A key Boeing 737 Max supplier said Friday that it is planning to cut about 2,800 jobs as the planes remain grounded far longer than expected and the financial impact ripples through the aerospace company's supply chain.

Wichita, Kansas-based Spirit Aerosystems, which produces fuselages for the beleaguered planes, said it made the decision due to uncertainty around the Max's return to service. The company's shares fell after its announcement, trading down 2.7%. Boeing was off nearly 1.5%.

The 737 Max accounts for half of Spirit's revenue. The planes have been grounded since mid-March after the second of two fatal crashes — one in Indonesia in 2018 and another in Ethiopia nearly five months later — killed all 346 people on board the flights. Regulators haven't said when they would allow the planes to fly again.