Sender: <marv@lancaironline.net> (Marvin Kaye)
To: lml
Date: Wed, 05 Jun 2002 13:43:35 -0400
Message-ID: <redirect-1283182@logan.com>
From: RWolf99@aol.com
Subject: Re: Left Throttle, Right Stick
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Okay, guys, here's a relatively simple way to implement a left hand throttle 
in a 320/360.  I have this half done, then decided to shelve the idea, but 
then saw a variant of the idea implemented in Bart Bartholomew's 320 (N320BB) 
for which Chuck Brenner provided some builder support.

First thing to ask is whether the left had throttle will be the only control 
(as it is in Bart's airplane) or will it be a secondary control, with the 
primary still in the center (as it will be on mine if I decide to finish the 
installation).  

If it is the only control, you need to have a friction lock there and 
probably want all three controls (prop, mixture and throttle) together by 
your left knee.  If it is a secondary control then you DON'T want the 
friction lock (the one on the primary knob is enough) and you probably only 
need the throttle control duplicated on the left side.  Including all of them 
makes for a bulky installation (but Bart says it doesn't get in the way).

Go to Van's Aircraft and buy a throttle quadrant.  Either use it as supplied 
(three levers plus friction lock) or strip it down to a thinner one-lever 
quadrant and remove the friction lock (as I have).  Glass a wooden or 
phenolic block to the left hand inner wall of the cockpit to bolt the 
quadrant onto.

If it's your only control, just run the cables normally.  (Bart actually has 
pushrods.)

If it's your secondary control, run a sleeved control cable (just like a 
throttle cable but without the knob on the end) from the quadrant forward to 
the firewall, then along the firewall and back along the pilot's side of the 
nose gear tunnel so that it's in a big U shape.  Mount a metal idler arm with 
a central pivot point to the side of the nose gear tunnel.  Attach the idler 
arm to the nose gear tunnel in a similar manner to the aileron pushrod idler 
that's attached to the main spar in the wheel well (or use a Click-Bond 
stud).  Make sure there's a bearing in the attachment, just like the aileron 
pushrod idler.  Attach the end of the cable to one end of the idler arm.  
Now, take your primary throttle control cable, throw it away, and buy another 
identical one that's really short.  Attach the forward end of this cable to 
the other end of the idler arm.

Why the idler arm?  When you push the primary throttle cable in, the other 
end moves towards the front of the plane.  When you push the secondary 
left-hand throttle lever forward, the other end of its cable moves towards 
the back of the plane (because of the U shaped bend).  The idler arm, 
however, moves the same way regardless of which control is used.

Now that you've got an idler arm that wiggles back and forth, you need a 
third cable which goes from one end of the idler to the engine.  This is the 
cable that penetrates the firewall.  Attach this to the end that the primary 
control goes to, since that's the end that goes forward when you want to go 
faster.  If you're clever, you'll attach it to the same hole that the primary 
cable connects to, such that if the idler arm totally fails (as in rips off 
of the nose gear tunnel wall), you still have a viable connection to the 
engine from the primary control.

Wish I had pictures, but I haven't built it yet.  I may not, since all my 
pilot buddies say that I'll adapt to a left hand stick in less than an hour.  
After all, I fly yoke-equipped airplanes with my left hand already....

- Rob Wolf