The Zero Gravity flight for the flexible fuel hose experiment
Intro and background for
this project is on this page.
Arrival at the Airfield
We arrived at Building
990 at the Ellington
Air Force Base,
which is located right next to NASA Johnson Space Center on May 30,
2013. This is where we will do our final assembly and from
where
the plane departs for the parabolic flights over the Gulf.
View of the hangar with the NASA
C-9 research aircraft.
This plane also does parabolic flights, but we will not be
taking
this one. We were told that unfortunately, this plane would
be
put into storage.
The
next day (5/31/13), the rest of the participants arrived, and shown
here was the morning all-hands meeting to kick off our adventure.
Two
of our mentors for the week. Frank Prochaska (left), who runs
the program
for the education
office,
and Dominic Del Rosso, who runs the entire facility. Not
shown is
Paul de Leon, who mentored the Flight Opportunities Group.
They
are very strict on tool and parts control. All tools must be
signed out and everything is grounded if any are missing. As
you
can see, all tool boxes are 'shadow boxed'.
We performed our unpacking and final assembly in the hangar.
What a great backdrop.
Since
we arrived one day before the rest of the other projects, we were able
to do our final assembly in a relatively quiet environment.
One of the most important pieces of hardware is this 3D motion tracker
from OptiTrak
corporation. It will be used to track the motion of
the flexible hose.
After
many months of preparation, it felt really great to be in Houston, and
in Hangar 990 at Ellington Field. We found out there that we
would be taking part in a special edition of the zero G flight.
NASA has always had separate projects to fly students and
professionals doing research. We found out that this campaign would be
the first to combine the two projects into one flight. The
students were known as "Education
Flight Program", while we career guys were known as "Flight
Opportunities Projects (FOP)".
Although I could not compare otherwise, I really enjoyed the
interaction with the students, and was grateful for being on this
campaign. I would soon find out that this week would be one
of
the best on a professional and personal level. We had arrived
among fellow flyers and researchers, and every day, the atmosphere in
the hangar was electric.
Half of the plane will be in use by the education office projects.
Here we are
explaining our experiments to member of the team from
Oklahoma State University.
It was really great to see the experiments from the students, and to
share their excitement in the hangar. Image from Twitter.
Since
we were near JSC, we decided to look around, and here we are at the
site where astronauts train in the water to simulate the weightlessness
of space. This is the Sonny
Carter Neutral Bouyance Laboratory.
In the huge Saturn V display near the entrance of Johnson.
Loading Day
On
Monday 6/3, we had our final Test Readiness Reviews, and afterwards
received approval to proceed to loading the
plane with our hardware. We also receive our flight suits on
that day.
Morning
breaks on flight week (6/3), and it was a beautiful day. We
arrived at
the hangar and saw that our plane had arrived. She looked
really beautiful.
This is the team I headed up for the flex hose investigation, including
the spare flyers.
The new ones are Mike Oetken (middle) and Erik Tormoen (right).
Flyers for a serious mission.
Every day, we have mission briefings at 7:45am sharp for the team leads
in the mission briefing room in nearby building 993.
We receive our flight suits on Monday 6/3. A few months
before
I bought the flag of Aruba in a patch form.
At
the end of Monday (6/3) we completed the loading of our hardware onto
the plane, and are located all the way in the front. You can
see
the OptiTrack sensor on the front right, and the computer that runs all
the hardware in the bottom right. We are excited and
happy to get to this point.
In
the above image, you can see the laptop that was used to run the
electronic gear. One interesting note is that we had to use a
computer with a solid-state drive (SSD). This is because
modern
laptop have a sensor
that safes the disk drive
in the event that it detects it has been dropped. On a
previous
flight, another team found their laptop stopped working because this
sensor detected the transition into zero gravity, and their computer
shut down.
Flights in Zero Gravity We
had four flight days from 6/4 to 6/7. The daily routine was
approximately as follows: we would arrive at around 7am at the hangar
(Building 990), and I would attend the team-leads meeting at
7:45am in the mission briefing room (Building 993).
Afterwards, I
would brief my team
mates back at the hangar, and then the flyers for that day would go to
the medical
briefing at 8:15am back in 993. This is where the flight
doctor
gave us instructions on how
to avoid motion sickness, and where he would administer an optional
shot of Scopolamine.
We would then return to the hangar to pick up our gear, and
line
up next to the tarmac in a single file. As we board, we walk in a
single file to allow the photographers to get a good shot of each of
us.
Although most of the cabin is open, there are rows of seats
in
the back of the aircraft, and that is where we are seated. As
we
walk into the plane, our identity is checked, and we are able to pick
up some hard candies for snacking (more on that below). We
would
usually take off around 9:50 am, and we are allowed to get up from our
seats and walk to our experimental setups as soon as we hit 10,000
feet. This is a strange feeling as the plane is still
climbing,
and you are basically walking uphill on the padded floor of the plane.
We would fly out to Matagorda
Bay,
and then turn South over the Gulf of Mexico. While flying
South,
we would perform 16 parabolas, take a few minutes to turn around, and
fly another 16 on the way back. On each day we would usually
do
30 parabolas in zero gravity, and then one in Lunar, and one in Martian
gravity (so 32 total per day). We would then land in the
afternoon, and rest and prep for the next day.
The
flight path for our zero gravity flights. We take off from
Ellington (top of the image). Once we get over
Matagorda Bay, we turn South. At that point we start the
parabolic trajectories, doing 16 of them on the way out.
There is
then a turn around (bottom of image), and we do another 16 on the way
back.
The parabolic curve we flew.
Medical Assistance with Motion
Sickness
The
medical doctor gave us the option of taking Scopalamine to counteract
motion sickness. This was highly recommended, and could be
taken
orally or by injection. The former would take longer to take
effect, and would take longer to get out of your system, so as a
result. I chose the second option every day. The flight
doctor
also flew with us, so he could keep an eye on everyone.
On
the first flight day, I took a full dosage for my weight of
0.2mg, and found out after 15 minutes the extremely debilitating
effects of the drug. My whole world was spinning and I was
walking unsteady, and I wondered
how I was going to do on the flight. On subsequent days, I
would
cut my dosage to the minimum of 0.1mg, and did much, much better.
Another aspect (as we were warned) is that the boarding of
the
aircraft gives you such an adrenaline rush that it partially
counteracts the debilitating effects, which also helped.
Another
effect of the Scopolamine is that it gives you a very dry mouth, so I
used hard candy to counteract this side effect. In the end,
the downside of the drug was
worth it as I never got nausea during the flights, and racked up 120
parabolas in zero gravity (a total of over 40 minutes in zero gravity),
and several
parabolas in Lunar and Martian gravity without getting ill.
However, after a few days of taking the Scopolamine (I flew
every
day), I could sometimes feel the floor moving when I walked up and down
stairs, or when I dipped my head down and up. I did not mind
it
actually, as it was a constant reminder that it was flight week and the
associated excitement.
We
are also briefed that the most critical part (as far as motion sickness
is concerned) is the short 2G period between each zero G portion.
A very important measure is to keep your neck straight during
this time, so that means do not tilt your head back or forward during
this time. You are allowed to move your shoulders and neck
together to look around, but it is very important not to tilt your head
during the high G period.
First
flight day of our campaign. It felt so strange to be first at
around 2 Gs, and then into Zero G. We flew for 30 parabolas
lasting a few minutes at zero G, and one at Martian, and one at Lunar
gravity for the other experiments.
The Sensation of Zero Gravity
The
sensation of zero gravity is produced by the lack of feeling any forces
from your surroundings. To do this on Earth, you need to put
your
body into free fall so that everything arounds you experiences the same
downward accelleration due to gravity. This is the same thing
that occurs to astronauts in space except the constant falling motion
produces a circular orbital motion around the Earth. This article on
Wikipedia
has more info. On the plane this occurs by essentially
free-falling through the atmosphere to achieve zero gravity, but it
also means that you need to stop this motion and regain altitude by
pitching up steeply, which causes the passengers to briefly experience
2Gs. This constant up and down roller coaster motion can be
disorienting, so this is done using a plane that has no windows.
The
whole experience of free fall is extremely foreign to what
the human body is used to. It produced several unexpected and
undesirable reactions for me. At the start of each parabola, the
pilot climbs up
steeply to gain altitude. This causes the plane to greatly
lose
airspeed (it is in this period that the flyers experience the 2Gs).
When flying in an airliner, you are used to the low roar that
the
outside air produces as it rushes past the fuselage, and you do not
realize the source of this sound. After a few parabolas I
quickly
noticed that when the pilot pitched up, this roar would gradually
disappear (leading me to realize that we were losing air speed), and it
would actually get rather quiet inside the plane. So much so
that
the hissing sound of the air in the air-conditioning airvents would
start to dominate. This audible transition can be heard in
all
the video recordings that we shot, and it became an audible warning for
me for what was to follow. Once the pilot reaches the top of
the
parabola, he 'pushes over', and starts the free fall dive.
This
is just like the motion that a roller coaster does at the top of a big
descent. And, just like when I ride coasters, this phase
initially produced the same sinking feeling in my stomach.
This
was the first of the unexpected reactions, and it was quite scary and
disorienting in the first few parabolas of the first day.
The
downward arc causes your body to float up relative to the plane, and of
course, once you are off the floor and away from the walls,
there
is no way to control the motion of your body. We were warned
during the pre-flight briefings to not float over someone else's
hardware as we can cause damage when the zero gravity portion ends.
Also if the plane experiences a turbulent pocket of air, the
plane will be bumped around, and that makes you look like you are
moving around inside the plane. All these things occurred on
my
first flight, and in my quest to prevent from floating over someone
else's hardware, lead me to some hilarious bouncing and flailing on my
part. You can see a video of that below. This video
was
played at a meeting with my coworkers during flight week, and they all
had a great laugh at that.
Short video of my first flight. I tumble hilariously through
the cabin.
The feeling of floating can be quite euphoric. Note the 0.01
g on the display in front.
Another
unexpected reaction was that my eyeballs (and vision) would flicker up
and down rapidly during the transition from 2G to 0G during the initial
two parabollas. This condition is known as Nystagmus.
My
interpretation was that my body was sensing the downward accelleration
in the plane (with the sinking feeling in stomach), and it was
expecting the walls to move downward rapidly. To track the
walls,
my eyes were flickering downward and then back when they realized that
the walls were not moving. This reaction was confirmed later in 2013
when I rode 'Mission:
Space'
at the Disney Epcot theme park. In that ride, you are spun
inside
a motion simulator ride. I could tell my eyes were flickering
left-right when the G level was changing. I realized we were
being accelerated in an angular motion, and my eyeballs were
anticipating things to start spinning, and in order to track, my vision
was flicking sideways.
After a few parabolas, the above
unpleasant sensations (sinking feeling in stomach, eyes flickering)
stopped occurring, and it became a pleasant and gentle feeling to go
into zero gravity. In total, I did this 120 times, and became
quite comfortable with the transition. Due to the measures above, I was
able to prevent any symptoms of motion sickness for the flights.
By contrast, the transition into 1G was very easy, and I did
not
feel any strange symptoms.
I
have been asked quite often what it felt like to be in zero gravity.
After I got used to the transitions into zero gravity, the
feeling was very euphoric. It was similar to swimming
underwater,
and the lack of gravity produces no strange and unusual feelings in
your inner ear or anywhere else in your body. Of course,
unlike
in the water, no amount of arm and leg movement will result in being
able to push yourself through the cabin, so you need to first hold down
firmly during the transition, and then you are able to push off and
float. For most of the parabolas, we were of course working and doing
our flex hose experiments. This did not allow much time for
tumbling around. Fortunately, I had decided to put the
actuation
button for the flex hose mechanism on a hand held pendant, so I could
be anywhere to fire it. As a result, I was more free than
others
to float around and enjoy the experience. However, for the
last
few parabolas of the week, we took time to fly around, and produced
some of the best pictures of the week.
Even months later, there are weeks that Aruba leads everyone else in
those that engage with SSCO on social media.
This
week has been filled with many firsts and many amazing events.
I
will never forget it and hope to fly again in the future.
After this project, I continued my Satellite Servicing work
on Phase 2 of the
Robotic Refueling Mission.