Southwest is cancelling fewer flights today than on Saturday and Sunday -- 77 as of mid-morning, compared with about 600 total over the weekend.
On Saturday, the airline grounded 79 of its Boeing 737-300s for inspections for structural cracks after a five-foot hole ripped open Friday on a 737-300 with 118 passengers and 5 crew aboard at 35,000 feet over western Arizona. The plane made an emergency landing in Yuma.
Meanwhile, another Southwest flight had a problem last night and was diverted to Los Angeles with 142 aboard when an electrical burning smell permeated the cabin. That flight was bound from Oakland to San Diego.
Initial reports don't say whether that plane was a 737-300 model, but with 142 aboard it most likely is, as later model 737s have slightly smaller capacities.
The 737-300s are no longer in production by Boeing, but are still widely used by world airlines. Some of them also have been converted to private jets and some are in use as freighters.
Paul Sheridan, the head of risk for Ascend, the aerospace investor advisory firm, pulled together a list of all of the 737-300s currently flying.
Here's the breakdown:
Operators with more than 10 aircraft. Figures are aircraft currently In Service and include freighters and other uses:
China Southern Airlines--25
China Eastern Airlines--16
Air New Zealand--15