Date: 31st December 2006
7:15 - 9:15 am.
Denzil Joyce Oval. (launch site #4)
Where exactly is that? Click the
above link to see a Google Earth
place mark. What is
Heavy cloud cover, occasional shower, very
light breeze - picking up towards the later
part of the launch day.
||This is a newer rocket made out of
three 1.25L bottles. Parachute
deployment is achieved using the
Rocket is typically filled with 1.1
liters of water. The nosecone was
slightly modified from the last day
where it was deploying too early.
||This is an older rocket designed to
carry a video camera and a flight
computer. On this day, it was flown
with the camera and the flight computer.
||An old good performing rocket with a ring fin
||An old rocket reinforced with
glass fiber tape for this launch event.
||A very good older rocket flown in the
same configuration as the last time
it was flown.
Team Members at
PK, GK, DK, Paul K and John K.
of launches: 16
This was a good day with plenty of
launches, a couple of spectacular parachute
failures, and a couple of new personal
records. My cousin Daniel visiting this
month also joined the team and assisted with
all manner of tasks. He also took plenty of
pictures and video too.
Flight Day Events
- Frankovka III was first off the pad on
a video mission. The video was very good
and even shows where it landed in the low
- On the next flight Frankovka III had a
good deploy just after apogee, but we
watched the parachute canopy just flapping
without opening ... all the way to the
ground. We saw a similar problem last
week, but the parachute opened after a
couple of seconds. On this occasion the
rocket took a pretty heavy hit and
destroyed the entire nosecone and payload
section. Luckily the FC survived with only
minor damage to the power switch, but
otherwise powered up and worked just fine.
It was just as well that the camera was
not on this flight. Individually the
release mechanism components also survived
well, so we will just have to re-create a
new housing for them. We will need to have
a careful look at the parachute packing
procedure to try to minimise this risk.
The rocket was not in a state where we
could fix it in the field.
The upper pressurised bottle was also
quite badly crushed, so it will be
replaced. We have been wanting to do a
rebuild of this rocket, so it gives us a
good opportunity to do that. Replacing
bottles is comparatively easy when you use
Robinson style coupling as opposed to
- J4 perfomed very well on the day, but
suffered what looked like a similar fate
to Frankovka III with the parachute
deploying but not opening. When we
recovered the rocket, we found that the
nose cone tether had ripped off from the
rocket on the way up and the end of the
tether somehow managed to wrap itself
around the main chute lines just below the
canopy and so the cannopy didn't open.
(see photo on left).
- Just for laughs we decided to launch
an older 1.5L rocket (Clifford) to compare
the difference in takeoff with the heavier
rockets. Clifford flew a perfect flight
profile and deployed its chute right at
apogee. It then proceeded to drift back to
earth very slowly. I suspect that the wind
direction and the range topology had
something to do with it. The wind blew in
the other direction to the prevailing
winds, and I believe the row of trees and
bushes caused the wind to move upward over
them, and as the rocket passed over the
trees it seemed to hang in the air longer.
Although we didn't see the exact moment
when the rocket hit the ground, we were
able to calculate the 2 seconds of flight
to the ground behind the trees based on
the descent rate at the time just before
dissapearing behind the trees and the
height of the trees. The ground behind the
trees is level with the launch pad.
Regardless of the exact time, we have
considerably broken our previous personal
record flight time. The new time was
48.2 seconds. (the previous record was
31.5 seconds set by OO with twin chutes.)
It is good to see that you do not have to
build sophisticated rockets to achieve
good performance. Although Clifford
doesn't go as high as the bigger rockets
it is light weight and has a resonably
- We also launched our smallest rocket -
John John - for the kids, but on
subsequent flights we decided to see how
far we could push it, so we increased the
pressure and also added a wrap of the
glass fiber reinforced Scotch strapping
tape. We slowly increased the pressure all
the way up to 185 psi. This was also our
own new personal record for the highest
launch pressure. For this test we made
sure everyone was well clear of the rocket
when it was being filled.
You could certainly see the effect of the
higher pressure on the takeoff speed and
hear the sound it makes. We are not sure
how high it goes, but a flight time of 7.2
seconds was achieved. The rocket is very
light and has a medium density foam
nosecone. It doesn't use any parachute
deployment or backsliding technique for
- We dusted off our older rocket OO, but
when we launched it it spiraled quite
significantly. When it landed we noticed
that the fin supports had sagged to one
side quite significantly. This was caused
by the rocket being stored vertically
standing on its fins. This was our own
fault as we didn't check the fin
alignment prior to launch.
||Flown with a camera,
and the computer was set for 4.75
second deploy. Used 9mm nozzle.
||Flown without a
camera, computer set for 4.75
seconds. Parachute deployed when
expected, but canopy did not open
and rocket crashed heavily. Nosecone
and payload section destroyed.
||This was an
excellent flight with a good deploy
and landed well. Used 7mm nozzle.
||Again a very good
straight flight. with a good deploy.
||We used the 7mm
nozzle with this rocket for the
first time, it spiraled quite a bit
on the way up. The parachute opened
||We used a 9mm nozzle
this time. The flight was very
straight and very high again. Good
deploy a nice landing.
||9mm nozzle. Good
flight but the parachute deployed
early, this caused the nosecone
tether to rip off from the rocket
but tied itself around the main
chute lines. Canopy did not open and
||Good flight, 9mm
nozzle. The wind started picking up.
||Good normal flight.
||Good flight. Highest
launch pressure to date.
||Great flight. Again
highest pressure to date.
||Perfect flight, used
7 mm nozzle. This currently stands
as our longest duration flight of
48.2 seconds. The parachute deployed
right at apogee.
||Good flight, but the
parachute deployed early. 7mm
||OK flight, but the
rocket spiraled a little, but the
nosecone didn't come off. The rocket
hit the ground pretty hard, but no
significant damage was done.
||Highest pressure to
date one more time. Rocket used a 7mm nozzle and the
takeoff speed difference was
noticeable. We used about 200ml of
||Used 7mm nozzle and
400ml of water, the takeoff was a
tad slower and the rocket did not go