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NTSB Report
July 9, 1991 · Boeing 707-323C · N8404
Denver, CO
Overview
Report Status
Probable Cause
Event Type
Accident
Date
July 9, 1991
Injury Outcomes
No injuries (6 uninjured)
Location
Denver, CO
Aircraft
Boeing 707-323C
Tail Number
N8404
Operator
Southern Air Transport Sat
Injuries
None
Aircraft Damage
Substantial
NTSB Number
DEN91FA098
DURING ROTATION ON THE TAKEOFF ROLL, THE NOSE LANDING GEAR CAME OFF THE AIRPLANE AND REMAINED ON THE GROUND. AS THE AIRCRAFT PASSED OVER THE NOSE LANDING GEAR ASSEMBLY, DAMAGE OCCURRED TO THE BELLY OF THE AIRCRAFT. TAKEOFF WAS COMPLETED AND AN EMERGENCY LANDING WAS CONDUCTED WITH THE MAIN LANDING GEAR AND THE STUB OF THE NOSE LANDING GEAR SHOCK STRUT EXTENDED. DISASSEMBLY OF THE SHOCK STRUT INNER CYLINDER REVEALED THE ABSENCE OF SEVERAL PARTS. THE AREA WHERE THESE PARTS ARE LOCATED IS A SEALED AREA THAT WAS NOT COMPROMISED. THIS DISCREPANCY ALLOWED A RETENTION NUT TO BACK OFF WHICH RESULTED IN NOSE GEAR SEPARATION. THE NOSE GEAR ASSEMBLY WAS OVERHAULED ON 9/4/85.
NTSB Probable Cause
IMPROPER OVERHAUL OF THE NOSE GEAR ASSEMBLY BY OTHER MAINTENANCE PERSONNEL.
Full Narrative
DURING ROTATION ON THE TAKEOFF ROLL, THE NOSE LANDING GEAR CAME OFF THE AIRPLANE AND REMAINED ON THE GROUND. AS THE AIRCRAFT PASSED OVER THE NOSE LANDING GEAR ASSEMBLY, DAMAGE OCCURRED TO THE BELLY OF THE AIRCRAFT. TAKEOFF WAS COMPLETED AND AN EMERGENCY LANDING WAS CONDUCTED WITH THE MAIN LANDING GEAR AND THE STUB OF THE NOSE LANDING GEAR SHOCK STRUT EXTENDED. DISASSEMBLY OF THE SHOCK STRUT INNER CYLINDER REVEALED THE ABSENCE OF SEVERAL PARTS. THE AREA WHERE THESE PARTS ARE LOCATED IS A SEALED AREA THAT WAS NOT COMPROMISED. THIS DISCREPANCY ALLOWED A RETENTION NUT TO BACK OFF WHICH RESULTED IN NOSE GEAR SEPARATION. THE NOSE GEAR ASSEMBLY WAS OVERHAULED ON 9/4/85.
Flight
Event TypeAccident
Event Time20:36 MDT
Nearest AirportStapleton International (0nm N)
Runway17
Runway Length12000 ft
Runway Width200 ft
Flight Plan FiledIFR
Aircraft FireNo
Aircraft ExplosionNo
Aircraft
AircraftBoeing 707-323C
Tail NumberN8404
Aircraft CategoryAir
DamageSubstantial
OperatorSouthern Air Transport Sat
Operating RulePart 121
Engines4
Engine TypeTurbofan
Engine DetailsP&W · JT3D-3B · Turbofan · 18500
Seats7
People & Injuries
Injury SummaryNo injuries (6 uninjured)
Fatal0
Serious0
Minor0
Uninjured6
Total6
Crew 1Age 50 · First Class
Conditions
ConditionsVMC
LightDusk
Wind190° @ 5 kt
Visibility50 sm
CeilingBroken clouds 25000 ft
Temperature / Dew Point0 C / 0 C
Altimeter0
Weather SourceWIT