while other sources report this order to be for ten aircraft. On 28 April 2013, Ukraine's Antonov aircraft maker handed over a third An-158 passenger airliner to Cuba and signed a contract for the delivery of three more. In April 2016, Indian company Reliance defense limited and Antonov entered into an agreement to construct an aircraft based on An 148/ An 158 for defense and commercial purposes. In April 2017, Cubana de Aviación suspended its flights between Havana and Guantánamo due to "technical problems" with its An-158 fleet. The route from Havana to Holguín also had problems: of 116 planned flights in the first months of 2017, 38 were cancelled and 36 suffered significant delays. Yoanka Acosta, head of Cubana's commercial division, explained that the planes were leased from Ukraine but spare parts were sourced from Russia, so the state of conflict between the two countries had affected the supply of parts, making maintenance difficult. In late April, however, representatives from Antonov and Cubana met and signed a service agreement that extended the aircraft's navigation directives to 3,600 flights and guaranteed the supply of spare parts, although it did not specify a date for normalization. In March 2018 Rostransnadzor suspended all flights of An-148 in Russia after crash on 11 February 2018. In May 2018, Cubana de Aviación grounded its An-158 fleet after it received an order from the Cuban National Aviation Authority. The official reason given by the Cuban National Aviation Authority was "multiple and repeating failures have been found in complex systems, built by mechanical, hydraulic and electrical components, as well as computer performance algorithms", in addition to "evidence of design and manufacturing flaws, serious issues in flight control system, cracks in the structure and engine temperature increase above normal parameters". Specifications Orders and deliveries The following sheet depicts all known orders and deliveries of An-148 aircraft. However it is unclear if all of them are currently operational: Incidents and accidents On 5 March 2011, an Antonov An-148 (assembled by VASO) carrying test registration 61708 crashed during a test flight in Russia's Belgorod Oblast after an inflight breakup, killing all six crew members on board. An investigation commission found that the crew permitted the aircraft to accelerate more than 60 knots above its "Never Exceed" speed in an emergency descent, which led to the inflight breakup. Witnesses on the ground reported a wing had separated from the aircraft