The Aero L-39ZO Albatros is a two-seat jet trainer equipped with a turbofan powerplan developed in Czechoslovakia by Aero Vodochody.
During the 1960s, the L-39 Albatros was designed by an Aero Vodochody team under Jan Vlcek as a successor for the Aero L-29 Delfin for
use as a principal training aircraft by the 'Warsaw Pact' countries, as well as the USSR and Soviet allies elsewhere. There was substantial
interest from the Czechoslovak air force for the new trainer, allowing development to go forward. Five prototypes plus two static test
airframes were built (L-39X-01 – X-07). On 4 November 1968, L-39 'Prototype X-02' OK-32 powered by a Soviet-built Ivchenko AI-25V turbofan
was flown first. Following successful flight trials of the prototypes, ten pre-production aircraft were built and with deliveries beginning
in 1971. The pre-production aircraft powered by an Ivchenko AI-25V turbofan were similar to the prototypes, but had bigger air intakes and
slightly longer air intake trunks. The cockpit of the L-39 has twin canopies, both canopies opening to the right. The two seats are separated
by an internal windscreen. Production of the L-39 was initiated in 1972, with service trials the following year and volume deliveries beginning
in 1974. The Aero L-39 was continually developed and improved and exported to a wide range of countries as a military trainer. The Aero L-39ZO
is a training and multi-purpose light attack aircraft, with a reinforced wing and four stores pylons. The "Z" stands for "Zbrojni / Armed". In
initial engineering studies, the variant was assigned the designation 'L-39D'. Initial flight was on 25 August 1975. Production of the L-39 ended
in 1997, with 2.892 airframes built, including 2,081 L-39C for the Soviet Air Force. The ICAO Aircraft Type Designator for the L-39 is L39.
Skyline Aviation B.V. is is an aviation maintenance and operational company that works for Army, Airforce and Marines.
Skyline Aviation was established in 1990 at Den Helder Airport in the Netherlands. Today, the head office of Skyline Aviation is located in Bosschenhoofd;
Groningen Airport Eelde is the home base. Operating from home base Groningen Airport Eelde, Skyline uses the L-39 Albatros and the missionized Learjet 36A.
Skyline Aviation operates one missionized Learjet 36A,we support the Dutch defense with various high-performance aircraft. The tasking consists of supplying
Close Air Support, radar jamming and simulation, target towing, radar tracking profiles and fulfilling the aggressor role during exercises in the Netherlands and abroad.
On 28 November 1977, the 1977-built Aero L-39ZO variant ZO4 s/n 731021 entered service with FAG-25
(Fliegerausbildungsgeschwader 25) as '158' at Bautzen in the Deutschen Demokratischen Republik. In autumn 1989, the
'158' moved to Rothenburg. After German reunification in 1990, the Luftwaffe assumed control over the NVA
equipment and the German Air Force code '28+17' was alloted for GDR's Aero L-39ZO '158'. On 27 July 1994, after
after the aircraft was stored already for a longer period, the Aero L-39ZO ´28~17´ was handed over to the Schwabisches
Bauern und Technikmuseum in Eschach. This museum was not realy an aviation museum and in 1996 the aircraft was
sold to Skyline Aviation. The airframe was not in airworthy condition and was stored. After the L-39ZO underwent a major
overhaul and was brought back in airworthy condition, it was registered ES-TLE with Skyline Aviation, based at Den Helder
Airport in the Netherlands. On 2 May 2018, the aircraft was registered N139LE in the US with FSA Aerospace Inc Trustee,
Wilmington, DE, with as before Skyline Aviation as the real owner of the Aero L-39OZ. As the aircraft is registered as
experimental, Skyline Aviation has painted registration NX139LE on the aircraft instead of the assigned registration N139LE.
On 12 March 2022, the Skyline Aviation' Aero L-39ZO Albatros NX139LE was seen at Groningen Airport Eelde.