I have a technical question:

On Tuesday I flew WN961 OAK-HOU on a 737-500 (ugh ) and we only flew at 29,000 ft. Looking at FlightAware, that aircraft never went above 30,000 ft on any of the segments it flew that day with, against, and across the jet stream. I know the -300s abd -500s don't have the ceilings that the -700s have but they can usually get up to FL330 or FL350, especially on longer segments.

http://flightaware.com/live/flight/S...015Z/KOAK/KHOU

I remember seeing a thread either here or over at airliners.net that mentioned something on the MEL that allowed the plane to fly but limited to below 30,000 ft. I recall that it is something like if only 1 of the 2 (_____) is working correctly then the plane has to stay below 30,000 ft.