Accident Overview
On December 3, 2008, at about 1205 Atlantic standard time, a Rockwell International 690B, registration N318WA, operated by Websta's Aviation Services Inc., was destroyed when it impacted terrain while maneuvering approximately 4 nautical miles southeast of Rio Grande, Puerto Rico. The pilot and two passengers were killed. Day instrument meteorological conditions prevailed at the accident site. No flight plan had been filed. The flight departed Beef Island International Airport (TUPJ), Tortola, British Virgin Islands, and was destined for Luis Munoz Marin International Airport (TJSJ), San Juan, Puerto Rico. The commercial operation was conducted under 14 CFR Part 135.
Aircraft Information
The accident aircraft was a high-wing, pressurized, twin-engine airplane configured for eight passengers. It was powered by two Garrett TPE331-5-252K turboprop engines, each producing 776 shaft horsepower. The airplane was equipped with an L-3 Communications Landmark TAWS 8100 Terrain Avoidance Warning System, installed in March 2005. Post-accident examination of the TAWS unit revealed heavy crush and fire damage, and no information could be extracted; it could not be determined if the unit was functional before the accident. The airplane was manufactured in 1977 and had previously been registered as D-IFAC, N1KC, and N690TG before being registered as N318WA in October 2003. Maintenance logbook entries after that date were vague, and it was not possible to verify completion of all required maintenance, including service bulletins and airworthiness directives. Some phase inspections were conducted in accordance with "Rainbow International Airlines procedures." Daily flight log sheets found at the accident site indicated that the operator was Rainbow International Airlines. The logs showed that in the 2.5 years prior to the accident, the airplane had accrued approximately 50 flight hours, and as of March 27, 2008, the total hours were 5,286. Engine time and cycles recorded referred to a 1997 overhaul, not since new. Sixteen of twenty flight log sheets contained engine trend data, but all entries had identical parameters and lacked non-engine data such as airspeed, altitude, and outside air temperature.
Meteorological Conditions
The reported weather at TJSJ, about 14 miles northwest of the accident site, at 1156 included wind 070 at 11 knots, visibility 10 miles, few clouds at 3,000 feet, scattered clouds at 7,000 feet, temperature 28°C, dew point 18°C, altimeter 30.00 inHg, and showers to the distant southeast. Witnesses reported fog and rain near the accident site, with mountains obscured. According to the US Forest Service, low clouds and fog are typical in El Yunque National Forest, which receives up to 240 inches of precipitation annually.
Wreckage and Impact
Examination revealed that the main wreckage came to rest perpendicular to a cliff face at an elevation of 2,310 feet, with no wreckage path. The wreckage displayed heavy crush and fragmentation, and a post-crash fire had occurred. Sooting was found on the cliff face in a vertical direction. Fragments of wing structure, nose section, cockpit, flight controls, fuselage, and engine gearboxes were against the cliff. Fragmented structure, system components, propeller components, and both engine power sections were discovered about 200 feet below the cliff on a 50-degree slope. A palm tree near the cliff base showed damage consistent with a propeller strike; broken limbs and branches throughout the site exhibited multiple cuts consistent with propeller strikes. The landing gear was found in the up position. Control continuity could not be established, but no preimpact flight control or structural failure was found. Both engines were missing their accessory gearboxes. The left engine's front (including gearbox forward of the first stage compressor impeller) was missing; the impeller blades were bent opposite rotation. The right engine's aft end showed heavy compression damage; the third stage turbine rotor had missing and bent blades, and the second stage impeller blades were also bent opposite rotation. One propeller hub had a single blade attached; the other hub also had one blade. All discovered blades exhibited leading edge gouging, polishing, chordwise scratching, twisting, curling, and S-bending.
Air Traffic Services
N318WA was receiving VFR radar traffic advisory services from San Juan Center Approach Control Facility (CERAP). The pilot first contacted San Juan at 1548:23, reporting over Beef Island en route to San Juan. The controller assigned a transponder code and radar identified the aircraft 11 miles northeast of St. Thomas. At 1554:06, the pilot reported climbing to 8,800 feet. The aircraft was transferred to another controller, and at 1600:18 reported descending through 8,000 feet. The controller instructed heading 270, maintain VFR at or above 2,500 feet, and enter right downwind for runway 10. At 1603:00, the altitude restriction was deleted. At 1604:10, the controller asked for altitude after noticing the readout changed to "XXX"; the pilot replied descending through 3,200 feet. The controller asked the pilot to confirm VFR conditions and advised the minimum vectoring altitude (MVA) was 5,500 feet. The pilot replied unintelligibly, then stated "we are in and out of some clouds right now." The controller advised to maintain VFR and repeated the MVA. Multiple attempts to contact the pilot were unsuccessful. Radar data showed the last target at 1604:41 indicating 2,400 feet, located east of the impact point. The Aeronautical Information Manual (AIM) paragraphs regarding radar assistance to VFR aircraft and pilot responsibilities were referenced in the investigation.
Medical and Pathological Information
A postmortem examination was performed on the pilot by the Puerto Rico Institute of Forensic Sciences. Toxicological testing was conducted at the FAA Bioaeronautical Sciences Research Laboratory.
Operator and Regulatory Information
Rainbow International Airlines Inc. held a Part 135 certificate and permission to operate commercial flights to UK Overseas Territories. On December 5, 2008, its Director of Operations advised the FAA that the accident flight was not associated with Rainbow International and that Websta's Aviation Services Inc. was not given permission to operate under Rainbow's permit. On September 29, 2010, the DO stated that the pilot and accident airplane had been on Rainbow's certificate but the pilot separated after obtaining his own Part 135 certificate. Websta's Aviation Services Inc. received its Part 135 certificate on January 19, 2006, and operated a fixed base operation at Henry E. Rohlsen Airport (TISX), St. Croix. However, Websta's did not hold permission to operate commercial flights to UK Overseas Territories. Review of General Declaration forms found in the wreckage showed the pilot listed the operator as Rainbow International Airlines Inc. for flights to and from TUPJ. Tracking data from US Immigration and Customs Enforcement revealed that Websta's had operated into TUPJ on 7 other occasions since January 2006, as well as into Antigua (9 times) and Anguilla (at least 60 times).