Military Capabilities

Bulgarian Air Force returns second Mi-24 attack helicopter to service

02 January 2018
Aircraft 142, previously the Bulgarian Air Force's sole serviceable Mi-24V, has been joined by another, freshly overhauled ‘Hind’, but it remains uncertain if others may follow. Source: Bulgarian Air Force/Capt D Vichev

Key Points

  • The Bulgarian Air Force has returned a second Mi-24 ‘Hind’ attack helicopter to service
  • It is uncertain whether the refurbishment of four other ‘Hinds’ will go ahead

The availability of Bulgarian Air Force (Voennovozdushni Sili, VVS) Mi-24 ‘Hind’ attack helicopters was doubled from one to two aircraft on 21 December when a newly overhauled, 1986-produced Mi-24V ‘Hind-E’ (No 143) rejoined the VVS’s 24th Helicopter Air Base at Krumovo following heavy maintenance at the Sofia-based TEREM-LETETS aircraft repair plant.

With its time between overhauls (TBO) reset to 1,000 flight hours or seven years (whichever occurs sooner), the aircraft also had its original 25-year life cycle extended to 35 years, allowing operations until January 2021. At this point the aircraft will be grounded and a new inspection required to determine whether it is fit for another life-cycle extension that would allow use of its entire calendar TBO resource, which grants operational use until December 2024 under the assumption that the allocated number of flight hours will not be spent before that date.

Also facing the pressure from an expiring life cycle is the other serviceable Bulgarian Mi-24V (No 142), which, following heavy maintenance at TEREM-LETETS, re-entered service on 30 November 2015. This aircraft’s seven-year calendar resource expires in November 2022, but it is now scheduled to be grounded almost two years earlier, in February 2021, when its extended 35-year lifecycle is set to expire.

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