The U.S. military's Boeing E-4B Nightwatch — better known as the "Doomsday Plane" — made a rare and eye-catching landing at Los Angeles International Airport this week, triggering a wave of online speculation and concern amid heightened global tensions, the Los Angeles Times reported. 

Aviation watchers spotted the massive aircraft Thursday as it approached LAX, marking what appears to be the first time the highly specialized plane has landed at the busy commercial airport.

The U.S. Air Force describes the E-4B as a "highly survivable command, control and communications center," designed to operate in the most extreme national emergencies.

The E-4B serves as the National Airborne Operations Center, capable of functioning as a command post in the sky for the president, the war secretary, and the Joint Chiefs of Staff if ground-based command centers are destroyed or disabled.

Its sudden appearance in Southern California sparked alarm on social media, with some users openly questioning whether a major conflict was coming.

"WAR IMMINENT?" one defense-oriented user posted on X.

In reality, the flight had a far more routine explanation. The aircraft was transporting War Secretary Pete Hegseth to Southern California as part of his monthlong "Arsenal of Freedom" tour, which highlights U.S. defense manufacturing and industrial capacity.

Hegseth spoke Thursday at Rocket Lab, a Long Beach-based aerospace manufacturer, during the second stop of the tour, according to the War Department.

The E-4B is a heavily modified Boeing 747 designed to withstand electromagnetic pulses from nuclear detonations and operate during the most catastrophic scenarios. The Air Force maintains at least one E-4B on continuous alert.

In a national emergency, the aircraft lets senior leaders direct U.S. forces, execute emergency war orders, and coordinate with civil authorities.

It can remain airborne for days with midair refueling and carries a crew of up to 112 people, including military officers, communications specialists, and security personnel. Inside are briefing rooms, secure communications hubs, and workspaces designed for crisis leadership.

The Air Force operates a fleet of four E-4Bs, primarily based at Offutt Air Force Base in Nebraska.

While the Air Force plans to eventually replace the aging fleet under the Survivable Airborne Operations Center program, the Nightwatch remains a central pillar of U.S. nuclear deterrence and emergency preparedness.