Stories
Slash Boxes
Comments

SoylentNews is people

posted by martyb on Thursday December 02 2021, @12:50AM   Printer-friendly
from the whip-it-good! dept.

Supersonic Projectile Exceeds Engineers Dreams: The Supersonic Trebuchet:

The trebuchet is a type of catapult that was popular for use as a siege engine before gunpowder became a thing. Trebuchets use a long arm to throw projectiles farther than traditional catapults. The focus has typically been on increasing throwing distance for the size of the projectile, or vice versa. But of course you're here to read about the other thing that trebuchets can be used for: speed.

How fast is fast? How about a whip-cracking, sonic-booming speed in excess of 450 meters [~1480 feet] per second! How'd he do it? Mostly wood and rubber [bands] with some metal bits thrown in for safety's sake. [David]'s video explains in full all of the engineering that went into his trebuchet, and it's a lot less than you'd think. There's a very satisfying montage of full power trebuchet launches that make it audibly clear that the projectile being thrown is going well past the speed of sound, with a report quite similar to that of a small rifle.

Link to 15m45s YouTube video with demo near the end.


Original Submission

 
This discussion has been archived. No new comments can be posted.
Display Options Threshold/Breakthrough Mark All as Read Mark All as Unread
The Fine Print: The following comments are owned by whoever posted them. We are not responsible for them in any way.
  • (Score: 2, Informative) by Anonymous Coward on Friday December 03 2021, @08:26AM

    by Anonymous Coward on Friday December 03 2021, @08:26AM (#1201780)

    An Estes Gnome is listed as 0.29oz. An A10/3T engine is 0.29oz and produces a maximum of 13N thrust. 0.79oz=0.0224kg. This gives us ~60g peak acceleration. At 60g it takes 0.77s to reach 450m/s.

    This requires a 172m power stroke, assuming constant acceleration. That is a *very* large ballista.

    Starting Score:    0  points
    Moderation   +2  
       Interesting=1, Informative=1, Total=2
    Extra 'Informative' Modifier   0  

    Total Score:   2