Yes, Cheyenne is roughly halfway, 1740 miles form New York and 1175 miles from San Francisco. Another possibility, depending on who's taking the first shift, is Kansas City at 1200 miles from New York and 1800 from San Francisco. Personally, I'd add a seventh day to this journey. The other thing to keep in mind is the cost of plane tickets. The cost of two one-way tickets using Cheyenne as your changeover point will be around $440, while using Kansas City reduces that cost to $265. It would be nice if there were a major hub airport with lots of competing airlines exactly halfway along your route, but alas, there isn't. Perhaps a better compromise might be Omaha, NE. It's on your route, 1240 miles from New York and 1670 from San Francisco, and the plane tickets could be had for $315.

AZBuck