Aero L-39NG Skyfox (c/n 167017, ´0478´ of Centrum Leteckého Výcviku / Flight Training Centre – CLV) taking-off for flying display during the 33rd Aviatická pouť (Aviation Fair) air show, Pardubice, June 2025.
Search for a successor of Aero L-39 Albatros, the popular Czechoslovak jet trainer from the Cold War era, began already in the late 1980s. Within the next two decades, a few new aircraft, based on the L-39 successful concept were designed. However, their development was ended at the prototype stage, as was the case of L-39MS / L-59 SuperAlbatros, or resulted in a low-volume produced aeroplane known as L-159 ALCA.
In the early 2010s, the Aero company made another attempt to create the new and up-to-date training jet. Initially, development of an aircraft based on the aforementioned L-159 was planned. The new project, designated L-169 Advanced Training Jet, was announced in 2013 but soon got abandoned.
Nevertheless, as soon as the next year, Aero revealed its new design, the L-39NG (Next Generation). In July of 2014, the new aeroplane was for the first time disclosed to public at Farnborough Airshow. Over the next couple of months, the Czech aviation manufacturer concluded partnership agreements with Draken International and Williams International to jointly develop the new training jet.
The L-39NG development project was split into two stages. Firstly, there was an aircraft designated L-39CW – a jet trainer based on the L-39C Albatros airframe but re-equipped with modern Williams FJ44-4M jet engine and updated avionics suite. On 14th September 2015, the L-39CW prototype successfully performed its first flight. The aircraft was mainly aimed for current operators of the Albatros trainers who were in need of modernisation of their L-39 fleet, but at the same time did not have enough budget to purchase a completely new aircraft.
On 22nd December 2018, prototype of the second stage aeroplane, the L-39NG, performed its maiden flight.
Although silhouette of the new aircraft resembles its predecessor, the L-39NG is a completely new construction. Its airframe is made with use of composite materials for lower weight and better durability. The L-39NG is also equipped with larger cockpit featuring digital flight instrument displays and head-up guidance system, as well as new canopy.
What distinguishes the new aircraft from its predecessor are the wings that lack of wingtip fuel tanks, typical for the L-39 Albatros family. The reason is the L-39NG wings are made in ´wet wing´ technology, featuring integrated fuel tanks. In addition, the new trainer has a shorter nose and smaller engine intakes. Similarly to the L-39CW, the L-39NG is powered by Williams FJ44-4M jet engine.
According to the official information from the manufacturer, the L-39NG can operate from unpaved runways and has a service life of up to 15,000 flight hours. The aircraft can also be used in reconnaissance and light attack missions, as it features up to five hard points for weapon systems.
Although serial production of the new aircraft began already in February 2019, the development of the L-39NG began to suffer from delays, caused by overall situation on the aviation market and changes in the company ownership. At some point, it seemed the Czech Ministry of Defence would be the only customer for the new training jet.
In 2021, Aero Vodochody was acquired by new owner, HSC Aerojet Zrt., and the L-39NG development entered full swing. In February of the same year, the aircraft got its first customer – the Vietnam Air Force that ordered twelve aeroplanes. In April of 2022, another twelve L-39NGs were ordered by Hungarian Air Force and, in November of that year, the LOM Praha state company ordered four aircraft for its CLV in Pardubice. Interest in the new jet trainer was also expressed by the Slovak Ministry of Defence but no final decision was made yet.
In October of 2024, the L-39NG was officially named Skyfox.
The Vietnamese L-39NGs were delivered until March of 2025, the first aircraft for CLV Pardubice and the Hungarian Air Force were delivered in February and May of 2025, respectively.
In June of 2025, during the 33rd edition of Aviatická pouť air show, CLV Pardubice for the first time presented its new L-39 Skyfox for general public. The aircraft performed a joint flying display with LET C-11 training aircraft from the 1950s, as well as was available at the static display.
