DCA10LA083

The rapid climb and descent of FAST13 within 30 seconds exceeded the radar systems capability to accurately track and display the altitude changes. Accordingly, the air traffic controller providing services to TCF7530 and FAST13 did not observe FAST13 climb above the assigned altitude of FL280 nor did the controller receive a conflict alert from the radar system. The reason for FAST 13's deviation from assigned altitude was not determined. The TCAS onboard TCF7630 alerted as expected and the first officer appropriately initiated a climb in response to the RA. The seat belt sign was on prior to the TCAS alert because the flight attendants were preparing the cabin for landing. Shortly before the event, a passenger elected to go to the lavatory even though a flight attendant advised the passenger to return to his seat. The passenger was in the lavatory when the TCAS RA occurred resulting in him receiving a serious injury.

On August 9, 2010, about 1134 central daylight time, Shuttle America flight # 7630 (TCF7630), an Embraer 170, N856RW, responded to a Traffic Alert and Collision Avoidance System (TCAS) resolution advisory while in cruise flight at flight level (FL) 290 resulting in an abrupt maneuver. Of the 74 passengers and crew onboard, one passenger received serious injuries. The flight was operating under the provisions of 14 Code of Federal Regulations Part 121 as a scheduled passenger flight from Chicago O'Hare International Airport (KORD), Chicago, Illinois, to Louis Armstrong New Orleans International Airport (KMSY), New Orleans, Louisiana. Around the time of the event, U.S. Air Force Northrop Corporation T-38 Talon, call sign FAST13, was on a cross country military training flight in cruise flight at FL280. FAST13 was operating under the provisions of 14 Code of Federal Regulations Part 91 from Campbell Army Airfield (KHOP), Fort Campbell/Hopkinsville, Kentucky, to Chennault International Airport (KCWF), Lake Charles, Louisiana. There were two crewmembers aboard and the airplane was not equipped with a TCAS. A review of radar data indicates that, at 1134:17, Shuttle America flight # 7630 (TCF7630) was southbound in cruise flight at FL290 and FAST13 was southwest bound at FL280. The aircraft were on a converging course. Raw radar data indicates that at 1134:27 FAST 13 began a brief climb to FL286 before returning to FL280 at 1134:57. During FAST13's ascent to FL286, TCF7630 received a Traffic Alert and Collision Avoidance System (TCAS) warning resolution advisory (RA), directing the pilot to climb. The TCF7630 first officer, who was the flying pilot, immediately climbed to FL296 before returning to the previously assigned altitude of FL290 when the flight crew visually identified the T-38 and the conflict was clear. TCF7630 informed air traffic control of the TCAS RA and that the flight had to climb to avoid oncoming traffic. During the abrupt TCAS maneuver, a passenger in the aft lavatory of TCF7630, suffered a compound fracture of his leg. The flight attendants and two medical doctors who were onboard provided basic first aid to the injured passenger until TCF7630 landed at KMSY where medical personnel met the aircraft and transported the injured patient to the hospital. Review of the air traffic control radar data revealed that the altitude change by FAST13 was not displayed on the ATC radar nor observed by the air traffic controller.