In 1964, Czechoslovak aircraft manufacturer Aero Vodochody embarked on a new design project to meet the specified requirements for a "C-39" (C for cvičný – trainer), setting up a design team under the leadership of Jan Vlček.
This aircraft was to serve as a replacement for the Aero L-29 Delfín, an early jet-powered trainer, as a principal training aircraft.
Vlcek envisioned the type, a twin-seat single-engine aircraft, being adopted as the primary trainer throughout the Warsaw Pact nations.

On 4 November 1969, the L-39 (under the designation "Prototype X-02" – the second airframe to be built) conducted its maiden flight, for which it was piloted by Rudolf Duchoň, the factory's test pilot.
Serial production of the initial model of the L-39, designated L-39C, commenced in 1971.
In 1972, the L-39 Albatros was formally recognized by the majority of the countries comprising the Warsaw Pact as their preferred primary trainer, after which point, sizable orders from military customers throughout the bloc proceeded, many of which were from the Soviet Air Forces.
In 1974, the first L-39 trainer entered service with the Czechoslovak Air Force.

Several specialised variants of the base L-39 design were quickly introduced.
In 1972, a purpose-built target tug variant, the L-39V, conducted its initial flight.
In 1975, the first L-39ZO training/light combat model, which was equipped with four underwing hardpoints as well as a strengthened wing and modified landing gear, performed its first flight.
In 1977, the first L-39ZA light combat variant, which was fitted with a single Gryazev-Shipunov GSh-23 cannon mounted underneath the fuselage in addition to the four hardpoints and strengthening of the L-39ZO, made its maiden flight.

According to aerospace publication Flight International, roughly 200 L-39s were being sold each year upon the jet trainer market during the late 1980s.
According to the Stockholm International Peace Research Institute, in 1993, the total export orders gained for the L-39 represented 80 per cent of the value of all Czech military product export sales made for that year.
During the 1990s, shortly following the dissolution of the Soviet Union and the end of the Cold War, Aero Vodochody decided to develop versions of the Albatros equipped with Western-sourced avionics, engines, and weapon systems.
Around the same time, Aero Vodochody formed an active partnership with Elbit Systems of Israel, under which a number of L-39s were delivered to Elbit to be equipped with modern electronics and onboard systems before being re-exported to end users such as the Royal Thai Air Force.

Sales of the L-39 declined during the 1990s.
This downturn has been attributed to the loss of the captive Warsaw Pact trainer market, to which a substantial proportion of the total aircraft manufactured had been historically sold to; allegations about Czechoslovak banks being unable to finance the defense industry and inaction on the part of the Czechoslovak government; and concerns over the quality of manufacturing standards.
In 1996, production of the L-39 came to an end.
Since the end of production, Aero Vodochody has developed several improved variants of the L-39 to take its place, and has continued extensive support and overhaul operations for existing L-39 customers.

One of the replacements for the L-39 Albatros was the Aero L-159 Alca, a modernised version of the L-39.
Originally, Aero Vodochody had intended to develop the L-159 in partnership with Elbit, but the Czech Ministry of Defense instead selected Rockwell Collins to partner on the program.
The limited success of the L-159 led Aero to announce at the 2014 Farnborough Airshow that it was developing an upgraded version of the L-39, designated L-39NG, to compete with the Alenia Aermacchi M-346 and British Aerospace Hawk.
The L-39NG replaces the AI-25 turbofan with a Williams FJ44 engine; the airframe is modified, the wingtip fuel tanks being eliminated, and a new suite of avionics will be provided.
First flight of the L-39NG was in September 2015, with deliveries starting in 2020.
In 1964, Czechoslovak aircraft manufacturer Aero Vodochody embarked on a new design project to meet the specified requirements for a "C-39" (C for cvičný – trainer), setting up a design team under the leadership of Jan Vlček. This aircraft was to serve as a replacement for the Aero L-29 Delfín, an early jet-powered trainer, as a principal training aircraft. Vlcek envisioned the type, a twin-seat single-engine aircraft, being adopted as the primary trainer throughout the Warsaw Pact nations.
On 4 November 1969, the L-39 (under the designation "Prototype X-02" – the second airframe to be built) conducted its maiden flight, for which it was piloted by Rudolf Duchoň, the factory's test pilot. Serial production of the initial model of the L-39, designated L-39C, commenced in 1971. In 1972, the L-39 Albatros was formally recognized by the majority of the countries comprising the Warsaw Pact as their preferred primary trainer, after which point, sizable orders from military customers throughout the bloc proceeded, many of which were from the Soviet Air Forces. In 1974, the first L-39 trainer entered service with the Czechoslovak Air Force.
Several specialised variants of the base L-39 design were quickly introduced. In 1972, a purpose-built target tug variant, the L-39V, conducted its initial flight. In 1975, the first L-39ZO training/light combat model, which was equipped with four underwing hardpoints as well as a strengthened wing and modified landing gear, performed its first flight. In 1977, the first L-39ZA light combat variant, which was fitted with a single Gryazev-Shipunov GSh-23 cannon mounted underneath the fuselage in addition to the four hardpoints and strengthening of the L-39ZO, made its maiden flight.
According to aerospace publication Flight International, roughly 200 L-39s were being sold each year upon the jet trainer market during the late 1980s. According to the Stockholm International Peace Research Institute, in 1993, the total export orders gained for the L-39 represented 80 per cent of the value of all Czech military product export sales made for that year. During the 1990s, shortly following the dissolution of the Soviet Union and the end of the Cold War, Aero Vodochody decided to develop versions of the Albatros equipped with Western-sourced avionics, engines, and weapon systems. Around the same time, Aero Vodochody formed an active partnership with Elbit Systems of Israel, under which a number of L-39s were delivered to Elbit to be equipped with modern electronics and onboard systems before being re-exported to end users such as the Royal Thai Air Force.
Sales of the L-39 declined during the 1990s. This downturn has been attributed to the loss of the captive Warsaw Pact trainer market, to which a substantial proportion of the total aircraft manufactured had been historically sold to; allegations about Czechoslovak banks being unable to finance the defense industry and inaction on the part of the Czechoslovak government; and concerns over the quality of manufacturing standards. In 1996, production of the L-39 came to an end. Since the end of production, Aero Vodochody has developed several improved variants of the L-39 to take its place, and has continued extensive support and overhaul operations for existing L-39 customers.
One of the replacements for the L-39 Albatros was the Aero L-159 Alca, a modernised version of the L-39. Originally, Aero Vodochody had intended to develop the L-159 in partnership with Elbit, but the Czech Ministry of Defense instead selected Rockwell Collins to partner on the program. The limited success of the L-159 led Aero to announce at the 2014 Farnborough Airshow that it was developing an upgraded version of the L-39, designated L-39NG, to compete with the Alenia Aermacchi M-346 and British Aerospace Hawk. The L-39NG replaces the AI-25 turbofan with a Williams FJ44 engine; the airframe is modified, the wingtip fuel tanks being eliminated, and a new suite of avionics will be provided. First flight of the L-39NG was in September 2015, with deliveries starting in 2020.
Aero L-39 Albatros