NONE · BOEING 757-236 · 2023-10-05 · Chattanooga, TN, USA
Event
NTSB number
DCA24FA002
Event ID
20231005193196
Type
Accident
Date
2023-10-05
Location
Chattanooga, TN, USA
Coordinates
35.035272, -85.203889
Injuries
Highest injury
NONE
Fatal
0
Serious
0
Minor
0
Uninjured
3
Total aboard
3
Aircraft
Make
BOEING
Model
757-236
Registration
N977FD
FAR Part
121
Engines
2
Damage
SUBS
Conditions
Light
NITE
Weather
VMC
Probable cause
The failure of the alternate gear extension system, which prevented the landing gear from being lowered. The cause of the system failure was a broken wire, due to tensile overload, between the alternate gear extend switch and the alternate extension power pack (AEPP), preventing the AEPP from energizing and supplying hydraulic fluid to the door lock release actuators for the nose landing gear and main landing gear. Contributing to the accident was the loss of the left hydraulic system due to a ruptured left main gear door actuator hose from fatigue, which prevented normal landing gear operation.