Interesting and thanks for the replies. My Grandfather ran the TWA training department in the early to mid 60's but then went back to the line (after a side trip on loan to Saudi Arabian airlines). He told me that TWA used to give upgrade rides to co-pilots at five years and it was an up or out type of deal - that didn't mean you could necessarily hold a Captain line, but they wanted to know you could do the job. May have some details of this confused as this was long ago that we talked about this. He also always told me that TWA was a "pilots airline"...which I assume meant that pilots had perhaps more input than at other lines.