HISTORY OF FLIGHT On November 16, 2007, at 0915 central standard time, an experimental Padelt PG37-1 helium filled balloon collided with power lines in Hampton, Iowa. The commercial pilot and one pilot-rated passenger were fatally injured. A second passenger received serious injuries. The balloon received substantial damage. The Title 14 Code of Federal Regulations Part 91 personal flight originated from Greeley, Colorado, at 2330 mountain standard time, on November 14, 2007. Visual meteorological conditions prevailed at the time of the accident. The surviving passenger stated they departed Greeley with the intention of flying one or two nights depending on the weather and how they were feeling. He stated they flew through Wednesday night [the night of November 14th] and there were no problems with the balloon. He stated they switched off during the night with two people staying awake while the third person slept. He stated that on Thursday afternoon [November 15th] the pilot asked if they wanted to continue another night or if they wanted to land. He stated they were all feeling good so they decided to continue the flight. The passenger stated that prior to the accident they stowed the gear in the gondola and prepared for a morning landing. He stated they began a three to four mile "stair-step" approach for landing. The approach consisted of repeatedly dropping ballast, venting, and leveling off. He stated the approach was well controlled and they were not in a hurry to land. The passenger stated that the pilot told him to man the ballast box and instructed him to open some of the ballast bags in case they needed to dump ballast quickly. The passenger stated they saw the power lines during the approach and the pilot asked him to drop a half of scoop, about two cups, of sand. Shortly thereafter, the pilot asked him to drop another half of a scoop, which he did. The pilot then instructed him to drop half of a bag of sand. He stated they thought the balloon was going to clear the power lines. When it became evident that they were going to contact the lines, the pilot instructed both passengers to get into the bottom of the gondola. The passenger recalled the side of the gondola hitting the top cable of the power lines and hearing screeching or arcing sounds, but he did not see any sparks. The balloon tipped on its side a couple of times and they were thrown around inside the gondola. He remembered seeing the power lines wedged between the balloon cables and the top of the gondola. He stated the balloon remained entangled in the power lines for several minutes. He then heard a snap and the gondola fell to the ground. The passenger stated they saw the power lines three to five minutes prior to contacting them. The balloon contacted the top line in a string of four power lines. The altitude of the line that was contacted was approximately 60 feet above the ground. The gondola came to rest approximately 20 feet from the lines. The envelope continued on and was located in a field approximately three-quarters of a mile away from the accident site. PERSONNEL INFORMATION The pilot, age 62, held a commercial pilot certificate with a lighter-than-air balloon rating. The pilot had approximately 738 hours of balloon flight time of which 254 hours were in helium balloons. The pilot completed his last biennial flight review in May 28, 2007. The passenger who was fatally injured held a commercial pilot balloon certificate that was limited to hot air balloons. The surviving passenger held a private pilot balloon certificate that was limited to hot air balloons. METEOROLOGICAL INFORMATION Weather conditions reported at Fort Dodge Regional Airport, Fort Dodge, Iowa, located approximately 43 miles west-southwest of the accident site, at 0915 were: Wind from 220 degrees at 12 knots gusting to 19 knots; visibility 10 statute miles; sky condition clear; temperature 6 degrees Celsius; dew point minus 5 degrees Celsius; altimeter 29.97 inches of mercury. MEDICAL AND PATHOLOGICAL INFORMATION An autopsy of the pilot was performed on November 17, 2007, at the Iowa Office of the State Medical Examiner in Ankeny, Iowa. The final autopsy report listed the cause of death as "Blunt force injuries of the chest." An autopsy of the pilot-rated passenger was performed on November 17, 2007, at the Iowa Office of the State Medical Examiner in Ankeny, Iowa. The final autopsy report listed the cause of death as "Positional asphyxia with cervical neck fracture." A Forensic Toxicology Fatal Accident Report was prepared for the pilot by the FAA Civil Aeromedical Institute, Oklahoma City, Oklahoma. The test results indicate that Pseudoephedrine was detected in urine. A Forensic Toxicology Fatal Accident Report was prepared for the pilot-rated passenger by the FAA Civil Aeromedical Institute, Oklahoma City, Oklahoma. The test results indicate: 0.361 (ug/ml, ug/g) Citalopram detected in blood Citalopram present in urine 0.235 (ug/mL, ug/g) N-Desmethylcitalopram detected in blood N-Desmethylcitalopram present in urine DI-N-Desmethylcitalopram NOT detected in blood DI-N-Desmethylcitalopram present in urine