Why the SR-71 Blackbird’s Tires Were Silver

Capable of cruising at Mach 3, or roughly 2,000 mph, the SR-71 Blackbird was designed to fly higher, faster, and farther than anything else in the sky. But while most know it for its titanium skin and stealthy black paint, even its tires were engineering marvels—so unusual they came out silver instead of black.

Built for Fire and Friction

At such extreme speeds, the Blackbird’s airframe could heat up to 400 degrees Fahrenheit, and the cockpit windshield sometimes reached 650 degrees. Landing a jet that hot put massive stress on the tires. To survive, BFGoodrich infused them with powdered aluminum, giving the rubber a silvery sheen and a much higher flash point. In other words, they wouldn’t burst into flames when they hit the runway.

Extreme Pressure, Extreme Design

Each rear wheel carried three specialized tires inflated to a staggering 415 psi—more than ten times the pressure in your car’s tires. To further reduce fire risk, they were filled with pure nitrogen instead of air. Even so, they only lasted about 15 full-stop landings. Pilots often took off with half a fuel load, then refueled in the air, just to reduce strain on the wheels.

A Pricey Piece of Rubber

Those short-lived tires weren’t cheap. Each one cost about $2,300 in the 1960s—tens of thousands in today’s money. Former Blackbird pilot Colonel Ken Collins recalled how the wear and tear came mostly at takeoff, when the aircraft’s sheer weight and speed hit the tires hardest.

Engineering at Every Level

From its titanium frame to its radar-absorbing paint, every part of the SR-71 was designed to survive where no other jet could. Even its landing gear spoke to the extremes of speed and altitude it operated in. The silver tires are a reminder that nothing on the Blackbird was ordinary—it was innovation pushed to the very edge of possibility.