Weekly Balloon News #13
April 6th, 2023
Recent balloon launches and landings
These are the balloon missions performed during the last week of March and the first days of April, in chronological order.
On March 29, Aerostar the South Dakota-based balloon firm launched from the small airfield located near Hurley (SD) a #Thunderhead balloon under the callsign HBAL-622. The flight was very short -8 hours aloft- and ended very close to the small settlement of Swedona, Illinois.
On March 31, World View (WV) made the second launch of a Stratollite balloon from the Big Island of Hawaii. The balloon was launched from Waimea-Kohala Airport and as occurred with the first one launched four days before it soon cleared the island’s shore and entered the Pacific Ocean.
The balloon was meant to travel approximately 4,000 nautical miles, performing station-keeping demonstrations over predefined sites, to end with a landing in the United States within 60 days of the launch. Both flights fell under the umbrella of Project Aether, an initiative carried out by WV and defense contractor Sierra Nevada Corp. to explore how to effectively operate in the stratosphere using high-altitude, long-endurance unmanned air systems.
However, things appear not going as expected with both flights.
A few hours after being launched, the second balloon (n139wv) started to lose altitude steadily reaching merely 35.000 ft just at the moment of exiting the ADS-B grid (due to lack of coverage).
That made me examine the data available from the first flight (n137wv), and although the decrease was not as sharp as in the second flight, the flight data showed that this Stratollite too started to lose altitude a few hours after launch.
A few hours before this newsletter publication a representative from WV confirmed that unfortunately, both missions encountered an issue that resulted in the inability to maintain sustained flight, and despite best attempts to navigate the systems for a land-based recovery, a remote area was selected in coordination with FAA authorities to conduct a safe, controlled termination of both balloons, which now lies in the bottom of the Pacific Ocean.
What could have gone wrong? 1
Although details were not provided by the WV representative, some sources in the field whom I consulted, pointed to a possible failure in the compression system that inflates the super-pressure balloon system.
For those unfamiliar with the Stratollites operated by WV, the system consists of a modified zero-pressure balloon (ZPB) with an air ballast pumpkin super-pressure balloon (SPB) attached below it.
The ZPB provides initial and sustained lift for the system from launch to an altitude of about 75.000 ft. The SPB located right below the ZPB is a pumpkin configuration that operates at a positive internal pressure in comparison to the external atmosphere and provides the system with a variable amount of effective ballast by pumping in or expelling out ambient air.
After reaching maximum volume altitude (both of the flights launched from Hawaii were very close to the limit on which the ZPB would reach its maximum expansion) to keep it from failing (bursting), mission control had to open the gas valve which mean that there wouldn't be enough gas to fly as an altitude control balloon.
Because something about the anchoring system failed; the SPB did not inflate and pressurize possibly because:
The communication link failed
The compressor failed to operate
The SPB had a leak
The “new” high-humidity environment for the operation of the Stratollite system could have contributed to the failure.
It is possible that in such a humid environment there was a lot of water condensation inside the SPB from the initial air volume pumped into it on the ground and subsequent air pumped in at low altitudes. That water would run down into the air valve and compressor; not an ideal situation especially when it got cold enough to freeze.
Another option could be that the water condensation froze and damaged the film of the SPB provoking a leak.
I wish to emphasize that this is the opinion of experts outside the company and that we must wait for WV to issue an official word on the matter -if it does-. Regarding the origin of the failures, I’ve learned that an investigation is underway.
The WV representative also stated that the purpose of this series of flights was to continue the maturation of the Stratollite system in a new operating environment. The data and learnings acquired during these tests will be used to further the designs and operational aspects for future flights.
Finally, on April 3, Aerostar launched a second Thunderhead balloon from the small airfield near Hurley (SD). As occurred with the previous mission, the flight was also very short -8 hours aloft- and landed in Minnesota, a few miles SW of the town of Austin.
What’s on in the field
NASA announced this week the opening of the launch window for the first of the two balloon missions to be carried out from the Wanaka airport in New Zealand. Since 2015, the agency selected the airport as its launch base for the long-duration missions of their Super Pressure Balloon across the southern hemisphere.
So far 3 missions were performed:
The first technological flight of 32 days in 2015
A second mission in 2016 transporting a scientific instrument called COSI which flew for 46 days
A third mission in 2017 with the EUSO-SPB instrument which flew for 12 days before sinking in the Pacific
The next planned campaign in 2020 was canceled due to the COVID-19 pandemic, and the last attempt in 2022 ended without a launch due to a ground system anomaly.
This year’s campaign will try to launch two balloons during the same campaign for the first time. As mentioned before the balloons used -manufactured by Aerostar- are of the super pressure type, pumpkin-shaped with a volume of 18.8-million-cubic-foot (that is 532,000-cubic-meter). They are filled with helium and about the size of a football stadium when fully inflated. Its constant operational float altitude is 110,000 feet (or 33.5 kilometers).
The scientific instruments that would take part of this campaign are:
SUPER-BIT (SUPER-pressure Balloon-borne Imaging Telescope) a highly-stabilized, 0.5-meter wide-field, diffraction-limited balloon-borne telescope that operates in the stratosphere in order to obtain space-quality imaging of high resolution. With optical sensitivity from the near-infrared to the near-ultraviolet, SuperBIT aims to make precise weak gravitational lensing measurements of galaxy clusters in order to infer the presence and relative quantity of dark matter in these clusters as well as the large-scale structure of the universe. To achieve high-precision measurements the SuperBIT gondola stabilizes its telescope to sub-arcsecond precision while sophisticated optics further stabilize the SuperBIT camera to < 50 milli-arcseconds. The instrument is a development of the University of Toronto with the collaboration of the Princeton University, and the Durham University.
EUSO-SPB2 (Extreme Universe Space Observatory on a Super Pressure Balloon 2) an improved version of the instrument that flew also from Wanaka in 2017. EUSO-SPB2 will monitor the night atmosphere of the Southern hemisphere from 33 km of altitude to detect Ultra-High Energy Cosmic Rays (UHECRs) and search for astrophysical and cosmogenic neutrinos. The instrument is designed with two telescopes: a nadir pointing Fluorescence Telescope and a Cherenkov Telescope pointing towards the Earth's limb.
The instrument is part of the Joint Experiments and Missions for the Extreme Universe Space Observatory (JEM-EUSO) program which encompasses a scientific collaboration effort that includes 350 scientists at 93 institutes and universities from 16 countries.
Depending on weather and prevailing winds, the balloons will move in an eastward path across the Pacific Ocean, crossing South America probably above the Patagonia region and across the Atlantic and the Indian Ocean back to the Pacific.
NASA identified the first launch opportunities for SUPER-BIT starting in the week right after easter.
HALO Space, the Spain-based company that will intend to offer balloon-borne tourist flights in the near future announced the second test of their capsule that will be carried out during the first half of 2023 in southern Spain.
As you will remember, the first flight of the capsule was performed from the National Balloon Facility in Hyderabad, India in last December.
Besides the typical marketing-fueled press release, no further details were disclosed on the upcoming test. The company stated that their plan is to start commercial flight operations in 2025.
A team of future engineers and computer scientists at California State University, Fullerton are developing a balloon-borne capsule aimed to perform scientific experiments in microgravity environments. This will be achieved by dropping the capsule from 150000 feet, or 28 miles high.
The group is focusing its efforts on affordable, rapid-deployment, microgravity experiment platforms for smaller industries, research groups, and universities.
Below these lines, there is a scheme of the internal structure of the Sub-Orbital Launch and Recovery (SOLAR) System capsule that will host scientific experiments and other important subsystems to recover scientific payloads.
The group will build a prototype of a 25-pound capsule, about 3 feet wide, which will carry future microgravity experiments. The capsule, or Recovery for Avionics and Payload Retrieval vehicle, will be attached to a medium-sized helium-filled balloon and dropped from the stratosphere. Following the freefall period the capsule will deploy a drogue and main chute, and then drift back to Earth for recovery and payload collection.
The first flight test is planned for the late part of 2023.
The city council of Timmins, recently approved an interim lease agreement with the Canadian Space Agency (CSA) while the construction to expand the Stratospheric Balloon Base continues at the Victor M. Power Airport. Once that work is completed, the city will finalize its lease with CSA which will incorporate a recouping of costs for the construction.
The expansion work started in 2022 and included the construction of an additional payload integration hall and the addition of an elevator to the existing building. The city council awarded a $ 4.1 million contract to Cochrane-based CGV Builders Inc. which is in charge of the modifications.
Meanwhile, the agency disclosed the official logo for the upcoming balloon launch campaign that will be held this year with the French Space Agency CNES.
That’s all for this edition folks! Stay tuned next week for more balloon news -including recent aftermaths of the Chinese balloon affair and big additions of data of past balloon missions to Stratocat.
If you consider this newsletter useful spread the word among those you consider will be interested in reading it.
See you in seven days.
This part of the newsletter was updated on April 6, 14:00 utc
What software did you use to plot those WV tracks like that?! So cool!