The takeoff speed of a Boeing 777, specifically the popular 777-300ER, is not a single fixed number; it depends heavily on the aircraft's weight, the outside air temperature, and the runway length. Generally, the rotation speed (Vr)—the point where the pilot pulls back on the stick to lift the nose—falls between 150 and 180 knots (roughly 172 to 207 mph or 277 to 333 km/h). A fully loaded 777 carrying maximum fuel and passengers for a long-haul flight like London to Singapore will require a much higher speed to generate enough lift compared to a shorter ferry flight. Environmental factors also play a role: on a hot day in a high-altitude city like Denver, the air is less dense, requiring a higher ground speed to achieve the necessary lift. In 2026, advanced flight management computers calculate these "V-speeds" (V1, Vr, V2) precisely for every departure to ensure the aircraft can safely clear obstacles even if an engine fails at the most critical moment of takeoff.