http://www.hisutton.com/CosMoS CE4F SDV.html The CE4F was the last and most secret Swimmer Delivery Vehicle (SDV) built by the famed manufacturer Cos.Mo.S based in Livorno, Italy. Within naval circles Cos.Mo.S were well known for their CE2F two-man chariots which were widely exported from the 1960s until ~2000. Sales brochures and photographs of the CE2F were widely distributed and many books discussed them as the classic Cold War western SDV alongside the SEALs’ SDV Mk8. The follow-on CE4F however was barely reported: the original customer, and only known operator, was the Turkish SAT (Su Altı Taarruz) Special Forces. It is only in Jan 2017 that the existence of the SAT version has been made public when an example was given to Yildiz Teknik University (WEBSITE). The CE4F was designed for the Turkish Navy's elite Special Forces SAT (Su Altı Taarruz) which is generally equivalent to the US Navy SEALs and has a history of using Cos.Mo.S submersibles. The new craft had to be non-magnetic with a relatively up to date electronics fit including internal navigation, obstacle avoidance sonar, autopilot and folding optronics mast. Description In building an up-to-date four-man SDV, Cos.Mos.S deviated from the classic in-line crew arrangement of their earlier designs. At first glance the smooth lines of the craft resembled the prototypical US made SDV Mk.8, but the more torpedo-like with a circular cross-section and ducted prop at the rear. It was actually similar in dimensions to the previous generation CE2F except in width, which would potentially allow it to be carried externally by midget submarines in a similar manner to the two-man chariots. The divers sat in a 2 x 2 layout, all facing forward like in a car. It was not entirely new however; the battery compartment, which was buried inside the streamlined GRP (glass reinforced plastic) fuselage, was actually very similar to the one in the older CE2F. But the major similarities ended there. The layout was unique among SDVs, with the battery compartment and variable stores (mines, torpedoes, Special Forces stores) in the nose, and the crew almost at the back of the craft. Specification Length: 8.55m (28ft) Beam: 1.475m (4.6ft) Displacement: 4.05 tons Weight (in air): 3.85 tons Speed: 7.5 kt max, 6 kt cruising Operating depth: 60m (180ft) Max depth: 100m (300ft) Range: 30 nm Crew: 4 swimmers Armament/payload: 1 large mine or stores container. 8 mini-torpedoes. Sensors: Optronics mast, INS (internal navigation system), autopilot, OAS (obstacle avoidance sonar). Fate As well as the inherent secrecy surrounding Special Forces projects at the time, the deal came at a difficult time for the company. It was under the leadership of international arms dealer Carlos Cardoen who had replaced the Italian founder Ing Pucciarini. Cardeon was willing to supply arms to sanctioned countries including Iraq under Saddam Hussein, and even tried to sell the entire Cos.Mo.S company to him. Eventually in the early 2000's the Italian Government stopped the Iraqi deal and, combined with other sour deals, the company defaulted. Cardoen was subject to an international arrest warrant but evaded capture. The prototype CE4F however lived on in Turkey and is now on display at the university. Subsequent development is unclear.