What happened
On September 6, 1985, Midwest Express Airlines flight 1ob5, operating a DC-9 registered as N100ME, was preparing for departure from Milwaukee International Airport. After arriving from Madison and completing necessary ground procedures, the crew received IFR clearance for their flight to Atlanta. During the takeoff roll on runway 19R, the flightcrew was following standard noise abatement and reduced thrust takeoff protocols.
The aircraft achieved liftoff approximately 4,200 feet from the start of the roll and climbed steadily. However, at an altitude of roughly 450 feet, a loud noise occurred accompanied by a significant change in engine sound. The air traffic controller observed smoke and flames emitting from the right-side engine. While the crew declared an emergency, they failed to execute specific engine failure procedures, such as applying maximum power or checking the fuel system.
As the aircraft continued its climb, it began to veer sharply to the right, with the heading shifting from 194 degrees to 260 degrees in just eight seconds. The vertical acceleration fluctuated significantly before the aircraft entered an accelerated stall at approximately 156 knots.
Findings
- The primary cause of the accident was the flight crew's improper use of flight controls following the catastrophic failure of the right engine during a critical phase of flight.
- A lack of effective coordination between the pilots during the emergency contributed to the loss of control.
- The mechanical failure originated from a rupture in the high pressure compressor, specifically involving the 9th to 10th stage removable sleeve spacer, which was susceptible to cracking.