Accident McDonnell Douglas DC-8-63F N950R,

Date:	Thursday 13 July 1989
Time:	01:13
Type:	McDonnell Douglas DC-8-63F
Owner/operator:	Emery Worldwide
Registration:	N950R
MSN:	45903/286
Year of manufacture:	1967
Total airframe hrs:	53209 hours
Engine model:	P&W JT3D-7
Fatalities:	Fatalities: 0 / Occupants: 3
Aircraft damage:	Substantial, repaired
Category:	Accident
Location:	Dayton-James Cox Dayton International Airport, OH (DAY) - United States of America
Phase:	Taxi
Nature:	Cargo
Departure airport:	Charlotte-Douglas Airport, NC (CLT/KCLT)
Destination airport:	Dayton-James Cox Dayton International Airport, OH (DAY/KDAY)
Investigating agency:	NTSB
Confidence Rating:	Accident investigation report completed and information captured

Narrative:
As the DC-8 crew began the after landing check, a decrease in quantity of hydraulic pressure was noted. The captain elected to leave the flaps extended, though the spoilers were retracted. Hydraulic pressure remained normal and the crew continued to the ramp. While taxiing, the quantity suddenly went to zero; the nosewheel steering and normal brakes became inoperative. Attempts to stop by using emergency pneumatic braking were unsuccessful. The captain tried to reverse thrust from no. 2 and no. 3 engines, but they would not reverse (no. 1 and 4 engines were shut down). The aircraft was on a slope; it subsequently rolled into a Boeing 727. An examination revealed the bogie trim cylinder on the left main landing gear had ruptured. The air bottle for pneumatic braking was charged to operating pressure, but movement of the airbrake lever would not operate the control valve; though no anomalies were found in rigging/alignment.

PROBABLE CAUSE: "Failure of the left main landing gear, bogie trim cylinder, and malfunction of the emergency airbrake control valve."

Accident investigation: