NYC08LA168

NTSB accident investigation · Let Blanik L-13 · Dansville, NY · April 19, 2008

Accident · No injuriesLimited investigationFinal report
Date
April 19, 2008, 16:00 local (20:00 UTC)
Place
Dansville, NY
Injuries
2 uninjured
Damage
Substantial damage
Phase of flight
Landing
Aircraft
N90870Let Blanik L-13
Defining event
Landing: Landing area undershoot
Weather
Visual (VMC) · Day
Status
Completed · report March 5, 2009
Report
Approved by Office Director
Parties
FAA/FSDO
FAA report
20080419843119A
Case key
67880

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

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Probable cause

The pilot's failure to attain the proper glide path and the flight instructor's delayed remedial action. Contributing to the accident was the encountered headwind.

Findings · 4

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.

Performance/control parameters: descent/approach/glide pathAircraft › Aircraft oper/perf/capability · Not attained/maintainedLet BLANIK L-13: 2 casesAll aircraft: 809 casesProbable cause
Use of equip/info: aircraft controlPersonnel issues › Task performance · PilotLet BLANIK L-13: 1 caseAll aircraft: 9,295 casesProbable cause
Action: delayed actionPersonnel issues › Action/decision · Instructor/check pilotLet BLANIK L-13: 1 caseAll aircraft: 894 casesProbable cause
WindEnvironmental issues › Conditions/weather/phenomena · Effect on operationLet BLANIK L-13: 1 caseAll aircraft: 110 casesProbable cause

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

The flight instructor was conducting a glider familiarization flight with the private pilot, who had not flown in a glider for about 3 years. The private pilot entered the traffic pattern for the grass landing area adjacent to runway 14. The flight instructor stated that the private pilot was "a little reluctant" to remove the dive brakes and that the instructor removed them while on final approach at 600 feet above ground level. He further stated that the glider encountered a wind gradient that substantially reduced the glider's glide ratio. The glider subsequently landed short of the desired touchdown point and the left wing struck a tree. The glider came to rest about 100 feet before the runway. The private pilot stated that she felt the glider was "too high" until she turned onto the final approach path and realized it was actually "too low." Winds reported at the airport about the time of the accident were from 140 degrees at 15 knots.

Factual narrative

On April 19, 2008, about 1600 eastern daylight time, a Let Blanik L-13 glider, N90870, was substantially damaged when it impacted terrain while landing at the Dansville Municipal Airport (DSV), Dansville, New York. The certificated flight instructor (CFI) and the certificated private pilot were not injured. Visual meteorological conditions prevailed and no flight plan had been filed for the local instructional flight conducted under 14 Code of Federal Regulations Part 91.

The flight instructor was conducting a familiarization flight with the private pilot, who had not flown in a glider for about 3 years.

According to the CFI, the glider was towed to an altitude of the 2,000 feet and released. The private pilot was flying and subsequently entered the traffic pattern for the grass landing area adjacent to runway 14, a 3,500-foot-long, by 100-foot-wide, asphalt runway. The turn from the base leg to the final approach course was performed at an altitude of approximately 700 feet above ground level (agl). The CFI stated that the private pilot was "a little reluctant" to remove the dive brakes and he removed them at 600 feet agl. He further stated:

"At this point in the flight the runway touchdown point appeared ok, so we continued. As we approached approximately 200 [feet] agl we began to sink, so I was forced to take over the controls. We encountered a wind gradient which substantially reduced the glide ratio of the aircraft, which resulted in landing short of the desired touchdown point. The left-hand wind struck a tree which ground-looped the aircraft and we came to a full stop facing the opposite direction of landing...."

The glider came to rest about 100 feet prior to the runway and sustained substantial damage to its left wing and fuselage.

The private pilot stated that she felt the glider was "too high" until she turned onto the final approach path and realized it was "too low."

The CFI reported 7,679 hours of total flight experience which included 145 hours in gliders. The private pilot reported 300 hours of total flight experience, all in gliders. Neither pilot reported any mechanical malfunctions of the glider during the accident flight.

A weather observation taken at DSV, at 1554, reported: wind from 140 degrees at 15 knots, visibility 10 statute miles, clear skies, temperature 29 degrees Celsius (C), dew point 2 degrees C, altimeter 29.82 inches of mercury.

Aircraft

Registration
N90870
Reported as
Let Blanik L-13
Category
Glider
Serial number
025801
Airframe hours
2,299
Damage
Substantial damage
Flight
Instructional · Part 91
Operator
Finger Lakes Soaring Club
Registered owner
Finger Lakes Soaring Club
Airworthiness certificate
Standard, Normal
Last inspection
Annual · April 17, 2008
Departed
DSV · Dansville, NY
Destination
Dansville, NY
Airport
DSV · Dansville Municipal, runway 14, 3,500 × 100 ft, grass/turf

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
Flight instructor
Age
56
Injuries
None
Certificates
Airline transport, Commercial
Airplane ratings
Multi-engine land, Single-engine land
Instrument ratings
Airplane
Medical
Class 1, With waivers/limitations
Last flight review
December 10, 2007
Seat
Rear
Flight hours
7,679 total · 100 in this make and model · 3,493 as pilot in command · 18 in the last 90 days · 12 in the last 30 days · 2 in the last 24 hours
Role
Pilot
Age
61
Injuries
None
Certificate
Private
Seat
Front
Flight hours
300 total

Weather

Conditions
Visual (VMC) · Day
Wind
140° at 15 knots
Visibility
10 statute miles
Lowest ceiling
None
Temperature
84 °F, dew point 36 °F
Altimeter
29.81 inHg
Observed at
DSV

FAA reports on this event · 1

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