World · East Asia & Pacific · 2 hrs ago
US Nuclear-Detection Plane Flies Over Sea of Japan
A US WC-135R nuclear-detection plane flew over the Sea of Japan on October 20, after taking off from Kadena Air Base in Okinawa and later returning there.
It spent several hours over the sea, and its flight lasted more than 10 hours.
The plane can collect radioactive particles from the air to help detect a nuclear test and identify whether it used uranium or plutonium.
Its publicly reported appearance near the Korean peninsula was the first since 2023–24, when concern about a possible North Korean nuclear test was high.
North Korea has recently defended its nuclear weapons programme while criticizing joint military exercises involving South Korea, the United States and Japan.
The flight may have been a check of readiness for a possible nuclear test, but that explanation is an assessment, not a confirmed mission; no further action was specified.
A US WC-135R nuclear-detection aircraft flew over the Sea of Japan on October 20 and remained there for several hours.
The plane took off from Kadena Air Base in Okinawa, flew via the East China Sea, and returned to Kadena after a flight of more than 10 hours.
The aircraft can collect and analyze radioactive materials in the air, including particles that could indicate a nuclear test.
The flight came amid renewed North Korean claims defending its nuclear weapons program, and observers said it may have tested readiness for a possible nuclear-related activity.
A South Korean military official said the flight could also warn North Korea that its nuclear activities are being monitored.
- Who
- A US Air Force WC-135R nuclear-detection aircraft.
- What
- It flew over the Sea of Japan for several hours before returning to Kadena Air Base.
- When
- October 20. The report was published on October 21, 2026.
- Where
- Over the Sea of Japan, after taking off from Kadena Air Base in Okinawa and flying via the East China Sea.
- Why
- Observers said it may have been checking readiness to collect nuclear material amid concern about possible North Korean nuclear activity. The purpose was not confirmed.
This story does not have two clearly opposing sides.
A WC-135R took off from Kadena Air Base, flew via the East China Sea to the Sea of Japan, and stayed there for several hours.
The aircraft returned to Kadena after a flight of more than 10 hours.
Donga Ilbo published its report on the flight.
- Aircraft
- WC-135R
- Departure and return base
- Kadena Air Base, Okinawa
- Flight duration
- More than 10 hours
- Sea area
- Sea of Japan
- Fleet size
- The US Air Force has three WC-135R aircraft.
1 source
What people are saying
North Korea should know that we are watching all nuclear-related activities, so this can also be seen as a warning not to cross the red line.