Russian authorities have extended until July the term for withdrawal from service of Antonov An-24, Tupolev Tu-134 and Yakovlev Yak-42 aircraft that have not been modernised.
After a series of incidents involving these types last year, the government intended to ban flights of An-24s, Tu-134s and Yak-42s unless they are equipped with collision avoidance systems, starting 1 January.
But several domestic operators, including UTAir-Express, Katekavia, Krasavia and Aerogeo, have appealed against the proposed requirement, citing high compliance costs and insufficient time to meet it.
"For instance, fitting the An-24 [with TCAS/GPWS equipment] would cost more than its residual value," said Anatoly Karavayev, chief of UTAir-Express, which has 20 An-24s and three Tu-134s.
"We're not ready to replace them yet. Grounding this fleet would be tantamount to ceasing regional and local services."
According to Karavayev, last December his peers raised the issue at an industry conference in Magadan to tackle availability of air transport services for residents of remote territories.
He said: "The conference was chaired by [Russian Prime Minister Vladimir] Putin. Taking account of our arguments, it made a decision to put off the implementation of new requirements for six months."
He added that UTAir-Express plans to phase out Tu-134s and retire a portion of An-24s, with the remainder to be upgraded as requested before July.