IAD02LA071

NTSB accident investigation · Burkhart Grob G103 Twin Astir · Unionville, PA · July 5, 2002

Accident · No injuriesLimited investigationFinal report
Date
July 5, 2002, 14:00 local (18:00 UTC)
Place
Unionville, PA
Injuries
2 uninjured
Damage
Substantial damage
Phase of flight
Approach
Aircraft
N4446WBurkhart Grob G103 Twin Astir
Weather
Visual (VMC) · Day
Status
Completed · report August 26, 2003
Report
Approved by Office Director
Parties
FAA/FSDO
FAA report
20020705021479A
Case key
55171

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 evasive maneuver to avoid a collision with a departing airplane, which resulted in a landing short of the runway. A factor was the pilot's decision to land on the runway opposite the one in use.

Sequence of events

NTSB’s coding before 2008: each occurrence and phase of flight, and the causes and factors under it. The codes are defined in NTSB’s coding manual.

Abrupt maneuverApproach - vfr pattern - final approach
Evasive maneuver - initiatedPilot in commandCause
Wrong runway - selectedPilot in commandFactor
UndershootApproach - vfr pattern - final approach
On ground/water encounter with terrain/waterLanding
Terrain condition - crop
Terrain condition - ditch

Analysis

While on a left downwind for runway 07, the glider pilot saw a tow plane and glider departing runway 25. The pilot had elected to land on runway 07 because it was the runway he had used to depart earlier, but the winds had changed and the runway in use at the time was runway 25. When he turned on to final approach, the pilot realized he was getting close to the tow plane, and ducked under it to avoid a collision. The glider landed short of the runway, into a field with crops, and subsequently went into a ditch.

Factual narrative

On July 5, 2002, about 1400 eastern daylight time, a Burkhart Grob G103 Twin Astir glider, N4446W, was substantially damaged after it landed short of runway 07 at the Ridge Soaring Gliderport (79N) Unionville, Pennsylvania. The certificated commercial pilot and the passenger were not injured. Visual meteorological conditions prevailed and no flight plan was filed for the local personal flight conducted under 14 CFR Part 91.

In a written statement, the pilot stated that when he was on left downwind for runway 07, he saw a tow plane and a glider taking off on runway 25. The pilot had elected to land on runway 07 because it was the runway he had used to depart earlier, but the winds had changed and the runway in use at the time was runway 25. When he turned on final approach, the pilot realized he was getting close to the tow plane, and ducked under it to avoid a collision. The avoidance maneuver resulted in the glider landing short of the runway, and subsequently colliding with a ditch.

A witness observed the glider when it was on short final approach to runway 07. He said the glider appeared low and touched down short of the runway in a field with crops about 2 1/2 feet high. The glider traveled about 20 feet, then hit a ditch that separated the field from the approach end of runway 07. The left wing of the glider came up and the glider pivoted on the right wing. The tail boom fractured, but remained attached to the airframe by pushrods.

The witness also noted that the winds were from the northwest at 5 to 10 knots.

The pilot reported a total of 8,000 flight hours, of which, 300 hours were in gliders. He also reported that there were no mechanical anomalies with the glider.

Two Federal Aviation Administration (FAA) inspectors performed an examination of the glider. According to an inspector, the fuselage was fractured aft of the wings.

Weather at University Park Airport, State College, Pennsylvania, 4 nm southeast, at 1347, included winds from 360 degrees at 8 knots, and visibility 20 statute miles.

Aircraft

Registration
N4446W
Reported as
Burkhart Grob G103 Twin Astir
Category
Glider
Serial number
3822-K-81
Engine
Damage
Substantial damage
Flight
Personal · Part 91
Registered owner
Knauff And Grove Inc
Airworthiness certificate
Standard, Normal
Departed
79N · Unionville, PA
Airport
79N · Ridge Soaring Glideport, runway 07, 3,325 × 100 ft, asphalt

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
62
Injuries
None
Certificate
Private
Airplane ratings
Multi-engine land, Single-engine land
Instrument ratings
Airplane
Medical
Class 3, Valid Medical--w/ waivers/lim
Last flight review
May 8, 2002
Flight hours
8,000 total

Weather

Conditions
Visual (VMC) · Day
Wind
360° at 8 knots
Visibility
20 statute miles
Lowest ceiling
None
Temperature
79 °F, dew point 50 °F
Altimeter
30.12 inHg
Observed at
UNV, 4 nm away

Docket · 3

The files NTSB released with the investigation on June 24, 2003, on NTSB’s docket system: statements, records, photos and specialists’ reports. 713 KB 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.