I can't find information on these new rules, but given that a commercial pilot course under part 141 will be around 120 or more hours, you'll easily complete the 18-22 hours per week of study required of M-1 visa students.
The problem, last time I contacted immigration about this issue, was communication between TSA and ICE. If you applied to TSA, they would ask ICE if you were in the country legally for the course of training. If you had no VISA, ICE would, of course, say no, and TSA may deny you. Between the two agencies, there was no desire to understand the position that some people are in when they desire to, quite legally, seek flight training which is incidental to their visit to the US.
Since TSA is not required for a Commercial certificate, they won't be able to create a problem, and so no visa is required.
As always I stand to be corrected if the rules have been changed recently.
Last edited by nh2301; 20th Aug 2008 at 07:56.