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Throttle Mod

          I never have liked the push pull throttles that are common in Cessnas and others.

           There is a reason you only see throttle levers in large aircraft.

 So I designed a throttle lever system.

Here is the design I made on Delta Cad for the throttles.  The basic design philosophy is to give about 100 mm of throttle movement.  I ended up with about that and then the holes in the throttle are providing about 34 mm of movement. 

 
The important dimension here is the 63 (62.95) which clears the top supports

This had to change because of a clearance problem  See Inst Panel 2

 
This then is transmitted with a push rod to the firewall where it goes into a bellcrank to increase the movement for the 63 mm required at the throttle.  It worked out to just double the arm.

This had to change because of a clearance problem  See Inst Panel 2

 

 
Now that I have the engine I can find out how much throw in needed for the throttle

This had to change because of a clearance problem  See Inst Panel 2

 
Subtracting you get about 63mm.  I considered not using the extension.  This would mean less deflection in the throttle mixer.  But after talking to Jabiru.  It is hard to find a good connection with out it.  So I decided to leave it.

 
Here is the Throttle quadrant.

 
I have a nylon piece capturing the bolt that the lever pivots on

 
View of the nylon that captures the bolt for the pivot point and throttle friction adjustment

 
Here you can see the inards of the quadrant.  I used.  The nylon parts are from Lowes

 
For the push rod I used "03-35400-3 6061T6 TUBE 5/16X.058" from Spruce.  I then tapped it with a 1/4 28 tap.

 
I then used a MS21252-5RS TURNBUCKLE and AN394-19 CLEVIS PIN  to form the push rod.

 
Here is a close up of the block I used for the torque bar and bellcrank

 
The Torque bar is from 1/4 bar with welded arms.  The center is then connected to the Boden cable through the firewall.  Approximately where the carb is located

 
Another view of the arrangement and how it hooks up to the copilot throttle

 
I was a little concerned about the proximity of the throttle arm to the rudder pedal.  Here is a shoe with idle throttle an neutral rudder

 
This is the worse case.  Full left rudder and idle throttle.  Still have 1 inch of clearance.   There will also be a cable going back to the rudder which will keep your foot from moving to the left.  I think it will work ok.

This had to change because of a clearance problem.  I originally had the rudders back a little more than I like.  So when I moved them forward I had a clearance problem.  See Inst Panel 2

 
A close up of the arm

 
Here is the Boden cable penetrating the firewall

 
Here is the throttle win the idle position.  You can also see the throttle friction knob at the bottom.

 
This is probably the most important position.  Full throttle.  What I am planning is to have the Flaps, Carb heat, and fuel boost pump switches located above the vent.  This way when doing a go around, touch and go, or take off your fingers and move this controls.

 
Here is a view from the top.  You can see the spacers that I put to move it out a little bit and the nylon guides.  The nuts are temporary.

 

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