TAI's firefighting aircraft project: S-2E/T

In the late 1940s, the US Navy decided it needed a new anti-submarine aircraft to replace the AF2s. Grumman company responded to this demand with the two-engine, overhead-wing G-89 model. Among the requirements of the aircraft to be produced were sensors (sensors) and a high load capacity that allows it to carry weapons, a radar that can be pulled into the fuselage, magnetic detectors and search projectors. In order to be able to be deployed on aircraft carriers, the wings of the aircraft were required to be foldable and the tail hook attached.

This two-engined aircraft (prototype XS2F-1) successfully performed its first test flight on 4 December 1952. The first mass-produced aircraft, the S-2A, entered service with the US Navy in February 1954 as an anti-submarine warfare (DSH) aircraft. More than 500 aircraft were produced from S-2As and delivered to the US Navy and some allied countries.

Other models are the S-2C (with enlarged arsenal, produced with a larger tail design to accommodate the increased weight), US-2A/B/C (light transport and target towing aircraft modification of the S-2), RS-2C (Photo- reconnaissance model), S-2D (with increased wingspan, larger tail, four crew, enlarged cabin and increased sonoboy payload), S-2E (Model with enhanced search equipment), S2F (modified S-2B), CS-2F/ CP-121 (model manufactured by DeHavilland for the Canadian Navy) and S-2G. The S-2 Hawkeye early warning aircraft equipped with the APS-82 early warning search radar mounted on the fuselage radoma was also later included in the inventory. A total of 1 181 aircraft were produced from different models of the S-2.

The US navy used S-2 E/G aircraft, stationed on aircraft carriers, as DSH aircraft against submarine attacks between 1954-1972. In addition, it effectively kept the early warning and electronic warfare aircraft (E-2C Hawkeye) deployed on aircraft carriers in its inventory as a Navy aircraft for many years.

Evaluating the retirement of S-2 aircraft by the US Navy, the Turkish Navy added 4 S-2A aircraft to the inventory of the 301st Naval Air Fleet Command, which was established in Etimesgut/Ankara on October 18, 1971. These four planes were purchased for the purpose of training the pilots who will use the S-2 planes to be purchased later. In 1972, 12 S-2E aircraft, which were taken out of service by the Dutch Navy, were taken into the inventory of the 301st Fleet, and a total of 16 S-2 aircraft were given to the fleet. The fleet, which continued its training in Etimesgut until August 4, 1972, then transferred to Bandırma Air Base. In 1976, the fleet finally transferred permanently to Cengiz Topel Square, where it is now stationed.

S-2 aircraft performed their duties with 4 crews (two pilots, two technicians/operators) as DSH/DK (Marine Patrol) aircraft. During the DSH/DK duties, the pilot sitting in the left seat was responsible for flying the aircraft safely, while the one sitting in the right seat was responsible for fulfilling the tactical operations requirements together with the technician/operator. S-2E aircraft were deployed at the Cengiz Topel Naval Air Base Command and used in line with the operational needs of the Naval Forces. The Naval Forces evaluated that these aircraft, whose maintenance-maintenance became quite problematic over the years, came to the end of their economic and technological life, started to end the use of the aircraft as of 1993, and removed all S-2s from the inventory in 1995.

Meanwhile, in the 1970s, the California Department of Fire Protection (CAL FIRE) purchased the S-2A models of these aircraft from the US Navy and converted them into firefighting aircraft and started to use them. CAL FIRE later purchased 26 S-2E/G aircraft from the US Department of Defense in 1996 to convert them into firefighting aircraft. In order to use these aircraft as firefighting aircraft, CAL FIRE has implemented a modernization program on the aircraft. Within this framework, the engines of the aircraft were replaced with more powerful and modern engines. Modified S-2s have been made faster, safer and highly maneuverable aircraft. A water intake chamber with a volume of 4.540 liters was added to the aircraft. With the new fire configuration, S-2s started to be used in firefighting missions as the most essential aircraft of the CAL FIRE firefighting fleet. CAL FIRE, which has gone through engine revision since 1985, has made all S-2s turboprop as of 2005. CAL FIRE continues to use its 23 S-2T aircraft in aerial firefighting missions together with other aircraft.

Considering the successful role these aircraft play in firefighting missions in the CAL FIRE fleet, Türk Aerospace Sanayii A.Ş. (TUSAŞ) (at that time Turkish Aerospace Industry – TAI), known for modernizing S-2 aircraft since the 1980s Collaborating with the US firm Marsh Aviation, with the support of the TEMA foundation, it has rolled up its sleeves to transform the S-2E aircraft, which were retired by the Turkish Navy, into firefighting aircraft. In this context, a project to convert one S-2E aircraft into a fire extinguisher aircraft was initiated in 1996. In 1997, we signed a contract with Marsh Aviation and worked together. In this context, the S-2E aircraft was converted into a firefighting aircraft. The method was based on CAL FIRE modernization, in a way “America has not been rediscovered.” Turbo engines were installed on the prototype aircraft. The name of the aircraft was determined as "TEMA".

Evaluating that the Ministry of Agriculture and Forestry is not willing to create its own aerial firefighting aircraft fleet and has adopted the leasing method, TAI has predicted that it can convert a total of 15 S-2E aircraft into firefighting aircraft and offer them to the Turkish Aeronautical Association (THK). THK, which served the General Directorate of Forestry with the Dromader fire extinguishing aircraft in its inventory at the end of the 1990s, could not reveal the willingness and will to aspire to the S-2 aircraft for various reasons.

If the prototype aircraft solution proposed by TAI is accepted, it has been calculated that each aircraft can be converted into a firefighting aircraft at a cost of approximately 3 million USD. It has been calculated that the total project cost will be 40-45 million USD in 1998 figures. If the project is approved, it is envisaged that the project will be completed in 20 months in total, and that these aircraft, which have been modified with new engines and structural improvements, will continue to serve as firefighting aircraft for 20 more years from 2000 (until today).

TUSAŞ, which has not completely given up hope on the Turkish Aeronautical Association, performed important flight missions with its prototype S-2E/T (Tracker) aircraft in extinguishing the fire in the TÜPRAŞ refinery, which started after the 1999 earthquake. The aircraft was also used for aerial response to forest fires near Antalya. Thus, the S-2E/T prototype aircraft has undergone a successful real “flight test” in the field as an aerial response to forest fires.

Retired Air Pilot Lieutenant General Sinan Bilge, Chairman of TAI at the time, expressed the project about the S-2E/T aircraft in a television program (TRT1 Haber 24 program, 17 October 1997) as follows: “Forest fires inflict great damage on Turkey every year. . There is an inadequacy in land interventions. We will transform our 15 aircraft, which were taken out of the inventory of the Naval Forces Command, into firefighting aircraft… We have seen that these aircraft have been converted into firefighting aircraft in Canada, France, America, Argentina and South Africa. As TAI, we evaluated whether we could use S-2E Tracker aircraft. We met with our Minister of Forestry, Ersin Taranoğlu, and he was satisfied. We brought two aircraft developed by Canadians to Turkey. They will make demonstration flights in Ankara today. If the Ministry approves, we will gain 15 aircraft (to Turkey). This is a national solution. We can use (these planes) for a minimum of 20 years after conversion…”

Despite all the persistent efforts and initiatives of TAI management, the failure of this project to be realized, as stated by the engineers/technicians working at the factory in those years, caused disappointment in the factory personnel.

TUSAŞ, which could not receive the necessary support from the General Directorate of Forestry and the Turkish Aeronautical Association, had to cancel its fire extinguishing aircraft project in 2000, which was in a way unclaimed. The fact that the 15 S-2 aircraft, which the Naval Forces Command is ready to transfer directly to the user authority without any charge, is a "national" transformation project to be carried out by the Turkish people, could not be realized because the bureaucratic structure within the state wheel did not adopt the subject sufficiently. In these years when the F-16 production line was almost empty, the possibility of transforming S-2 aircraft into fire aircraft, which was seen as an exciting project for all factory personnel, disappeared in the early 2000s.

As a result, nine of the S-2 aircraft, which the Naval Forces Command kept in order to convert them into firefighting aircraft, were sold to the Machinery and Chemical Industry Corporation (MKEK) as "scrap material". One S-2 aircraft was delivered to the Air Force Command to be exhibited at the Yesilyurt (Istanbul) Air Museum.

The S-2 prototype aircraft in TAI, which did not even fly for a while, was re-started as a flying test platform with the decision taken by the TAI management in 2009. It is envisaged that this aircraft will be used in a way that will meet the needs of other Turkish defense industry companies, as well as the needs of TAI, and in this direction, the fire extinguishing kit on the aircraft has been removed and it has been turned into a flying test platform. It fulfills the airworthiness requirements and performs its flights with special permissions given by the General Directorate of Civil Aviation (SHGM) as a test platform. 

The tail number of the S-2E/T aircraft, which was registered by DGCA, was changed to “TC-STF” registered by DGCA in 2014. TC-STF continued its flights in line with the needs. This aircraft continues to be used as a test platform by TAI and to serve the demands of defense industry companies when necessary, despite some maintenance-maintenance and parts support problems (despite receiving partial support from CAL FIRE). The author of these lines had the chance to perform a few sorties with the S-2E/T flying test platform during his time at TAI. This aircraft, which is very pleasant to use and provides a stable flight with its classic flight controls, has reached the end of its useful life as of 2021. After a new flying test platform aircraft to be taken to TAI in the near future, a nostalgic airplane that should take its place in the TAI aviation industry museum and that will make its visitors love aviation with its "smiling face" as the prototype airplane of the project to transform it into a fire extinguishing aircraft successfully implemented by TAI. It is expected that he will continue to do his duty.

Today, as all members of this nation, we are suffering the consequences of the absence of fire extinguishers in Turkey, which is a country of forest fires. If the project of converting S-2 aircraft into fire aircraft, which was initiated by TAI, had been adopted by the relevant organs of our state and/or the management of the Turkish Aeronautical Association of the time, we could have had a fleet of 15 S-2E/T aircraft that we can use against fires today. In addition to these aircraft, we think that our firefighting fleet, which will be further strengthened with CL-215 aircraft, which later joined the inventory of the Turkish Aeronautical Association, would undoubtedly enable us to have a better position against forest fires than we are in today.

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