Push-Pull Controls

Vernier-Assist™

McFarlane’s patented Vernier-Assist™ offers the pilot precision control of the engine, unlike anything else on the market! The Vernier-Assist assembly operates on friction alone by simply turning the knob, with no threads or locking balls/pins. It also allows for normal coarse movement by pushing in or out on the knob. – Unlike standard threaded vernier controls, this design cannot be jammed. The friction control provides smoothness and precision when operating the throttle and a friction lock secures the control in position, but it can be easily overridden in the case of an emergency. It is now FAA-PMA approved and SAFE!

US Patent No. 8,485,057 B1

Metal Construction

Unlike the controls of our competitors that use plastic, McFarlane control fittings and components are made from stainless steel, plated steel, anodized aluminum, and brass. 

Our Vernier control locking devices are precision formed and heat treated in critical wear areas.

A Superior Conduit System

Our controls have low-friction smoothness and flexibility, even when routed with multiple tight bends. Our conduits are made from carbon steel wire, specially formed for increased strength and smooth inside diameter. Two of these wires are coiled in tandem for increased tensile strength. A Teflon jacket extruded over the coiled housing provides additional strength and wear-resistance. A virgin Teflon® liner in the center of the conduit reduces friction and ensures reliable operation.

Knobs Make a Difference

Our “pilot friendly” knobs are all compression molded from a reinforced aluminum or phenolic. Unlike the soft injection molded knobs of our competitors, our knobs are hard and thermally stable. They're powder coated, scratch-resistant, and do not deteriorate. McFarlane knobs meet the latest F.A.R. requirements for shape and color.

Vibration Dampening Features

Our metal swivel joints have a unique Viton® rubber vibration dampening sleeve with a spring load system that dampens engine induced vibration in the push rod guide tube and metal swivel joint. Molded Viton® boots are also used on the push rod guides to seal out contaminates. The Viton® rubber withstands the high temperature of the engine environment while resisting degradation from oil and solvents. This system drastically reduces the wear that leads to premature control failure.

Special Lubrication

McFarlane controls have a special lifetime lubrication applied to critical sliding surfaces, made from a molybdenum disulfide and Teflon® based lubricant with a synthetic grease base. Our lubricant will reduce friction and prevent galling and contamination locking of the control components from -70 deg F to over 1000 deg F.

Consistent Quality

The assembly of McFarlane engine controls is interrupted many times for inspections of all critical elements to ensure only the highest quality controls are produced. Each inner wire swage, each push rod, each conduit fitting and terminal is inspected by our assembly team. As a further measure of quality, a second inspector also checks each critical detail to make sure only controls of the highest quality pass inspection. Attention is given to every detail at McFarlane Aviation. For instance, we verify the torque required to operate every vernier control to ensure it operates properly and has that smooth feel our customers have come to expect.

Tough in any Environment

The McFarlane controls have an outstanding performance and reliability record in all environments; we test them in the harshest environments to ensure they will provide a long and reliable service life. Bush pilots prefer our controls because they work freely at 50 deg below zero and have proven solidarity in harsh salt-water. Temperatures approaching the melting point of the steel components cannot stop McFarlane controls from functioning.

Time Tested

With over 25 years of experience building aircraft engine controls and with thousands of units in airplanes flying on every continent (yes, even Antarctica), McFarlane controls are universally recognized for their high quality products and proven track record.

Recommended Service Life

Considering the operating environment and criticalness of engine controls, our maximum recommended in-service time for McFarlane engine controls is equal to the maximum time between engine overhauls, as recommended by the engine manufacturer.