A domestic air carrier flight has a delay while on the ground, at an intermediate airport. How long before a redispatch release is required?

Explanation

Under 14 CFR 121.631, a domestic flight that remains on the ground at an intermediate airport for more than 1 hour must be redispatched before it continues, so the delay without redispatch may not exceed 1 hour. The 6-hour figure applies to flag operations.