hopper theory & practice

[John Ferrell]

I have been a skeptic as well. However, the ducted fan and helicopter folks have been advocating them for a long time, there must be some merit. On the other hand, if it won't work without a header tank, I feel you are too close to the edge of not working at all. 

John Ferrell    
http://DixieNC.US

  ----- Original Message ----- 
  From: ronlock at comcast.net 
  To: discussion at nsrca.org ; discussion at nsrca.org 
  Cc: Jerry Budd 
  Sent: Friday, August 13, 2004 8:34 AM
  Subject: Re: hopper theory & practice


  Ive been a hopper tank diss-believer for years.  I also wonder why many continue to report benefits.  What's responsible for the benefit?

  I'm in agreement with Nat, and what "I think" Jerry has said regarding the fuel system with a FULL hopper tank being a column of fluid, and the hopper would have no benefit.

  Maybe hopper serves to eliminate foaming and bubbles?  Do I understand heli pilots use hoppers for that reason?

  In practice do we usually have some air in the hopper?   Or do we usually have a hopper tank that is flexible?   Might we be drawing from the hopper without replenishing from the main tank during a vertical?    Then the hopper gets replenished during level lines?

  Still wondering, Ron Lockhart

    -------------- Original message -------------- 

    > >Matt, 
    > >With or without the hopper tank we still have a solid column of 
    > >incompressible fluid for gravity and G's to play its tricks on. I 
    > >contend if it runs ok with the hopper it will run just as well 
    > >without. Nat 
    > 
    > Nat, 
    > 
    > While not exactly accurate as stated, your point is well taken. Your 
    > hypothesis has some merit when the tank is full, but it falls short 
    > anytime else (which is most of the flight). Adding just a small 
    > amount of air causes the system to become compressible (just like the 
    > brakes on your car). 
    > 
    > Jerry 
    > -- 
    > ___________ 
    > Jerry Budd 
    > mailto:jbudd at qnet.com 
    > ===================================== 
    > # To be removed from this list, go to http://www.nsrca.org/discussionA.htm 
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    > 
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