SEATTLE, WASHINGTONCzech airline operator Smartwings filed suit against American aircraft manufacturer Boeing to compensate its losses damage to the grounding of 737 MAX jets more than a year after two fatal crashes.

Smartwings ordered eight 737 MAX jets directly from Boeing and opted to lease an additional 31 aircraft of the same type. The airline took the delivery of its first MAX in January 2018, and six more leased planes followed it before the type was grounded all over the world after the second crash in March 2019.

The complaint alleges that in implementing a software addition to the MAX’s flight controls, “Boeing chose a cheap and hastily implemented bandaid” rather than more expensive aerodynamic changes to the airframe.

Smartwings also claims Boeing failed to conduct a full safety evaluation of the failure modes of the software, known as the Maneuvering Characteristics Augmentation System, and then “misled the Federal Aviation Administration and other regulators regarding the nature and purpose of MCAS.”