29 May 1943 – attacked submarine pens and locks at Saint-Nazaire. Smaller strikes were made at Rennes naval depot and U-boat yards at La Pallice. In the attack, seven YB-40s were dispatched to Saint-Nazaire; they were unable to keep up with B-17s on their return from the target and modification of the waist and tail gun feeds and ammunition supplies was found to be needed. The YB-40s were sent to Technical Service Command at the Abbots Ripton 2nd Strategic Air Depot for modifications.
15 June 1943 – four YB-40s were dispatched from Alconbury in a raid on Le Mans after completion of additional modifications.
22 June 1943 – attack on the I.G. Farben Industrie Chemische Werke synthetic rubber plant at Hüls. The plant, representing a large percentage of the Germany’s synthetic rubber producing capacity, was severely damaged. In the raid, 11 YB-40s were dispatched; aircraft 42-5735 was lost, being first damaged by flak and later shot down by Uffz. Bernhard Kunze in a Focke-Wulf Fw 190A-2 of JG 1 over Pont, Germany. The 10 crew members survived and were taken prisoner.
25 June 1943 – attack on Blohm & Voss sub shops at Oldenburg. This was the secondary target, as the primary at Hamburg was obscured by clouds. In this raid, seven YB-40s were dispatched, of which two aborted. Two German aircraft were claimed as destroyed.
26 June 1943 – scheduled but aborted participation in attack on the Luftwaffe air depot at Villacoublay, France (primary target) and also the Luftwaffe airfield at Poissy, France. The five YB-40s assigned to the attack were unable to form up with the bombing squadron, and returned to base.
28 June 1943 – attack on the U-boat pens at Saint-Nazaire. In the raid, the only serviceable lock entrance to the pens was destroyed. In this attack, six YB-40s were dispatched, and one German aircraft was claimed as destroyed.
29 June 1943 – scheduled participation in attack on the Luftwaffe air depot at Villacoublay, but aircraft returned to Alconbury due to clouds obscuring the target. In the raid, two YB-40s dispatched, one aborted.
4 July 1943 – attacks on aircraft factories at Nantes and Le Mans, France. In these raids, two YB-40s were dispatched to Nantes and one to Le Mans.
10 July 1943 – attack on Caen/Carpiquet airfield. In this raid, five YB-40s were dispatched.
14 July 1943 – attacked Luftwaffe air depot at Villacoublay. In this raid, five YB-40s were dispatched.
17 July 1943 – YB-40s recalled from a raid on Hannover due to bad weather. In this raid, two YB-40s were dispatched.
24 July 1943 – YB-40s recalled from an attack on Bergen, Norway due to cloud cover. In this raid, one YB-40 was dispatched.
28 July 1943 – attack on the Fieseler aircraft factory at Kassel. In this raid, two YB-40s were dispatched.
29 July 1943 – attack on U-boat yards at Kiel. In this raid, two YB-40s were dispatched.
Altogether of the 59 aircraft dispatched, 48 sorties were credited. Five German fighter kills and two probables were claimed, and one YB-40 was lost, shot down on 22 June mission to Hüls, Germany. Tactics were revised on the final five missions by placing a pair of YB-40s in the lead element of the strike to protect the mission commander.
Serials from Freeman:
41-24341 XB-40 prototype
42-5733 Peoria Prowler
42-5734 Seymore Angel, later renamed Red Balloon, Old Ironsides