reset one as long as the other is working :>)
>>>  
>>> I know we are not changing anyone's veiws on CB vs fuses, but it has 
>>> been an interesting dialogue.
>>>  
>>> Bernie
>>>  
>>>
>>>>  Homepage:  http://www.flyrotary.com/
>>
>>>>  Archive:   http://lancaironline.net/lists/flyrotary/List.html
>>
>>  
>>
>>>  Homepage:  http://www.flyrotary.com/
>
>>>  Archive:   http://lancaironline.net/lists/flyrotary/List.html
>
>
>  
>