Ed. Note: Possibly related to the 11:15am Navy Flyover at Arlington National Cemetery? Thanks to Renee for sending a photo of it:
J. reports around 11am: “In case people were wondering what the bangs at Navy Yard were. It was the navy seemingly firing a cannon this morning. Fortunately they waited to do it until I passed by in my kayak heading to Navy Yard.”
To the video:
