Thanks for all these posts concerning this...
I have been researching what is required for my own needs, and this info was very helpfull...
Yesterday I went to the PennDOT drivers license location in Rockview (centre county) to get my Class B permit.
The lady there was very helpful, and specifically asked if my motorhome had air brakes. She informed me that if the motorhome I brought to the skills/driver test had air brakes, I would be required to perform the "Air Brake Test" outlined in Section 5 of the commercial drivers manual for PA...
A check for $5 later and I was out the door... Now to do some more shopping before tax season brings my down payment...