The first L-39NG prototype, 2626, is a former Ukrainian Air Force L-39C bought back by Aero Vodochody for use as a company development aircraft.
The first L-39NG prototype seen during its first flight powered by the newly-installed FJ44-4M engine on September 14, 2015.
The L-39ZA version, developed in the late 1970s, was designed for use as both trainer and light attack aircraft.
The Williams International FJ44-4M offers the same 3,790 lb (16.87 kN) maximum thrust rating as the AI-25TL, but is lighter and boasts a much better response time; its acceleration from idle to maximum power setting is between three and five seconds versus nine to 12 seconds for the AI-25TL.
The L-39C, the first production standard of the Albatros, is still in use worldwide with many military and civil operators. This is an example operated by the Slovak Air Force, one of the three remaining European/NATO operators for the type, together with the Czech and Bulgarian air forces.
The L-39ZA is an armed version, with a GSh-23L gun-pack under the fuselage.
A look into the L-39ZA's cockpit, packed with conventional analogue instruments and a marked contrast to the cockpit of the L-39NG.
A computer-generated image of the L-39NG.