Is this determinable? (Size of this Russian patrol boat)

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Discussion Overview

The discussion centers on the possibility of determining the size of a Russian patrol boat using the physics of shrapnel arcs and other visual cues from video footage of an explosion. Participants explore the feasibility of using ballistics analysis and scaling cues to estimate the boat's dimensions, while also considering the limitations of the available data.

Discussion Character

  • Exploratory
  • Technical explanation
  • Debate/contested

Main Points Raised

  • Some participants propose that the physics of shrapnel arcs could provide information about the boat's length by analyzing the distance the shrapnel travels.
  • Others mention that scaling cues, such as the behavior of particles and features on the boats, could help estimate size, though they express uncertainty about the reliability of these cues.
  • A participant questions whether the focus is on analyzing ballistics or simply determining the boat's size, suggesting that the presence of an outboard motor might be a significant clue.
  • Some participants express skepticism about the accuracy of any analysis, citing numerous uncertainties when relying solely on video footage without additional context.
  • One participant notes that a forensic scientist might be able to estimate the boat's size from the explosion, but questions the accuracy and precision of such an estimate.

Areas of Agreement / Disagreement

Participants do not reach a consensus on the effectiveness of using shrapnel arcs or visual cues to determine the boat's size. Multiple competing views remain regarding the reliability of the analysis and the potential for accurate estimations.

Contextual Notes

The discussion highlights limitations such as the dependence on visual cues from video footage, the uncertainties inherent in ballistics analysis, and the lack of contextual information that could aid in size determination.

thetexan
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Is it possible to determine the length of the boat by using the physics of the shrapnel arcs?

Can the traces of the arcs be used to determine the distance the shrapnel travels and then be send to determine the boat length.

Tex
 
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There are definitely scaling cues. I'm not sure how good they are.
The bright cinder-like "particles" give a clue to their density as they rise and quickly slow. Then their downward acceleration until they reach terminal velocity happens very quickly, suggesting the scale.
Normally, the blast itself would give clues. But the optics are so bad that its hard to separate internal reflections in the optics from atmospheric effects.

The biggest scale cues are features on the boats and the way that the second boat is maneuvering.
 
Is this physics exercise in analyzing ballistics? Or are you more interested in the size of the boat?

Because, frankly the most obvious clue to judging scale is the fact that the boat seems to have an outboard.

In fact:
1651712598260.png

1651712551717.png

"China 12.7m High Speed Fisheries Patrol Gun Boat for Sale Russian"
 
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I doubt that any such analysis will be accurate enough to disprove the published reports that these are Raptor-class boats, 16.9 meters long. There are just too many uncertainties involved when just working with the videos and no context.
 
Nugatory said:
I doubt that any such analysis will be accurate enough to disprove the published reports that these are Raptor-class boats, 16.9 meters long. There are just too many uncertainties involved when just working with the videos and no context.
I saw pix of these raptor class boats, and disqualified them immediately.

Look at the windscreen:
1651714065579.png

It is sloped inward at the bottom, similar to many ocean-going vessels.

The one in the video seems to have an outward sloped windscreen (see post 3).

It just doesn't seem to match.
1651714918829.png
 
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My interest is in whether there is enough info in the video from the explosion to determine is size.

If a forensic scientist tried to determine the size of the boat just using the explosion could he, knowing nothing else?

Tex
 
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thetexan said:
If a forensic scientist tried to determine the size of the boat just using the explosion could he, knowing nothing else?
Probably. But to what accuracy or precision I can't say. You're probably far better off just looking at the shape and relative sizes of the boats components and the way it moves through the water.
 

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