It has now been disclosed that Romania had to ground its MiG-21 fleet because the jets were supplied with low-quality jet fuel.
Airwolfhound from Hertfordshire, UK, CC BY-SA 2.0, via Wikimedia Commons
According to Gandul, local businessman Cristian Berendel was given a contract to supply fuel from 2018 to 2022. While the initial batches of fuel were of acceptable quality, Berendel quietly began supplying low-quality fuel from Greece and Turkey.
Overtime, the fuel pumps of the jets began exhibiting symptoms and were unable to operate properly.
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