I did an operation rain check last January at Potomac Tracon. They asked
for Pilot certificate number. Over 120 attended.
Michelle

wrote:

I was wondering if has anyone visited ATC facilities recently and had
to prove US citizenship. I have heard some people that visited Potomac
Approach were not asked for this, but Seattle Approach keeps blocking
non-citizens including permanent residents.

Thanks..

Baha Acuner
www.AcuWings.com