Author Topic: 190A5 Sticks ITT  (Read 1111 times)

Offline Saurdaukar

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190A5 Sticks ITT
« on: February 25, 2009, 12:42:26 PM »
A.)  Assumption:  No MGFF loaded. 

B.)  Situation:  High-G, high AoA, profile snapshot.

C.)  Settings:  7.9mm & 20mm set to identical convergence.

D.)  Result:  7.9mm's hit nose of EAC.  20mm's hit tail of EAC.

E.)  Catalyst:  Likely a differential between muzzle velocity and missile weight.

F.)  Goal:  Identical impact site.

G.)  Requirement:  Convergence differential.

AS (A+B+C) = D

AND IF E = True

AND IF F = Possible

THEN solve for G.

Thanks.  :)

Offline Rebel

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Re: 190A5 Sticks ITT
« Reply #1 on: February 25, 2009, 02:13:39 PM »
You forgot range to target ;) 

basically, just take the muzzle velocities for both weapons, compute the time it takes to reach distance X (your desired conv point).   

20mms will most likely be slower.

Now compute the distance carried by the cowling guns using the 20mm's time. 

Enter this new number for your cowling gun. 

It's very rough, but that should work okay- you could fine tune it from there.

"You rebel scum"

Offline Saurdaukar

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Re: 190A5 Sticks ITT
« Reply #2 on: February 25, 2009, 03:08:52 PM »
You forgot range to target ;) 

basically, just take the muzzle velocities for both weapons, compute the time it takes to reach distance X (your desired conv point).   

20mms will most likely be slower.

Now compute the distance carried by the cowling guns using the 20mm's time. 

Enter this new number for your cowling gun. 

It's very rough, but that should work okay- you could fine tune it from there.



Exactly.  I was hoping someone already did that.  :)

Offline Anaxogoras

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Re: 190A5 Sticks ITT
« Reply #3 on: February 25, 2009, 03:11:52 PM »
Convergence settings won't do anything to help that because they don't change muzzle velocity.
gavagai
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Offline Saurdaukar

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Re: 190A5 Sticks ITT
« Reply #4 on: February 25, 2009, 03:23:01 PM »
Convergence settings won't do anything to help that because they don't change muzzle velocity.

A change to muzzle velocity is not required.

I'm looking to craft an identical impact site - not an identical impact moment.

Degrees of elevation can achieve that.  I cant find the sweet spot, yet.

Offline Anaxogoras

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Re: 190A5 Sticks ITT
« Reply #5 on: February 25, 2009, 03:30:37 PM »
A change to muzzle velocity is not required.

I'm looking to craft an identical impact site - not an identical impact moment.

Degrees of elevation can achieve that.  I cant find the sweet spot, yet.

Oh, disregard then.
gavagai
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Offline Xasthur

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Re: 190A5 Sticks ITT
« Reply #6 on: February 25, 2009, 07:05:17 PM »
Just pull your MGs in by 50 yard increments until you find your sweet spot.

I'd start with the MGs and cannon at the same distance.

All of this will be affected by the distance to impact, G-load and size of the target, so I don't think there is going to be a golden 'master solution' to this problem.

Simple trial and error at your average shooting distance will probably yield the best results.
« Last Edit: February 25, 2009, 07:07:57 PM by Xasthur »
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Offline morfiend

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Re: 190A5 Sticks ITT
« Reply #7 on: February 25, 2009, 07:14:03 PM »
I believe this will only work for a dead six shot, any off angle shot wont have the same hit spot because of MV.
 If the EAC is crossing ,say from left to right,the higher MV rounds will always have a shorter lead requirement.

On the other hand,this imfo I'm sure your aware of....... :o

Offline Ghosth

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Re: 190A5 Sticks ITT
« Reply #8 on: February 26, 2009, 06:47:00 AM »
Pull the MG's in 50 in convergence. It will work best of course when stick is unloaded. However that does not necessarily mean a dead 6 shot. Could be a top down shot, bottom up, or any crossing deflection shot.

The bigger the gun, and the slower the more distance differential you'll need. Same if your trying to extend the range out.
Takes a lot more differential at 500 yards than it does at 250.

75 yards for 37 and 30mm, 50 for most 20 mm.

.target xxx for visual conformation of where your hitting.

Offline Saurdaukar

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Re: 190A5 Sticks ITT
« Reply #9 on: February 26, 2009, 12:29:45 PM »
.target xxx for visual conformation of where your hitting.

All this time and I didnt even know that was a command.

Thanks guys.  <S>

Offline HPriller

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Re: 190A5 Sticks ITT
« Reply #10 on: February 27, 2009, 03:10:33 PM »
Realistically it doesn't matter.  When I fly this plane, I typically go without the MGFFs.  The point is the machine guns are almost useless.  I typically use them out to a long convergence point for spray and pray at runners, to induce them into turning.  The damage that leads to a kill invariably will come from the cannons.  Whether or not they are converging with the MG fire isn't really relevant.  Set your cannons to converge at your best kill range, set the MGs out farther for the runners is my suggestion

Offline Widewing

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Re: 190A5 Sticks ITT
« Reply #11 on: February 28, 2009, 09:08:52 AM »
Many factors effect how convergence works. When you set convergence in the hanger, the aircraft is level with 1 g working on it.

When banked over at 90 degrees, the convergence elevation relative to gravity will be zero as the guns are now shooting with elevation settings parallel to the horizon (ground). This tends to allow the guns to better lead the target, but the rounds will track lower than if your fighter was wings level. This doesn't even consider g loading on the aircraft.

This is a very complex equation with constantly changing variables. Thus, it is unlikely that any accurate solution will be defined. Your best results will be when your aircraft is wings level. The further you deviate from wings level, the greater the error will be.


My regards,

Widewing
My regards,

Widewing

YGBSM. Retired Member of Aces High Trainer Corps, Past President of the DFC, retired from flying as Tredlite.