The "Seoul Patrol"

(Source- Channel A News Top Ten, 4.1) Title: Surveillance of North Korea, US special reconnaissance aircraft arrive. Left to Right, Rivet Joint, Cobra Ball, and Combat Sent.


(Source- Shin In Kyun, Defense Daily, 5.30) Rivet Joint communications and signals intelligence collection strategic reconnaissance aircraft dispatched from Offut AFB where it is attached to 55th Air Force Group, forward deployed to Okinawa, Japan, Kadena AFB.

Aircraft Spots put up a comment on March 20, 2019 advising followers:

RC135s, U2s, P8s, EP3s, and E3s are up over South Korea every day and they're not a sign of anything about to happen with North Korea.

Start worrying when you see an RC-135S Cobra Ball in the region or B-52s flying to the Korean Peninsula, which you'll find here first!

https://twitter.com/aircraftspots?lang=en

On March 29 (Z time) , Cobra Ball, arrived at Kadena AFB, Okinawa, Japan. So Shin In Kyun's Daily Defense program reported Aircraft Spots information, and Channel A News picked it up on their Top Ten program in South Korea. Since that time, Aircraft Spots has reported on what I've labelled the Seoul Patrol, on April 8, 15 (RC-135S East China Sea), 17, 18, 21, 28, continuing to May 7, 8, 12, 13, 14, 15, 16, 24 (EP-3), 26 (EP-3) and 29th. Picking up on Aircraft Spots' comment Shin reported in his April 1 podcast on this subject matter that the arrival of Cobra Ball in Okinawa from Diego Garcia March 29 was an indication that ballistic missile launches from North Korea were imminent. Cobra Ball had been operating in the Indian Ocean region to observe India's anti-satellite missile launch on March 27. So the Aircraft Spots analysis apparently proved out as the anticipated ballistic missile launches occurred on May 4, and May 9 as described in previous reports here. (See US-DPRK: Mine's Bigger Than Yours, May 10.) Shin contends in his latest podcast, May 30, on this subject matter that the combined presence on May 29, of Rivet Joint and Combat Sent, in the region give the US national command authority and theater commanders unrivaled capability to react to any further ballistic missile launches, analyse them, and report intelligence assessments in a timely manner. Naturally, Shin anticipates further provocations in the form of North Korean ballistic missile test launches, perhaps of a longer range than the launches last month. Aircraft spots reports today suggests that Cobra Ball is still in the region.