Since Cathay Pacific is a foreign company, they are not subject to USERRA (Uniformed Services Employment and Reemployment Rights Act). Therefore, they do not have to give you off for drills or deployments.
Little by little, they are switching to onshore companies (UK switched in April). If they switch to an onshore company (US Company), then I imagine it would be like any other US company where they have to give you off for drills.