A dedicated team of students from Reigate Grammar School weather station successfully launched a high altitude balloon (HAB) and retrieved the payload on Tuesday 25 November 2014. After months of meticulous planning and with close cooperation and assistance from the scientists at the Met Office, Met Research Unit, Cardington Boundary Layer Research Facility and in collaboration with Chris Hillcox Near Space Photography, our students launched the 800g balloon and then used GPS trackers to chase and locate the payload as it fell to earth after an extraordinary 3.5 hour flight collecting some of the best amateur high altitude balloon photos of near space. The students and staff were delighted by the success of their mission which took careful planning and preparation to reduce the risk of failure, which always remained a possibility. The balloon took 2 hours to ascend 100,000 feet (30km) into the stratosphere, through temperatures as low as -70C in the tropopause, before the balloon burst at pressures 100x lower than at the surface. The descent took over an hour. Videos of the story can be found below. See below also for “Why did we do this?”
Planning
Students spent weeks prior to the launch designing and building a lightweight box (150g) that would carry the payload safely to an incredible altitude up to 30km into the atmosphere. The payload consisted of several HD cameras, spot GPS trackers and a GSM locator with meteorology sensors which were weighed to ensure the balloon would be able to lift them to the target burst height at 30km (100,000 feet) with 3.5m cu of helium. All equipment was thoroughly tested (several times). GPS trackers were tested to ensure phones would pick up the track reliably. A laptop was enabled to operate on a mobile connection. GoPro cameras were tested and checked, as were HTC cameras. A school logo was laser cut onto a small plastic arm that would sit in front of one of the cameras during the ascent. CAA approval was applied for and received. Scientists at the Met Office research unit were also closely consulted regarding gas type (99.5% helium, not party grade!) and the practicalities of the launch location such as trees and masts. Risk-benefit assessments based on MetOffice launch assessments were completed and approved. Various risks needed to be considered beyond allergies to latex and the dangers of helium inhalation, particularly regarding student involvement in retrieval that might require travel across land that lacked nearby public access. We checked and adjusted school insurance to ensure full coverage for the flight. However, in the end, it was the good will and enthusiasm shown by the individuals involved with the student launch that drew the threads together and allowed us to proceed with this unique educational challenge. Acknowledgements are listed below.
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- early stages
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- measuring up the HAB
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- cut outs to house kit
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- laser cutting the logo
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- more cutting
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- design finished
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- adding contacts to ensure return
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- adjustments before flight
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- taping up to secure items
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- HTC and spot trackers
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- kit installed
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- final briefing
Predicting the right weather
To avoid the balloon payload shooting off across the North Sea we had to choose a day when the jetstream and higher altitude winds in the stratosphere were relatively slack. Winds in different directions with height would also be useful to ensure the balloon did not travel too far for retrieval purposes. A single date could therefore not be fixed in advance due to changing autumnal weather conditions. Parents of students were sent an open letter with details regarding the potential for this expedition and ways we would contact them to ensure students were available as any possible launch date approached. The weather at all altitudes was studied carefully and a potential launch date emerged for Tuesday 25 November as a weak high pressure pushed the jetstream and high altitude winds further north. A suitably safe landing site was also critical to mission success and the HABHUB website landing predictor was regularly consulted in the run up to the launch. Conditions improved throughout the period until Tuesday looked the most ideal. We were GO FOR LAUNCH!
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- landing site predicted
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- fog early am
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- 1000 hPa surface gusts: none
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- winds 925hPa : 900m
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- winds 850hPa : 1500m
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- winds 700hPa: 3000m
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- 500hPa: 5500m
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- 300hPa 9000m
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- atmosphere cross section
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- jetstream: out the way
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- ideal slack surface high
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- predicted troposphere temps (balloon would go off the chart)
The launch
The launch day started early as the team had to travel well beyond the flight paths of Gatwick and Heathrow. Our launch site was in Bedfordshire with a predicted landing site NE of Cambridge.
Amanda Kerr-Munslow, a Met Office Boundary Layer Research Scientist, gave the group a very interesting tour of the site, including lasers that measured cloud height. Dave Bamber the Met office facilities manager then helped students inflate the balloon. The payload box had last minute modifications completed and was then prepared and carried to the launch bed. The balloon was carefully transferred, inflated, to attach to the payload at the launch site. Cables checked, final preparation and then the countdown! The pictures below show some screenshots captured by the movie cameras on the ascent to 100,000 feet.
short film: (FULL FILM scroll below)
(please refresh the page if video is from another playlist)
Payload retrieval
The chase and retrieval were very exciting! Despite predictive forecasts showing a broadly good landing area (open farmland, flat, few forests, rural, few pylons etc) it was not certain that it would avoid landing in problem locations like hedges or trees, pylons, main roads, rivers, ditches, inaccessible fields remote from a road or someone’s roof! It was an exciting moment for the team when the tracks stopped at Wicken Fen in Cambridgeshire and the maps appeared to show a landing site in an open field which appeared to be accessible from the road. Reflective vests on and trackers in hand we rushed off to search and found the payload with the shredded remains of the burst parachute precisely on target. A wonderfully memorable moment after an exciting and highly rewarding adventurous day for everyone involved.
Why did we do this?
It has been a long-term aim of the RGS weather station to launch a HAB. Reasons are myriad but the experience of this has been a high quality challenging learning and teamwork experience for students and staff. Practical skills, meteorology and an understanding of the atmosphere were all critical for students to grasp to increase the chances of a successful launch and, importantly, retrieval. The students more than rose to the challenge! At RGS the sky is not the limit!
A driving force behind this enterprise has been to raise climate and weather awareness amongst students and more widely. The images and story brought back beautifully illustrate the fragile atmosphere in which we all live and upon which the human race depends. From our balloon view the atmosphere was shown as a thin blue veil of gases held precariously against the surface with the blackness of space directly above and not far away. It is of course widely accepted that humans are forcing climate change which might potentially threaten our existence because we have altered the workings of the delicate atmospheric envelope. The site and sound of planes cruising far below our balloon demonstrated how we might dominate a tiny hospitable part of the planet but that we reside perilously close to utterly hostile environments. In this respect it is no surprise that we have probably damaged this delicate life-protecting atmosphere with our activities. We would like anyone using our pictures to ensure that climate change is explicitly mentioned and that our balloon launch post is linked to any material used.
What next?
This project has proved that the stratosphere is closer than ever and increasingly accessible. School exploration of the stratosphere is now within the budget of schools or groups of schools that can collaborate (rather timely considering recent political announcements). Currently it costs around £200 to launch a payload to 30km, to launch a further 30km above that would cost £200 million (Antares rocket cost)! The exploration and science that schools can do at 30km is breathtaking! Floating balloons are also possible for longer experiments. The IPCC consider that our climate is on the cusp of irretrievable change that will have great impacts in the next 100 years. It is therefore of the utmost importance that schools engage their students with weather and climate and that exam syllabuses include meteorology and climate across a variety of disciplines.
This video of the flight has been edited from 6 hours of footage from 3 cameras pointing in different directions (GoPro Hero3, 2 HTCs) over the course of the 3.5 hour flight. It also includes screenshots and photos showing the story of how students put their payload into near space.
(please refresh the page if video is from another playlist)
11 video questions for classes: (ask “why” / “how” for extension)
- Why is the flight path not straight?
- At what height do clouds stop?
- It rains ice particles from blue sky at some points in the flight. Why might this happen?
- Does all rain that falls out of a cloud reach the ground?
- Are any clouds man-made?
- Listen to the wind and noise picked up by on-board camera mics during the flight: how does it change?
- How does the colour of the sky change with altitude?
- How “near space” actually is 100,000 feet (30km)?
- Which was the coldest part of the ascent?
- As the balloon burst there was a puff of “smoke”, what was this?
- Shreds of burst balloon were seemingly left hanging above the descending payload. What do you think happened to these?
RGS launch team:
- Piers Rex-Murray
- Tom Tatham
- Jasmine Hull
- Louis Chambers
- Edgar Povey
- George Beglan
- Harry Persand
- Chris Meredith
- Fraser Cadman
- Matt Taylor
RGS staff:
- Simon Collins
- Peter Klein
- Vanessa Ramsden
Acknowledgements and sincere thanks to the following:
Huge sincere thanks to the following for helping us to get our HAB project off the ground.
- Near Space Photography : Chris Hillcox Chris was incredibly helpful in giving students ownership of their launch in all stages whilst offering any amount of technical know-how we needed to increase chances of success. Chris gave his time extremely generously throughout the enterprise and his expertise was pivotal in the success of the mission. Many thanks Chris!
- Royal Meteorology Society RMetS : especially Sylvia Knight who encouraged us to pursue the project and put us in touch with Amanda. Thank you Sylvia!
- Met Office, Met Research Unit, Cardington : Boundary Layer Research Facility: David Bamber and Amanda Kerr-Munslow were on the launch site at Cardington. Amanda gave us a thorough tour of the scientific research unit and assisted with all practical aspects of getting it organised at Cardington. David was a hero for staying up all night on an IOP and then staying on to manage students in inflating the balloon. Many thanks Amanda and David.
- RGS DT department: thanks to DT department for their workshop space and the free use of their tools and being so patient when we left polystyrene all over the place. Thanks to Martin especially for helping us with the lazer logo cutting.
Interested in a HAB launch or weather stations for schools? Contact RGSweather!
short video version
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