It's no secret that aircraft manufacturer Boeing has been on the hot seat ever since the crashes of two of its 737 MAX aircraft. That seat just got a little hotter yesterday when Boeing announced that fixes to its software would be delayed.

First, Lion Air Flight 610 -- a Boeing 737 MAX 8 aircraft -- crashed on October 29, 2018 shortly after takeoff from Soekarno-Hatta International Airport in Jakarta. All 189 passengers and crew died in the disaster.

Then, on March 10, 2019, Ethiopian Airlines Flight 302 -- another Boeing 737 MAX 8 aircraft -- crashed soon after takeoff from Addis Ababa Bole International Airport in Ethiopia. All 157 passengers and crew died in this latest disaster involving Boeing 737 MAX aircraft.

After initially resisting calls to ground the Boeing 737 MAX, on March 13, 2019 the FAA did just that. And, a day later, Boeing suspended deliveries of the aircraft while it focused on determining the cause of the crashes and coming up with a fix.

Unfortunately, that fix -- which was expected to be developed quickly -- was just delayed for at least several weeks, and perhaps even longer.

According to news reports, Boeing had planned to submit its fix to the FAA for review last week, but that schedule turned out to be too optimistic. According to an FAA statement,

The FAA expects to receive Boeing's final package of its software enhancement over the coming weeks for FAA approval. Time is needed for additional work by Boeing as the result of an ongoing review of the 737 MAX Flight Control System to ensure that Boeing has identified and appropriately addressed all pertinent issues.

Of course, there's no guarantee that the fix will actually arrive on its new schedule, or that it will work to the FAA's satisfaction. It may now be late spring or even summer before the fixes are fully tested and approved, and the FAA allows the troubled aircraft to fly once more.

In the meantime, the three U.S. airlines with grounded 737 MAX aircraft -- Southwest, American, and United -- continue to lose millions of dollars as they juggle their schedules to make up for the out-of-service aircraft. American Airlines has canceled dozens of flights a day since its 737 MAX aircraft were grounded by the FAA.

Says American Airlines spokesperson, Ross Feinstein, 

We are aware that the resumption of service for our 737 Max aircraft may be further delayed, and our team will work with all customers impacted by any flight cancellations.

It appears that there will be many more flight cancellations for Southwest, American, and United before this fiasco is resolved.