What happened
During the descent phase of Delta Flight 723, the aircraft was unable to maintain a stable approach profile. Due to air traffic control delays caused by the management of other potential conflicts in the area, the crew arrived at the outer marker with an excessive airspeed of 385 km/h and an altitude 60 meters above the glide slope.
During this period, the flight director was accidentally set to a go-around mode, which generated irregular instrument readings. This technical discrepancy caused significant distraction for the first officer, who was responsible for flying the approach. As the crew focused on resolving the flight director issues, the DC-9 continued its descent below the required path. The aircraft eventually struck a seawall approximately 3000 feet short of runway 04R and 150 feet to the right of the centerline. The impact caused the plane to crash and ignite.
Regarding the casualties, there were two survivors of the accident; however, one passenger died the following day, and the second passenger passed away on December 11, 1973.
Findings
Investigations concluded that the primary reason for the accident was the crew's failure to monitor their altitude and recognize that they had descended below the approach decision height. The approach was deemed unstabilized due to the high speed and vertical deviation at the outer marker. This instability was further exacerbated by the crew's preoccupation with erroneous flight director indications. Additionally, nonstandard air traffic control procedures contributed to the aircraft's poor positioning for the final approach.