Early PB4Y-2 BuNo. 59374
Distinguishing Features of the PB4Y-2 Privateer
The PB4Y-2 Privateer, the US Navy’s final and most advanced version of the B-24 Liberator, possessed several distinguishing features that set it apart from earlier models. These features were largely focused on enhancing its capabilities for long-range maritime patrols, improving stability, and increasing defensive firepower. Here are the key distinguishing features:
Single Vertical Tail: Unlike the twin-tail configuration of the B-24 and the PB4Y-1, the PB4Y-2 featured a single, large vertical tail. This change was implemented to improve the aircraft’s stability, particularly during low-altitude operations. The single tail provided more stable flight characteristics, reducing yaw (side-to-side movement) and making the aircraft easier to control.
Lengthened Forward Fuselage: The PB4Y-2 had a 7-foot (2.13-meter) extension added to the forward fuselage. This modification served multiple purposes:
- Accommodate a Flight Engineer’s Station: The extension allowed for a dedicated flight engineer’s station, reflecting the increased complexity of the aircraft’s systems.
- House Advanced Electronics: The lengthened fuselage provided space for additional radio, navigation, radar, and radar countermeasures (RCM) equipment.
- Improve Visibility: The extended nose also improved visibility for the bombardier during low-level attacks.
Upgraded Engines: The PB4Y-2 was powered by four Pratt & Whitney R-1830-94 Twin Wasp engines, which were lighter and more powerful than the R-1830-65 engines used in the PB4Y-1. These engines, however, were not equipped with turbo-superchargers. This was a deliberate design choice, as the PB4Y-2 was primarily intended for low- to medium-altitude patrols, where turbo-superchargers were less crucial. The removal of turbo-superchargers also resulted in weight savings, further enhancing the aircraft’s performance at lower altitudes.
Increased Armament: The PB4Y-2 boasted a formidable defensive armament, exceeding that of any other US Navy patrol aircraft during World War II. It featured five powered turrets, each armed with twin .50-caliber Browning M2 machine guns:
- Nose Turret: Typically an ERCO 250SH-2/3 or Emerson 250CE-1.
- Dorsal Turrets: Two Martin 250CE upper deck turrets.
- Waist Turrets: Two ERCO 250TH-1 teardrop-shaped blister turrets.
- Tail Turret: A Consolidated 250CH or MPC 250CH-6.
This heavy armament, combined with the aircraft’s stability and endurance, made the PB4Y-2 a potent weapon against enemy ships and aircraft, allowing it to operate effectively in contested airspace.
Redesigned Nacelles: The engine nacelles on the PB4Y-2 were redesigned, with oil cooler scoops located above and below the nacelle, rather than on the sides as in the B-24. This alteration was likely made to accommodate the different engine type and improve airflow.
These distinguishing features transformed the PB4Y-2 into a dedicated and capable maritime patrol aircraft, significantly improving upon the earlier PB4Y-1 and ensuring its effectiveness in the Pacific Theater during the latter stages of World War II and beyond. The PB4Y-2 continued to serve in various roles after the war, highlighting its versatility and enduring design.