# NTSB IAD03LA046: Schweizer SGS 2-33A, N1241S, Sterling, MA, April 19, 2003 - Type: NTSB accident investigation - Classification: Accident · No injuries · Limited investigation · Final report - Date: April 19, 2003, 16:30 local (20:30 UTC) - Place: Sterling, MA - Coordinates: 42.425834, -71.792778 - Nearby events: https://openairdocs.org/map.md?lat=42.4258&lon=-71.7928&mi=10 - Phase of flight: [Approach](https://openairdocs.org/ntsb-phases/500) (OpenAirDocs' grouping) - Highest injury: No injuries - Injuries: 1 uninjured - Status: Completed, report January 24, 2005 - Report: Approved by Office Director - Parties: Windsor Locks FSDO - NTSB case key (mKey): 56800 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=IAD03LA046 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/56800/pdf - Page: https://openairdocs.org/ntsb/IAD03LA046 ## Probable cause The student pilot's misjudgment of his traffic pattern altitudes, which resulted in a premature descent into a tree. ## Sequence of events In NTSB's coding before 2008 (https://www.ntsb.gov/GILS/Documents/codman.pdf). - In flight collision with object, approach - vfr pattern - base turn - altitude - misjudged, pilot in command (cause) - object - tree(s) - descent - premature, pilot in command ## Analysis After practicing maneuvers at 5,000 feet, the student pilot returned to the airport. He entered the downwind leg at an altitude about 850 feet above the ground. He continued to descend, using airbrakes, until he realized he was too low, about 250 feet above the ground. He then tried to "cut the corners" of the traffic pattern in an attempt to make it to the runway; however, the glider's right wing impacted a tree. ## Factual narrative On April 19, 2003, about 1630 eastern daylight time, a Schweizer 2-33A glider, N1241S, was substantially damaged when it impacted trees while on approach to Sterling Airport (3B3), Sterling, Massachusetts. The certificated student pilot was not injured. Visual meteorological conditions prevailed, and no flight plan had been filed for the local instructional flight conducted under 14 CFR Part 91. In a written statement, the student pilot said that on the morning of the accident, he flew with his flight instructor, and received a solo endorsement. Later that day, he departed on a solo flight to practice maneuvers in preparation for his private pilot certificate. After being towed to an altitude of 5,000 feet, the student pilot practiced flight maneuvers, then returned to the airport. He entered the downwind leg for runway 16 at an altitude of 1,300 feet mean sea level (msl). He continued to descend, using airbrakes, until he realized he was too low, about 700 feet msl. The student pilot then "cut the corners" of the traffic pattern in an attempt to make it to the runway, when the right wing impacted a tree. Several people who witnessed the glider on the downwind leg, said it was at a "very low" altitude. One of the witnesses, who was concerned about the glider's low altitude on the downwind leg, dialed 911 on his cell phone. He continued to watch the glider as it turned onto the base leg of the traffic pattern, and impacted a tree. After observing the accident, the witness completed the call to 911. A Federal Aviation Administration (FAA) inspector performed an on-scene examination of the glider. The examination revealed that the fuselage was twisted aft of the cockpit, the left and right wing sustained substantial damage, and the right wing spar was twisted. The altimeter indicated 500 feet. Sterling Airport was an uncontrolled field. Runway 16 was a 3,086-foot-long, 40-foot-wide, asphalt runway. According to published airport information, there were 23-foot trees located 300 feet from the approach end of the runway. The field elevation was 459 feet. The pilot reported a total of 27 hours of flight time, all in gliders. Twelve of these hours were in make and model. In addition, when asked how this accident could have been prevented, the student pilot said, "I had just flown the glider and did not check the altimeter for the second flight. I should have. When realizing I was too low, I cut corners to get back to the airfield. I should have not cut so tight and should have flown a wider pattern. I made two mistakes". Weather at Fitchburg Municipal Airport, Fitchburg (FIT), Massachusetts, 7 miles north of Sterling Airport, at 1652, included winds from 090 at 8 knots, visibility 10 statute miles, and an overcast ceiling at 4,100 feet. The temperature was 57 degrees F and the dew point was 27 degrees F. The barometric setting was 30.40 inches HG. ## Aircraft - Registration: [N1241S](https://openairdocs.org/deregistered/N1241S-2006-08-15), registration cancelled 2006-08-15, S/N 223, built 1971 (OpenAirDocs) - Reported make and model: Schweizer SGS 2-33A - Registry model: [Schweizer SGS 2-33A](https://openairdocs.org/model/schweizer-sgs-2-33a) (registry code 8051606) (OpenAirDocs) - Registry engine: [NONE](https://openairdocs.org/engine/none) (registry code 00000, none) (OpenAirDocs) - Category: Glider - Serial number: 223 - Damage: Substantial damage - Flight: Instructional, Part 91 - Registered owner: Greater Boston Soaring Club Inc - Airworthiness certificate: Standard, Normal - Departed: 3B3, Sterling, MA - Airport: 3B3, Sterling Airport, runway 16, 3,086 × 40 ft, asphalt ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 60; injuries: none; student; seat: front; flight hours: 27 total, 12 in this make and model, 18 as pilot in command, 1 in the last 90 days, 1 in the last 30 days, 1 in the last 24 hours ## Weather - Conditions: Visual (VMC), Day - Wind: 90° at 8 knots - Visibility: 10 statute miles - Lowest ceiling: 4,100 ft overcast - Temperature: 57 °F, dew point 27 °F - Altimeter: 30.39 inHg - Observed at: FIT, 7 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 (OpenAirDocs). - [Accident 20030419005539A](https://openairdocs.org/incident/20030419005539A), Apr 19, 2003: Scwzer SGS233A, Sterling, MA, Substantial damage. (-23) Student pilot made right downwind to runway 16 at Sterling Airport at too low an altitude. Pilot turned right base leg cutting corner of normal traffic… ## Other investigations on N1241S (2) From the NTSB's public API. Aircraft are matched to registry aircraft by N-number and event date, checked against the reported serial number, make and model; the registry's history has gaps, so older matches can be wrong. Compare the reported make and model. - [NTSB NYC74DHA07](https://openairdocs.org/ntsb/NYC74DHA07), Aug 24, 1973: Schweizer SGS233 (N1241S), Erwinna, PA, substantial damage - [NTSB NYC73DHA02](https://openairdocs.org/ntsb/NYC73DHA02), Jul 15, 1972: Schweizer 233A (N1241S), Erwinna, PA, substantial damage From the NTSB's public API. Aircraft are matched to registry aircraft by N-number and event date, checked against the reported serial number, make and model; the registry's history has gaps, so older matches can be wrong. Compare the reported make and model. --- OpenAirDocs.org is an independent research project of [Contrail Labs](https://contraillabs.com/). It is not affiliated with the FAA or the NTSB. Source documents are U.S. government works in the public domain.