62" shell

Discussion in 'Professional Fireworks' started by Locky Smith, Feb 4, 2019.

  1. Arthur

    Arthur Pro Firer/Crew

    I only wish my maths was up to calculating the force needed to raise a 60" shell to whatever the launch velocity needed is in the length of a mortar tube. and calculating the rise height available with gravitational and air friction deceleration.

    On one trip to Royal Gunpowder Mills (Waltham Abbey) there was some replica BP grains from WW1 large naval guns. Those grains were 14mm AF hexagons about 12mm thick. This was to reduce the muzzle thickness by distributing the thrust as the shell (iron) moved along the barrel.
     
  2. Pyro Ed

    Pyro Ed Pro Firer/Crew

    This is quite simple maths, if you make approximations of air resistance.
     
  3. Maybe a silly question but would it actually have to be fired from a tube? There are various ways that something fairly big and heavy could reach a mile in the air and i'm assuming it would still count towards a record as long as it bursts properly.

    Maybe dropping it from a plane would be a bit cost prohibitive and i'm sure hse in whatever country it was would have concerns about that but it would probably have a far better success rate.
     
  4. Da Main Mouse

    Da Main Mouse Supports UKFR

    I was thinking like someone else mentioned a huuuge air cannon would be relatively simple to make....
     
  5. hofnerite

    hofnerite UKFR Stash Photo 2018 Winner! Supports UKFR

    Possible but that would multiply the costs by god knows how much. That shell weighs a tonne and is *allegedly* 7 foot in diameter. Imagine the air pressure you'd need to harness and release in one go to get that a couple of kilometres in the sky. :eek:
     
    Da Main Mouse likes this.
  6. blackbat

    blackbat Pro Firer/Crew Supports UKFR

    ?? 62" is just over 5 feet.
     
    Da Main Mouse likes this.
  7. hofnerite

    hofnerite UKFR Stash Photo 2018 Winner! Supports UKFR

    aah, yes.. I was thinking in man-inches. :oops:
     
    fozzboy and Da Main Mouse like this.
  8. Da Main Mouse

    Da Main Mouse Supports UKFR

    There are multiple ways to create a movement of air on that scale.
    Expensive yes, but more than likely also reusable, meaning repeated and accuarte testing and data. Not to mention adjustments on the fly as such.

    This in turn could lead to testing of pressures reached etc leading to catalogue of information compared to working up with expensive shells and burst each time.

    I mean you need a rocket range to test it like but we are talking hypothetically here...

    Then when you know safe parameters you can use live stuff?

    There are also numerous ways to change tje flow of gases.
    So assuming we have a safe acceleration speed and known end trajectory through testing we can look at how to apply that to the shell.

    Unless of course the rules state the lift charge must be attached to the shell, in which case this is all pants....:D
     
    hofnerite likes this.
  9. hofnerite

    hofnerite UKFR Stash Photo 2018 Winner! Supports UKFR

    I always thought these big shell attempts were based on beating the previous weight. If it's size alone then it would be easy to make a light shell with a smaller burst charge in the middle.
    :quasi:
     
    Da Main Mouse likes this.
  10. elmo

    elmo Pro Firer/Crew

    And lets face facts, the noise of the lift on any big shell is often better than the burst itself:D
     
  11. Da Main Mouse

    Da Main Mouse Supports UKFR

    Im sure the sound of anything travelling at the speed required to get that weight up would be immense. Regardless of air, water or explosives. It is afterall the release of said pressure and projectile that makes the noise?

    We may have to do some rule studies lol
     
  12. PyroAsh

    PyroAsh Pro Firer/Crew Supports UKFR

  13. Jon Coles

    Jon Coles Pro Firer/Crew Supports UKFR

  14. RocketRev

    RocketRev Moderator Supports UKFR

    The commentary in that video is not safe for work in a vicarage office!!! :eek::)
     
    Da Main Mouse, PyroAsh and hofnerite like this.
  15. AtomFireworks

    AtomFireworks Pro Firer/Crew

    I could be wrong on this occasion, however when I considered a Guiness record attempt at the biggest catherine wheel in the detail it stated for it to be considered a record the wheel had to be a scaled up version of an existing available cathrine wheel, using the same same materials and design. I believe this is why they have to stick to a traditional concept in the record attempt.

    Jay
     
    maxywell and Da Main Mouse like this.
  16. Da Main Mouse

    Da Main Mouse Supports UKFR

    That would explain a lot, thanks for the info