- Date
- August 28, 1999, 13:00 local (18:00 UTC)
- Place
- San Antonio, TX
- Injuries
- 1 serious
- Damage
- Substantial damage
- Phase of flight
- Approach
- Aircraft
- N103MSBurkhart Grob 103C
- Weather
- Visual (VMC) · Day
- Status
- Completed · report December 4, 2000
- Report
- Approved by Office Director
- FAA report
- 19990828036779A
- Case key
- 47199
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 failure to attain proper runway alignment of the glider resulting in failure to maintain obstacle clearance. A factor was the high density altitude.
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.
Analysis
The wing of the glider struck a tree when the solo student pilot was correcting the flight path to align the glider with the runway centerline during the final approach. The density altitude was calculated at 4,215 feet. The student pilot had 15.2 hours of total flight time in gliders. He was endorsed for solo flight and had 2.4 hours of solo flight time in the glider. The operator reported that the accident could have been prevented by 'maintain[ing] adequate clearance over obstacles.'
Factual narrative
On August 28, 1999, at 1300 central daylight time, a Grob 103C glider, N103MS, struck a tree during the final approach to runway 17 at the Boerne Stage Field Airport near San Antonio, Texas. The glider was owned and operated by Alamo Aerodyne Corporation, San Antonio, Texas, under 14 Code of Federal Regulations (CFR) Part 91. The solo student pilot received serious injuries and the glider sustained substantial damage. Visual meteorological conditions prevailed for the local solo instructional flight and a flight plan was not filed. The flight departed the Boerne Stage Field Airport at 1200.
Witnesses and local authorities reported that the student pilot, while turning final approach, over shot the runway. The pilot was correcting the flight path toward the runway when the right wing struck a tree approximately 5 1/2 inches in diameter. The glider pivoted around the tree and stuck the ground in a nose down attitude. The glider came to rest approximately 300 feet short of the runway.
The FAA inspector and the glider owner examined the glider and found that the inboard 18 to 24 inches of the right wing was damaged and the forward cabin was crushed. Approximately 4 1/2 feet of the outboard right wing was found separated from the glider. The student pilot had 15.2 hours of total flight time in gliders. The student was endorsed for solo flight and had 2.4 hours of solo flight time in the glider.
On the Pilot/Operator Aircraft Accident Report, NTSB Form 6120.1/2, the operator reported that the accident could have been prevented by "maintain[ing] adequate clearance over obstacles."
The National Weather Service observation for San Antonio, Texas, (located 13 nautical miles west of the accident site), at 1255 was 96 degrees Fahrenheit with an altimeter setting of 29.90 inches. The NTSB investigator-in-charge calculated the density altitude at 4,215 feet.
Aircraft
- Registration
- N103MS
- Reported as
- Burkhart Grob 103C
- Category
- Glider
- Serial number
- 34-756
- Airframe hours
- 1,049
- Engine
- unknown
- Damage
- Substantial damage
- Flight
- Instructional · Part 91
- Registered owner
- Bob Bruce
- Airworthiness certificate
- Standard, Aerobatic
- Last inspection
- Annual · June 4, 1999 · 85 hours before
- Departed
- 5C1
- Airport
- 5C1 · Boerne Stage Field, runway 17, 3,400 × 40 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
- 56
- Certificate
- Student
- Medical
- Unknown, Unknown
- Seat
- Front
- Flight hours
- 15 total · 15 in this make and model · 2 as pilot in command · 15 in the last 90 days
Weather
- Conditions
- Visual (VMC) · Day
- Wind
- 160° at 10 knots
- Visibility
- 10 statute miles
- Lowest ceiling
- None
- Temperature
- 97 °F, dew point 63 °F
- Altimeter
- 29.00 inHg
- Observed at
- SAT, 13 nm away
FAA reports on this event · 1
The FAA’s own accident and incident reports, matched to the aircraft by N-number and date.
Other investigations on N103MS · 1
Matched to the same aircraft by N-number and date.