Two U.S. Navy aircraft carriers joined up with a Japanese helicopter-destroyer for an exercise in the Philippine Sea over the weekend, a gathering meant to show the two allies’ ability to quickly mass forces during crises.

The meeting of some of world’s largest warships involved the Carl Vinson and Japan-based Ronald Reagan, joined by the Japan Maritime Self-Defense Force helicopter-destroyer JS Hyuga. The drill, dubbed a Multi-Large Deck Event in naval lingo, took place in the Philippine Sea between Nov. 4 and Nov. 8.

It marked the second occasion over the span of a few days that a pair of US Navy aircraft carriers conducted exercises with each other. The Gerald R. Ford and Dwight D. Eisenhower staged a joint training the Eastern Mediterranean Sea the previous week.

This week’s event was also the second such meetup to be held in the Indo-Pacific this year, as the carriers Ronald Reagan and Nimitz were joined by Japan’s JS Izumo for a similar occasion in June.

Defense News was part of a small group of international media flown to the ships at a location roughly 500 miles (800 km) east of the Philippines’ main island of Luzon.

U.S. Navy Capt. Matthew Thomas, commander of the Carl Vinson, said the participating ships and aircraft undertook a variety of training missions, including air defense drills, sea surveillance, defensive air counter tactics and coordinated maneuvers.

Rear Adm. Carlos Sardiello, commander of the U.S. Navy’s Strike Group One, told reporters aboard the Ronald Reagan that the drill was meant as a “demonstration on how we can rapidly move to a point of crisis and interoperate and cooperate.”

The Carl Vinson had left its homeport of San Diego on Oct. 12, according to video footage captured by a publicly accessible webcam. Navy Times had previously reported that the sea service declined to disclose when the ship left port.

Improving the interoperability between the US Navy and Japanese forces was also a key objective of the exercise, according to the commander of the Ronald Reagan, Capt. Daryle Cardone. “Having been here last year and this year we see each and every time that we interoperate with our partners that the exercises increase in complexity and depth,” he said.

The Navy used a Bell-Boeing CMV-22B Osprey tiltrotor plane and a Northrop-Grumman C-2A Greyhound turboprop transport aircraft to ferry reporters from Kadena Airbase in Okinawa to the carrier and back, respectively, a practice the service calls Carrier Onboard Delivery, or COD.

Officials are in the process of phasing out the Northrop planes for such COD journeys, with the newer Ospreys taking over the missions.