Originally Posted by
reelbigchair
Someone can obviously correct me if I'm wrong on this but I believe the common type only works one direction. I think you have to get the -200 first, and then you can get qualified -700/-900 through differences. I do not believe you can get -700/-900 and then do differences in the -200.
No, you can do your baseline qualification on any of the three, and then complete difference training for any of the others. Most airlines seem to use the 200 as the baseline, since that's what their training programs were originally set up for, and there are more buttons to push on the 200.
The CRJ type does not cover the Challenger, but challenger training would be a breeze for a 200 qualified pilot.