Vernier-Assist Mixture Controls

Vernier-Assist Mixture Controls

McFarlane invents a new type of vernier engine control
This brand new type of control has all the fine adjustment benefits of an old style push-button release vernier control, with the simplicity, responsiveness, and jam-proof safety of a friction lock control.


These light weight controls use a patented roller action and do not use a positive lock thread engagement. Coarse adjustments are made by pushing the knob inwards or pulling the knob outwards. Fine adjustments are made by rotating the knob clockwise or counterclockwise. For extreme conduit routing or heavy carburetor load installation, slight inward or outward assist pressure could be required during rotation.


We currently offer these new controls for use on non-certified aircraft only. However, we plan to obtain FAA-PMA approval to offer the new Vernier-Assist mechanism as an option on many of our currently approved controls for Cessna and Piper, as well as our popular MC600 universal mixture control.


  • Light weight and compact behind the dash
  • Good hand space around the knob 
  • Safer - Our roller action cannot jam
  • US Patent No. US 8,485,057 B1
  • Vernier-Assist Assembly Video


MCMV Mixture Series:
Vernier action with only a 3/8" panel hole!

The new Vernier-Assist mixture control offers vernier action in a light weight, compact package. It is a drop in replacement for many existing non-vernier mixture controls because it requires a 3/8" panel hole. It also only extends about 3.5 inches behind the dash making it ideal for aircraft with tight space constraints. Available in a variety of standard lengths or can be custom fabricated to your unique requirements.  


Mixture Control Specifications 

Installation Instructions 


Mixture Control with 0.061" diameter solid wire end:
Order part number MCMV0241-LLL (knob included) or MCVA0241-03-LLL (without knob).

  • LLL is the length in inches
  • Choose control length 048, 072, or 120