On August 14, 2011, at 1126 mountain daylight time, N53473, a Boeing A75N1(PT17), sustained substantial damage when it collided with terrain shortly after takeoff from Fabens Airport (E35), Fabens, Texas. The private pilot and the pilot rated passenger sustained serious injuries. The airplane was registered to a private individual and was operated by the pilot. Visual meteorological conditions prevailed and no flight plan was filed for the personal flight conducted under 14 Code of Federal Regulations Part 91. The cross-country flight was originating at the time of the accident and was en route to Santa Teresa, New Mexico. The pilot said that airplane had just undergone maintenance to repair the magnetos. On the day before the flight, he performed a test run of the engine and cycled each magneto. The pilot said the engine and both magnetos tested fine. On the day of the accident, the pilot performed another engine run and again there were no anomalies with the engine or the magnetos. After the last engine run, the pilot and his passenger departed for another airport. The pilot said the engine did not have enough power (about 100 to 200 RPM less than expected) but could not recall the RPM setting. He continued with the takeoff and during the climb he was unable to maintain a safe airspeed. When the airplane was less than 100 feet above the ground, he elected to turn back to the airport. At that time, he recalled the airspeed was between 40-50 (he did not recall if that was knots or miles per hour). While in the turn he said the airspeed decreased to 40, the left wing stalled, and the airplane nosed over toward the ground. The pilot tried to level the wings prior to hitting the ground and did not remember the impact. In a written statement, the pilot rated passenger said the airplane did not seem to accelerate very well on the take off roll and the climb rate was marginal. He said that when the airplane was approximately 100 feet above the ground, the pilot entered a left turn at which time the airspeed indicator read 52 to 55 (he was not sure if it was knots or miles per hour). While in the turn, the airplane suddenly stalled and the left wing dropped. It descended at a steep angle but the pilot was able to level the wings before impact. Several Federal Aviation Administration (FAA) inspectors performed an on-scene examination of the airplane. According to one of the inspectors, the airplane sustained damage to the firewall, fuselage and the wing struts. The inspectors were unable to determine the reason for the loss of engine power. Weather reported at El Paso International (ELP), El Paso, Texas, about 21 miles Northwest of the accident, at 1151, was reported as wind from 280 degrees at 9 knots, visibility 10 miles, few clouds 5,500 feet, scattered clouds 25,000 feet, temperature 31 degrees Celsius, dewpoint 15 degrees Celsius, and an altimeter setting of 30.03 inches of Mercury. Calculation of relevant meteorological data revealed that the density altitude was 6,425 feet. A review of the carburetor icing probability chart, located in the FAA's Special Airworthiness Information Bulletin CE-09-35, dated 6/30/2009, revealed that the airplane was operating in an area favorable for the formation of carburetor icing at glide and cruise power.