The Vernisse Coupling for Tandem Engines: A Brief Note on the Ingenious Constant‐Torque Joint Developed by the Arsenal de l'Aeronautique

IN the articles on the VB‐10 tandem‐engined single‐seater and the Arsenal de l'Aéronautique the Vernisse coupling has been mentioned. The desirability of a constant‐torque coupling was realized as long ago as 1937 and work was begun on the design in 1939. The idea was to develop a coupling primarily to enable engines to be mounted in tandem so that they would drive co‐axial airscrews, but also to provide a shaft joint that would take up structural deflexions for extension drives of single engines.