To all those claiming that MAYDAY MAYDAY MAYDAY would have been a more effective call, keep in mind that there are several examples of mayday calls in the US which were followed by the controlled asking "Are you declaring an emergency?"
RT in the US is a total
show, especially for emergencies. There's just no way around it and no way to fix it without retraining the entire country.
I attended a lecture by the crew of Southwest 1380 a couple years ago, they were given around 10 frequency changes after "declaring an emergency", were asked 3 times for fuel on board (twice in pounds and once in hours and minutes), and when they requested a single frequency were refused. 121.5 is not available for emergencies since it's reserved for cat noises and "GAUUUURD" calls. When someone in the audience suggested they might have been better off dropping the radio at that point and flying the plane, the F/O said that in his previous job he used to patrol that airspace with live weapons and didn't want to get shot down by one of his comrades.
If you're in trouble in FAA airspace, neither ICAO nor FAA standard phraseology is going to guarantee the RT goes well. Just do your best a la British Airways 9.