B737-800
Flight Crew Air Transport Pilot (ATP)
Deviation - Speed All Types; Deviation / Discrepancy - Procedural FAR; Deviation / Discrepancy - Procedural Published Material / Policy; Inflight Event / Encounter CFTT / CFIT
Flight Crew Became Reoriented; Flight Crew FLC complied w / Automation / Advisory; Flight Crew Took Evasive Action
Environment - Non Weather Related; Airport; Human Factors
After flying the OJAAY arrival into DCA; [we were given] radar vectors to the north of DCA for the River Visual 19; light winds and clear skies. We reported the Potomac River in sight when asked by ATC. I was Pilot Flying and had acquired a visual on the Potomac so that we could fly the ground track to the airport. I continued to gradually descend in vertical speed mode while configuring the aircraft and precisely flying the river; being careful not to overfly the prohibited areas. I leveled off at approximately 550 feet AGL while; visually; [we appeared to be] three to four NM from the airport. FOQA reported that we were five to six NM from airport [where] the RIVER VISUAL procedure recommends 1;800 feet. I easily had visual contact with all the structures on the banks of the river. GPWS alerted us with one 'too low; terrain' advisory. I initiated a gentle climb back up to 8 or 900 feet AGL and started to acquire the VASIs at the runway and completed an uneventful landing. Additionally; on the descent below 10;000 feet; the airspeed did not decelerate below 250 until we were approximately 8;500 feet. More attention to altitude on the visual approach and airspeed on the descent is required on my part in the future. A combination of factors played a part in this event; fatigue being one of them. We started late and ended late; flying two long legs; [the first requiring] passage through Immigration and Customs; changing planes and flying into a challenging domestic airport (DCA) late at night. I had not flown into DCA in years. My First Officer was a recently recalled from furlough pilot with limited experience on the plane. I; personally; have only three months experience on the plane as well. The combined lack of experience on the plane and the challenging arrival airport; compounded with fatigue makes a fertile ground for errors. I will prepare even more so the next time these circumstances present themselves.
The reporter advised the RIVER VISUAL approach is not a line selectable procedure.  As a back-up he had line selected the RNAV (RNP) Rwy 19 approach for situational awareness.  Doing so provided computed vertical glide path guidance via the VPI (Vertical Path Indicator); but he forthrightly declared that he had failed to monitor the display as he concentrated on maintaining the lateral track over the river; conscientiously avoiding the two prominent prohibited areas.  At the time he believed he had good visual awareness of the descent relative to the airport; an awareness he now declared was obviously inaccurate.He advised neither pilot was sufficiently experienced with the approach to be able to recognize or relate to the multiple bridges along the Potomac as visual indicators of appropriate altitudes as they were passed.He stated that; in the future; his preferred technique would be to utilize the RNAV procedure for lateral awareness and hard tune the DCA VOR as a reference for the recommended altitudes at given DMEs as depicted on the RIVER VISUAL.
Was just alerted to the fact that we got REALLY low on the River Vis 19 at DCA. It was VFR conditions; midnight with an overcast layer and it was really dark. As the Pilot Not Flying; I lost SA! I thought we were further [down] the river than we were.  When we received a Terrain Alert I thought were at the George Mason Bridge and received the alert because we were LATERALLY to close to it (to the right; inside of the turn). When in actuality (as I learned today) [we were] at the 3 DME turn at the Key bridge. Because I thought we were turning final. I flipped up the cover and turned the Terrain warning off and announced it to the Captain. Looking back; I'm not convinced he heard me. Also; I just remembered; I had the wrong crew show time for the departure in CUN; so I showed up in the lobby two hours early. Tried to go back to my room; but they were already cleaning it; so I sat and read in the lobby until the rest of the crew showed up. Completely my fault! BACK UP THE DME OFF THE VOR. Go old school and be safe. Really think something was not set up correctly with the VNAV.
A B737NG flight crew descended to 550 feet AGL six miles from the airport; versus recommended 1;800 feet MSL; while conducting a RIVER VISUAL approach to Runway 19 at DCA.  Following receipt of an EGPWS Terrain warning they climbed and re-established the profile to a safe landing.