How high is safe??

Discussion in 'Aviation' started by ComeSunt, Jul 1, 2006.

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  1. Debate in bar,

    How high would you have to fly to ensure that you could not be hit by your own 105 light gun or 81mm round?

    Answers on a post card...

    My pure guess would be 12,000 for a 81 and approx 20,000 for a 105?

  2. i used to be in mortar platoon, many moons ago. we were told that the rounds could go up to ten thousand feet.
  3. I have no idea, but surely it must depend on the angle of the barrel?
  4. It would be safer to fly under them. (Unless its 3 Para mortars......)
  5. Are you flying or firing?
  6. As I've mentioned else where, if the barrel was set vertical , roughly 29028 feet would be achieved. However they're are limiting factors such as wind speed, air temp and lots of other technical stuff, the main problem being the four foot trench that needs to be dug out so that the breech won't impact the ground during recoil. However the gun cannot be eleveated to 1600mills ( 90 degrees), The maximum quadrant elevation (angle between the barrel and the ground)that is achieveable , when firing in high angle, being 1244 mills (070 degrees). Therefore your guess of 20,000 does seem possible. The minimum Q.E, for shooting from cliffs, is -0100 mills ( -005 degrees).

    I've been spammed to tidy up the pamphlet store on monday, will have a look at the firing tables and get back to you.

    Am reading a book right now called Chickenhawk ( memoirs of a vietnam huey pilot), he recounts flying under arty shells and his copter rocking as the projectile passed by, most probably due to the displaced air e.t.c. Its a really good read.
  8. gearupflapup,

    Is that the lesson over, or is there just a little more to it?


    What about things flying slowly?
    The maximum wake vortices are produced when the maximum amount if lift is being produced.
    That would be during the take off and landing phases with all those flaps, slats, spoilers and airbrakes being deployed wouldn't it?

    Wake vortex shed by DLR's research aircraft ATTAS at airport Braunschweig

    If you are flying forward, your turbulent air will be behind you, so I reckon that unless you are performing levels turns and fly through your own wake, you wouldn't be making 'your flight a little bumpier'.

    Back to the original question'

    Do any aircraft actually carry this type of ammunition?
    Bit like the Concorde shooting itself down argument methinks! :lol:
  9. Sympathetic_Reaction

    Sympathetic_Reaction LE Book Reviewer

    I realise you are joking, but 105 are cleared on C130J/K and C17 I think. Pretty sure 81mm are cleared as well. I have this mad idea that one of the US C130 Spec ops aircraft has a 105mm gun mounted in it.....but i may be dreaming.
  10. AC130 Spectre.



    AC130H: Two M61 20mm Vulcan cannons, one L60 40mm Bofors cannon, one M102 105mm Howitzer cannon.

    AC130U: One GAU-12 25mm Gatling gun, one L60 40mm Bofors cannon, one M102 105mm Howitzer cannon.

    A world of hurt to say the least.
  11. M'learned friend Flash is correct. For any really sad spotters out there (and other FACs, clearly), the major difference in terms of weaponry between Spectre and Spooky is that Spectre has two M61 20mm Vulcan cannons as opposed to a single 25mm GAU-12 Gatling gun in the Spooky.

    Both have trainable side-firing 105mm howitzers and single 40mm Bofors cannons.

    It's a great piece of kit - what a pity we can't amend our doctrine to buy a couple for the AAC! :)

    Edited to add: It couldn't go to the Crabs as they'd never show up.
  12. According to Pam 21 the approximate maximum height for 81 using the Mk 4 charge system is 11,000 ft. No idea for the L118, better ask a gunner.