ATL04IA098

NTSB incident investigation · Cessna 208B · Tunica, MS · April 27, 2004

Incident · No injuriesIncident investigationFinal report
Date
April 27, 2004, 03:00 local (08:00 UTC)
Place
Tunica, MS
Injuries
2 uninjured
Damage
Minor damage
Phase of flight
Other
Aircraft
N738FXCessna 208B
Weather
Visual (VMC)
Status
Completed · report July 7, 2005
Report
Approved by Office Director
Parties
Jackson FSDO
Case key
59141

From the NTSB’s public API. By law, NTSB reports can’t be used as evidence in lawsuits over the incident.

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Probable cause

The pilot's improper use of the emergency power lever which resulted in excessive operating temperatures. A factor was the improper adjustment of the emergency power lever dead band.

Sequence of events

NTSB’s coding before 2008: each occurrence and phase of flight, and the causes and factors under it. The codes are defined in NTSB’s coding manual.

Airframe/component/system failure/malfunctionOther
Emergency procedure - simulated
Emergency procedure - inadequateCause
Powerplant controls - improper use ofCause
Fuel system,fuel control - out of calibrationFactor
Loss of engine powerOther
Forced landingDescent - emergency
On ground/water encounter with terrain/waterEmergency landing
Terrain condition - roadway/highway

Analysis

According to the check airman, during a demonstration procedure for loss of engine power, the check airman reduced the power lever to idle, turn on the ignition, un-stowed and advanced the emergency power lever (EPL). The check airman felt a vibration and heard a noise. He re-stowed the EPL and advanced the engine power lever. Flames exited the exhaust and the check airman shut down the engine, and made an emergency landing on a nearby road. After landing the airplane the two pilots attempted to remove the airplane from the roadway, and a passing truck struck the left wing of the airplane. Examination of the fuel flow control unit revealed that the EPL lever dead band was 7 degrees below the minimum requirement of 25 to 35 degrees. The fuel flow control unit began fuel flow at 18 degrees of lever travel. The manual override was disassembled and it was found that the plunger, which compresses the bellows, was allowed to contact the bellows prior to the required degrees of travel. Review of the pilot's operating handbook emergency procedures states: When using the emergency power lever, monitor gas generator RPM when reducing power near idle, to keep it from decreasing below 65% in flight. The emergency power lever may have a dead band, such that no engine response is observed during the initial forward travel from idle position.

Factual narrative

On April 27, 2004, at 0300 central daylight time, a Cessna 208B, N738FX, registered to and operated by Federal Express Corporation, made an emergency landing on a road during a training flight near Tunica, Mississippi. The non-scheduled flight was operated under the provisions of Title 14 CFR Part 135 with an instrument flight plan filed. Visual meteorological conditions prevailed at the time of the incident. The airline transport rated check airman, and airline transport rated pilot were uninjured, and the airplane was not damaged. The flight departed Memphis International Airport, Memphis, Tennessee, on April 27, 2004 at 0238.

According to the check airman, during a demonstration procedure for loss of engine power, the check airman reduced the power lever to idle, turned on the ignition, and un-stowed and advanced the emergency power lever (EPL). The check airman felt a vibration and then heard a noise. He re-stowed the EPL and advanced the engine power lever. Flames exited the exhaust and the check airman shut down the engine, and made an emergency landing on a nearby road. After landing the airplane the two pilots attempted to remove the airplane from the roadway, and a passing truck struck the left wing of the airplane.

Examination of the fuel flow control unit revealed that the EPL lever dead band was 7 degrees below the minimum requirement of 25 to 35 degrees. The fuel flow control unit began fuel flow at 18 degrees of lever travel. The manual override was dissembled and it was found that the plunger, which compresses the bellows, was allowed to contact the bellows prior to the required degrees of travel.

In review of the Pratt & Whitney Canada service information letter it states: The Cessna Caravan 208/208B aircraft is equipped with a fuel control incorporating an emergency manual override system which is intended to be used in the event of a loss of Power Lever control due to loss of air pressure to the Fuel Control Unit during flight. The Emergency Power Lever does not duplicate the function of the Power Lever Assembly and should not be used as an optional means of controlling the engine. It must be left in the "Normal" position during all normal engine operation.

Review of the pilot's operating handbook emergency procedures states: When using the emergency power lever, monitor gas generator RPM when reducing power near idle, to keep it from decreasing below 65% in flight. The emergency power lever may have a dead band, such that no engine response is observed during the initial forward travel from idle position.

Aircraft

Registration
N738FX
Reported as
Cessna 208B
Category
Airplane
Damage
Minor damage
Flight
Instructional · Part 91
Operator
Federal Express Corporation, doing business as Federal Express Corporation
Departed
MEM · Memphis, TN

Matched to the registry by N-number and the event date; the registry’s history has gaps, so older matches can be wrong. Compare the reported make and model.

Flight crew · 2

As NTSB recorded them. NTSB leaves out names.

Role
Pilot
Injuries
None
Role
Co-pilot
Injuries
None

Weather

Conditions
Visual (VMC)
Wind
0° at 0 knots
Visibility
10 statute miles
Temperature
61 °F, dew point 43 °F
Altimeter
30.12 inHg
Observed at
MEM

Other investigations on N738FX · 1

Matched to the same aircraft by N-number and date.