Potomac Airfield Airport
Aircraft Accident/Incident Report

Friendly, Maryland 20744
Tuesady, September 21, 1999 18:30 EDT

NTSB Narrative Summary Released at Completion of Accident

The flight instructor and private pilot departed on an instrument training flight in IFR conditions. The private pilot performed the takeoff and announced during climbout that the airspeed indicator was inoperative. The flight instructor took control of the airplane and returned for landing. The flight instructor attempted 2 landings and aborted both attempts. On the third attempt, the airplane touched down, overran the runway, and collided with a ditch. Examination of the airplane after the accident revealed an obstructed pitot tube.

NTSB Probable Cause Narrative

The pilot's misjudgment of speed during the landing approach. The inoperative airspeed indicator was a contributing factor.

Event Information

Type of Event Accident
Event Date 9/21/1999
Event Day of the Week Tuesday
Time of Event 1830
Event Time Zone Eastern Daylight Time
Event City FRIENDLY
Event State MARYLAND
Event Country --
Zipcode of the event site 20744
Event Date Year 1999
Event Date Month 9
MidAir Collision Indicator No
On Ground Collision occurred ? No
Event Location Latitude --
Event Location Longitude --
Event Location Airport POTOMAC AIRFIELD
Event Location Nearest Airport ID VKX
Indicates whether the acc/inc occurred off or on an airport On Airport
Distance from airport in statute miles --
Degrees magnetic from airport --
Airport Elevation 115
Weather Briefing Completeness Not pertinent
Investigator's weather source Weather Observation Facility
Time of the weather observation 1834 Eastern Daylight Time
Direction of event from weather observation facility (degrees) 60
Weather Observation Facility ID ADW
Elevation of weather observation facility 0
Distance of event from weather observation facility (units?) 5
Time Zone of the weather observation EDT
Lighting Conditions Day
Lowest Ceiling Height 500
Lowest Non-Ceiling Height 300
Sky/Lowest/Cloud Conditions Scattered
Sky Condition for Lowest Ceiling Broken
Visibility Runway Visual Range (Feet) 0
Visibility Runway Visual Value (Statute Miles) 0
Visibility (Statute Miles) 4
Air Temperature at event time (in degrees celsius) 12
Dew Point at event time (in degress fahrenheit) 12
Wind Direction (degrees magnetic) 330
Variable Wind Indicator Unknown
Wind Speed (knots) 14
Wind Velocity Indicator Unknown
Wind Gust Indicator Not Gusting
Wind Gust (knots) 0
Altimeter Setting at event time (in. Hg) 29
Density Altitude (feet) --
Intensity of Precipitation Light
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) 876
NTSB Notification Source --
NTSB Notification Date Sep 22 1999 12:00AM
NTSB Notification Time 900
Fiche Number and/or location -used to find docket information IMAGE
Date of most recent change to record Nov 4 2009 5:09PM
User who most recently changed record johb
Basic weather conditions Instrument Meteorological Cond
FAA District Office --

Aircraft Involved

Aircraft #1

Aircraft Registration Number N63325
NTSB Number IAD99LA068
Missing Aircraft Indicator N
Federal Aviation Reg. Part Part 91: General Aviation
Type of Flight Plan filed IFR
Flight plan Was Activated? --
Damage Substantial
Aircraft Fire None
Aircraft Explosion None
Aircraft Manufacturer's Full Name Cessna
Aircraft Model 172P
Aircraft Series Identifier 172P
Aircraft Serial Number 17275422
Certified Max Gross Weight 2150
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 4
Number of Engines 1
Fixed gear or retractable gear Fixed
Aircraft, Type of Last Inspection 100 Hour
Date of Last Inspection Sep 1 1999 12:00AM
Airframe hours since last inspection 26
Airframe Hours 9732
ELT Installed Yes
ELT Activated No
ELT Aided Location of Event Site Unknown
ELT Type --
Aircraft Owner Name JAMES DAVIDSON
Aircraft Owner Street Address 802 SOUTH ARLINGTON MILL DR
Aircraft Owner City ARLINGTON
Aircraft Owner State VA
Aircraft Owner Country
Aircraft Owner Zipcode 22204
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) Instructional
Second Pilot on Board Yes
Departure Point Same as Event Yes
Departure Airport Code VKX
Departure City
Departure State
Departure Country
Departure Time 1820
Departure Time Zone EDT
Destination Same as Local Flt dest & departure same, accident can occur anywhere
Destination Airport Code
Destination City
Destination State
Destination Country
Specific Phase of Flight Takeoff
Report sent to ICAO? --
Evacuation occurred --
Date of most recent change to record Apr 20 2001 4:06AM
User who most recently changed record dbo
Since inspection or accident --
Event Location Runway Number and Location 6
Runway Length 2165
Runway Width 40
Sight Seeing flight No
Air Medical Flight No
Medical Flight --