Sikorsky PBS / S-44 Excalibur
In 1935, the US Navy initiated development of a new patrol bomber larger than the PBY Catalina that would have increased performance and weapon load capability. Consolidated and Sikorsky submitted proposals, and each received order for two prototypes as the XPB2Y-1 and XPBS-1. Both the prototypes first flew in 1937 but the Navy did not have funds at that time to procure the aircraft. Sikorsky sold the XPBS-1 to civilian customers, and Consolidated had to wait 15 months before order of the improved PB2Y-2 was placed.
The XPBS-1, a large four-engined monoplane flying boat built by Sikorsky Aircraft, made its first flight on 09 September 1937. This aircraft (BuNo. 9995), constructed as a long-range patrol plane, was later used as a transport. Only one prototype was made for competing for the contract eventually given to Consolidated Aircraft for the PB2Y series of Coronado boats. Although never ordered into production, the NACA evaluated the craft in 1938. Many aircraft were flown at Langley to give an appraisal from the highly experiences staff. These appraisals often meant that the aircraft was with the NACA only briefly.
In 1939 XPBS-1 was temporarily assigned to Patrol Wing Five; to be transferred later to Patwing Two and then it was was assigned to the Navy transport unit VR-2 of the Air Transport Service. The XPBS-1 was employed by the Navy in a transport role in 1940-42. On 17 December 1941, President Franklin D. Roosevelt ordered Chester William Nimitz to duty as Commander in Chief, Pacific Fleet (CinCPac) with the rank of admiral, effective 31 December 1941. Nimitz directed the Pacific Fleet in the critical spring of 1942 that culminated in the victories at Coral Sea (7-8 May) and Midway (4-6 June). Nimitz nearly perished less than a month after Midway when the Sikorsky XPBS-1 (BuNo 9995) carrying the admiral hit a submerged log when landing at Naval Air Station, Alameda, CA, on 30 June 1942. The impact threw the men around inside the big flying boat like dice in a box, inflicting injuries on all on board, and they soon began struggling to escape as the aircraft filled with water. Nimitz, who suffered scratches and abrasions in the mishap, immediately showed concern for those who had been hurt in the crash (one of the flight crew, Lieutenant Thomas M. Roscoe, died in the mishap) and remained topside on the wreckage to direct rescue operations, refusing to move until searchers finished their grim task of investigating the wrecked flying boat for survivors.
The S-44, the world's longest range commercial aircraft, evolved from the Sikorsky XPBS-1 experimental patrol bomber to become perhaps the most successful commercial flying boat. It was the only aircraft to have flown commercial scheduled service nonstop across the north and south Atlantic.
Accommodating 40 passengers over short ranges or 16 with sleeping bunks, it was developed for American Export Airlines for use on its trans-atlantic service. For its planned Europe-Service, the American Export Airlines (AEA) ordered three Vought-Sikorsky VS-44 Excalibur flying boats. In February 1942, AEA obtained transport rights for the New York - Foynes distance which was opened on 22 June 1942. The Naval Air Transport Service carried its transatlantic flights out as well. The last S-44 was built in 1942.
Excambian ended up in Catalina Island (CA) service 1957, then as Antilles Air Boats, retired in 1969 and was donated to the Naval Air Museum at Pensacola FL, finally to New England Air Museum (CT) after rebuild by Sikorsky volunteers.
The S-44 was the last fixed-wing aircraft built by Sikorsky. Sikorsky's flying boats made little money, and in 1938, United Aircraft directed Sikorsky to stop building them and gave him $250,000 for helicopter development. He would go on to make his most important contributions in the area of helicopter design.
PBS (Model S-44) 1937 = ChwMFb;
four 1200hp P&W Wasps.
Essentially USN version of S-36;
ceiling: 20,800'; ff:
Length: 76' 3" 23.2 m
Height: 26' 11" 8.2 m
Wingspan: 124' 0" 37.7 m
Gross Weight: 47,455 lb 21,521 kg
Propulsion No. of Engines: 4
Powerplant: Pratt & Whitney XR-1830-68
Horsepower (each): 900
Performance Max Speed: 214 mph 344 km/h 185 kt
Ceiling: 21,200 ft 6,461 m
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