When can hot air balloons fly? Meet the man who decides if Bristol Balloon Fiesta mass ascents go up
The mass ascents are one of the most popular parts of Bristol International Balloon Fiesta - but there is always an air of jeapordy around them.
Dozens of hot air balloons are scheduled to take off at the same time twice a day during the festival, at 6am and 6pm. But hot air balloons need very specific weather conditions to fly.
The first mass ascent of the 2024 fiesta had to be cancelled due to windy conditions, but organisers say "much calmer winds" are on their way which looks promising for later ascents.
Pete Dalby is the chairman of the fiesta’s flying committee. The committee is in charge of deciding whether the balloons go up for the mass ascents.
It was Pete who made the final decision that this morning's ascent could not happen.
"It might have seemed okay," he told ITV News. "But we had 10-12 knots of wind with gusts to about 25 knots."
Pete said that while conditions can seem perfect on the ground, there is a lot to consider when deciding if balloons can fly.
“It’s not always just the wind," he said. "Obviously if it’s windy then we can’t fly because it’s dangerous but there’s other reasons why we can’t fly.
“If the wind is in the wrong direction - if it’s going out towards Bristol Airport, or towards the Bristol Channel.
"If there’s any potential rain about we don’t fly, because if you get hit by a rain shower that’s not very good for the balloon.
“And also if the visibility is poor or if the cloud base is too low - because if we’re going to fly over the city, we’ve got to be a certain height over the city and if that means going into cloud that makes it an illegal flight.”
Weather does not just impact balloons taking flight, it can also impact tethering at the fiesta.
Watch as pilots brave windy conditions and try in vain to inflate balloons
Pete said: “When you get a gust of wind behind these big balloons with three to four tonnes of hot air in them they pull vehicles all across the launch field and cause all sorts of problems.”
Sunday 11 August currently looks particularly hot, with temperature highs of 27C. Pete said this shouldn’t be a problem though.
“We had problems a couple of years ago when it was mid-30s so the atmosphere was very unstable, it’s not going to get like that this year though.
“We’re going to get a couple of nice days which will be very balloon-friendly, as far as I’m aware."
The impact of the weather does not end at the point of take off, though. Once balloons are up in the air, pilots need to keep an eye on conditions to private crashing into each other.
“We can talk to each other whilst we’re in the air," Pete said.
“We make sure when we’re flying among other balloons we don’t make fast climbs because that is the danger if you’ve got two balloons coming up against each other.
“If they bump into each other side-by-side that’s fine, but climbing is something we need to look out for which is why we need to be careful if the weather is unstable.
“You can get lifted by a thermal wave and then you’re climbing without the pilot doing anything.”
Pete not only decides on the mass ascents going ahead, but he is also one of the pilots going up.
He started off as a private pilot 38 years ago and has been running his own business for 30 years.
He said: “Being here in Bristol, I got attracted to the fiesta, started helping out, and then worked my way up the committee side of things.”
Despite years of ballooning, Pete said “the novelty never wears off”.
“When you’re flying and the crowds are full and you take off and get all the cheers from the crowds, it’s just amazing.
“People should get down here because it’s a great event, lots of activity, it’s entertaining, meet the teams, it’s great.”