Notes from the Curators Office:
a Jet Pack
I fly like Dan's Steven's Rocketeer?
My dream of flying through the air like the Rocketeer was
just a fantasy -- until just a few weeks ago.
(8/14) Back in an article I wrote in February of
2007 I asked the question "What Ever
Happened to the Rocket Belt?" In that piece I lamented that
while growing up I'd seen Buck Roger's inspired personal aviation
devices featured in movies and science magazines. Everybody seemed
to think we would have them by the 21st century, but they never
materialized. The few jet packs that were actually built and flown
back in the 60's were impractical and cost hundreds of thousands
dollars. And even with that immense amount of money, they could
only give you a flight of about 30 seconds.
Well, somebody has finally figured out how to build
a real jet pack and I've actually flown it. Admittedly it comes
with a few restrictions. Still, it actually flies and almost anybody
can try it out.
Before talking about my experience, let me recap
the rocket belt/ jet pack situation up to this point.
of the Flying Jet Pack
The idea of flying by strapping a rocket to your
back often appears in the pulp stories of the 1920s. Of course,
that was just fiction, but after WW II an engineer named Wendell
F. Moore of Bell of Aerosystems, working under a government military
contract, actually built one that could carry a man. The design
was ingenious and test pilots reported that the unit was very
stable and easy to fly. The pack carried tanks of hydrogen peroxide.
When the hydrogen peroxide was forced through a metal catalyst
it would break down into steam and oxygen. The steam took up a
lot more space that the original hydrogen peroxide and under pressure
came shooting out of two nozzles just behind the shoulders of
the pilot. The thrust from these downward facing nozzles lifted
pack, and the pilot attached to it, into the air. Control of the
device was achieved by two rods that ran forward from the sides
of the device to handles that the pilot could grip. By moving
these rods up and down the pilot could change the position of
the nozzles and giving him control over moving forward or backwards.
By pushing one up, and the other down, he could even spin in the
original rocket pack in testing.
The problem with Moore's invention wasn't in controlling
it, but with its range. The hydrogen peroxide fuel was exhausted
in 21 seconds. This made for some wonderful demonstrations, but
few practical applications.
Moore later built a similar device using a jet engine
for lift, rather than the rockets. Engineers expected that the
jet version could fly for a long as thirty minutes, solving the
range problem. However, a jet engine is less reliable and requires
more maintenance that a rocket. Since a failure of the jet pack
at any significant height meant sever injury or death for the
pilot, the military soon lost interest. The one jet pack that
had been built by Moore wound up as a curiosity in a museum. People
built a few rocket packs, but these were only used for publicity
stunts, or short appearances in movies or TV shows.
A few years ago, however, Raymond Li, a Chinese-born
Canadian from St. John's Newfoundland read about Moore's work
and became interested in the idea of a jet pack. In 2000 he sketched
his idea for getting around the range problem onto a simple "post
it" sheet. The difficulty with the rocket pack to this point was
that you couldn't carry enough propellant on it to sustain a long
flight. Suppose, however, you sent the propellant up to the pack
through a long hose? The pack would be limited to the height that
the hose could reach, but your flight could be as long as you
Li's idea evolved into a jet pack that used water
instead of hydrogen peroxide. Instead of creating the necessary
force by converting the hydrogen peroxide to steam, a ground based
pump powered by a diesel engine provided the pressure. This would
mean that the jet pack would be a lot cheaper to operate and pilots
would not have to worry about being burned by the steam shot from
the jet pack's nozzles as the nozzles would be expelling cool
Although Li at first considered the military as
a primary customer, the fact that the device worked so well over
water (with the pump and engine trailing behind the pack on a
float) made it a natural contender as a recreational watercraft.
It took him until 2011 to perfect a prototype and get it into
production with the help of National Research Council of Canada.
The device was marketed as the JETLEV R200 and cost over $100,000.
A recent upgrade, the R200x now retails at $69,000.
I first became aware of Li's work earlier this
year when I saw it appear in the media in several places including
a segment of the popular TV show "Hawaii Five-0."
up and ready to fly. Note the orange boat-like float behind
me carries the engine and the pump. (Copyright
Lee Krystek, 2014)
Flight in the Keys
During a expedition to the Florida Keys this spring
I got the chance to try it out for myself though a company called
Tikijet located in Islamorada. The owner of Tikijet, Jason, took
my wife and I out on his pontoon boat about a ¼ mile off the coast
in water that was around 10 foot deep. Once we were anchored in
a zone reserved for jet pack flights, he gave me a run down on
the operation and on control of the device.
The pack's controls are set up almost identically
as those of Moore's rocket belt. You hold your arms out in front
of you gripping handles on two control rods. Each rod is directly
connected to the nozzle behind your shoulder. Pushing the rod
upwards aims the nozzle a little forward giving causing you to
drift backwards. Pushing the rod downwards caused the nozzle to
point slightly backwards giving you forward movement. The controls
were fairly sensitive and required subtle movements (For example,
pulling up radically on the controls could cause you to do a dangerous
Turns could be made by moving forward and then pulling
up slightly on one rod and down on the other. Because the controls
were so sensitive, however, Jason recommended turning instead
by shifting your body weight to one side, or the other, which
achieved the same result.
After being carefully strapped into the jet belt
I jumped into the water being careful to clear of the edge of
the boat so that the pack didn't get caught on the gunnel. Jason
requires pilots to wear a life vest so I quickly popped to the
surface. The only surprise was that since the jet pack also floats
you have a tendency to find you face underwater unless you actively
tread water to counteract the buoyancy of the pack.
This brings us to an important point. One of the
requirements, I believe, for a successful flight, is that the
pilot needs to be extremely comfortable in, around and under the
water. Someone who is nervous about being dunked may be too distracted
to successfully operate the pack.
not the Rockteer, perhaps I could be James Bond. The helmet
For my first flight Jason equipped me with a helmet
with a radio receiver in it (Unfortunately the helmet wasn't brass
colored with a fin down the center like the Rocketeer's). The
radio allows him to give pilots step-by-step instructions as they
learn to fly. On this initial flight he also controlled the throttle
(which varies the amount of water being shot out the nozzles and
therefore the lift) remotely from the boat. This was helpful as
it gave me one less thing to worry about. On later flights pilots
can control the throttle by turning the right-hand grip, in the
same manner the throttle is worked on a motorcycle.
Each flight starts with the pilot keeping the control
handles just out of the water as Jason increases the throttle
settings. I found myself first moving forward through the water
chest deep, then flying with half my body still in the water,
and finally out of the water completely.
The engine and pump, in a float the looks like a
small orange boat, trailed behind me connected by a 33 foot long
hose. This allowed me a maximum height of about 30 feet when I
was hovering. Generally the pack is most stable, however, when
you are moving forward as the drag of the float help steady you,
so you are usually flying at a lower altitude, perhaps 10 to 20
The sensation of flying the jet pack was exhilarating
and unlike almost anything else I've ever done. I've ridden a
number of zip-lines, which are in some ways similar in that you
are hanging suspended high in the air. However, a zip-line ride
lasts, at best, 15 or 20 seconds. I was up flying the jet back
for over thirty minutes (barring a couple of accidental falls
into the water). Even more importantly, you have no control on
a zip-line about where you are going. With the jet pack I had
complete control over where I could fly it with the limitations
that I couldn't leave the immediate area or get too close to the
boat (You don't want your hose to get entangled with the vessel.
Falling from 30 feet into the water is no big deal. Falling onto
the boat from 30 feet would hurt a lot).
Bond for Forty Minutes
From the pilot's perspective it was easy to forget
you were attached to the float/pump by a 30 foot hose as it is
always trailing behind you. With that out of view it doesn't take
much effort to believe you are flying around just like James Bond
in the 1965's Thunderball. In fact, Jason recommended humming
the Bond theme as I flew along circling his boat.
up and away! (Copyright Lee Krystek, 2014)
My biggest crash into the sea occurred when Jason
asked me to signal that everything was okay by waving my hand.
Attached to the pilot's right wrist is a strap that is connected
to an emergency stop switch on the pack's control arm. Move your
arm too far from the grip and the connection is broken, turning
the engine/pump in the float behind you off. Forgetting that this
was attached to my wrist I lifted my right hand and waved, with
the predictable results. From the laughter on board the boat from
Jason and my wife, I suspect that the suggestion that I wave,
without reminding me to use my left hand, was intentional.
In his promotional materials Jason claims that most
people can learn to fly the pack in three to five minutes and
I have to admit that this was my experience. The limiting factor
for how long you can fly (the float can hold about 3 hours of
fuel) is mainly the comfort of the bicycle style seat the carries
most of your weight. According to the JETLEV company website,
there is an option on some models to include a bar they goes below
the pilot's feet so that he can stand and relieve some of the
pressure from the bicycle seat, but the unit I flew didn't have
There are lot of tricks you can try with the jet
pack, though with my first flight I tried to concentrate on getting
and maintaining complete control over the device and not crashing
into the sea. Jason did talk me into trying "walking on water"
a maneuver where you skim the sea and move your legs as if you
are running on the sea. Another trick that you do is to allow
the pack to act as an engine to propel you underwater like a submarine.
This is a maneuver, of course, that would be impossible to do
with a traditional rocket pack.
I was so confident with flying after about 30 minutes
in the air I let Jason talk me into trying a spin. In this maneuver
you hover for a moment, then for a second push one control run
all the way up, and the other all the way down causing you to
quickly pivot around. Though it took me two tries to perfect this
trick I was successfully able to spin in place without getting
full flight. (Copyright Lee Krystek, 2014)
Because you are over water landing the jet pack
is a cinch (Something that is a harder with a regular rocket belt.
In fact, Moore broke his knee cap in a bad landing with the original
pack). The throttle was slowly reduced as I pushed a bit down
on the control arms. I and the pack then dropped gently into the
water. By turning the release buckle on my chest I could pull
away from the pack leaving it to float by itself. Jason then simply
pulled the pack back on the boat, while I swam to the ladder on
the aft and pulled myself aboard.
The flight wasn't cheap. $180 got me an experience
that lasted almost an hour and a half with a 40 minute flight
time. Still, it's that type thing few people get to do and is
the chance to accomplish something usually reserved for the hero
in Science Fiction fantasies. It's also gives you the ultimate
response to the question: "What did you do on your summer vacation?"
Copyright Lee Krystek
2014. All Rights Reserved.