Inside The Most MECHANICALLY STRESSED Piston Airliner Ever Built

The Boeing 377 Stratocruiser gave passengers a cocktail bar, sleeping berths, and a spiral staircase at 25,000 feet. It was the most luxurious piston airliner of its era — and one of the most mechanically punishing. Four Pratt & Whitney R-4360 Wasp Major engines, each with 28 cylinders, meant 224 spark plugs and 224 valves had to work correctly every single departure. The R-4360 was the largest radial engine Pratt & Whitney ever mass-produced, and keeping four of them running on long overwater routes pushed crews and maintenance teams to the limit. This video covers the full story — the double-bubble fuselage, the engineering behind the "corncob" engine, the propeller failures that triggered fleet-wide airworthiness directives, the cockpit-design trap that caught one crew off guard, and the night a Pan Am captain held a crippled Stratocruiser over the Pacific until dawn. This is what it cost to fly the most ambitious piston airliner ever built.