ERA10CA260

NTSB accident investigation · Schleicher ASW-20C · Unionville, PA · May 9, 2010

Accident · Serious injuriesData collectionFinal report
Date
May 9, 2010, 12:44 local (16:44 UTC)
Place
Unionville, PA
Injuries
1 serious
Damage
Substantial damage
Phase of flight
Maneuvering
Aircraft
N6BFSchleicher ASW-20C
Defining event
Maneuvering-low-alt flying: Loss of lift
Weather
Visual (VMC) · Day
Status
Completed · report April 12, 2011
Report
Approved by Office Director
NTSB office
Eastern Region Aviation
Parties
FAA/FSDO
FAA report
20100509034519A
Case key
75983

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

On this page

Probable cause

The pilot's lack of remedial action in response to a loss of altitude, which led to a forced landing in unsuitable terrain.

Findings · 2

NTSB’s coded findings. Those marked are part of the probable cause; the rest are factors or other findings. Under each, the cases with the same finding.

Action: lack of actionPersonnel issues › Action/decision · PilotSchleicher ASW-20C: 1 caseAll aircraft: 792 casesProbable cause
Wind: downdraftEnvironmental issues › Conditions/weather/phenomena · Effect on equipmentSchleicher ASW-20C: 1 caseAll aircraft: 178 cases

Sequence of events

The events NTSB coded, in order, by phase of flight. The defining event is the one that best describes the accident. Under each, the cases with the same event anywhere in their sequence.

Analysis

According to the glider pilot, the flight was intended as a local recreational flight. He planned to climb via thermals to get across a five-mile gap between ridges, but was unable to gain altitude. He then attempted to turn to a "spur" that was separate from the main ridge to gain lift, but while performing the maneuvers the glider continued to lose altitude in a downdraft. The glider subsequently impacted trees and came to rest inverted, seriously injuring the pilot. The pilot reported that there were no mechanical problems with the glider. He stated that, in retrospect, he should have released the 10 gallons of water ballast in each wing and deployed positive flaps. A weather observation taken 35 miles from the accident site, approximately at the time of the accident, recorded the wind from 301 degrees at 13 knots, gusting to 20 knots.

Factual narrative

According to the pilot, this was intended as an “out & return” recreational flight. He intended to climb via thermals to get across a five-mile gap between ridges, but was unable to gain altitude. He then attempted to turn to a “spur” that was separate from the main ridge to gain lift, but while performing the maneuvers, the glider continued to lose altitude “in sinking air.” The glider subsequently impacted trees and came to rest inverted, seriously injuring the pilot. The pilot reported that there were no mechanical problems with the glider. He stated that in retrospect, he should have released the 10 gallons of water ballast in each wing and deployed positive flaps. A weather observation taken approximately at the time of the accident, 35 miles from the accident site, recorded the wind as 290 degrees at 13 knots, gusting 20 knots.

Aircraft

Registration
N6BF
Reported as
Schleicher ASW-20C
Category
Glider
Serial number
20832
Airframe hours
1,000
Damage
Substantial damage
Flight
Personal · Part 91
Operator
Dutka Leslie A
Registered owner
Dutka Leslie A
Airworthiness certificate
Special, Experimental (Special)
Last inspection
Annual · April 20, 2010
Departed
79N · Unionville, PA
Destination
79N · Unionville, PA

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

As NTSB recorded them. NTSB leaves out names.

Role
Pilot
Age
66
Injuries
Serious
Certificate
Private
Airplane ratings
Single-engine land
Instrument ratings
Airplane
Medical
Class 3, With waivers/limitations
Last flight review
January 23, 2010
Seat
Single
Flight hours
2,500 total · 500 in this make and model · 20 in the last 90 days · 4 in the last 30 days

Weather

Conditions
Visual (VMC) · Day
Wind
290° at 13 knots, gusting 20
Visibility
10 statute miles
Lowest ceiling
4,400 ft overcast
Temperature
43 °F, dew point 28 °F
Altimeter
30.09 inHg
Observed at
KUNV, 35 nm away

Docket · 4

The files NTSB released with the investigation on November 17, 2010, on NTSB’s docket system: statements, records, photos and specialists’ reports. 1.0 MB in all.

FAA reports on this event · 1

The FAA’s own accident and incident reports, matched to the aircraft by N-number and date.