They probably still use ADA for system-crital cruft, but also C/C++/Java. However, since I haven't done any programming for the USN since about 1992, I can't say for sure!
As a side-bar, the Oracle PL/SQL language was derived from ADA. From the Department of Obscure Tech-Geek Knowledge Department... :-)
Also, ADA was the first (an may still be only) US government approved open source programming language for military operational systems - not to say there were never ANY allowed exceptions to that. They made it open source because they wanted to be sure that all variants could be properly audited and verified as correct to the language definition. Oracle used it for PL/SQL because it was open and freely available without attribution (or payment). Our tax dollar$ at work! :-)
#define A 3// name a constant
long int booking_ID ; ...