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Case Study: Air Florida 90

"Larry-we're going down Larry!".

First Officer-Roger Pettit

Gregory C. StampASCI 604 Human Factors (Prof. Dr. R. Tyler)

Embry-Riddle Aeronautical University

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AGENDA

Background Accident Details “How and Why” Human Factors Application Conclusion

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Background

Date: January 13, 1982 Bitter winter’s day with blizzard of snow Temperature Conditions: as low as -5ºC (? ºF) Limited Visibility: ½ mile in snow showers Cloud Ceiling: 400ft Flight Schedule: 2:15 pm Boeing 737 departure (National Airport to Fort Lauderdale, FL)

Aircraft flight hours: ? Maintenance history: ?

Passengers: 74 Cock Pit Personnel:

Pilot: Captain Larry Wheaton First Officer: Roger Pettit Both were fairly young pilots/ new at Air Florida

Airline: Air Florida had rapid growth after Deregulation Act of 1978

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Accident Details

Key Events Leading up to Crash (Timeline): Just Before 1:40pm

Closed airport to plough instrument runway Captain requested de-icing and then cancelled

after rejection of departure 2nd de-icing requested after re-opening of airport

At 3:23pm Palm 90 cleared to depart gate Captain mis-used reverse thruster to assist in push

off (violation of company policy) Palm 90 taxied into position behind New York

Air DC-9 to melt snow

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Accident Details

At 3:59pm Palm 90 was cleared for take-off from

Runway36- visibility down to ¼ mile Within less than a minute after take-off- Palm

90 loss airspeed and started descending and ploughed in 14th Street (“Rochambeau”) Bridge

Fell into Potomac River with only the tail visible

After Crash- “The Aftermath”: Rescue team impeded by icy conditions Only 6 people survived, 4 motorists died Recovered both the FDR and CVR from the

bottom of the river Critical in solving the puzzle of Palm 90”.

Discovered captain stated anti-ice switch was offwww.roadstothefuture

.com/Air_Florida_Map_M.jpg

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“How and Why”

‘How:’ Captain Wheaton positioned Palm 90

behind New York Air DC-9, use exhaust to melt the ice off fuselage and wings

Counter effect ice melted and blew back over the wings and re-frozen

Anomalies in engine instrument readings Investigation concluded:

Failure to use engine anti-ice mechanism Created large amounts of ice and snow to gather in the engines without being

melted.

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“How and Why”

‘Why:’ Exhaust from the DC-9 caused a lower than normal reading on one of the EPR gauges. Spectrum analysis of the engine sounds from the CVR indicated that the anomalies in engines out the takeoff. Investigators found that the engine de-ice system was turned

off Ice on the compressor inlet pressure probe would cause a

higher than actual thrust reading on the EPR gauges. Investigators found that ice build up in the wing leading edge and slats could cause an abrupt nose up pitch

on takeoff First Officer Pettit believed that the engines were producing

max thrust The throttles weren’t advanced to provide more power to

prevent stall

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Human Factors Application

Decision Making: Poor decision chain attributed Palm-90 accident Determine what must be done Pilot judgment error Inappropriate procedures

Crew Resource Management: Accident help initiated training in crew resource management Instill professional pilots a positive attitude and skills Improve flight crew communication.

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Human Factors Application

Communications Break down in flight crew communication First Officer Not assertive with communication to

Pilot Ex: “Pettit remarked several times that "that

doesn't seem right!" Training

Air Florida lacked the necessary infrastructure Provide adequate training for flight crew Improper supervision of flight operations. Lack of experience from both Pilot and Co-pilot

Selection

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Questions???