The U.S. is now testing the next generation of its so-called “doomsday plane.” On August 7, Sierra Nevada Corporation completed the inaugural flight of the new E-4C Survivable Airborne Operations Center, marking the start of flight and ground tests that could stretch into 2026, as reported by FlightGlobal.
This new aircraft, based on the updated Boeing 747-8I platform, is being built to replace the nearly 50-year-old E-4B Nightwatch jets. Once in service, the E-4C will act as a flying war room, designed to keep top U.S. leadership connected and in command even if ground-based control centers are destroyed.
So what makes the E-4C so capable? First, it’s hardened to withstand electromagnetic pulses and other electronic threats – critical in a nuclear or cyber conflict. It will also feature modern open-architecture systems that are easier to upgrade over time, along with advanced secure communications and satellite links. The new model will be refuelable mid-air, allowing it to stay airborne far longer than its predecessor. Ground and flight testing at facilities in Ohio and Kansas will validate all of this before the full set of modifications begins.
Sierra Nevada is turning five Boeing 747-8I passenger jets – sourced from Korean Air – into these flying command centers and has already built up the necessary hangars and infrastructure at its Dayton, Ohio hub.
The current E-4Bs still carry out critical roles – transporting top defense officials, coordinating communications, and staying ready as airborne backups—but the new E-4C is expected to elevate all that with updated technology, better resilience, and more flexibility.
The full fleet is expected to be delivered by around 2036, ensuring that even in the most chaotic scenarios, the U.S. government can stay connected, responsive, and in control.
