Unusal US Govt. 747 in Kabul Today

Today’s Bloomberg News includes a photo of new Secretary of Defense Aston Carter arriving in Kabul. His aircraft in the background is a 747 with the USA livery. However, there is something atop the fuselage that I’ve never seen before. It looks a little like a radar pod or a portion of a jet engine intake (strange place for that). Does anyone know what this is? Also, is this aircraft part of the presidential fleet or is it regularly used by the Defense Dept.?

Without seeing the actual picture I’d have to assume it’s one of the U.S. Airforce E-4s. I believe the hump houses satellite communications equipment.

I think this is the photo that the OP is referring to.

wsj.com/articles/defense-sec … 1424485205

The aircraft is an E-4B.

Marty

I believe this would be it. http://media.gotraffic.net/images/iasvopMKvx4o/v12/1200x-1.jpg

http://en.wikipedia.org/wiki/Boeing_E-4