The Sparrow Strainers are draggy and slow our
planes down. There must be an alternative. Every time a
speed specialist looks at the the sparrow strainers they
go "WTF"?
So, let's start at the beginning. Why are there in
the first place?
As I understand it, they are an aerodynamic trim
designed to counteract the high pressure on the bottom
of the canard elevator. Air wants to push the TE of the
elevator up, causing the plane to dive, so the sparrow
strainers help by pushing it back down.
Is this logic correct?
So, what would be a drag-free alternative? Well, I
suppose one could increase the spring tension already
used for the control stick. Why didn't QAC
do something like that? Maybe it would increase the
stick forces. Just guessing but when they first flew
flew the new LS-1 airfoil, they probably found they
needed an extraordinary amount of nose up trim.
Followed by going with the cheapest fix - add sparrow
strainers.
Another issue with using internal trim, is you are
applying a constant torque to the joint there the
elevator bellcrank slips into the elevator torque tube.
Maybe it's not a big deal, bit it's there.
This is all supposition. Is anyone privy to the real
story?
So, all of you aerodynamic
tinkerers, what could be a viable way to eliminate the
sparrow strainers?
Thanks for reading.
Sam