# NTSB NYC04FA223: Aero Commander 112, N1261J, Vieques, PR, February 16, 2004 - Type: NTSB accident investigation - Classification: Accident · Fatal · Field investigation · Final report - Date: February 15, 2004, 21:00 local (Feb 16, 2004, 01:00 UTC) - Place: Vieques, PR - Coordinates: 18.151945, -65.361663 - Nearby events: https://openairdocs.org/map.md?lat=18.1519&lon=-65.3617&mi=10 - Phase of flight: [Enroute](https://openairdocs.org/ntsb-phases/400) (OpenAirDocs' grouping) - Highest injury: Fatal - Injuries: 1 fatal - Status: Completed, report September 26, 2008 - Report: Approved by Office Director - Parties: FAA/FSDO - NTSB case key (mKey): 67830 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=NYC04FA223 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/67830/pdf - Page: https://openairdocs.org/ntsb/NYC04FA223 ## Probable cause The pilot's inadequate preflight and in-flight planning and decision making which resulted in the airplane entering instrument meteorological conditions. Contributing to the accident was the pilot's lack of instrument experience, a vacuum pump failure, and the night lighting conditions. ## Sequence of events In NTSB's coding before 2008 (https://www.ntsb.gov/GILS/Documents/codman.pdf). - Airframe/component/system failure/malfunction, cruise - vacuum system - failure (contributing factor) - Loss of control - in flight, cruise - qualification, pilot in command (contributing factor) - preflight planning/preparation - inadequate, pilot in command (cause) - light condition - dark night (contributing factor) - in-flight planning/decision - inadequate, pilot in command (cause) - vfr flight into imc - performed, pilot in command - In flight collision with terrain/water, descent - uncontrolled - terrain condition - ground ## Analysis While proceeding eastbound at night along the shoreline of an island, the airplane began a rapid spiral descent, and impacted the ground. Despite an extensive search by multiple entities, the airplane remained missing for approximately 4 years; however, when the wreckage was located, there was sufficient evidence to show that the vacuum pump, which powered the attitude indicator and the directional gyro, had failed. Examination of Federal Aviation Administration (FAA) records revealed that the airplane had accrued in excess of 1,224.8 total hours of operation, but no evidence of the vacuum pump ever being overhauled or replaced was discovered. The pilot did not possess an instrument rating, and most likely had not flown at night for approximately 10 years. The airplane was equipped with an autopilot; however, the pilot was reported not to be experienced in its use. Taking into consideration the direction of flight, available weather data, and the lack of ground lights in the area, there would have been no visible horizon forcing the pilot to maintain control of the airplane solely by referencing the flight instruments. It has been well documented that such conditions can result in a myriad of vestibular illusions which can be extremely difficult to overcome. One illusion in particular can cause a pilot to believe the airplane is in level flight, when in reality, it is in a gradual turn. If the airspeed increases, the pilot may experience a postural sensation of a level dive and pull back on the yoke, which tightens the turn. If recovery is not initiated, a steep spiral will develop and continue until the airplane impacts the ground or water. The FAA's Airplane Flying Handbook states that "unless a pilot has many hours of training in instrument flight, flight in reduced visibility or at night when the horizon is not visible should be avoided." FAA Advisory Circular AC 91-75, highlights that pilots tend to rely heavily on the attitude indicator in instrument meteorological conditions, and that vacuum system failures can be a significant cause or contributor to fatal accidents because in most cases the corresponding instruments slowly becomes inaccurate, making the failure difficult to recognize. ## Factual narrative HISTORY OF FLIGHT On February 15, 2004, about 2100 Atlantic Standard Time, an Aero Commander 112, N1261J, was substantially damaged when it impacted the ground, in the Vieques National Wildlife Refuge, Vieques, Puerto Rico. Night visual meteorological conditions prevailed for the flight, which departed Luis Munoz Marin International Airport (TJSJ), San Juan, Puerto Rico at approximately 2030 destined for Henry E. Rohlsen Airport (TISX), St. Croix, United States Virgin Islands. A VFR flight plan was filed and activated for the personal flight conducted under 14 Code of Federal Regulations Part 91. On February 16, 2004, a Federal Aviation Administration (FAA) Air Route Traffic Control Center specialist assigned to the Center Radar Approach Control advised the National Transportation Safety Board that after departure from TJSJ, the accident airplane proceeded southeast, towards the Island of Saint Croix. It then began to descend over the ocean. He stated that as the airplane descended to about 1,000 feet above mean sea level (msl), radar contact was lost, and repeated attempts to contact the airplane were unsuccessful. The airplane failed to arrive at TISX, and was not located at any airport. The airplane was reported overdue about 2145. Search personnel then began an extensive search along the anticipated route of flight that included aircraft and surface vessels. Search efforts were unsuccessful and the search was suspended on February 23, 2004. After the search was suspended, Safety Board radar specialists reviewed the Federal Aviation Administration (FAA) archived radar data, and reported inconsistencies concerning the last reported position of the missing airplane. The Safety Board radar specialists provided an enhanced radar track that matched the accident airplane's departure time, heading and flight route. The radar data included altitude information from the airplane's Mode C transponder. The radar data indicated that a target departed from San Juan, then headed eastbound along the northern shoreline. The target then turned southeast, towards the Island of Vieques, at 3,500 feet msl. As the target progressed eastbound along the northern shoreline of Vieques Island, it turned right, and began a rapid spiral descent. On February 26, 2004, a witness contacted the FAA, and reported that on February 15, 2004 about 2100, he observed a red light falling at a high rate of speed near Vieques Island, which coincided with the Safety Board's enhanced radar track. The witness reported that at the time of the sighting, he and his family were aboard an anchored boat. They were unaware that an airplane was missing until they returned to San Juan, after the search had been suspended. Search personnel from the Vieques Emergency Management, along with family members and friends of the missing pilot, conducted an extensive ground search of the northeastern part of Vieques Island. Search crews reported a thick covering of mangrove trees that hindered the search for the accident airplane. The search was unsuccessful, and the accident airplane and pilot remained missing. On April 16, 2008, a Department of Interior (DOI) United States Fish and Wildlife Service Officer, contacted the Safety Board and advised that the accident airplane had been discovered by explosive ordinance disposal personnel in the United States Navy, Atlantic Fleet Weapons Training Facility's 11,000 acre Eastern Maneuver Area. In the past the facility had been used for weapons training using live ordinance but, at the time of the accident, it had been closed and turned over to the DOI. The accident occurred during the hours of night. The wreckage was located at 18 degrees, 09.111 minutes north latitude, and 65 degrees, 21.698 minutes west longitude. PERSONNEL INFORMATION According to FAA records, the pilot held a private pilot certificate with a rating for airplane single-engine-land and did not possess an instrument rating. He reported 900 total hours of flight experience on his most recent application for an FAA first-class medical certificate, dated July 15, 2002. AIRCRAFT INFORMATION The accident airplane was manufactured in 1975 by the Commander Aircraft Division of Rockwell International. It was purchased by the pilot in 1990 and was equipped with its original engine, which was overhauled in July 2003. According to FAA records, as of September 25, 2003, the airplane had accrued 1,224.8 total hours of operation. METEOROLOGICAL INFORMATION A weather observation taken at TJSJ about 4 minutes before the accident, included; wind at 090 degrees at 6 knots, visibility 10 statute miles, scattered clouds at 3,400 feet, broken clouds at 5,500 feet, temperature 23 degrees Celsius (C), dew point 23 degrees C, and an altimeter setting of 30.11 inches of mercury. A weather observation taken at TISX about 6 minutes before the accident, included; wind at 080 degrees at 13 knots, visibility 10 statute miles, scattered clouds at 2,400 feet, scattered clouds at 2,900 feet, temperature 25 degrees Celsius (C), dew point 21 degrees C, and an altimeter setting of 30.10 inches of mercury. According to the United States Naval Observatory sunset occurred at 1825, and the end of civil twilight occurred at 1847. Moonrise did not occur until 0337 on the following day. WRECKAGE AND IMPACT INFORMATION The airplane came to rest in a mangrove thicket, which would experience periodic flooding with brackish water from an adjacent salt marsh. The wreckage path was 76 feet long and oriented on a magnetic heading of 220 degrees. Multiple small portions of burned mangrove and mesquite deadfall was evident, consistent with a postcrash flash fire. The initial impact point was a tree strike located on a mangrove tree 56 feet northeast of the main wreckage. Buoyant objects from the wreckage were spread beneath the root structures of the mangroves throughout the accident site. Examination of the main wreckage revealed no evidence of any preimpact malfunctions of the structure, or engine. The forward fuselage, wing structure, and nose section displayed heavy crush, fragmentation, and compression damage. A 3-foot deep crater corresponded to the point of initial ground contact. The engine was separated from its mounts and was partially buried in the crater. The main wreckage was inverted, with the remains of nose section pointed toward the initial tree strike and the aft fuselage pointed in the direction of travel. Examination of the remains of the aft fuselage and empennage revealed that the empennage was almost completely separated from the aft fuselage and its rudder panel was completely separated from its mounts. The remains of the wings were on their respective sides of the wreckage path and multiple pieces of the primary and secondary control surfaces were spread throughout the trees. All three landing gear were separated from their mounting locations and all doors exhibited evidence of being closed and latched. No preimpact failures or malfunctions of the primary or secondary flight controls were identified. Examination of the flight control system revealed impact damage and multiple breaks in the cables that made up the system. The breaks in the flight control system were consistent with tensile overload, and control continuity was confirmed from the ailerons, elevators, and rudder to the cockpit area. Continuity could not be established to the control yokes or rudder pedals due to fragmentation and crush damage. The wing flaps were found to have been in the up (0-degree) position. Examination of the remains of the cockpit revealed that the cockpit had been fragmented, with evidence that the engine and firewall had been displaced into the cockpit seating area prior to the engine separating from its mounts. The seat assemblies were discovered underneath the main wreckage. The pilot's seat belt and shoulder harness were latched and the webbing was separ ## Aircraft - Registration: [N1261J](https://openairdocs.org/deregistered/N1261J-2011-07-22), registration cancelled 2011-07-22, S/N 261, built 1975 (OpenAirDocs) - Reported make and model: Aero Commander 112 - Registry model: [Aero Commander 112](https://openairdocs.org/model/aero-commander-112) (registry code 0144701) (OpenAirDocs) - Registry engine: [Lycoming I0360 series](https://openairdocs.org/engine/lycoming-i0360-series) (registry code 41515, reciprocating) (OpenAirDocs) - Category: Airplane - Serial number: 261 - Airframe hours: 1224.8 - Engines: Lycoming IO-360-C1D6 200 horsepower reciprocating - Damage: Substantial damage - Fire: On-Ground - Flight: Personal, Part 91 - Airworthiness certificate: Standard, Normal - Last inspection: Annual, September 1, 2003 - Departed: TJSJ, San Juan, PR - Destination: TISX, Christiansted - Flight plan: VFR ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 59; injuries: fatal; private; airplane ratings: single-engine land; medical: class 1, without waivers/limitations; seat: left; flight hours: 900 total ## Weather - Conditions: Visual (VMC), Night - Wind: 90° at 6 knots - Visibility: 10 statute miles - Lowest ceiling: 5,500 ft broken - Temperature: 73 °F, dew point 73 °F - Altimeter: 30.11 inHg - Observed at: TJSJ, 40 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 20040215013679A](https://openairdocs.org/incident/20040215013679A), Feb 15, 2004: Gulstm 112, San Juan, PR, Destroyed, 1 fatal. (-23) The mentioned aircraft N1261J departed from San Juan (tjsj) to st. croix (tisx) at approximated 2030Z 02/15/04. The pilot Mr. Prudoff sheldon, according… 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.