Washington ? The aviation industry is trying to water down a key safety change recently passed by Congress in response to a regional airline crash last year that killed 50 people.

A Federal Aviation Administration advisory panel dominated by airlines, companies that employ pilots to fly corporate planes and university flight schools wants to reduce by two-thirds a requirement that airline co-pilots have a minimum of 1,500 hours of flying experience — the same experience threshold that captains must meet.

The key issue is money, according to officials familiar with the panel’s deliberations. Airlines worry that if the FAA raises the threshold for co-pilots — also called first officers — from the current minimum of 250 hours, airlines will be forced to raise pilot salaries and benefits in order to attract more experienced fliers, said the officials, who spoke on condition of anonymity because they weren’t authorized to speak publicly.