Misrigged Pennsylvania Wing Glider Crashes

Schweizer SGS 2-33A, N2045TSchweizer SGS 2-33A, N2045T

By NTSB | FAA Aviation Accident Database

PRELIMINARY REPORT
On May 4, 2013, about 10:50 eastern daylight time, a Schweizer SGS 2-33A glider, N2045T, registered to and operated by the Civil Air Patrol (CAP), was substantially damaged when it impacted trees and terrain, near Erwinna, Pennsylvania. The commercial pilot was seriously injured. Visual meteorological conditions prevailed, and no flight plan was filed. The maintenance test flight was conducted under the provisions of 14 Code of Federal Regulations Part 91. The flight originated from Vansant Airport (9N1), Erwinna, Pennsylvania about 1045. The pilot was critically injured and was unable to provide any information about the accident. According to the tow plane pilot, the glider pilot intended to practice stalls after being towed to an altitude of 3,000 feet mean sea level.

After takeoff from runway 07, the tow plane pilot observed the glider yaw to the left, then right, and left again. For most of the flight, the glider appeared to be above the normal tow position with its nose pointed 45 degrees to the right. Approximately 400 feet above ground level, the glider pilot released the tow line and made a left turn. The tow plane pilot observed the glider turn about 180 degrees, where it impacted trees with its right wing, pitched down, and impacted terrain. Post accident examination of the wreckage by a Federal Aviation Administration (FAA) inspector revealed that the rudder controls were rigged backwards. According to FAA records, the pilot held a commercial pilot and flight instructor certificates, with ratings for airplane single-engine land, instrument airplane, and glider. His most recent FAA second class medical certificate was issued on August 30, 2011.

As of April 15, 2013, the pilot reported 13,290 total hours of flight experience; of which, 8,960 of those hours were in gliders. The two-seat glider was manufactured in 1977. Review of the glider’s logbooks revealed that its most recent annual inspection was completed on May 1, 2013. At the time of inspection, the glider had accumulated 13,626 total hours. According to the mechanic, who performed the annual inspection, the glider was scheduled for a total restoration in the fall of 2012. Due to lack of funding, the restoration never took place and the disassembled glider sat on a trailer through the winter.

During the spring of 2013, the glider was reassembled and an annual inspection was performed. The rudder had been removed at an earlier date due to previous damage, repaired, and re-installed prior to the annual inspection. The flight was the first flight following the most recent annual inspection. A mechanic performed a flight control check after the annual inspection. According to the mechanic, he stood at the rear of the glider and held the rudder while another pilot sat in the cockpit and moved the pedals. The mechanic could not see which pedal the pilot was pushing and did not verbally confirm the position of the pedals. The 2-33 Sailplane Flight-Erection-Maintenance manual pre-flight inspection checklist included inspecting the condition, operation, security of attachment and/or other signs of failure of the rudder and other components.

FINAL REPORT
The glider pilot intended to practice stalls after being towed to an altitude of 3,000 feet mean sea level. Shortly after takeoff, the tow pilot observed the glider yaw left, then right, and then left again. He added that, for most of the tow, the glider appeared to be above the normal tow position with its nose pointed 45 degrees right. About 400 feet above ground level, the glider pilot released the tow line and the glider turned about 180 degrees left; its right wing then impacted trees and the glider pitched down and impacted terrain. Post accident examination of the wreckage revealed that the rudder control cables were rigged backward. The accident flight was the first flight following the glider’s most recent annual inspection.

Before the annual inspection, the rudder had been removed for repair then re-installed. The mechanic who conducted a flight control check after the annual inspection with assistance from another pilot seated in the cockpit stated that he confirmed movement of the rudder while at the rear of the glider; however, he did not see which pedal the pilot was pushing and did not verbally confirm the corresponding position of the rudder pedals. If the pilot had conducted a thorough pre-flight inspection, he should have been able to detect that the rudder control cables were rigged backward.

CAUSE REPORT
The pilot’s loss of glider control due to improper rigging of the rudder control cables, the mechanic’s inadequate flight control checks following the glider’s most recent annual inspection and the pilot’s failure to perform a thorough pre-flight inspection.

2 Comments on "Misrigged Pennsylvania Wing Glider Crashes"

  1. as an addendum to my previous anon comment on the 2013 May 04 glider accident.

    While the NTSB Pilot/Operator Report of Accident did not identify CAP as the owner of the aircraft, ownership was mentioned in three documents in the docket, as well as in the NTSB final report for the accident. The absence “CAP” in the signature line title for the NTSB Pilot/Operator report may just be an oversight, or it may be systemic. A more recent CAP glider accident likewise made no mention of CAP in the Pilot/Operator Report. In that accident (also discussed on the AuxBeacon site) details in the docket were sparse.

  2. FWIW, it appears to me that the amount of outrage is excessive regarding the glider mishap involving a misrigged rudder. The PIC committed a very serious error in his failure to do a thorough pre-flight control check. He failed not once, but twice. First, when conducting the post maintenance, acceptance check with an assistant, and again when he climbed into the cockpit and did not confirm by clearly saying (and receiving confirmation) Rudder RIGHT, Rudder LEFT. The maintenance tech also failed to conduct an effective control check after having worked on the rudder and control cables. FWIW, I am aware of several other shops where similar errors were made. And the NTSB accident db has several examples of where expectation bias by professional pilots (test pilots with lots of ratings and decades of experience, career pilots working for State or Federal aviation organizations, and CFIs, and others) prevented many other otherwise competent pilots from detecting control misrigging in a variety of aircraft. This one accident is not damning, but does indicate CAP maintenance officers are in some circumstances ill equipped to fulfill their role. FWIW, I am aware of a few non-accident maintenance failures where mechanics in otherwise very good shops offered equally terrible advice to Unit Maintenance Officers that resulted in engine issues. A bigger problem is the unknown-to-me, but likely large number of cylinder failures that probably result from pilot mismanagement of CHTs in CAP aircraft. Fortunately, those problems are often caught in the 100 hour or by alert pilots during normal operations.

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