The Army is trying to thin out the ranks of its civilian helicopter instructor pilots with a 250-pound weight limit.
New military rules set to take effect Monday at the Army's aviation training center in Alabama limit their weight.
The Army is defending the limit, saying heavier pilots increase costs because more fuel is required to keep them aloft.
A union representing civilian pilots at Fort Rucker has filed a federal lawsuit trying to block the new weight restriction, but a judge hasn't ruled.
The suit includes six flight trainers whose weight ranges from 252 to 272 pounds, including flight suits.
The civilian trainers who sued work for URS Federal Support Services Inc., a contractor.