INSUBCONTINENT EXCLUSIVE:

Tess Hatch Contributor Share on Twitter Tess Hatch hopes to travel to space, in the

meantime she is a venture investor at Bessemer Venture Partners, investing in frontier tech. More posts by this contributor The

evolving airspace ecosystem Space is open for business We have airplanes and drones in our airspace and satellites in space,

but what about the space in between: the stratosphere? There are platforms, such as blimps, balloons and high-altitude long endurance (HALE)

fixed-wing platforms that can duplicate functions now performed by drones or satellites in a more technically and commercially viable

manner. Commercial drones operate in our airspace below 400 feet

Commercial aircraft fly between 9-12km (30,000-39,000 feet)

Satellites operate in low Earth orbit (LEO, 500-1200km), mid Earth orbit (MEO, 2000-36,000km) and geostationary Earth orbit (GEO,

36,000km). But what about the vast space in between our air space and LEO? The approximately 488km of space known as the stratosphere, is,

at present, largely uninhabited and underutilized. The problem Imagine if a platform wants to loiter over a single point on the Earth for an

extended period of time, either to maintain situational awareness and consistent surveillance over an area of interest or maintain

communications

For example, after a natural disaster, it would be invaluable and life saving to have eyes, ears and a voice in the sky monitoring and

helping the afflicted

Or what if the platform were able to monitor a natural disaster before it made landfall to collect better data on the storm size, location

and path? Other reasons why it might be advantageous to have persistent real-time video from the sky is surveillance of vast maritime

regions and borders, identification of objects of interest and monitoring events, including storms, fires and environmental disasters, on

behalf of first responders and enforcement agencies. Another example could be global internet connectivity

If platforms mesh together and talk to one another, they could connect the world below in a much more effective and efficient manner than

ground-based fiber optic cables

It could monitor our oceans or protect vulnerable people from exploitation

And the potential military, intelligence and governmental applications are obvious and substantial. In short, the applications are abundant

and the potential market for this type of platform massive. Possible existing solutions Right now, the prevalent existing airborne platforms

are drones and planes, and the prevalent existing space-based platforms are satellites

Each platform has various benefits, but none are optimized for many of the missions described above and, thus, do not necessarily accomplish

those missions in the most efficient and effective manner. Quadcopter drone Pro: Cheap, close to the ground Con: Can fly for only on average

30 minutes (unless you are using Impossible Aerospace US-1 that has over two hours of flight time), needs access to the ground below, small

field of view from 400 feet, can be easily detected Image Credits: Impossible Aerospace Uncrewed plane Pro: Larger field of view from

30,000 feet Con: Can fly for only the number of hours fuel is available, expensive, can be detected Image Credits: alxpin (opens in a new

window) /Getty Images Constellation of LEO satellites Pro: Large field of view from 500-1,200km Con: One would need hundreds or thousands of

satellites in orbit for full-world coverage since the 90-minute orbits have access only over a single point on the Earth for ~15 minutes of

the ~90 minute orbit; also, the satellite needs to be successfully launched from a rocket, escape Earth velocity and operate for years in

the radioactive vacuum of space (which, while easier and less expensive than a GEO satellite, still requires a fair amount of effort and

expense) Image Credits: Spire Global GEO satellite Pro: Covers one-third of the Earth Con: Large (school-bus sized), expensive (many

millions of dollars), takes years (sometimes decades) to design/build/launch and does not provide the necessary low resolution or short

latency Image Credits: NASA/Leif Heimbold (opens in a new window) / Wikimedia Commons (opens in a new window) under a CC BY-SA 2.0 (opens

in a new window) license. The solutions above are optimized for other types of critical missions

For example, drones are great for monitoring crops or inspecting infrastructure (as Drone Deploy software enables) or delivering emergency

medical supplies (which Zipline and Google Wing are doing)

Remotely-operated planes like General Atomics MQ-1 Predator have offensive military applications. Constellations of LEO satellites in space,

like Spire Global, can provide maritime, aviation and weather monitoring and prediction, or take photos of the world, as Planet Labs does

Lastly, GEO satellites can also be used for monitoring weather, communication and surveillance, but at a high level, not localized. Possible

future solutions There are a handful of companies working on solutions specifically optimized for the mission of loitering over a single

point

These solutions include balloons, blimps and HALE (high-altitude long endurance) platforms in the stratosphere. Balloons Image Credits:

WorldView Companies like Loon, WorldViewand WindBorne use air currents in the stratosphere to loiter over a single point

Their platforms have no propulsion on board and the structure consists of two balloons, a lift and a ballast balloon

The lift balloon contains either helium or hydrogen and is sealed with special UV-coated material

They use a compressor to add or remove air from the ballast balloon so that it becomes lighter or heavier to make the balloon go up or down

depending on wind speed and direction and which air current they would like to ride. Pro: You cannot see these balloons from the ground with

the naked eye or with most types of current ground-based tracking systems

They are fairly cheap, can be launched easily and can loiter over a single area for days or even months at a time. Con: Without propulsion,

balloons are difficult to navigate through intense stratospheric winds, so it might be hard to precisely navigate and keep the balloons over

the specific area of interest

The balloons are not recoverable when the flight terminates, although when the balloon bursts and returns to Earth you might be able to

recover the payload. Blimps Image Credits: MR1805 (opens in a new window) / Getty Images Pro: They are fairly large so they can carry

heavier payloads and provide more power to the payload

You can re-land the entire platform to either fix or recover the payload, and launch it multiple times. Con: They can be seen from the

ground because they are so large, which makes them vulnerable to being shot down

Companies like Sceye and Altaeros are using the Goodyear Blimp with some tech upgrades

Their airships either have propulsion or are tied to the ground below, so they can better control where they are going, and they have

upgraded UV and ozone-resistant skin. HALE fixed-wing Companies like Zenith and Skydweller are working on high-altitude long endurance

(HALE) fixed-wing platforms

These high-aspect-ratio aircraft (which means long but slender wings) are powered by sunlight hitting the solar panels on the wings

The power that is generated can either power the plane and payload or be stored in the batteries

Therefore, if enough power is generated and stored during the day to last throughout the night, the plane can fly indefinitely. Pro: They

can be precisely controlled by a pilot. Con: They have limited power for the payload, as most of the power generated is needed to power the

aircraft. *TRL: technology readiness level For all of these platforms, there will be additional challenges in the areas of manufacturing

and mission management

The platforms need to be manufactured and launched cheaply, quickly and reliably

This takes time and money

Additionally, there are issues relating to who will monitor the platforms once they are in the stratosphere — the company that built the

platform or the customers whose payload the platform is holding? Another issue that platforms that operate in the stratosphere will face

relates to who regulates the stratosphere

Obviously, putting and operating platforms in the stratosphere raises a number of regulatory and legal questions that will have to be

resolved. I believe there is enough room in this market (and certainly in the stratosphere) for all of these platforms to be successful

They complement existing platforms such as drones and satellites and, for certain critical missions, can be more effective and efficient

than their counterparts that operate in the airspace or in LEO/GEO.

The space in between: The stratosphere