B737-800
Flight Crew Multiengine; Flight Crew Air Transport Pilot (ATP); Flight Crew Instrument
Flight Crew Last 90 Days 0; Flight Crew Total 5500
Inflight Event / Encounter Wake Vortex Encounter
Flight Crew Regained Aircraft Control
Environment - Non Weather Related; Procedure
On departure from DCA as gear came up the aircraft right wing dipped 25 deg due to wake turbulence.  The wake turbulence was confirmed by the pilots. The severity of the wing dip is the reason I am submitting as a passenger as this was a close call to a major mishap. With wing deflection as great as occurred at low altitude the only thing that prevented a mishap was the rapid correction displayed by the pilots. I am unaware of ATC takeoff clearance and any cautions. I am unaware of the type aircraft departing prior to our departure and the time interval. I am.also unaware of the winds and direction. I only observed the result of the wake turbulence and felt compelled to report it.
Air carrier passenger reported noticing a wake turbulence encounter departing DCA airport.