Charles Wood
These are the video timings
• Ignition: 1.9 seconds
• Flameout: ~~ 5 seconds
• Splash: 17.9 seconds.
• Explosion sound: 23.5 seconds.
• Speed of sound @ 600m : ~337 m/s
My player sound delay < 0.2 seconds (sound after video)
So derived figures.
• Burn time: 3 seconds
• Flight time: 16 seconds
• Splash-to-bang: 5.6 seconds
• Calculated distance to impact: 1887m
• Average ground speed: 117 m/s
> It looks to me to be over 30 degrees, but perhaps not over 40 degrees?
Loft angle is about 30°. It's more than 23.48°, because we look at the launcher from the roof.
> What is the range effect for 30, 35, 40, 42 angles?
Loft angle is about 30°. It's more than 23.48°, because we look at the launcher from the roof.
> What is the range effect for 30, 35, 40, 42 angles?
30°
1.97 km, 17 s
45°
2.07 km, 24 s
The difference is about one hundred meters
Sasa was right - angle has little effect on the range in this range of angles.
Maximum range - 2 km. Not 3, not 4, and especially not the official 9.6 kilometers.
Discussed Video
@Charles Wood > HE is 30cm longer? Or CW 30cm shorter?
I took the engine passes through the barrel because after impact he moved out of the tail - 1980 mm length.
@Charles Wood > If you could produce a list of flight-time
But always better to check yourself - Volcano_Open Rocket_ork rse.rar (4.2 КБ)
• Flag
The Syrian arm of al Qaeda’s flag (or as Obama and the EU likes to call them, “rebels” and “freedom fighters”)
NDF
Flag on the truck is more like a flag NDF.
Oopsies - I made a tiny mistake in splash to bang. It should be exactly 6 seconds with the explosion at 23.9.
ОтветитьУдалитьThis makes the distance 337 * 6 = 2022m
I've uploaded a graphic showing various ranges centred on a known missile impact location in Zamalka
http://pbrd.co/1k3OcE8
Interestingly at least one conflict map shows 6th Tishreen and Almotahalik Aljanobi St, with perhaps a block on either side of each road insurgent free.
Wow. Beautiful rainbow!
УдалитьI'm sorry, but I am absolutely not guided in Damascus - street names do not talk nothing to me.
Out of interest, is your model using a 122mm motor and nozzle?
ОтветитьУдалитьThere is a small difference in motor length between the CW and HE variants HE is 30cm longer? Or CW 30cm shorter?
Standard GRAD
Total mass 66kg
Warhead mass 19.1 kg
Motor & nozzle mass 47kg
Propellant mass 20.45kg
Motor total impulse 39700
Motor specific impulse 1940
Motor with standard warhead 2875 mm
Motor & Nozzle 1860 mm
As we see burn time is 3 seconds so it should be easy to generate a motor file if you don't have one.
I picked up the engine with the range about 2 kilometers and flight time of about 16 seconds at an angle of 30° and a payload of 90 kg.. Then I looked at how to changed range with increasing the angle of the rocket launch - whether it will be more than a few miles away? No, range increased to 100 meters only.
УдалитьReduction under 60 kg payload produces the same effect ~ 100 meters.
If you liked my rainbow - how about an even better one?!
ОтветитьУдалитьBrown Moses is now starting to search for videos of missiles with longer flight times. He thinks that means increased range.
If you could produce a list of flight-time against range calibrated against the this video, 16 seconds, 2022m. Then I could produce a map showing time contours and how they get very close together at further range, in fact they start to get closer in for very high flight time- i.e. high launch angle.
I've tried with openrocket and my models but I think yours are better. Also, I discovered launch angle is from vertical. That is 0 degrees is straight up and 60 degrees is 30 degrees above horizontal. The model won't let you get lower than 30 degrees (higher than 60 in the input field).
Higgins has discovered flight time videos perhaps up to 24 seconds, but I think that may be the jumbo eskimo.
The video says National Defence Forces (NDF), but why is there a black al-Qaeda flag on the truck?
ОтветитьУдалить