The SIAI-Marchetti SF.260 (now Leonardo SF-260) is an Italian light aircraft which has been commonly marketed as a military trainer and aerobatics aircraft.
The SF.260 was designed by Italian aircraft designer Stelio Frati, while production work was originally performed by Milan-based aviation manufacturer Aviamilano. On 15 July 1964, the first prototype performed its maiden flight (then designated F.260). Shortly thereafter, responsibility for production was transferred to SIAI Marchetti, who had purchased the rights to the design; manufacturing continued to be performed by this firm until the company was bought by Aermacchi in 1997.
The SF.260 has been largely sold to military customers as a trainer and light combat aircraft. In addition, there have been limited civil sales to private operators; during the late 1960s, the type was marketed in the United States under the name Waco Meteor. Armed military versions, sold as the SF.260W Warrior, proved to be popular with smaller air forces, which could arm the type for use in the close air support role. Both piston-powered and turboprop-powered models have been developed.
Development Origins During the early 1960s, Italian aircraft designer Stelio Frati commenced work on a new three-seat aerobatic design, which was primarily intended to serve as a sport aircraft. Unlike many of its peers of the era, it was developed to possess aerobatic capabilities akin to contemporary combat aircraft, as well as being equipped for instrument flight rules (IFR) flight. This design drew heavily upon his previous projects, including the jet-powered Caproni Trento F-5 prototype trainer and the Falco F8L twin-seat aerobatic aircraft, sharing the same wing and a similar structure to the Falco. The envisioned aircraft, initially designated as the F.250 due to the horsepower of its engine, was Frati's first all-metal aircraft.
On 15 July 1964, the type performed its maiden flight. In the aftermath of the maiden flight, prime responsibility for the type's manufacture was acquired from Aviamilano by SIAI Marchetti, which had purchased the rights to the design outright. Shortly after entering production, the SF.260 found itself in high demand by military customers, who often adopted it interchangeably as a military trainer or as a lightweight ground-attack aircraft. Between 1964 and 1984, the majority of customers for the type were military, while a small number of private pilots had been able to obtain a few, although supply in this respect was constrained.
During the late 1960s, the aircraft was marketed in the United States market as the Waco Meteor, although it had no connections of any form with the Waco Aircraft Company; the venture was relatively unsuccessful.. During the late 1970s and 1980s, American airline pilot Frank Strickler became a major reseller of the type, being credited with re-launching civil sales of the SF.260 in the region, acquiring them from SIAI Marchetti in small batches and individually selling them on to US-based customers.
Further development During the late 1970s, an improved model of the SF.260A, designated as the SF.260C, had replaced it in production. This model featured various improvements, including redesigned tabs on the ailerons, a strengthened wing, a re-profiled aerofoil for improved low-speed handling, and an elongated tail/rudder. The SF.260C was designed for compliance with the requirements of military specifications. The only structural difference between the SF.260C and its armed brethren, the SF.260W Warrior and SF.260SW Sea Warrior, is the presence of underwing hardpoints for attaching equipment and armaments.
During 1980, SIAI Marchetti performed the first flight of a turboprop-powered SF.260TP, powered by an Allison Model 250 engine flat-rated at 350 shp. This variant was marketed towards the military trainer market, which soon adopted the type. In August 1986, Gates Learjet was approached by SIAI Marchetti to modify the SF.260TP for it to be compliant with the requirements of Federal Aviation Administration's (FAA) FAR Part 23, thus allowing it to be certified for civil use. Modifications were made in order to achieve lower stall speed and greater payload capacity, these performance improvements were principally achieved through aerodynamic alterations, such as the adoption of 'shark's teeth' along the wing's leading edge.
In 1991–1992, SIAI-Marchetti proposed an updated SF.260, with an enlarged cockpit canopy and a revised fuel system to meet the United States Air Force's Enhanced Flight Screener competition. While the bid was unsuccessful (with the Slingsby T67 Firefly being preferred), it formed the basis for future production, as the fuel injected SF.260E and the normally aspirated SF.260F. During 2005, a batch of thirty SF.260EA were delivered to the Italian Air Force for a total price of €33 million ($40 million).Moloda, Pino. "Italy gets the new SF260EA." Flight International, 16 August 2005. This model, which had been specially developed to meet an Italian Air Force requirement for an advanced piston-engine aircraft, is used for screening and principal training activities.
In 2010 Philippine Aerospace Development Corporation obtained license production for 18 units of SF 260 TP single-engine turbo prop trainer for the Philippine Air Force which were delivered in 2011.
Production of the SF.260 continued at a low rate until 2017. A total of 976 aircraft, including prototypes, were built.
Design
The SIAI-Marchetti SF.260 is a low-mounted cantilever wing monoplane, complete with a retractable tricycle undercarriage. It has been often praised for its sleek lines and sporty aesthetic appearance, while maintaining function as well, possessing jet-like handling as a result. The construction is typically known for having a high level of workmanship, while exterior is extensively flush-riveted to reduce aerodynamic drag, except for a few locations such as the flaps and some fairings. The SF.260 has a compact, dense structure which possesses ballistics similar to a jet aircraft, and is approved to perform aerobatic manoeuvres. In comparison to most single-engine aircraft, it possesses superior power loading and above average wing loading.
The original model of the SF.260 was powered by a single Lycoming O-540 engine, capable of providing 260 hp. The standard engine made use of a carburetor, while a fuel injected engine was available as an optional extra. The SF.260 has been described as having the power to be immune to the gyration-like effects of turbulence and possessing a high rate of climb. During the 1980s, aerospace publication Flying stated the SF.260 to be: "the fastest normally aspirated piston single in production". The SF.260 holds the airspeed records for aircraft in its class over the and closed circuits. Later-built models often made use of turboprop engines; the initial model to be equipped as such, designated as the SF.260TP, was powered by a single Allison Model 250 engine, flat-rated at 350 shp.
The pilot and up to two passengers (or pilot and one student in trainer versions) are accommodated under a broad, extensively glazed canopy. The pilot, who accesses the aircraft via purpose-built walkways along the wing, would be typically seated on the right-hand side of the cockpit; military pilots are trained to control the aircraft using their right hand on the stick and their left on the throttle.
While being a fully aerobatic aircraft, it possesses favourable handling qualities, including relatively tame stall characteristics. Controllability during stalls is augmented by vanes located on the wing tip tanks which accelerate airflow over the tips and ailerons. The SF.260 is a relatively fast aircraft, complete with responsive controls; as a product of the latter, pilots need to maintain awareness of speed dips, although ample aerodynamic warning is typically present. Piston-engined and turboprop-engined SF.260 models generally share similar handling and flight performance. Speed limitations on the landing gear has been highlighted as a negative attribute. In order to safely perform aerobatics, the rear seat has to be unoccupied and the tip tanks must be empty of fuel prior to commencing any such manoeuvers, reducing the SF.260's flight endurance to roughly one and a half hours.
Operational history
Burkina Faso This small air force operated six Warriors these Warriors were sold from the Philippines via Belgium in 1986, and were complemented by other four new Warriors coming directly from Italy, and employed during the Agacher Strip War with Mali in 1986. These aircraft were in service with Escadrille de Chasse ("Fighter Squadron") in the Force Aérienne du Burkina Faso (FABF), the Burkina Faso Air Force.
Chad Chad informed the United Nations that, during the conflict with Libya, it had destroyed eight Libyan Air Force SF.260WLs and captured nine others, besides destroying and capturing other equipment. As many as six former Libyan SF.260WLs may have been pressed into service with Chad's Air Force. By 1988, four SF.260Ws were identified as being in service, two of them were overhauled one year later in France.
In November 2006, Libya supplied Chad with four SF.260W aircraft, including crew, due to tensions between Chad and Sudan over the Darfur area. One newly supplied SF.260W was shot down on 28 November – its first mission in Chad – by rebel forces, killing the crew."Chadian aircraft downed." Taoeil Times, 30 November 2006.
Libya Libya was a major customer of the SIAI Marchetti SF.260 with an order of 240 SF.260WLs. The first 60 aircraft were manufactured in Italy, while the others were delivered as knock-down kits, and assembled in a new plant in Sebha, under the supervision of Italian technicians.
The SF.260WL was intended for pilot training, but was also used for ground support during the war in Chad. Dozens of Italian pilots served as instructors for Libyan cadets from 1977. Their number decreased in 1982, as they were supplemented by a group of 15 Libyan instructors, who had been trained at SIAI Marchetti's facilities in Italy. Libyan SF.260s played an important role during the country's involvement in Chad. They were used as light ground attack aircraft, using machine gun pods, rockets and bombs. Their first known actions took place in February 1978, when they participated in air strikes on the Chadian army garrison of Faya-Largeau together with Mil Mi-25 helicopters. As a result of the sustained bombardment, the majority of the 5,000 troops deployed there fled, and around 1,500 of them were taken prisoners on February 18.
Gaddafi finally succeeded in installing a generally pro-Libyan government in N'Djamena in 1979 (the Transitional Government of National Unity or GUNT). However, the new Chadian defence minister, Hissène Habré, was fiercely anti-Libyan, and immediately started distancing himself from the rest of the government. This culminated in Habré's forces taking N'Djamena on 1 April 1980. Pro-Libyan factions fled to Libya, where they were reorganized and re-armed. These forces came back to Chad in October of the same year, together with the Islamic Legion. Once again, SF.260s were involved in heavy airstrikes on Faya-Largeau, together with Mi-25 helicopters, Mirage 5s and Tupolev Tu-22s. The quasi-continuous bombardment, which lasted for almost a week, had a big impact on the morale of the defenders. Hence, the pro-Libyan GUNT forces easily took control of Faya-Largeau in early November 1980.