Can I drop someone off at Phoenix Sky Harbor in my MH

I use Sky Harbor all the time. I don't believe there are any low clearances on the main road through the airport that would preclude you from driving through. Remember that large sized buses drop off and pick up passengers there all day long. You might have a problem getting to the curb to drop them off, but as long as they don't mind walking a little bit, I think you would be okay. If you can't find a place to pull over, you could take gcloss's advice above.