N2574V

Substantial
Minor

Cessna 170 S/N: 18111

Accident Details

Date
Sunday, August 16, 1998
NTSB Number
FTW98LA360
Location
BOULDER, CO
Event ID
20001211X10853
Coordinates
39.989913, -105.090682
Aircraft Damage
Substantial
Highest Injury
Minor
Fatalities
0
Serious Injuries
0
Minor Injuries
3
Uninjured
0
Total Aboard
3

Probable Cause and Findings

The pilot's intentional ground loop and his inadequate compensation for the wind condition. A contributng factor was crosswinds.

Aircraft Information

Registration
N2574V
Make
CESSNA
Serial Number
18111
Engine Type
Reciprocating
Model / ICAO
170 C170
Aircraft Type
Fixed Wing Single Engine
No. of Engines
1

Registered Owner (Historical)

Name
TWOMBLY ERIC D
Address
PO BOX 811
Status
Deregistered
City
HALFWAY
State / Zip Code
OR 97834-0811
Country
United States

Analysis

On August 16, 1998, approximately 1630 mountain daylight time, a Cessna 170, N2574V, was substantially damaged following an intentional ground loop initiated by the pilot at Boulder Municipal Airport, Boulder, Colorado. The private pilot and his two passengers received minor injuries. The airplane was being operated by the pilot under Title 14 CFR Part 91. Visual meteorological conditions prevailed for the personal cross-country flight which originated from Ogallala, Nebraska, approximately 2 hours before the accident. A VFR flight plan had been filed.

The pilot reported that as he approached Boulder Municipal Airport (elevation 5,288 feet, density altitude 7,807 feet) for a full stop landing, he heard the pilot of another airplane which was landing on runway 8 report that he had a tail wind during his landing. The pilot said that he "noticed the wind sock on the east end of the runway was standing straight out in a direction that appeared to be 180 degrees." The pilot landed on runway 26, but reported having difficulty keeping N2574V aligned with the centerline. He said, "I immediately determined to execute a go around. I had trimmed nose up for landing so I was attempting to get the nose down but was also buffeted by very turbulent winds [coming] over the hangers to the south." The pilot said that he believed it was safer to perform a ground loop then to go in the lake at the west end of the runway. He said, "I didn't feel at the time I stood any chance of gaining airspeed to execute a climb."

One witness reported that immediately after the accident, they noticed that the wind was coming from the northeast. The winds at Jefferson County Airport (BJC), which is 9 nm southeast of Boulder Municipal Airport, were 180 degrees and 13 knots at 1549. At 1655, the winds at BJC were 150 degrees and 11 knots gusting to 20 knots.

Data Source

Data provided by the National Transportation Safety Board (NTSB). For more information on this event, visit the NTSB Records Search website. NTSB# FTW98LA360