IAD: Going from Terminal D to B - all airside?
 

If I go from Terminal D to Terminal A and back to Terminal C, can I stay all post-security (i.e., I can avoid having to go through security again)?

I see I can take transportation btwn the terminals. What's the difference/advantages/cons btwn the Aerotrain and the shuttle (besides what terminal it leaves/arrives at)?

I'll likely be landing at Terminal D but want to go to Terminal A during my 2hr 20m layover. Next flight leaves from Terminal C to Canada. Thinking this was very doable but may reconsider if I have to go through security again because of the extra delay it will cause. I have Nexus/Global Entry if that makes a difference.

Any insights much appreciated!

cheers,
:)

Yes you can do all of that post-security. IAD has a single centralized security checkpoint, and both the aerotrain and shuttle are post-security. Aerotrain is a small people-mover train system that runs underneath the airport, you'll have to go down escalators to get to the platform area. The walk between C and D and the walk between A and B is doable, and the train is likely a quicker option, though there's some extra walking to get up and down to and from the platform.

If I recall correctly, the shuttle is in one of the old-fashioned mobile lounges and goes along the tarmac which I think is a fun experience if you haven't tried it before and if it's running! These leave from the gate area, so you won't have to go down several levels of escalators in order to board.

(Last time I was at IAD was early 2016 so my train information is up to date; haven't been in Terminal D in about 4 years, so not sure how up to date my shuttle info is).

ryw, thx a mint for the info and reply...much appreciated! Great info and looks like I'll be able to do it stress-free. Best of the season to you!

cheers,
:)

Same to you klamchowder, and happy travels! :)

The shuttle between A and D is not always running. I am not sure of the exact hours, but I know there is an early evening period when it is not running, since that is usually when I want to use it.

Note that the train does not actually run to Terminal D. You can either use the shuttle between the D gates to the main terminal to connect to the train to A or walk to the C gates. The walk between the C gates and the train is nearly as long as the walk from C to D.

A-D shuttle schedule graphic. Note that even when it is running, it may be 8 minutes or so between shuttles at quieter times.