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Recently, a video was found in which the flight
path of Paektusan launch vehicle can be seen on a display. An analysis contradicts
all previously published or estimated data. The "satellite" fell back after
just 530 seconds. The second and third stage of the launcher did not work,
so that only a top speed of 3055 m/s was achieved. The noted times are the
automatic separation mechanisms.
An
instability can be seen
at 19 seconds.
The determined final speed of the first stage of about 3000m/s and its burnout
after 94 sec in the altitude of nearly 500 km are cannot be explained.
Presumably it is the suborbital test-launch
of the Paektusan-0 with no fuel in the upper stages. On the curve of the speed
of the first stage (burnout at +94 sec) a kink can be seen after about 19
sec, which is perhaps due to functional disorder. The speed curve hardly increases
after 94 sec because the second stage do not work (no fuel). Nevertheless,
the altitude continues to rise because the iniciated impulse by the first
stage still has a significant effect on the slight rest of the rocket. Cold-gas
control engines of the second stage could have been used for a small thrust.
What is strange is the continual increase in the speed of the "satellite"
which may have been something else.
.Here my analysis:
Test of the
terminal
velocity (dV)
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vac Isp (sec)
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=Ns/kg
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Mf (kg)
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Me (kg)
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Mf/Me
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ln Mf/Me
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Isp * ln (Mf/Me)
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1st
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268.5
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2633
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14,224
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3,073
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4,629
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1,53236
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4,035
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2st
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-
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-
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954
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954
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1.000
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0.00000
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0
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3nd
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-
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-
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30
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30
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1.000
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0.00000
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0
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dV Total*
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4,035 [m/sec]
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* dV
(vacuum); without losses of 25% of velocity
Therefore is the real dV nearby
3,026
m/sec for 20kg
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Flight Profile
Paektusan-1
North Korea reported the launch
of its first satellite as follows:
The rocket was launched in the direction of 86 degrees put the satellite into
orbit four minutes 53 seconds. The first stage was separated from the rocket
95 seconds after the launch The second stage opened the capsule in 144 seconds,
separated itself from the rocket in 266 seconds The third stage put the satellite
into orbit 27 seconds after the separation of the second stage. The satellite
is running along the oval orbit 218.8 km in the nearest distance from the
earth and 6,978.2 km in the farthest distance.
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Lift-off Vehicle
= 0 sec
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Paektusan-1
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Burnout
first stage
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+ 94
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Separation
first stage
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+ 95
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Coast
phase
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+ 95 ... 140
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Ignition
second stage
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+ 140
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Separation
fairing
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+ 144
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Burnout
second stage
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+ 215
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Separation
second stage
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+ 215
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Coast
phase
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+ 215 ... 266
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Ignition
third stage
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+ 266
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Burnout
third stage
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+ 293
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Separation spacecraft
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+ 293
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Estimation of the
terminal velocity (dV)
[dV = Isp [Ns/kg] * ln (Mf/Me)]
1. -- Mf - first stage:
Total mass of the launcher
Me - first stage: Empty mass of the first
stage +total mass of the second stage +fairing +payload
2. -- Mf - second stage: Total mass of the second stage +fairing
+payload
Me - second stage: Empty mass of the
second stage +fairing +payload
3. -- Mf - second stage: Total mass of the third stage with payload
Me - second stage: Empty mass of the
third stage with payload
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Flight path
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Peaktusan-1
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vac Isp (sec)
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=Ns/kg
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Mf (kg)
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Me (kg)
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Mf/Me
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ln Mf/Me
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Isp * ln (Mf/Me)
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1st
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268.5
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2633
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19,169
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8,018
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2.391
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0,87156
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2,295
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2st
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258
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2530
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5,900
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1,044
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.5.653
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1.73215
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4,382
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3nd
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236
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2314
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639
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12
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5.338
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1,67480
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3,875
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dV Total*
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10,553 [m/sec]
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*
dV (vacuum); without losses of 25% of velocity
Therefore is the real dV nearby
7,915
m/sec for 20kg
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