And they may also save lives - and economies - during the next global pandemic, too.
Now Dr Ogbonnaya Anicho, a scientist at Liverpool Hope University, has called for the systems to form part of all future pandemic strategic planning.
According to UNESCO, around 45 per cent of the world’s population still has no access to the internet.
In recent weeks the World Economic Forum warned how the Coronavirus pandemic had exposed the digital divide ‘like never before’, with billions unable to access school coursework, or to work from home.
And where there’s no terrestrial communications infrastructure, a High Altitude Platform Station (HAPS) – or sometimes called a ‘Pseudo-Satellite’ - could be the answer.
A single HAPS flies around 20 to 25km high in the Earth’s stratosphere, avoiding air traffic and adverse weather conditions.
It’s capable of providing wireless broadband coverage, via 4G from mainstream networks, to the ground below, covering a radius of around 100km.
Platforms vary, with firms like Google-backed Loon favouring a network of balloons, while Airbus Defence has spawned the ‘Zephyr’ - an unmanned, carbon fibre UAV with a 25 metre wingspan.
Now Hope’s Dr Anicho has developed a unique software platform that simulates a ‘swarm’ of autonomous fixed-wing solar powered HAPS with self-organising capabilities - meaning coverage areas can be extended significantly.
And Dr Anicho says these multiple HAPS systems, and HAPS generally, could prove crucial in coping with the next viral outbreak or natural disaster.
He explains: “In my humble opinion, I think Governments should acquire HAPS infrastructure for those strategic planning reasons.
“When there’s a natural disaster and the terrestrial infrastructure is compromised, first responders can quickly begin to use HAPS instead, as it can be set up on an ad-hoc basis.
“And in a pandemic, it’s essential you get emergency messages to people so they know how to stay safe. How do you do that if there are rural connectivity problems?
“This connectivity is also essential for industry and productivity, too.
“You can see that in most of the developed nations people have found it easy to migrate their work online during the Covid-19 crisis because there’s instant connectivity.
“Without connectivity, that doesn’t happen, and entire regions suffer.”
Dr Anicho, of Hope’s School of Mathematics, Computer Science and Engineering, knows only too well the dangers of a pandemic.
In 2014 he was working with a telecommunications services firm in Guinea, West Africa, when the Ebola outbreak was at its peak.
He adds: “We were mandated to remain active so that the country could keep its telecommunications infrastructure operational - as a key service to support the effort to combat the epidemic.
“It meant that first responders and medical practitioners could do their jobs.
“And right now, during Coronavirus, telecommunications allows the UK Government to provide daily advice updates and to share new insight from researchers. This crucial information doesn’t get through to people if they can’t access the internet.
“At Hope, the multiple HAPS coordination capabilities we’re developing is a small contribution to this field, but it’s also crucial. And on the pandemic management side of things, it’s really important.”
HAPS themselves first entered the scientific lexicon in the 1990s. But as Dr Anicho points out, it’s still very much a work in progress and there are still hurdles to commercial viability.
One of those barriers is keeping HAPS in the air for as long as possible.
Loon’s balloons, so far, stay in the stratosphere for around 150 days.
Airbus’ solar powered Zephyr holds the record for longest continuous flight by a fixed wing HAPS platform – at just 25 days continuous operation.
Dr Anicho is hoping to get to a point where fixed wing HAPS can remain in the sky for months or even years.
He adds: “There are different HAPS technology problems to address. Some might look at how to optimise materials in order to save weight. Others want to find the right kind of platform, whether fixed wing, balloon or aerostat.
“What makes our software and simulation platform unique is that we’re looking at the multi-HAPS concept – because to cover a country or wider region, you need a swarm. You can’t do it with just one HAPS.
“And we’re developing the capability for multiple HAPS to coordinate autonomously.
“Practically, to operate one HAPS you need up to four people, or perhaps even more, depending on the type of platform, mission profile and other operational requirements.
“For HAPS to become truly commercially viable and realistic, this human price component needs to fall.
“We’re finding algorithmic or technology-based solutions to coordinate several HAPS with minimal human input.”
Dr Anicho is quick to point out that solar powered HAPS – which cruise at speeds of around 110 km/h, or around 68 mph - won’t work everywhere.
There are constraining solar variations across seasons and geographical areas.
But HAPS will be relevant for many of the developing nations who need it most.
And for Dr Anicho, it’s now a question of raising awareness about what HAPS can achieve – and changing government policies to improve adoption.
He adds: “HAPS technology is still not common knowledge. And it’s my view that we need to get the message out there.
“One of the main reasons why there are rural connectivity challenges is that operators are not interested in building terrestrial infrastructure because of the high investment cost and very poor commercial viability of doing business in those places. They’re reluctant to invest.
“There are also relevant policy challenges. Our approach is to address both the technology and policy questions in order to reduce the barriers, enabling operators to scale up easily into those areas.
“This is my vision. This is what we’re trying to achieve.”
At this point Dr Anicho’s research is looking at four or more HAPS to create a ‘swarm’ - as well as how to improve power management - in his simulations.
HAPS use energy from the sun to charge the batteries during the day, which in turn powers the craft at night.
Long term, the University’s HAPS research team also hope to build a prototype of a solar-powered UAV, subject to funding.
In the meantime it is procuring small-sized drones for use in the experimentation of multiple UAV-type problems, like routing and coordination.
The cost of a Zephyr is said to be around £4.3m – significantly cheaper than the cost of an orbital telecommunications satellite, which can cost between £40m - £325m to build and launch.
HAPS meanwhile has uses beyond communication.
The Ministry of Defence has purchased several Zephyrs for surveillance purposes, while they could also be utilised for everything from mapping to weather prediction services.
Dr Anicho has also garnered interest from the Commonwealth Telecommunications Organisation (CTO), where he engages representatives of governments, policymakers and regulators on the strategic position of HAPS for addressing rural broadband connectivity challenges.