Aircraft Accident/Incident Report

Bryce Canyon, Utah 84717
Wednesday, October 15, 1997 10:36 MDT

NTSB Narrative Summary Released at Completion of Accident

The pilot said that smoke began coming into the cockpit and 'I could hardly see the propeller.' He stated that 'at that point, we discovered the indicator light for the cabin door seal pressurization pump was on.' The pilot believes that it had been operating continuously due to an air leak in the system. In order to eliminate electrical power to the pressurization pump, the pilot turned the master switch off. After landing the airplane, the pilot located a fire in the upholstery, which he extinguished. Postincident examination revealed that the aluminum housing of a resistor (inverter) in the cabin door seal pressurization pump (an STC modification) had melted and deformed. Further investigation revealed that the pump unit had not been installed properly due to lack of adequate written instructions. Additionally, the design of the unit did not include a pilot controlled on-off switch, adequate space for cooling during operation, sufficient procedural directions for when the amber caution light comes on, and there was no way to monitor the pumps operating time limitation (10 minutes). It was also determined that the wrong amperage fuse had been installed in the pump system.

NTSB Probable Cause Narrative

The failure of the resistor (inverter) in the door seal pressurization air pump due to continuous operation. Factors were a failure in the door seal pressurization system, its inadequate design by the manufacturer, its inadequate written instructions for installation and operation, and the installation of the improper electrical fuse by unknown persons.

Event Information

Type of Event Incident
Event Date 10/15/1997
Event Day of the Week Wednesday
Time of Event 1036
Event Time Zone Mountain Daylight Time
Event City BRYCE CANYON
Event State UTAH
Event Country --
Zipcode of the event site 84717
Event Date Year 1997
Event Date Month 10
MidAir Collision Indicator No
On Ground Collision occurred ? No
Event Location Latitude
Event Location Longitude
Event Location Airport
Event Location Nearest Airport ID
Indicates whether the acc/inc occurred off or on an airport Off Airport/Airstrip
Distance from airport in statute miles --
Degrees magnetic from airport --
Airport Elevation --
Weather Briefing Completeness Not pertinent
Investigator's weather source Pilot
Time of the weather observation 0
Direction of event from weather observation facility (degrees) 0
Weather Observation Facility ID
Elevation of weather observation facility 0
Distance of event from weather observation facility (units?) 0
Time Zone of the weather observation
Lighting Conditions Day
Lowest Ceiling Height 0
Lowest Non-Ceiling Height 0
Sky/Lowest/Cloud Conditions Clear
Sky Condition for Lowest Ceiling None
Visibility Runway Visual Range (Feet) 0
Visibility Runway Visual Value (Statute Miles) 0
Visibility (Statute Miles) 90
Air Temperature at event time (in degrees celsius) 24
Dew Point at event time (in degress fahrenheit) --
Wind Direction (degrees magnetic) 90
Variable Wind Indicator Unknown
Wind Speed (knots) 0
Wind Velocity Indicator Light and Variable
Wind Gust Indicator Not Gusting
Wind Gust (knots) 0
Altimeter Setting at event time (in. Hg) --
Density Altitude (feet) --
Intensity of Precipitation Unknown
METAR weather report --
Event Highest Injury None
On Ground, Fatal Injuries 0
On Ground, Minor Injuries 0
On Ground, Serious Injuries 0
Injury Total Fatal --
Injury Total Minor --
Injury Total None 2
Injury Total Serious --
Injury Total All --
Investigating Agency NTSB
NTSB Docket Number (internal use) 1680
NTSB Notification Source --
NTSB Notification Date Nov 13 1997 12:00AM
NTSB Notification Time 1400
Fiche Number and/or location -used to find docket information IMAGE
Date of most recent change to record Aug 16 2001 5:10PM
User who most recently changed record MONR
Basic weather conditions Visual Meteorological Cond
FAA District Office --

Aircraft Involved

Aircraft #1

Aircraft Registration Number N731NX
NTSB Number FTW98TA051
Missing Aircraft Indicator N
Federal Aviation Reg. Part Part 91: General Aviation
Type of Flight Plan filed VFR
Flight plan Was Activated? --
Damage Minor
Aircraft Fire In-flight
Aircraft Explosion None
Aircraft Manufacturer's Full Name Cessna
Aircraft Model P210N
Aircraft Series Identifier P210N
Aircraft Serial Number P21000515
Certified Max Gross Weight 4000
Aircraft Category Airplane
Aircraft Registration Class U.S. Registered/U.S. Soil
Aircraft is a homebuilt? No
Flight Crew Seats --
Cabin Crew Seats --
Passenger Seats --
Total number of seats on the aircraft 5
Number of Engines 1
Fixed gear or retractable gear Retractable
Aircraft, Type of Last Inspection Annual
Date of Last Inspection Jul 30 1997 12:00AM
Airframe hours since last inspection 59
Airframe Hours 5510
ELT Installed Yes
ELT Activated No
ELT Aided Location of Event Site Unknown
ELT Type --
Aircraft Owner Name MESA COUNTY
Aircraft Owner Street Address P.O. BOX 20000
Aircraft Owner City GRAND JUNCTION
Aircraft Owner State CO
Aircraft Owner Country
Aircraft Owner Zipcode 81502
Operator is an individual? --
Operator Name
Operator Same as Owner? Yes
Operator Is Doing Business As --
Operator Address Same as Owner? Yes
Operator Street Address
Operator City
Operator State
Operator Country
Operator Zip code
Operator Code
Owner has at least one certificate None
Other Operator of large aircraft? No
Certified for Part 133 or 137 Operation Unknown
Operator Certificate Number --
Indicates whether an air carrier operation was scheduled or not --
Indicates Domestic or International Flight --
Operator carrying Pax/Cargo/Mail --
Type of Flying (Per_Bus / Primary) Public Use
Second Pilot on Board No
Departure Point Same as Event No
Departure Airport Code GJT
Departure City GRAND JUNCTION
Departure State CO
Departure Country
Departure Time 930
Departure Time Zone MDT
Destination Same as Local Flt crash at destination city
Destination Airport Code BCE
Destination City
Destination State UT
Destination Country
Specific Phase of Flight Cruise
Report sent to ICAO? --
Evacuation occurred --
Date of most recent change to record Jan 2 2001 10:34AM
User who most recently changed record dbo
Since inspection or accident --
Event Location Runway Number and Location 0
Runway Length --
Runway Width --
Sight Seeing flight No
Air Medical Flight No
Medical Flight --