Where did Taepodong-2 land? (ii)

BBC has this chart, showing the Long range missile (TPD-2) landed about 400 km east of Korean coast (launch site musidan-ri).

...and wiki has a similar one


According to wiki, Taepodong-2's full speed is around 8-9km/s, and that the missile landed about 40 seconds after it was launched.

Let's do some simple maths, on the maximum distance the missile travelled. Let's assume the missile reached top speed before it landed (more likely it didn't. it would have started burning the second stage if it did, plus acceleration stopped a few seconds before it reached water surface), and let's assume only the horizontal component of the velocity (the range would be smaller for parabolic trajectory, because the horizontal component is less than 8-9km/s), then the upper bound of the distance traveled is:

• average speed x 40 sec
• = (0+8.5)/2 x 40 = 170 km
  

In reality the distance the missile traveled was at most 50-100km from the launch site. i.e. closer to NK than Russia and it should be to the west end of BBC's green ellipse. More likely it probably landed less than 10 km away from the launch pad, as most of the initial thrust was given to vertical accelerarion. BBC's red ellipse seems to be placed totally wrong.

Update: Globalsecurity confirms my hypothesis here. It also showed that the S Korean claim of 499km is incorrect and "appears to be mixing the other missile flight data observations". In fact, Globalsecurity's estime is only 1.4km, confirming my suspection that a lot of the energy was given to the vertical thrust upward.

• "[Vick] is reasonably certain it was not aimed at the United States at a much higher inclination as discussed below. It ultimately impacted near the launch site infrastructure just off shore perhaps about 1.4 kilometers from the pad with perhaps 4.4 km altitude gained before collapsing into the Sea of Japan"

Update: An anon commentator (presumably a rocket scientist), posted a table of typical 2-stage rocket trajectory below. Given the known size/weight and nature of the rocket's fuel/propelling mechanism, the actual trajectory should be within the order of magnitude of the 'typical trajectory (i.e. at most a factor of 3-5 away). Vick's estimate was confirmed
"TIME___ ALT___ RNGE ___VEL.
(SEC)___ (KM)____ (KM) ___(KM/SEC)
40.0 ____4.3 _____ 1.2 _____ 0.25
45.0 ____ 5.6 _____ 1.7 _____ 0.29"

4.4km above sea level is like the peak of the highest mountain in Europe/US.
1.4km is slightly less than a mile or some 5 football fields away, just barely into the ocean
0.26km/sec=260m/s = 936km/hr = 585mph, which is sub-sonic and slightly higher than the cruising speed of a 747 airliner

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