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The sixth annual
"Fire in the Sky" (FITS) launch was held in the Pacific Northwest
over Memorial Day weekend near the small town of
Mansfield Washington. It was hosted by the
Washington Aerospace Club (WAC). This year the three day
launch was on May 27-29, 2006 and was the largest FITS launch to
date. It was very well attended with flyers coming from all
over the Northwest. There were a total of 405 flights
with nine of those being on M-motors! |
I (Vern) only flew three
rockets at this event but all three were on M-motors.
Angelfire successfully flew on an
Aerotech M1419
to almost exactly 10,000 feet. My
GPS radio downlink
electronics were on-board for this flight and the data from it along
with lots of photos from the flight are further down on this page.
I also launched Starfire
on an AMW M3000
"Super Tiger" motor along with six out-board J-motors that were
supposed to be air-started in two sequential groups after main motor burn
out. Unfortunately, the J-motors never ignited because the timer got
reset during main motor boost. The cause of the reset is still being
investigated. Still, it was a nice flight to 4,867 feet with a
successful recovery. Starfire carried an on-board camcorder as well as two
digital still cameras. The video and the photos from the flight are
presented below.
I also launched
Wildfire on an
Aerotech M1297
to 6,081 feet. The flight was perfect with Wildfire carrying a
video TV transmitter that sent back live
video during the flight. It was fun watching the flight and the
recovery from the ground but then at the same time watching the flight and
the recovery on the video monitor from the point of view of the rocket
itself.
All in all, I must say,
this was a great event. It was well organized, safely run, with
great flights and lots of great people to meet. A special thanks
goes out to the launch director Jim Pommert for his tireless efforts to
make this launch such a huge success. And a big thank you to ALL the
Washington Aerospace club members that volunteered and helped run the
event. It really was exceptional! I am already
looking forward to next year!
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| Click on any photo on
this page to see a larger version of it. |
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Photo by Vern Knowles
This view is looking back
towards the crowd from the high power pads at FITS 2006. It was
taken on Saturday at about 5:00pm.
Click here to see a large high resolution image.
(1.5 MB file.)
Click here to see a smaller low resolution image.
(200 KB file.)
NOTE: Some web browsers will automatically scale this
panorama image to fit the width of your computer window. If yours
does that, then be sure to expand the image to full size. You should
be able to pan across the large image and get a good look at the whole
flight line. |
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Photo by Tsolo T.
Tsolo from RocketShots! © 2006 |
FITS is the only launch I
have ever attended that has bleacher seats available for spectators!
The town's mayor (Tom Snell) brought these bleachers in from a nearby
school. Tom is the large man in the front row in the blue
shirt. In fact, the whole town of Mansfield is very
supportive of this launch. There was even a small banquet held at
the nearby school on Saturday evening. |
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This is an aerial view of
the FITS launch site taken Monday about midday with a camera on-board
Starfire. Monday was the last day of the launch and many
people had already left by this time. The parking and camping area
was full on Saturday but was only about half-full by the time this photo
was taken on Monday.
The launch pads were setup
on the dirt race track and the away cells were out beyond that. |
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It is not possible to fly
large rockets without a lot of help from friends. In this
photo, Todd Bright (green jacket), Ray Stoner (kneeling), Kent Newman
(holding nosecone) and Bob Yanecek (supervising) helped me load Angelfire
onto the launch pad. In fact, these guys even carried the
rocket as well as all my cameras, tripods, ladder and tools out to the
launch pad for me! I had hurt my back on Friday when I arrived
at the site by trying to lift the hitch on my trailer while parking it.
A very dumb thing to do, but I did it and I learned my lesson. At
any rate, everyone at FITS was so helpful that I was still able to pull
off the three launches I had planned, even with a bad back. Thank you
guys!
Angelfire was my first flight at FITS.
It was flown on Sunday morning in perfect weather conditions on an
Aerotech M1419. This was the fifth flight for Angelfire.
Click here to see photos
from the previous flights. For this flight I had the
privilege and the honor of being the very first to launch from a brand new
launch pad supplied by Bill Earl. Bill was not able to attend FITS
this year but he sent his pad on anyway so that it would be available for
use by others. Wow, thanks Bill! It is certainly a very nice
pad! |
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Photo by Kent Newman |
Photo by Vern Knowles |
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Angelfire
GPS Flight Data |
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Angelfire carried a GPS
receiver and a radio transmitter in the nosecone. The transmitter
was sending the GPS coordinates as well as speed and altitude data to a
receiver on the ground. This data was then recorded in a small hand
held computer for later analysis.
Click here to see more
details about this system. After the flight, this data was
loaded into the Google
Earth program so that the trajectory could be seen in a three
dimensional view of the launch area. A view looking due north is
shown below. The trajectory is shown in yellow and the landing location is
shown by the yellow "X" on the ground. The GPS receiver captured
good data all the up and during most of the descent, but unfortunately, it
lost lock when Angelfire had descended to about 2000 feet above the
ground. This means the trajectory in this photo ends about
2000 feet above the ground. An "X" was added to the photo to show
where Angelfire eventually touched down. |
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Altitude reported by GPS
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Velocity reported by GPS
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Click on the charts above
to see the altitude and velocity data reported by the GPS. Each
point in the plot represents one GPS reading. The GPS updates at
five times per second. (Readings are spaced apart by 200ms.) The
peak altitude was 10,021 feet above the ground and the data stops at about
110 seconds into the flight when there was still 2000 feet to go.
The peak velocity was 542 mph. The descent velocity on drogue chute
was about 65 to 70 mph.
The velocity data plotted
above is just the "up" component of velocity. The GPS also reports
the "north" and the "east" components of velocity to give a true 3D
velocity vector. To see plots of all of the GPS data click on
the link below.
Click here to view Angelfire
GPS data plots in PDF format
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Angelfire
Altimeter Flight Data |
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Angelfire also carried an
ARTS
recording altimeter. This altimeter uses both an accelerometer
and a barometric pressure sensor to collect flight data. Six pages of analysis of
the data from the ARTS altimeter is presented below. You
can click on each page individually to see an image of it, or you can get
all six pages at once in a higher resolution PDF document.
Click here to view Angelfire Flight Data in PDF format |
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Page 1 |
Page 2 |
Page 3 |
Page 4 |
Page 5 |
Page 6 |
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Specific events that can be
identified have been highlighted on these plots.
Maximum acceleration was
5.29 G's. Peak velocity was 771 ft/sec (526 mph). Angelfire
reached apogee in 26.7 seconds. After that, it descended on the
drogue chute for 1.5 minutes at an average of 100 ft/sec and then deployed
the main with 982 feet to go.
It descended on the main chute for 38.7seconds at an average of 24.4
ft/sec. Total flight time was 2.6 minutes.
Angelfire uses two
MissileWorks altimeters to deploy the drogue and the main parachute.
These two altimeters reported the peak altitude to be 10,435 and 10,808 feet.
As seen above the ARTS
altimeter reported the peak altitude as 11,109 feet based on the
accelerometer and 9,965 feet based on the pressure sensor. The GPS
reported the peak at 10,021 feet. Averaging all of these altitudes
together gives 10,468 feet and all the readings are within +6% to -5% of
this value.
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Page 1 |
Page 2 (top) |
Page 2 (bottom) |
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Click on each page icon
above for a better view. They show the altitude and velocity data
from the GPS and the ARTS plotted on the same charts. The GPS
altitude data matches very closely to the ARTS barometric pressure sensor
data during the whole flight. However, there are some interesting
differences in the velocity curves. The GPS has glitches in the
velocity readings during the boost phase and the accelerometer has drift
problems after apogee. Both effects are normal and are expected.
To see these plots in PDF format, click on the link below.
Click here to view flight data comparison plots in PDF format
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The flight I had planned
for Starfire at FITS 2006 was more
ambitious than any previous flight it has made. The plan was to
liftoff using an
AMW M3000
"Super Tiger" motor and then ignite four J350 outboards at five
seconds and then ignite two J570 motors at eight seconds. This puts
the total impulse at 12,290 NS which is in the N class and should have
pushed Starfire to nearly 12,000 feet. This would have been the
highest flight yet for it. Starfire was also carrying a
mini-DV camcorder in the lower payload bay and a module with two digital
still cameras in the upper payload bay.
Unfortunately, none of the
J-motors ever lit because the onboard timer got reset during the main
motor burn. The cause of the reset is still being investigated.
The timer is a
MissileWorks PET2 unit and it was beeping out the correct
3-beep sequence prior to launch. However, as can be heard in the onboard
video, the beeping changed during the main motor burn to a pattern that
indicates the timer had been reset. The timer was configured to
start timing when a break wire showed loss of continuity. This
indicated liftoff. That part worked fine, but when the timer got
reset AFTER the break wire was already open, it went into a "safe mode" to
avoid doing anything harmful. The result was that Starfire coasted
on up to 4,867 feet and then deployed the chutes and cameras. The
video and the still photos from the flight are presented below.
Since this flight was in
the "N" impulse range and it involved more than one motor, it was a
"complex N launch." The safe distance requirements for this type of
flight is 1500 feet. At the FITS site, the most convenient way to
setup that far away from the crowd is to go out onto a gravel side road.
This resulted in the launch pad being setup about 3000 feet line-of-sight
from the flight line. Any closer and visibility from the
flight line would have been obstructed by a nearby hill. |
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Photo by Todd Bright |
The last J350 gets
installed. |
Photo by Tsolo T.
Tsolo from RocketShots! © 2006 |
This is the business end of
Starfire with a central M3000 and six J-motor out-boards. All six
outboards are slightly recessed but have a metal spacer ring with a slot
in it to allow the igniter wires to pass through. The metal spacer
rings are held in place here with masking tape until the final aft motor
plate is installed. Some red modeling clay was also used to seal up the
ends of the igniter wire conduit tubes that lead back to the timer
electronics. The thin blue break wire can be seen on the left side.
It will be tied to the launch pad and then at liftoff when it breaks, it
signals the timer to begin the timing sequence. |
Photo by Tsolo T.
Tsolo from RocketShots! © 2006 |
Photo by Tsolo T.
Tsolo from RocketShots! © 2006
These two photos show the motor retainer
plate being put into place. It is held in place with three machine
screws extending into T-nuts inside the aft bulkhead.
Aluminum foil tape is used to seal up all of
the air-starts to protect all of the igniter wires from heat and
potential "blow back" of main motor exhaust from the blast deflector on
the launch pad. When the out-board motors ignite, they will easily
rupture the thin aluminum foil tape. |
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Starfire carried a camera
module in the forward payload bay. The left photo below shows me
(Vern)
installing the camera module while Kent Newman holds the body tube.
After the camera module goes in, the nosecone is put into place. The
camera module is dumped out at apogee and the digital cameras begin taking
lots of aerial photos during the ride down on the parachute.
Click here to see information and
photos about the camera module itself. |
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It was finally time to put
Starfire onto the launch pad and get it vertical. For this job I had help from
Ray Stoner, Todd Bright and Marty Weiser. Ray and Marty were also
kind enough to park down at the far end of the gravel road and make sure
no one approached the launch pad from that direction. The launch of
Starfire was held up for quite some time due to a sailplane glider that
was loitering in the area. Eventually it departed the area and we
were go for launch! |
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Photo by Todd Bright |
Photo by Vern Knowles |
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Photo by Tsolo T.
Tsolo from RocketShots! © 2006 |
Toward the end of the main
motor burn there was a very loud "pop" that came from Starfire. The photo
at the left shows one of the motor grain casting liners falling away from
Starfire. It had momentarily plugged the nozzle but was expelled as
the internal pressure increased. The exhaust smoke trail also shows
signs the motor was plugged for an instant. Fortunately there was no
damage caused by this. Click on the photo at the left for a better
look at it! |
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Below are some of the
photos taken by the camcorder and the digital still cameras onboard
Starfire. Click on each one for a better view! |
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PLEASE NOTE: To
view these videos it is probably best to right-click on the link and then select "Save Target As ..." so that it will store the movie file on
your computer. You can then open the file and view it after it is
completely downloaded. Doing so will allow it to play cleanly and
continuously without all the starts and stops caused by internet traffic. |
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Wildfire is 9 feet long,
5.5 inches in diameter and carries a CCD video camera and a 1.2 GHz FM
amateur TV transmitter that transmits live video back to the ground during
flight. The video is also overlaid with textual GPS information showing
altitude, speed and location. More
details about this system can be found here.
Wildfire was launched on
Sunday afternoon at FITS on what would be its 19th flight.
The M1297 motor boosted Wildfire straight up reaching 6,081 feet and
deployment occurred right at apogee. Everything about the flight went perfectly, except that there were two technical problems with the
TV video. One was that the on-board GPS system never locked-up
properly and therefore did not provide any information to overlay onto
the video screen. The second problem was even more disappointing
and was not discovered until later that evening. The video
displayed on the TV monitor during the flight was in full vivid color.
However, for some reason the VCR that was used to record the video only
recorded it in black and white. Nevertheless, it was still
fun watching the flight and the recovery from the ground but then at the
same time also watching the flight and the recovery on the video monitor
from the point of view of the rocket itself.
Despite the technical
problems with the video, the flight itself was spectacular and Wildfire
was recovered with no damage so it can easily fly again. |
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Wildfire was launched from
the same 500 foot "M" pad as was Angelfire earlier that morning. I
would like to thank Jeff Moore for his help with the final prep of
Wildfire, for helping to set it up on the launch pad and for manning the
TV receiver antenna to keep it pointed at Wildfire during the entire
flight. I would also like to thank Todd Bright for his help
recovering Wildfire. |
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Photo by Vern Knowles |
Rick Clapp was camping next
to me at FITS and was a huge help to me many times by providing assistance
in my time of need after I had hurt my back. Thank you Rick, I
really appreciate it!
Here Rick is installing the
igniter into his PML Endeavour just before launching it on a K550. It was
a great flight, but as you can see by the clouds in the background it was
also threatening to rain. Before Rick could recover the Endeavour it
did indeed rain for a while. Rick returned soaked and had to change
clothes to get dry. Fortunately, the rocket survived the rain.
As usual Rick was taking
lots and lots of photos at FITS in preparation for submitting them to
Extreme Rocketry
magazine. I can't wait for that issue, it should be great! |
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Photo by Vern Knowles |
Todd Bright lives in
Ketchikan Alaska. He flew down to FITS so that he could get his TRA
level-2 certification. After he took the L2 written test, I
told him that he didn't get any questions wrong and he said "I've come too
far to miss any!"
Todd launched his beautiful
Nike Smoke on a J315 Redline motor for a perfect flight. His L2
certification was a success! Congratulations Todd!
Todd was also a big help to
me on every one of my flights. He helped with setup at the launch
pads as well as with recovery. Todd also provided some of the photos
and a video that are shown on this page. Thank you Todd! |
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Photo by Todd Bright |
This is how Todd flies
rockets back in Alaska. He built this floating launch pad that allows
him to fly on the water and avoid all the trees. His rockets are
designed to float and recovery is by boat. The landings may
be wet, but at least there are no worries about hitting the ground too
hard! |
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