How do you get back into teaching after being overseas for 10 years and lacking good computer skills?
Some community colleges have pre-engineering programs in which someone with a Ph.D. in engineering could be an instructor.  The engineering courses offered in these programs are typically very limited.  Courses like thermodynamics are not typically offered at the community college level.

Most community colleges have rules for the required academic background of instructors.  For example, a fairly common rule is that instructors are required to have 15 credit hours of graduate-level coursework in the subject that they are teaching.  These kinds of rules might well prevent your friend from getting a job teaching mathematics, chemistry, etc.  

Your friend might also consider applying for a job as a full-time instructor at a four-year college that has an engineering program.