Just one in every five flights was late in August the government says, an improvement from earlier in the summer.
The Department of Transportation reported Wednesday that 78.8 percent of flights arrived on time in August. That was significantly better than the on-time arrival rates of 73.1 percent in July and 71.9 percent in June.
Among the biggest U.S. airlines, Delta's on-time performance improved to 85 percent from 74.6 percent in July. That was good enough for third overall behind Hawaiian Airlines and Alaska Airlines.
American Airlines ranked fifth, with 81.3 percent of its flights arriving on time. That's a strong showing for American. In the April-June quarter of this year the airline ranked 14th out of 16 major airlines, with an on-time rate of just 72.8 percent.