The B-26 began to equip the 22nd Bombardment Group at Langley Field, Virginia, in February 1941, replacing the Douglas B-18 Bolo, with a further two groups, the 38th and 28th, beginning to equip with the B-26 by December 1941.
Immediately following the Japanese Attack on Pearl Harbor, the 22nd BG was deployed to the South West Pacific, first by ship to Hawaii, then its air echelon flew the planes to Australia.
The 22nd BG flew its first combat mission, an attack on Rabaul which required an intermediate stop at Port Moresby, New Guinea, on 5 April 1942.

A second group, the 38th, began receiving B-26s in November 1941 and began transitioning into them at Patterson Field, Ohio.
There, the 38th continued the testing of the B-26, including its range and fuel efficiency.
Immediately after the entry of the United States into World War II, plans were tentatively developed to send the 38th BG to the South West Pacific and to equip it with B-26Bs fitted with more auxiliary fuel tanks and provisions for carrying aerial torpedoes.
Three 38th BG B-26Bs were detached to Midway Island in the buildup to the Battle of Midway, and two of them, along with two B-26s detached from the 22nd BG, carried out torpedo attacks against the Japanese Fleet on 4 June 1942.
Two were shot down and the other two were so badly damaged that they were written off after the mission.
Their torpedoes failed to hit any Japanese ships, although they did shoot down one Mitsubishi A6M Zero fighter and killed two seamen aboard the aircraft carrier Akagi with machine-gun fire.
Notably, one of them, Susie Q, after dropping its single torpedo and searching for a safer escape route, flew directly down the length of the Akagi while being fired upon by fighters and anti-aircraft fire, which had to hold their fire to avoid hitting their own flagship.
Another, after being seriously damaged by anti-aircraft fire, didn’t pull out of its run, and instead headed directly for Akagi's bridge.
The aircraft, either attempting a suicide ramming, or out of control due to battle damage or a wounded or killed pilot, narrowly missed crashing into the carrier's bridge, before it cartwheeled into the sea.

From approximately June 1942, B-26 squadrons of the 38th BG were based in New Caledonia and Fiji.
From New Caledonia, missions were flown against Japanese bases in the Solomon Islands.
On one occasion, a B-26 was credited with shooting down a Kawanishi H6K flying boat.
In 1943, it was decided that the B-26 would be phased out of operations in the South West Pacific Theater in favor of the North American B-25 Mitchell.
Nevertheless, the 19th Bombardment Squadron of the 22nd BG continued to fly missions in the B-26.
The B-26 flew its last combat mission in the theater on 9 January 1944.

Two more squadrons of torpedo armed B-26s equipped the 28th Composite Group and were used for anti-shipping operations in the Aleutian Islands Campaign, but there are no records of any successful torpedo attack by a USAAF B-26.

Comedian George Gobel famously joked about being an instructor for this aircraft at Frederick Army Airfield (now Frederick Regional Airport) during the Pacific battles, boasting that "not one Japanese aircraft got past Tulsa".
The B-26 began to equip the 22nd Bombardment Group at Langley Field, Virginia, in February 1941, replacing the Douglas B-18 Bolo, with a further two groups, the 38th and 28th, beginning to equip with the B-26 by December 1941. Immediately following the Japanese Attack on Pearl Harbor, the 22nd BG was deployed to the South West Pacific, first by ship to Hawaii, then its air echelon flew the planes to Australia. The 22nd BG flew its first combat mission, an attack on Rabaul which required an intermediate stop at Port Moresby, New Guinea, on 5 April 1942.
A second group, the 38th, began receiving B-26s in November 1941 and began transitioning into them at Patterson Field, Ohio. There, the 38th continued the testing of the B-26, including its range and fuel efficiency. Immediately after the entry of the United States into World War II, plans were tentatively developed to send the 38th BG to the South West Pacific and to equip it with B-26Bs fitted with more auxiliary fuel tanks and provisions for carrying aerial torpedoes. Three 38th BG B-26Bs were detached to Midway Island in the buildup to the Battle of Midway, and two of them, along with two B-26s detached from the 22nd BG, carried out torpedo attacks against the Japanese Fleet on 4 June 1942. Two were shot down and the other two were so badly damaged that they were written off after the mission. Their torpedoes failed to hit any Japanese ships, although they did shoot down one Mitsubishi A6M Zero fighter and killed two seamen aboard the aircraft carrier Akagi with machine-gun fire. Notably, one of them, Susie Q, after dropping its single torpedo and searching for a safer escape route, flew directly down the length of the Akagi while being fired upon by fighters and anti-aircraft fire, which had to hold their fire to avoid hitting their own flagship. Another, after being seriously damaged by anti-aircraft fire, didn’t pull out of its run, and instead headed directly for Akagi's bridge. The aircraft, either attempting a suicide ramming, or out of control due to battle damage or a wounded or killed pilot, narrowly missed crashing into the carrier's bridge, before it cartwheeled into the sea.
From approximately June 1942, B-26 squadrons of the 38th BG were based in New Caledonia and Fiji. From New Caledonia, missions were flown against Japanese bases in the Solomon Islands. On one occasion, a B-26 was credited with shooting down a Kawanishi H6K flying boat. In 1943, it was decided that the B-26 would be phased out of operations in the South West Pacific Theater in favor of the North American B-25 Mitchell. Nevertheless, the 19th Bombardment Squadron of the 22nd BG continued to fly missions in the B-26. The B-26 flew its last combat mission in the theater on 9 January 1944.
Two more squadrons of torpedo armed B-26s equipped the 28th Composite Group and were used for anti-shipping operations in the Aleutian Islands Campaign, but there are no records of any successful torpedo attack by a USAAF B-26.
Comedian George Gobel famously joked about being an instructor for this aircraft at Frederick Army Airfield (now Frederick Regional Airport) during the Pacific battles, boasting that "not one Japanese aircraft got past Tulsa".
Martin B-26 Marauder