Quantity production of the L-39 Albatros proceeded in 1971; one year later, it was formally recognized by the majority of the Warsaw Pact countries as their preferred primary trainer.

During 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.

[2] 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.

[12] 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.

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; 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.

[2] 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.

[17] 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.

[18] 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 (Skyfox), to compete with the Alenia Aermacchi M-346 and British Aerospace Hawk.

The L-39 Skyfox 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.

For operational flexibility, simplicity, and affordability, the majority of onboard systems have been simplified to avoid incurring high levels of maintenance, as well as to minimize damage caused by mishandling when flown by inexperienced air crew.

Operational g-force limits at 4,200 kilograms (9,300 lb) are +8/-4 g.[24] A long, pointed nose leads back to the tandem cockpit, in which the student and instructor sit on Czech-built VS-1 ejection seats under individual canopies, which are opened manually and are hinged on the right.

[25] The rear seat, typically used by the instructor, is elevated slightly to readily enable observation and guidance of the student's actions in the forward position.

[24][26] The design of the cockpit, panel layout and many of its fittings resemble or are identical in function to those of other commonly used Soviet aircraft; for example, the procedure for deploying the ejection seat is exactly the same as for the Mikoyan MiG-29.

[29] A single turbofan engine, an Ivchenko AI-25TL (made in the Soviet Union) is positioned in the rear fuselage, fed through shoulder-mounted, semi-circular air intakes (fitted with splitter plates) just behind the cockpit and the tailpipe below the horizontal tailplane.

Several heavy radio units are typically installed in an aft avionics bay; these are often removed on civilian-operated aircraft and replaced with a 70-gallon fuel tank.

[41] The newly de facto independent Chechen Republic of Ichkeria found itself with dozens of L-39s (as well as several L-29s, three MiG-17s, two MiG-15UTIs, helicopters and other transport and civilian aircraft) left at Khankala and Kalinovskaya airbases by the Soviet Air Force in 1992.

[8] By mid 1970, the Iraqi Air Force had procured a considerable number of L-39 trainers, having transferred the bulk of their training activities onto the Czechoslovak aircraft.

[45] During the American-led invasion of Iraq in 2003, on 14 April 2003, a pair of United States Navy McDonnell Douglas F/A-18 Hornets attacked several L-29 and L-39 aircraft on the ground at an airfield near the city of Tikrit; these had been believed to have been modified to perform as delivery platforms for weapons.

[48] In the midst of that conflict, on 21 April 1983, three LARAF Ilyushin Il-76TDs and one Lockheed C-130 Hercules landed at Manaus Airport, Brazil after one of the Il-76s developed technical problems while crossing the Atlantic Ocean.

The aircraft were then searched by the Brazilian authorities: instead of medical supplies – as quoted in the transport documentation – the crate of the first of 17 L-39s bound for Nicaragua together with arms and parachutes, to support the country's war against US-backed Contras, were found.

[51] Following the dissolution of the Soviet Union and the formation of the Russian Air Force in 1991, the newly formed service found itself with hundreds of L-39 aircraft, the majority of which were surplus to their training requirements.

According to author Stephan Wilkinson, by 2005, Russia was seeking to potentially sell up to 800 of their L-39s, which were receiving only a basic level of maintenance once per month while their fate was being decided.

[64] According to Reuters, by 2014, the L-39 had allegedly become one of the favoured platforms of the Syrian Air Force for performing ground attack missions due to its slower speed and higher agility over other aircraft in its inventory.

In December 2015, following the securing of the Kweiris airbase by government forces, the resumption of ground-attack missions by L-39s in the vicinity of Aleppo commenced shortly thereafter.

Among those killed was combat pilot Andrii Pilshchykov, an Order of Courage recipient more commonly known by his callsign "Juice", who had become famous in the west for his articulate appeals early in the war for allies to supply F-16s to Ukraine.

[26] This trend is particularly evident in the United States, where their $200,000–$300,000 price puts them in range of moderately wealthy pilots looking for a fast, agile personal jet.

[73] Their popularity led to a purely L-39 Jet class being introduced at the Reno Air Races in 2002, though it has since been expanded to include other, similar aircraft.