LONDON—A lack of training, flying hours and funding have directly contributed to the high level of losses experienced by the Ukrainian air force as it battles Russian troops in the eastern part of the country.
A Ukrainian official, speaking at an event here, said 23 years of independence from the Soviet Union meant that Ukrainian pilots were not experienced flying in combat.
“There is a lack of experience, and we have not had enough money to provide training for our pilots,” the official said.
He also pointed to the passing of intelligence about the level and number of air defense systems, in particular, man-portable launchers currently in the hands of terrorist groups in Eastern Ukraine.
The official said around 20 air defense batteries were currently in operation in Eastern Ukraine, using weapons captured from Ukrainian weapons depots in now-annexed Crimea and transferred east or supplied directly from the Russian Federation. The official said some shoulder-launched missiles were looted by Russian special forces from a public security building in Donetsk.
The Ukrainian air force’s losses have been high. Since the beginning of the year, the air arm has lost 10 helicopters – five Mil Mi-8 Hip transport helicopters and five Mi-25 Hind attack helicopters. It has also lost five Sukhoi Su-25 Frogfoots, two Mikoyan MiG-29s Fulcrums and an Su-24 Fencer. 
Shoulder-launched weapons also downed an Antonov An-26 and An-30 transport, along with one of three Il-76s flying a supply mission into Lughansk, using two missiles fired from two different sites as the transport aircraft made its approach to land.
Ukraine is upgrading its fighters, the majority of which entered service in the late 1980s and early 1990s. They include Sukhoi Su-27s, MiG-29s and the Aero L-39s used for training. Modernization of the MiG-29 and Su-27 involves upgrading the radar to improve range and performance as well as weapons designation. The air arm also wants to improve the accuracy of unguided weapons used on the Su-27.
Ukraine also wants to improve the quality of training it can conduct on the L-39 in order to prepare crews for combat. Engine performance is also being improved on the trainer.
But while reliant on Soviet-era types, the Ukrainian defense ministry is looking to the West for its future combat aircraft, with the official naming the Eurofighter Typhoon,Dassault Rafale, Saab Gripen, F/A-18 Super Hornet and F-16.
The Ukrainian defense ministry hopes to begin a process to purchase a new fighter in the early 2020s.