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Looky what I'll be playing with today! [Updated]

 Wheee!  Embracing my inner Gunnery God!



Update: Since Grimmy got all snarky in the comments - click here.

34 Comments

 C'mon, Redlegs among us!  How many of you have got a plotting set at home?  Eh?
 
Haven't seen that in years. Are you going to fly a baloon and work up a met message?
 
 Nope.  I'll just register and generate a TFT setting that way.

 
Where's the boxes full of firing tables?
 
You're gonna need a set of grid lights.  Those ones on your cannon ought to do.
 
  And I shoulda said I'd generate a GFT setting that way. Not a TFT setting.

As for Grimmy, being snarky as is his wont - ">http://www.thedonovan.com/gunstuff/tft_and_plotting_board.jpg">here, bubba.
 
 Grimmy did say *boxes* of firing tables. I see only one set in that other pic. (runs and hides when I see Armorer reaching for his box of rocks)
 
Does it come with crayons?
 
 J(NTA) - the red and blue pencils are a form of crayon, smartass.
 
Be sure to sharpen your pencils correctly!!
 
F-sword... note the sharpeners! Both types are present. Congrats, sir, you scored serious geek points!
 
John,
Since you trashed the link, I tried to fix it manually, and got "This Is a No Debbie S Zone. Go back where you came from.", with my IP. WTF,O?
Why you treat an old cannon-cocker that way?
 
Stormin' Norman is no more...
Thank you, Bear for your service and example.
Cleared to Fiddler's Green, Sir.

RIP.

 
So, assuming you have five different charges for the notional piece, how long would it take you to manually calculate a 5-round simultaneous Time-on-Target misssion from one tube?  I am assuming the pointer (to use a naval term) can crank the elevation handwheel at infinite speed, so that's not a consideration.
 
 Chris -it works for me in three different browsers on a desktop, laptop, and a tablet. I'm guessing the problem is transient.
 
John,
Here is what I see on Firefox, and you can see the exterranoeus > and quotes:
">http://www.thedonovan.com/gunstuff/tft_and_plotting_board.jpg">here, bubba.



 
 Here's a thought, Chris... click the link in the update to the post, vice the comment...
 
Got it, sir! Thanks, from a 13A.
Though, as a mere gunny, I never got to play with all that "up-market" stuff. Just lay the gun and pull the lanyard(and try not to shoot the OP off the top of the hill).
Although, one time at the Yakima Firing Center, we had some self-importent SOB commandeer a chopper and fly the other side of the range of hills we were shooting over.
The entire battery fired(105s), just as the helicopter popped-up over the hill. We watched, in awe, as those tiny black dots flew towards the helicopter. They missed! The chopper immediately dropped its skids into the pucker-brush, and flew down towards the battery. The folks that got out were shaking pretty hard. They had seen all those 105 rounds fly past them.
It was cool!
That was almost as cool as, after going through the class(at Sill) on "Variable Time / Proximity fuzes" where they emphasized "Do Not Shoot These In Heavy Rain", we did. The Capt and his driver were passing from right, to left, 100 yds in front of the gun-line. We ripped the crap out of his jeep, but they were uninjured.
Of course, they condemned the lot of fuzes as defective. Though they performed exactly as we were taught they would. It was pretty cool when they detonated 100 yards, or so, in front of the guns! Except for the Direct-Fire exercises, we had never seen such a thing!
 
Yes, Chris, stories are cool, but I was trying to  discuss how to do simultaneous time-on-target from one tube.

  Now, assume a mortar, with maybe six or so increment charges on each shell. We are shooting at people who are at about halfway of max range.  To simplify it, let us say that we want two shells to arrive on those guys at the same time. We are obviously going to fire those shells at different times, but want them to arrive on those peoples' heads at the same time. With different charges and different elevations, shells can arrive at the same place with different times of flight.

  If you fire yer piece twice, at the correct times, different times, because of different elevations and different charges and different times of flight, I betcha you can have both shells arrive at the same place at the same time.

How did I do, Major?
 
You're gonna need a set of grid lights.  Those ones on your cannon ought to do.
 
 Yeah, Centurion - we ignored that one when you put it up yesterday, too... ;^)

JTG - the trick you are describing was a staple at firepower demos.  It takes about three minutes to do the data.  How long it would take the gun to cut the charges and set the fuzes would depend on how much ready ammo they had.

You also have a range limitation, as the target can't be too far out nor too close, since achieving the effect requires both high-angle and low angle fire, and the required times of flight have to allow for the mechanical realities of serving the piece.

It is a *standard* feature on the Paladin, where on-board fire control and autoloader mechanize the process.  

Another firepower demo gimmick was "marking the trajectory" where you'd fire the same data but vary the time setting on the fuze so the rounds would burst at differnt points along the trajectory, one right after another.  That one was pretty much the exclusive trick of the light guns, firing their semi-fixed ammo, with everything pre-computed and pre-cut..  They're the only ones who could serve the gun fast enough for the visual effect to work.

 
Thanks for the update Boss.  Now with cat hair for reference!
 
JoA:

No snark was intended. I served for a bit in the S2 of a heavy arty bn. Had 8" and 175mm self propelled. (5/10 2MarDiv).

On my first "field trip" with that bn, I was seriously impressed with the number of "sea boxes" loaded with book after book after book after...book of fireing tables.

That's when I learned that time of flight of some arty bullets is so long that even the rotation of the earth has to be taken into account.
 
 Especially the closer you are to the equator.  Or, if you are shooting across the poles, that does interesting things to the trajectory, too.
 
Out of chart paper, but have everything else.  And can still compute a firing solution.  My TFT still has the Hasty TGPCs stapled into the front cover. 


 
URR - if you have an actual DA Form 4176, Target Grid, I'm in the market. I'm looking at having to use a graphics program to create one. Though I'm still trying to see if anyone at Fort Sill will let one go...
 
Lemme dig around the war chest and see how many I might have.  Used to have drawers full of 'em.   If'n I got extras, will come up on this push and you can shoot me an e-mail with your mailing address.
 
Well, yes, Major, if you look at my first comment, I assumed the guy twirling the elevation wheel on the piece could do so at, I dunno, 2000 RPM. There was also an implied assumption that the crew could load the piece instantaneously. I also mentioned that this only works in the middle of the range of the piece.

I was in Freshman Physics mode, there, with the inextensible cords, frictionless pulleys, frictionless planes for sliding upon, ballistics in a vacuum, assume a flat Earth, usw.
 
P.s. I got an 800 on the Physics Achievement Test when I took the SAT back in '67. I did so without doing even one calculation. I am right good at "folk physics."

Give me a mortar, and twenty minutes for familiarization, and I can kill you. I don't need no steenking sights.
 
P.p.s. That British 2" mortar is my favorite of them all: No baseplate, no bipod, no sights, and it was so short that dropping a shell into it was insufficient to fire it; you had to let the firing pin loose yerself after loading it.

No calculations, just "That looks about right."
 
Oh, my head hurts.  Reading all this reminds me of why I liked the direct fire of the M-60's 105.  Though the HEP was treading dangerously close to all this stuff.
 
 JTG - you aren't the only person in the conversation now, are you?
 
Why, no, and thanks! Keep it up, guys!

Yup, Rod, the more a gun resembles a ray gun and shoots _exactly_ where you point it, with zero time of flight, the easier it is to hit with it. 

Always assuming you can see the target, and it's not behind something really thick, or under something. Then you have to get arty, or hire aviators, or something.
 
Funny you mention the M-60, Rod. The weird old tanker up the street, when we were discussing the best round for use against politicians in the open, opted for Beehive, against my argument for canister.

  But he too is an old M-60 guy, and liked how that one worked. Steve (he) said it was something like the ultimate shrapnel, and would stay in one piece until it got close, and then loose the flechettes, assuming you got the fuzing right.  Steve admits Beehive prolly won't work too well out of a smoothbore.