Hello all,
Snow back here with some more funky trees magic. This time around, I’ve created what I call a fire assistance system- note that it differs from a fire-control system- a system that allows operators to very easily range in cannon shots in long ranges.
In short, the Fire Assistance System is an extremely advanced system that automatically calculates the required angle of elevation for a cannon shell to reach an required distance.
The first of its kind in the history of SimplePlanes, you now need not zoom way out to try and make out where your shots will land- if you have a range to your target, this system will enable you to fire at it far more accurately and quickly than ever before.

In order to operate the system, you MUST read the first two sections of instructions.

As a fair warning, the system is not ready to use right out of the package. It contains basic components that you, as the operator, must adjust in order for correct functioning. This requires you to do some work (very little, but still some). I hope you keep this in mind before you use this system.

Let’s get straight to how to operate the system.

Controls

The system is composed of largely two components. One is a fire director, and the other is an automatic gunnery system. After you take download the build, you will see two things: one, a cannon mounted on a standard platform, and two, a round structure that contains various instruments. They are as shown below.

To use them on your other builds, take each of them off the rack. The attachment point is the baseplate for both items. When using them while in play, use the custom cameras to view the fire director interface. It should look like the following:

The automatic ranging system automatically calculates the required angle for a cannon shell to reach an inputted distance. In order to use it, use the input Trim in order to change the range you want. Each mil on the ranging system is calibrated to 500m in the included package, and is capable of receiving a range of up to a range of 5000m, or 5km. By manipulating Trim, you will see the ranging mils change. Simply adjust Trim accordingly such that the indicated range in the ranging system is the range you want your cannon to fire at. For example, if I want my cannon to fire at an area 1km (1000m away), I make it such that the display indicates 1000m. See below:

With this setting, this means that if I fire my cannon, the cannon shell will travel exactly 1000m from the cannon and hit there. Also notice that the hand on the shell splash timer has changed. The shell splash timer is made with increments of 1 second each, so in the displayed example it is nearly 3 seconds. This means that the shell will reach the target area, which is 1000m away, in 3 seconds. The timer will update accordingly to whatever range you select. This system incredibly simplifies ranging and firing at targets, especially for artillery purposes. With a known range to the target, you now can immediately fire with deadly accuracy and precision.

This isn’t all, however.

You can also adjust the settings on the ranging system to have automated gun laying for ranges as far as your shells can reach. The ranging mils will just indicate the range in increments of 1/10th the maximum range you set it to. However, the shell splash timer is confined to a maximum of 30 seconds, so I do not recommend using the system for ranges above 10 km. I will discuss how to set up the system. This next section is critical. Do not skip it.

Initial Set-up

Notice how I did not discuss the second component- the gunnery system in the previous section. This is because you do not directly control the gunnery system. Instead, it is done through the fire director, which is the interface you can actually control. However, in order for the gunnery system to work, you must first set it up. Please read carefully.

The gunnery system is regulated by a standard turret platform. This is a 90º rotator for the horizontal platform and a 90º hinge rotator for the vertical elevation. Assuming this is also true for your system, there are only two things you need to set up to use the system. First, use Overload to select and view the attributes for the hinge rotator on the gunnery system. Next, move to the inputController section. You should see the following:

The input attribute should display (asin((5000 * Trim * 9.81)/(pow(v, 2)))/2)/90. Do you see the letter v in that statement? This is the muzzle velocity of your cannon. Go ahead and replace that letter v with the muzzle velocity of the cannon you will fire (it should be in m/s), and click on the check button to finish. You are now halfway done.

Now zoom into the semi-sphere section of the fire director (clip into it). You should see a lot of things there, but now just look at the shell splash timer. There is a rotator (highlighted) in the dead center of the timer, as shown below:

Use Overload to bring up the inputController class for the timer’s rotator as well. You should see this:

The input attribute should display (((v * sin(asin((5000 * Trim * 9.81)/(pow(v, 2)))/2))/9.81) * 2) * (12/90). Do you see the letter v in that statement? This is the muzzle velocity of your cannon. Go ahead and replace that letter v with the muzzle velocity of the cannon you will fire (it should be in m/s), and click on the check button to finish.

You have now completed calibrating the fire assistance system to your cannon. Feel free to shell everyone else on the battlefield with unparalleled reaction times and accuracy. There is no “dialing in shots” now. You will hit the first shots with this system.

Extras

If you want to use the system with a maximum of 10 km instead, please use the following input statements for the system, accordingly:

Hinge rotator: (asin((10000 * Trim * 9.81)/(pow(v, 2)))/2)/90
Timer: (((v * sin(asin((10000 * Trim * 9.81)/(pow(v, 2)))/2))/9.81) * 2) * (12/90)

If you use the 10 km option, each mil will now indicate 1000m.

Comments

Note that this is dubbed a fire-assistance system. This is a radically simplified version of a fully fledged fire control system, as it lacks lead compensation. I am currently working on a fully fledged fire control system, but I expect it to take some time before it is ready for public consumption. This system, while much simpler, is easier to use and is still quite useful, so I decided to release this first as a proof of concept.

If you want to find out how I made the calculations for this thing, read the forum post here.

Hope you enjoyed. I’ll get back here next time with either a functioning surface-to-surface fire-control system, functioning anti-aircraft fire-control system, or both. This next project should be a fully fledged system able to compensate for target lead.

As always, have fun.

• SnoWFLakE0s

Much thanks to peeps in SPBC and especially spefyjerbf for the help with my description and testing!