N7059U

HISTORY OF FLIGHT

On June 8, 2013 at 0815 mountain daylight time, an Aerostar International Incorporated RX-8 hot air balloon, N7059U, impacted terrain and dragged across a road during a high wind landing near Arvada, Colorado. The airline transport rated pilot was seriously injured and the two passengers on board were not injured. The balloon sustained substantial damage to the envelope and basket. The balloon was registered to and operated by the pilot under the provisions of 14 Code of Federal Regulations Part 91 as a personal flight. Visual meteorological conditions prevailed for the flight, which operated without a flight plan. The flight originated from Gunbarrel, Colorado, about 0705.

The pilot stated that he and a number of other balloon pilots gathered at the launch site about 0530 to discuss weather information obtained from the internet and various other sources. The pilots agreed that the forecast weather provided suitable conditions for a safe flight that morning. The weather conditions at the time of their discussion, however, caused them to delay their launch. They were experiencing light and erratic winds at ground level and after putting up some pibals (small helium-filled balloon used to determine wind speed and direction), saw that the wind conditions would take them in an undesirable direction at an undesirable speed. The pilot said that these conditions were quite typical for flying in the area at the early hours of the day. The pilot said they continued monitoring the current and forecast weather using their wireless devices to monitor the internet sites. At 0615, the wind at the launch site calmed and additional pibals put up showed the wind at altitude would take the balloons to the east-southeast, and then south at about 3 to 5 miles per hour. The pilots decided that they would fly as long as there was no further increase in wind speed during the launch. The pilot said the passengers got into the balloon, he gave them a safety briefing, and they took off at 0705. At takeoff the wind was calm to about 3 miles per hour. They traveled to the east-southeast and then at about 1,000 to 1,200 feet agl made a turn toward the south. The pilot said that the first 30 to 40 minutes of flight were smooth and the balloon traveled slowly to the southeast. At about 0740, the pilot said he experienced a wind gust that buffeted the balloon. He was at an altitude of 6,200 feet msl. He said he reported the condition to the other pilots who were flying in the area, and received reports back that they were experiencing similar conditions at various altitudes. As he looked at the other balloons, the pilot noticed significant distortions in the envelopes (indicative of high winds). The pilot said he prepared his passengers for a high wind landing. He selected a landing site that he described as a construction area cleared of machinery and survey stakes. As he touched down, he pulled the deflation lines to deflate the balloon. The balloon deflated in seconds but the envelope concaved in a "spinnaker sail configuration" and dragged the balloon for several hundred feet until coming to rest on the side of a highway. He told the passengers to exit the basket and asked them if they had been injured. They told him they were okay. The pilot, however, sustained serious rib injuries. The balloon's envelope sustained torn fabric from contact with the ground and obstructions on the ground. The balloon basket was also heavily damaged during the impact and from being dragged.

PERSONNEL INFORMATION

The 69 year old pilot held an airline transport pilot certificate with ratings in single and multiengine instrument airplanes and in a free balloon. The pilot completed a flight review on September 19, 2012 and reported having 495 hours as pilot-in-command in the Aerostar RX-8. According to the FARs balloon pilots do not have to possess a medical certificate.

AIRCRAFT INFORMATION

The aircraft was a free balloon with airborne heater. It was being operated in the normal category. At the time of its last annual inspection on April 23, 2013, the balloon envelope had 495.2 total hours of flight time.

METEROROLOGICAL INFORMATION

The National Weather Service (NWS) Surface Analysis Chart at 0600 MDT depicted a low pressure system over North Dakota with an associated occluded front al system extending from the low south-southeast to another low pressure system over South Dakota where the triple point of the front was located. There it split into a warn front to the southeast and a cold front to the southwest across Nebraska and northern Colorado, and then west-northwest back into Wyoming. Two high pressure systems were located over western Colorado and two low pressure systems were located over eastern Colorado with a trough of low pressure extending between the lows into New Mexico. The resultant pressure systems created a light westerly wind component over the region with wind speeds of 10 knots or less, with the cold front oriented in an east-to-west direction over northern Colorado south of the cold front.

The station model for Denver International Airport depicted a wind from the west-southwest at approximately 10 knots. The station model for Cheyenne, Wyoming, 78 miles north of Denver depicted a northerly wind sustained at approximately 25 knots. Several stations over Wyoming and Nebraska behind the cold front depicted northerly winds at 15 to 20 knots.

At 0900, the low pressure system over South Dakota became the primary system with the cold front extending south-southwestward across Nebraska and into central Colorado. The station model for Denver depicted a wind from the north at 15 knots. Several other stations in northeast Colorado depicted northerly winds sustained at 15 to 35 knots, with stations south of the front reporting westerly winds at 10 knots or less.

At 0655, the routine aviation weather report (METAR) for the Erie Airport (KEIK), 13 miles northeast of the accident site, was wind 300 degrees at 4 knots, clear skies, visibility 10 miles, temperature 68 degrees Fahrenheit (F), dew point 43 degrees F, and altimeter 29.81 inches.

At 0755, KEIK METAR reported wind 030 degrees at 16 knots, gusts to 24 knots, clear skies, visibility 10 miles, temperature 65 degrees F, dew point, 47 degrees F, and altimeter 29.89 inches.

The first weather observation for the area that indicated a frontal passage was at Cheyenne Regional Airport, Wyoming. At 0453, automated wind was reported as 270 degrees at 9 knots. At 0549 the automated wind was from 350 degrees at 23 knots gusting to 38 knots.

Wind conditions at Fort Collins-Loveland Municipal Airport, 38 miles north of Denver, at 0635 were calm. At 0655 when the front passed through, the wind was 020 degrees at 13 knots gusting to 25 knots. By 0815, the wind was gusting to 35 knots.

The front moved through Denver International Airport at 0744, when a squall or sudden increase in wind speed was reported from 020 degrees at 24 knots gusting to 34 knots. Wind gusts would continue for the next few hours with gusts of 36 knots reported at 0753 and gusts of 24 knots at 0853.

The front continues to south reaching Front Range Airport, 19 miles east of Denver, at 0755 and Centennial Airport, 15 miles southeast of Denver, at 0834 and producing gusts to 30 and 35 knots respectively.

The Denver upper air sounding or rawinsonde observation at 0800 depicted a surface-based temperature inversion due to radiational cooling from the surface to approximately 500 feet agl with light winds below and winds from the west immediately above the inversion through 10,000 feet and veering to the northwest with wind speeds increasing with height. A low-level wind maximum was identified at 7,000 feet from 270 degrees at 30 knots. A mean 18,000 feet wind was from 308 degrees at 31 knots, and the level of maximum wind at 35,000 feet was from 330 degrees at 80 knots. The sounding depicted a stable atmosphere with a Lifted Index of 5. The lifted condensation level wat identified at 5,055 feet agl with a convective condensation level at 12,226 feet agl. The equilibrium level or expected top of convective clouds was at 37,000 feet. The freezing level was identified at approximately 14,801 feet.

The sounding wind and temperature profile supported mountain wave conditions with waves at 12,000, 15,000, and 19,000 feet.

The NWS Terminal Aerodrome Forecast (TAF) was issued by the Denver/Boulder Weather Service Forecast Office located in Boulder, Colorado. The TAF for Denver International Airport during the period in which the accident took place were as follows:

Denver Terminal Area Forecast, July 8, 2013 at 1139 UTC (0539 MDT,) wind 210 degrees at 13 knots, visibility more than 6 statute miles, few clouds at 8,000 feet mean sea level (MSL), scattered clouds at 12,000 feet MSL

From 0800, wind 310 degrees at 11 knots, visibility more than 6 statute miles, few clouds at 8,000 feet MSL

From 1000, wind 020 degrees at 13 knots, gusts to 23 knots, visibility more than 6 statute miles, few clouds at 8,000 feet MSL

From 1700, wind 060 degrees at 13 knots, visibility more than 6 statute miles, few clouds at 8,000 feet MSL, broken ceiling at 15,000 feet MSL

From 2000, wind 140 degrees at 5 knots, visibility more than 6 statute miles, few clouds at 8,000 feet MSL

From 0000 on June 9, 2013, wind 200 degrees at 7 knots, visibility more than 6 statute miles, few clouds at 10,000 feet MSL

From 0700 on June 9, 2013, wind 270 degrees at 5 knots, visibility more than 6 statute miles, few clouds at 10,000 feet MSL

An amended TAF was issued for KDEN at 0652, with forecast wind 210 degrees at 13 knots, visibility more than 6 statute miles, few clouds at 8,000 feet MSL, scattered clouds at 12,000 feet MSL, and scattered clouds at 22,000 feet MSL

From 0830, wind 010 degrees at 18 knots, gusts to 30 knots, visibility more than 6 statute miles, scattered clouds at 8,000 feet MSL, scattered clouds at 12...