Hydrogen ballon damaged by landing

A Worner 1000 STU gas balloon, of German registry D-OAGH, piloted by a commercial pilot was substantially damaged during landing, when the hydrogen-filled envelope came in contact with a power line, caught fire, and burned.

The balloon was a participant in a racing event associated with an annual festival and was being operated under the provisions of 14 CFR Part 91 without a flight plan. The pilot and copilot reported no injuries.

The balloon had departed the day before the incident. The pilot said they were flying at 3,000 feet (915 m), when they experienced a microburst or something like it. They suddenly found themselves heading for the ground at a very high rate of descent. They dropped ballast to try and slow their descent, but the angle of descent was going to take the balloon into power lines along a road. They then opened the vent and were able to put the basket on the road, but the envelope went into the power lines, tore open, caught fire, and burned.

According to pilot's report, the INITIATING CAUSE was a 'microburst', a leak through the balloon envelope which released hydrogen.
CONTRIBUTING FACTORS where (a) pilot's inadvertent flight into adverse weather conditions during cruise, (b) the unsuitable landing area encountered during the uncontrolled descent, (c) high wind, (d) pilot's unsuccessful attempt to compensate for the wind conditions, and finally (e) pilot's unsuccessful attempt to avoid the power lines during the landing.

gas balloon

The balloon pilot was provided a detailed weather briefing prior to the flight which called for light and variable winds. Soon after departure, the winds increased from 4-6 knots to 6-8 knots, gusting to 15 knots. The pilot flew around waiting for winds to subside to no avail. The pilot was forced to land with the prevailing high winds when he started getting low on fuel.

The pilot and co-pilot reported no injuries.
The basket and support cables sustained no damage and are serviceable, while the envelope sustained substantial damage from the fire.

None

Transport balloons are characterised by hazards related to the difficulty to manoeuvre and manage the flight. Loss of gas providing buoyancy is an additional hazard.
if hydrogen is used as buoyancy gas, additional hazards could come from its flammability.
However, in this case hydrogen was not at the origin of the event. Its burning when in contact with the power line did not add risk to the flight, because the crew succeeded to bring the basket safe to the ground. The fire caused only material damage.

Transport balloons are characterised by hazards related to the difficulty to manoeuvre and manage the flight. Loss of gas providing buoyancy is an additional hazard.
if hydrogen is used as buoyancy gas, additional hazards could come from its flammability.
However, in this case hydrogen was not at the origin of the event. Its burning when in contact with the power line did not add risk to the flight, because the crew succeeded to bring the basket safe to the ground. The fire caused only material damage.
The guidelines issued by the balloon manufacturer cover the case of contact with power lines: power lines:
“If a hydrogen-filled balloon envelope contacts an overhead power line, this can lead to a fire or explosion. If the suspension ropes touch the overhead power line, there is the additional risk of the basket being separated from the envelope and falling to the ground. If there is a risk of contact with an overhead power line, it is imperative to perform an emergency landing before the overhead power line. The basket should be brought as close to the ground as possible before contact. The following procedure must be observed in this case:
(1) Pull the parachute to initiate a faster descent of the balloon. Accept the possibility of a hard landing.
(2) Emergency call: If possible, place an emergency call to have the power line switched off.
(3) Passengers: The power line must not be touched!
(4) If the basket remains suspended just above the ground, there must be no contact between the basket and the ground before the power has been cut off. Passengers must not exit the basket, nor may helpers touch the basket directly or indirectly (e. g. using a pole, ladder or other item.)”

In this event, the basket touched the ground, and at the same time the envelope touched the power line. Nevertheless, the two pilots were not affected by the possible voltage discharge between the power lines and the ground.