Chief mechanic for the Precious Metal air race team, Brenden Burns doing a high power night ground run with boost to 40 inches of Mercury in preparation for the 2014 Reno Air Race eventually placing 3rd in class only to be disqualified in a controversial decision.


A typical P-51D Mustang would have been powered by the venerable Rolls-Royce Merlin V-12 and pumped out an impressive 1,600 horsepower. The Griffon was the last of Rolls-Royce’s line of V-12s, was used on later variants of the Supermarine Spitfire and raised power output to 2,340 hp. The increased torque would cause the plane to swerve violently on takeoff. A contra-rotating propellor was developed to eliminate this torque effect, but unfortunately the gearbox associated with driving two props in opposite directions was so complex that is never saw official operations with the Spitfire.

Precious Metal is unofficially labeled an XR-51D, a one of a kind, purpose built, P-51 Mustang with a 3,200 hp Rolls Royce Griffon engine and contra-rotating props. You can easily see in this night video the glowing probes of the exhaust gas temperature sensors (EGT). Exhaust temps are generally used to monitor fuel ratio in each cylinder. Hotter temps might be due to lean mixture or vice versa.

Chris is a pilot who loves airplanes, cars, and motorcycles. His writing has been seen on Jalopnik. Contact him with questions or comments via twitter or email.

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