It may seem to be illogical that only AA the world's largest operator of MD80 series aircraft cancelled such a large number of flights operated by these aging aircraft.
The route cause is probably a clear miscommunication between the FAA and the airline's maintenance people. Sorry chaps this should not be the case. About half of the world's largest airline's fleet is MD82/83s. So you would think by now they would know what the wiring bundle looks like. If my memory serves me right this is about 1/3rd of the total MD80 fleet.
I checked the other operators in the USA - Delta is the next biggest with over 100 and a smattering of the MD90s also but it has the much newer MD88s as its mainstay. No flight cancellations today. None from either Allegiant or Alaska.
Nor in Europe or anywhere else. The next largest operator I think is Alitalia. They also did not report major problems.
American has always marched to its own tune with regard to maintenance. Some of us remember the unorthodox way they removed CF6s of DC10s with a fork lift truck. Fine until one of the engine bolts sheered as a result and the results were disastrous.
The knee jerk response by the FAA to cover its own short comings with these emergency inspections may have an adverse affect. The hard pressed line engineers at AA have had to endure consecutive weeks of long overtime periods while they inspect the planes and get them back in the air.
I hope the FAA has enough inspectors in place to make sure these inspections occur properly. Not good chaps...