Flying To The Rescue: the technology of personal flight takes a leap forward

Social media was alight last week after a video released on Wednesday captured a “jet suit” mobility test in the United Kingdom. These tests were carried out by members of the private aeronautical company Gravity Industries, on behalf of the Great Northern Air Ambulance Service.

The video, accessible on YouTube, depicts a trial scenario. Two hillwalkers are enjoying England’s Lake District when one sustains an injury and the pair call the ambulance service. The Lake District is one of the UK’s most popular national parks, attracting over 19 million tourists in 2018, and one of the largest. The park covers 2,362 square kilometres of wild terrain – a beautiful but sometimes dangerous combination of lakes, pools, forests and mountainous outcrops.

According to the GNAAS’ website they responded to over 1600 emergency calls in 2019, but the rate of their response to each call is heavily dependent on the location of the injured party.

In the video, an ambulance crew arrives by car, getting as close to the patient as their vehicle will allow. The imperilled hillwalkers are some distance away, separated from their rescuers by a long and difficult uphill climb.

One paramedic is strapped into a surprisingly light contraption that fits on to his upper body. A small engine protrudes from his back, and large cables attach to a pair of cylinders on either arm. He stands a little distance away from the other paramedics.

The grass flattens around his body. The engines heat up and in 45 seconds he hovers into the air. He flies smoothly up the hill. It takes him 90 seconds to find the pair of hillwalkers.

Trevor Young is an Associate Professor in aeronautical engineering at the University of Limerick and a member of the Bernal Institute. Besides teaching aircraft design, he also flies recreationally.

“As I watched the video, I admit I had to look carefully to see if it was genuine. Humans flying with ‘jet suits’ has been a favourite theme of science-fiction authors for decades. Scepticism is natural. What Gravity Industries have achieved in less than five years is remarkable.”

The pilot in the video is the founder of Gravity Industries, Richard Browning. Browning, a 41-year old who lives in Salisbury, worked for BP Oil and was a Royal Marine Reservist before he started his business in 2017.

His family’s lineage provides a clue to his current occupation. His father was an engineer and pilot, and his maternal grandfather was Sir Basil Blackwell, the renowned bookshop magnet, who began his career working on jet engines for Rolls Royce after the second world war.

Pedigree aside, Browning tells me that the idea for his invention was conceived during his stint in the Royal Marines.

“My experience taught me a lot about human capability – it’s amazing what you can train a body to do. This insight led me to the idea of personal flight back in 2016. I started to think about the brain as a flight computer, and the body as its structure. I wanted to find out if someone could learn to fly in an organic and natural way. Rather than sitting inside or on top of the flight machine, I wanted to become the flight machine.”

The experiment started in March 2016 when Richard bought his first jet engine. He tinkered with the device on evenings and weekends. After a parade of prototypes, Richard built the Mark 1 suit, also called the Daedulus, which was an admittedly “crude” combination of small gas turbines on the pilot’s legs and arms. He achieved his first flight in November 2016.

The current Gravity Industries jet suit is the second-generation model of Browning’s design. The company uses 3D printing processes to manufacture the suit out of polymer, aluminium and titanium.

The Mark 2 suit consists of one large jet engine worn on the back and a pair of micro jet engines on each arm. The style of flight achieved by this combination is what has earned Browning the nickname of Iron Man, after the superhero played by Robert Downey Junior in Marvel’s popular Hollywood franchise.

“The jet suit is controlled by vectoring, meaning you control your flight by altering the direction of your arms. You point your arms down to go up and move your arms a little out to the sides, or ‘flare’ them, to go down.

All the control, the fine movement, is achieved by moving your arms. As soon as you move your arms, you change the relative angle of the rear jet as well, like when you move the front leg of a camera tripod – the relative angle of the back pair also changes.”

Browning’s determination to ‘become the flight machine’ is what makes his invention so striking. He has succeeded in constructing a personal flight device that is portable and lightweight. This was crucial, according to Professor Young, to achieve his aim. “An important parameter for flight is thrust-to-weight ratio.

This is why it has taken so long to develop this technology – you need to be able to produce thrust at a very low weight. Birds, for example, have superb lightweight skeletal structures, with a high ratio of muscle mass to total mass. Small engines capable of generating large amounts of thrust are a recent phenomenon.”

For Browning, the sensation of flight “is still an amazing experience. You squeeze the power on and feel your weight get lighter and lighter. Suddenly you’re off the ground, and you can genuinely move however you like – it’s complete three-dimensional freedom.”

The feat of engineering is impressive, but what is more incredible is how effortless Richard’s design makes the action of flight.

“The control becomes very intuitive, not dissimilar to how effortless it becomes to ride a bicycle. You don’t worry about steering or manoeuvring, you don’t worry about where you’re going to go – you just look at the path you want to go down and you go there. There’s no stress or strain, you’re really just leaning on those arm engines. It’s like leaning forward on a kitchen table or bathroom sink. It’s no more stressful than that.”

As soon as you understand what Browning and his team have managed to create, the possibilities of the technology seem endless.

“When I started experimenting, and even when I started the business, I had no thought of the practical applications. We’ve now done 108 events in 31 countries and the impact has been huge. As the audience grew, we decided to build a race series, like Formula 1, and have the pilots compete against one another. After all, Formula 1 cars are fantastic sources of entertainment and inspiration for people all over the world.”

“Looking ahead, it’s clear that the scope for the technology’s application is very broad. We started to work with the ‘search and rescue’ emergency response services, to see how our design could be integrated into their sectors. Our collaboration with the Great Northern Air Ambulance Service is one such example.

They reached out to us about nine months ago because they wanted to create a new role within their organisation; one that had unique mobility. The obvious point of comparison is the motorcycle paramedic in cities and towns.

Those guys cut through traffic and get the expert to the site of the casualty very quickly. That’s the critical thing: you must get the medic at your side as soon as possible. Anything that reduces the wait-time is hugely advantageous, and as you saw, our suit facilitates a speedy arrival.”

Another factor contributing to the success of Richard’s design is its safety. The suit burns jet or diesel fuel, both of which are “non-volatile… Jet fuel, for example, does not have a tendency to form a vapour cloud and is very stable, which is the reason it’s used in aircraft.”

Nor is the heat from the exhaust of the jet as dangerous as you might expect. “Air has a very low specific heat capacity. If you get a hairdryer, turn it on and press it directly against your head, your skin will burn. If you hold the same hairdryer two feet away from your head and point it in that direction, you’ll barely feel the warmth.

Air loses heat energy very quickly, unlike steam or water. So, while it might be 700 degrees inside the engine, the temperature is down to a very safe level within a couple of feet. You can swipe the thrust across your jeans for instance, and as long as you don’t hold it there, all you’ll experience is the forceful push of air.”

That said, we’re not likely to see the jet suit become a common mode of transport any time soon. To reduce risk, the Gravity Industry team is careful to limit the kind of terrain they fly over to grassy meadows and expanses of water, and they try to remain at as low an altitude as possible.

Professor Young also points to the problem of weather. “All pilots know how difficult it is to land a plane when it’s gusty. I imagine that the suit’s performance is not compatible with strong winds.”

Another restriction is fuel transportation. Given that the pilot needs to be able to execute quick manoeuvres, they cannot carry vast quantities of fuel, so the suit can only fly for a couple of minutes at a time. This limitation is offset by the pace at which the pilot can fly – the equipment’s top speed is 136 km/h.

Browning is also keen to point out that the length of the flight time will be doubled when the company releases the Mark 3 suit later in the year.

“The new model is now flying and it’s very exciting, if I may say. We have managed to leap over various milestones. The Mark 3 suit is smaller and lighter, and it generates 20 kilos more thrust than the current model. It also takes only 10 seconds to start, which means we’re closing the gap between the intention to fly and flying. For me, that is very special.”

Post by Tom Lordan.  Tom is a freelance journalist who writes about philosophy, politics and the arts. You can get in touch with Tom on Twitter here, Instagram here and LinkedIn here.