Defense industry executives have largely attributed the supply-chain woes of recent years to the coronavirus pandemic. But more than a year after the widespread arrival of COVID vaccines, shortages of skilled workers are still delaying weapons deliveries and eating into firms’ profits.

“We really expected, as COVID receded into the background, that we would see a quick recovery in the supply chain and in fact that was wrong,” Raytheon Technologies CEO Greg Hayes told investment analysts Tuesday during the company’s quarterly earnings call. “The labor challenges that we continue to see have not abated and…I think that is the challenge and that’s the reason we continue to struggle in supply chain.”

Hayes told Defense One last week that more than 350 of the company’s 174,000 employees are working directly on managing supply-chain slowdowns.