Patrol Squadron 51 (VP-51)
Bombing Squadron 101 (VB-101)
Patrol Bombing Squadron 101 (VPB-101)
United States Navy (USN)

Background
Patrol Squadron 51 (VP-51) was established in the United States Navy (USN) from VP-54 and VP-12 at NAS Miramar.

Wartime History
Assigned twelve PB4Y-1 Liberator (USN version of the B-24D Liberator) that retained their U.S. Army pain scheme but were assigned squadron numbers 51-P-? with the last digit was 1 to 12 for the first dozen plane numbers). Flying to the combat zone, VP-51 departed Barber's Point Airfield on Oahu then ferried their bombers across the Pacific to the South Pacific (SoPAC).

On February 1, 1943 redesignated Bombing Squadron 101 (VB-101).

On February 13, 1943 nine PB4Y-1 Liberators from took off from Henderson Field on Guadalcanal on a bombing mission against Japanese shipping in the Buin-Shortland area. This was the squadron's first combat mission in the South Pacific (SoPAC).

On February 14, 1943 nine PB4Y-1 Liberators each armed with a single 1,000 pound bomb took off from Henderson Field on Guadalcanal on a mission to bomb shipping in the Buin-Shortland area. The bombers were escorted by ten P-38 Lightnings from the 347th Fighter Group, 339th Fighter Squadron plus twelve F4U Corsairs from VMF-124 took off from Fighter 2 (Kukum). Around 11:45am the PB4Y-1 Liberators released their bombs over shipping off southern Bougainville. They claim "several direct hits were made on an AK which was seen to blow up. There was also a near miss on a DD." In fact, their bombs result in two near misses that bracket Kisaragi Maru. Also, two near misses bracket Hitachi Maru causing hull damage and killing four, the damaged vessel was beached near Lamuai on southern Bougainville. After the bomb run, the Japanese fighters pressed their attacks against the bombers and fighters. Lost is PB4Y-1 Liberator 31950 pilot Lt. Jay D. Bacon, Jr. (MIA), PB4Y-1 Liberator 31970 pilot Lt. Stuart T. Cooper (MIA).

On March 5, 1943 nine PB4Y-1 Liberators took off from Henderson Field on Guadalcanal on a mission to bomb Japanese shipping off southern Bougainville. Over the target, no Japanese ships were observed but several searchlights were observed from Buin to Kahili area and and light anti-aircraft fire. Lost returning is PB4Y-1 Liberator 31948 pilot Lt. Frank M. Fisler (MIA).

On July 17, 1943 at 1:28am six PB4Y-1s (three from VB-101 and three from VB-102) took off from Carney Field on Guadalcanal on a night mission for a predawn bombing mission against Kahili Airfield (Buin) on southern Bougainville. Inbound, one aborts. After bombing, the VB-102 bombers are intercepted a J1N1 Irving night fighter. Lost is PB4Y-1 Liberator 31952 pilot Lt(jg) John B. Haskett (MIA) temporarily assigned to VB-102.

On October 1, 1944 redesigned Patrol Bombing Squadron 101 (VPB-101).

On October 23, 1944 lost is PB4Y-1 32277 pilot Lt. Harold H. Lewis Jr. (MIA) on a patrol mission over "sector one" possibly intercepted by enemy fighters.

Lineage
During June 1941 designated Patrol Squadron 51 (VP-51).
On February 1, 1943 redesignated VB-101 (other sources state March 1, 1943).
On October 1, 1944 redesignated Patrol Bombing Squadron 101 (VPB-101).

Aircraft
During early 1943, operated the PB4Y-1 Liberator from Guadalcanal. The first fourteen bombers were assigned squadron number 51-P-? (last digit 1-14 for the complement of twelve bombers plus two replacement aircraft).

References
Other sources state VP-51 was redesignated VP-101 on March 1, 1943 incorrectly.
Thanks to Jim Sawruk for additional information