Submarine Hunters: Tracker and Viking

Although aircraft have been involved in anti-submarine warfare (ASW) since the First World War, it was not until the 1950s that a purpose-built ASW aircraft, equipped with detection systems and weapons, first entered service. Let us look at the history of two of the most significant submarine hunters.

Grumman Tracker

The 1950s were eventful years in terms of the development of ASW aircraft. Grumman Guardians entered service with the U.S. Navy (USN) in 1950, introducing a new concept in combating submarines. Guardians operated in pairs, consisting of ‘hunters’ and ‘killers.’ The ‘hunters’ carried detection equipment and were tasked with locating submarines, whilst ‘killers’ were armed and responsible for destroying the vessels. The USN was not satisfied with the concept and announced the requirement for a single airframe, carrier-based, twin-engined aircraft, capable of filling the ‘hunter’ and ‘killer’ roles simultaneously. Grumman responded with the XS2F-1, which first flew in 1952. With the Korean War as a backdrop, the USN placed an order for two prototypes and fifteen production aircraft at the same time. Initially, the production version was designated S2-F, which earned it the affectionate nickname ‘Stoof.’ Officially, it was called the Tracker. The small airframe was powered by two Wright Cyclone radial engines and had a range of more than 2 000 km. It had six underwing hardpoints and a weapons bay, which could carry bombs, rockets, torpedoes, mines and depth charges. Another advantage was the ability to deliver nuclear depth bombs. Unlike its ASW predecessors, the Tracker was generously equipped with detection equipment, which included sonobuoy ejector tubes, a 70-million-candlepower searchlight, a search radar in a retractable radome, a Magnetic Anomaly Detector (MAD) boom, Signal-Underwater-Sound (SUS) devices and an electronics countermeasures’ (ECM) antenna. Designed with carrier operations in mind, the Tracker was equipped with folding wings and an arrestor hook, whilst a large rudder enabled the aircraft to fly on one engine. The crew consisted of a pilot, co-pilot and two systems officers. The successful TF-1 Trader onboard delivery aircraft and WF-1 Tracer airborne early warning aircraft were based on the Tracker design. Trackers saw service with many countries all over the world and were continuously being upgraded. Many Trackers, such as those used by Argentina and Taiwan, were later converted to Turbo Trackers, powered by turboprop engines. As Trackers were being replaced by more modern military aircraft, they increasingly saw service with civilian operators as fire bombers, and were known as Firecats and Turbo Firecats.

Lockheed Viking

Advances in Soviet submarine technology during the 1960s made the Tracker seem more and more obsolescent. As a result, the USN realised the need for a more capable ASW aircraft. This time, Grumman was beaten by Lockheed in producing the contract-winning design. Lockheed’s aircraft, ultimately designated the S-3A Viking, first flew in 1972 and entered service five years later. Although it was purpose-built as an ASW aircraft, the Viking proved to be so versatile, that it would later become known as the ‘Swiss Army Knife’ of naval aviation. According to the Lockheed website, it was designed to conduct ‘surface and undersea warfare, mine warfare, electronic reconnaissance and analysis, over-the-horizon targeting, missile attack and aerial tanking.’ Naturally, the Viking was furnished with state of the art electronics and tracking equipment and could carry more than 2 000 kg of bombs, missiles and torpedoes. The sea-search radar for example, had a range of 280 km. Even so, the Viking had a compact design and was powered by General Electric J-34 engines, similar to those used by A-10 Thunderbolt II ‘tankbusters’. Its crew consisted of two pilots, a tactical coordinator and a sensor operator, who were seated on ‘zero-zero’ ejection seats.

In contrast with its predecessor, no Vikings were exported and the USN remained its only military operator. During the Gulf War of 1990 to 1991, USN Vikings served as airborne tankers, conducted electronic warfare, attacked Iraqi ground targets and helped with the coordination of large strike missions. According to legend, one Viking pilot bombed an enemy patrol boat with an in-flight refuelling pod, when he accidentally released it along with his bombs. All the same, Vikings were workhorses in combat situations. They were also used extensively during subsequent operations in the Middle East and served over the Balkans and Afghanistan. After more than three decades of service with the USN, the last Vikings were retired in January 2009. According to Ray Burick, Lockheed Martin vice president of S-3 programmes, “The Viking has played a critical role in carrier-based anti-submarine and anti-surface warfare, as well as overland operations, refuelling, targeting, and electronic surveillance. The S-3 Viking will long be remembered for its mission capability, its flexibility and its reliability.”

With memories of the Cold War quickly fading, submarines are no longer seen as a major threat. Nevertheless, that is not the end of the Viking story. Today, NASA (National Aeronautics and Space Administration) operates the last Viking. According to the space administration, “NASA’s S-3B Viking is equipped to conduct science and aeronautics’ missions, such as environmental monitoring, satellite communications testing and aviation safety research. It can fly up to 40 000 feet high and reach speeds in excess of 500 miles per hour, which makes it perfect for studying commercial airline safety issues. This is an all-weather military aircraft. It was built to complete missions in any weather on only one engine if it has to. It is a very capable aircraft in this environment. No other aircraft in the world has the capabilities to perform this ice crystal flight research. With its unique icing cloud measurement instrumentation, robust framework, speed and onboard electrical power system, the S-3B is a tremendous asset for improving aviation safety.”

This article was written by Divan Muller and was first published in African Pilot Magazine in 2010 - www.africanpilot.co.za