Shillelagh, Dakota Territory Air Museum’s P-51B: Winter 2025

Fixtures were created or assembled, and spars and ribs were fabricated or restored, and then painted. Now is the time to bring them all together and assemble Shillelagh’s wings.  The wings are taking shape!

 The period between April and August 1944 encompasses the lead-up to the D-Day invasion, the invasion itself, and its immediate aftermath. During those five months, David O’Hara’s third P-51B (42-106602) Shillelagh, flew 95 missions over enemy territory.

Before the Normandy invasion, Allied strategists agreed that air superiority was essential to its success. Without it, the invasion force could be decimated before gaining a foothold on the French beaches.

Achieving the necessary air superiority over the Luftwaffe required crippling Germany’s aircraft and oil industries. Before 1944, the Eighth Air Force had conducted raids to destroy the German aircraft industry but had suffered unsustainable losses to their bomber fleet. The pre-war doctrine that the bombers could protect themselves without fighter escort proved disastrously false. The Schweinfurt-Regensburg raids of 1943 were examples of these losses.  In fact, the second Schweinfurt raid on October 14, 1943, became known as “Black Thursday” because of the high losses of B-17s and their crews.

“By the time the Americans returned home, they had lost 60 B-17s, another 17 were no longer airworthy, and an additional 121 received minor damage. That was only the material loss. The number of aircrew killed, wounded, or missing in action was more than 600, totaling almost 20 percent of the men sortied. These grim numbers were double what 8th Air Force planners consider an acceptable loss rate.”¹

After the Black Thursday catastrophe, long-range penetration raids into Germany were suspended until a means was found to mitigate losses.

Clearly, a long-range escort fighter was necessary to achieve the air superiority prerequisite to the invasion of Europe. 

Fortunately, in November of 1943, the North American P-51B arrived in the European Theatre. This latest version of the Mustang had both greatly increased range and much better high-altitude performance. These improvements were possible because the earlier Allison engine with a single-stage supercharger had been replaced with the two-stage, two-speed supercharged Packard (Rolls Royce) V-1650-3. The Packard “Merlin” was rated at about 490 more horsepower than the Allison at 25,000 feet. As importantly, the range was increased from the 750 miles and  1,375 with drop tanks) in the P-51A, to 1,180 miles (1,900 with drop tanks) in the new P-51B.

The Allison-powered Mustangs were great fighters in the role for which they were originally designed, low to medium-altitude operations, and the British continued using them in that role through the end of the war in Europe. 

However, the Merlin-engined P-51B offered new capabilities, and the range and high altitude performance needed to escort the B-17s and B-24s all the way to targets deep in Germany at the 25-30,000 ft. altitudes the bombers flew in combat.

The first P-51Bs to reach England were assigned to the 354th Fighter Group under the 9th Air Force. The 9th’s primary mission in Europe was tactical support for ground troops.  However, when General H.H. “Hap” Arnold learned of the capabilities of the new long-range Mustangs, he decided that the new P-51B could be the answer to the 8th Air Force bombers’ urgent need for a long-range escort.²  Based on this capability, Arnold operationally loaned the 354th Fighter Group to the Eighth Air Force to fly long-range escort missions. Shillelagh’s group, the 354th, became known as the Pioneer Mustang Group.

¹ Dr John M Curatola LtCol USMC (Ret), “Black Thursday” October 14, 1943: The Second Schweinfurt Bombing Raid,National WWII Museum, https://www.nationalww2museum.org/war/articles/black-thursday-october-14-1943-second-schweinfurt-bombing-raid

² Richard H. Kohn and Joseph P Harahan, USAF Warrior Studies, Condensed Analysis of the Ninth Air Force in the European Theater of Operations, New Imprint, Office of Air Force History, United States Air Force, Washington D.C., 1984, page 16

Shillelagh wasn’t one of the first P-51Bs assigned to the 354th Fighter Group. It was David O’Hara’s third P-51B, which arrived in England in early April of 1944. Shillelagh (42-106602) flew its first combat mission on 15 April 1944.

The 354th Fighter Group was comprised of 3 squadrons, the 353rd, 355th, and 356th. 

David O’Hara’s Shillelagh and Ken Dahlberg were assigned to the 353rd FS. By late May of 1944, the 354th was flying fewer escorts and more tactical missions in preparation for the invasion of “fortress Europe”. 

There are statistics and historical reports that show that the P-51B changed the loss rate on long-range bombing missions significantly, but an experience at Oshkosh AirVenture in 2018 best illustrated the significance of the P-51B.

A woman wheeled an elderly man in a wheelchair up to P-51C Lope’s Hope 3rd and introduced herself as Cynthia Blisard, and her father as WWII veteran Harry Theobold. Harry had come to Oshkosh specifically to see B-17s, B-24s, and P-51s. While he didn’t see a B-24, he was more than happy with the Mustang turnout. The bombers were important to Harry because he was a tail gunner, with 15 missions in B-24s, and 19 missions in B-17s. When I asked him about his interest in the Mustang he replied “Once the Mustangs arrived and could escort us all the way to the target, we didn’t see German fighters anymore. Those P-51 pilots saved my life.”