Here is a post that was on the Ukraine thread. I didn't want to derail that thread. Perhaps this is more suitable place for it.
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Originally Posted by
WideScreen
Forces, etc: Nop, just a general judgment of proportions, etc.
Yep, I noticed the eject around the 13-second mark. However, the other shootings don't show that as well (despite having a front view of the presumed ejection location).
Did you notice the trajectory of the ejected part? It doesn't go down, but just flies away at a 30 degrees (or something) angle with the vertical and doesn't seem to follow gravity. Let alone, a bullet casing would be that small, it should disappear quite fast from being visible, which doesn't happen.
Also, the video does have 2 camera angles, where the location presumably ejecting the bullet casing in the second part, is visible in the first scene, but no visible signs of an ejection location there (let alone the ejections, let alone a bullet magazine).
Looking at the terrain, it doesn't really look like Ukraine territory, more a desert-like environment in Africa, with the oddity of "green" trees and large sandy/dried-out surfaces, IE the type of landscape artificially created in games/FS.
As you raise, it would be a beautiful thing, when it's reality, though the promo video certainly raises questions, about whether this thing is real or just another artistic/AI "artifact". Things just don't add up.
Does anybody have a name of this thingy, that can be used to search for more info?
Std rifle weights...
- For a .223, 55gr, 4.34 Nm
- 7.62x39, 125gr, 9.36 Nm
- .50 BMG, 647 gr, 94.9 Nm
A .17 Hornet or .22WMR with fragmenting bullets would do the task against a drone with negligible recoil, and are extraordinarily accurate within 50 mtrs.
I too have my doubts as to how real this particular video is. I too could not understand why there is only one ejection. But I am expecting something like this to come to market at some time, and I seem to recall video of something similar from a couple of years back. There are aspects of what is in the video that make me think that whilst it may be a rendered CAD video model, nonetheless it may originate in something that has once had some genuine engineering roots. Or maybe not.
Anyhows, let us say that is a drone firing a 7.62x39mm round. So a 10 gram projectile doing 640 metres/sec. So 2,048 Joules kinetic energy.
On the drone side here are a couple of representative things.
Somewhat similar copter-stle to the drone in the imagery. Slow, so not so good for air-to-air against anything fast but maybe it is enough as a platform to take out the other side's shorter range quadcopter drones.
10kg payload, 29 kg MTOW, 18 m/sec speed. (So 4,698 Joules kinetic energy.)
https://www.jouav.com/products/ph-25.html
Not similar as utilises wing-borne flight, but may be better suited to longer range intercepts.
20kg payload, 100kg MTOW, 100 kmh (27m/sec) speed. So 36,450 Joules kinetic energy.
https://www.jouav.com/products/cw-80e.html
I really don't know much about recoil mechanisms and their capabilities. Some of you clearly are into that sort of thing. But a 100kg drone launch platform is not so different than a 100kg human in ratio terms, at least for the first shot. Being able to restabilise the launch platform for subsequent shots (and target tracking etc) will obviously also depend on the control authority of the drone's flying/propulsion surfaces. Not something I have time for right now, but if any of you do then it will be interesting to read what you think, and to learn from you.
A couple of references for anyone interested in doing more numbers
https://en.wikipedia.org/wiki/Free_recoil
https://en.wikipedia.org/wiki/Physics_of_firearms
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Following that I looked around a bit more and came across this discussion
https://www.eng-tips.com/viewthread.cfm?qid=492130
This suggests an approx 10 ms duration of the bullet leaving the barrel
If you have a look at this
https://www.omnicalculator.com/physics/recoil-energy
and plug in the AKM cw 7.62 x 39 it gives a 7.18J recoil energy for a 3.75kg firearm.
So overall I suspect these are eminently doable devices.