https://avherald.com/h?article=525d3638&opt=0DAL2983 was cleared for takeoff from Rwy 19 southbound at 19:15Z while flight of 4 T-38 Talons (c/s DRAGO61) were inbound @ 300kt in opposite direction for Arlington National Cemetery flyover after leaving a brief hold SE of Andrews at 19:13Z.
Tower tried contacting DAL2983 after takeoff but had already switched frequency. On Departure frequency, DAL2983 received normal instructions to 12k and waypoint clearance there was no corrective instruction (contrary to FAA statement) or apparent deviation in response to the RA. About 2 mins after switching to Departure, DAL2983 reported they'd had a 'momentary' TCAS RA for aircraft 500ft below, which controller confirmed was an aircraft.
Simultaneous to the DAL2983 clearance, DCA Final issued delay vectors for aircraft on approach to DCA. There was a comment on DCA Final that the flyby had "increased their time-over-target" which was the reason for delay.
Normally these flyovers are very tightly coordinated thru the DCA airspace but presumably something was missed with Tower on the timing change.
DRAGO61 departed Langley Air Force Base in Hampton VA at 18:47Z and entered a brief hold @ 2800ft SE of Andrews at 19:09Z before pushing inbound to ANC at 19:13Z @ 300kt. This was the second flyover of the day, earlier in the 1300Z hour a Poseidon P8 from Jacksonville FL had conducted a flyover after a longer hold (~35 mins) in similar pattern SE of Andrews.
The DRAGO flyover aircraft usually remain on a different Potomac frequency throughout they do not go through Tower; not able to find them on DEP/FINAL or KRANT frequencies, if not on those I am guessing they were on SFRA South (125.125) or ENSUE (124.2) but those frequencies are not available on LiveATC. Time over target and clearance to push are usually confirmed by/with the Potomac controller.
Attached is combination of Tower, Departure, OJAAY (DCA Final) frequencies, edited for time and content.