Bombing Trajectory Planner (WIP)

[Boagord]

For some time now, we have been trying to compensate for the lack of a weapon delivery planner tool in DCS.

There are already some excellent pop-up attack planners available, but none that are well suited for loft or high-altitude bomb drops. Sometimes, when preparing a mission, we need to know how far from the target we can drop our bombs or how to optimize our trajectory. What should we expect?

The goal of this tool is not to achieve pinpoint accuracy on a target but rather to understand what is possible and what isn’t, and to visualize what will happen in the game before the mission begins.

The method implemented to develop this tool is broken down into several steps:

• Data Collection: We recorded the readings provided by the F-4’s bombing computer by varying different parameters in order to estimate the drag coefficient (Cx).
• Ballistic Calculation: Using this data, we performed a ballistic calculation to predict the bomb’s impact point based on certain parameters.
• Adjustment According to Bomb Type: An average correction—based on a coefficient that replaces the bomb’s effective surface area—was applied to account for differences between types of munitions.
• Validation and Correction: The results obtained were adjusted to match the current data provided by the F-4’s bombing computer.

Even though this approach has its limitations and I do not claim to have the perfect method, the overall result is quite satisfying, especially for Lodrag bombs. Your feedback and suggestions are very welcome, as I remain an amateur—sometimes a bit clumsy—eager to fill a gap in DCS and continuously improve this tool, so any help or ideas are welcome.

 

https://docs.google.com/spreadsheets/d/1C-UjHGR9P5EDAeDXvKEoe7PAes8WeBPKWpGU4u3lCO0/copy?usp=sharing

[Karon]

Great work, thanks!

[SOLIDKREATE]

This is good stuff. Are you going to add in the correction for wind speed and direction? 

You can add this too if you like:  https://docs.google.com/spreadsheets/d/1O1V4MVBnRgsAsmFPIxrTzoTr_LrorHkFx_clqC4s-QY/edit?usp=sharing

Edited March 18 by SOLIDKREATE

[Boagord]

3 hours ago, SOLIDKREATE said:

This is good stuff. Are you going to add in the correction for wind speed and direction? 

You can add this too if you like:  https://docs.google.com/spreadsheets/d/1O1V4MVBnRgsAsmFPIxrTzoTr_LrorHkFx_clqC4s-QY/edit?usp=sharing

Thanks for the feedback. It can be done, but before going further, I'd like to know if the tool is accurate and useful in real-case scenarios.

I have little data on the accuracy I can achieve with pitch angles different from zero.

From experience, it's decent, but I don't really know how it's handled in the game and in the F-4's bombing computer.

[graveyard4DCS]

Excellent tool, thank you. 

I confirm that your data are accurate enough for GBU-12 delivery profiles when using the Mk-82 data. 

The impact angle is fairly high compared to the GBU due to the final lasing phase, that seem to let the bomb have a constant dive angle once laser spot is acquired (so theoretically we could also estimate it from bombs position at lasing start, eg 8 seconds before impact for auto lase).

Let me know if you'd like me to share the limited data I have. 

[AndyJWest]

Interesting stuff.

I can't link them (forum rules), but there are real-world 'official documents' with tables giving ballistic data for Mk 82s etc which seem from a quick check to give similar but not identical results.

As for GBUs, from comparing data the same document it confirms that they are a little more draggy, as one would expect. As graveyard4DCS notes, a GBU isn't going to be following a ballistic trajectory though (or not intentionally ), so the difference need not be significant.

 

[Boagord]

Thank you for these responses.

I added a calculation of the bomb-to-target angle at the moment the target enters the bomb’s FOV (adjustable FOV) and another calculation of the bomb-to-target angle T-X seconds before impact.

The results seem consistent to me, but since I did it quickly, I hope there are no mistakes.

@AndyJWest : I think I have the document you're referring to, but DCS and reality don't exactly match when it comes to ballistics.

 

https://docs.google.com/spreadsheets/d/1r1b88Y58dCQsrn_2-Vgo-SsyT1A3pLAydKNTaPoctdQ/copy?usp=sharing

[Boagord]

On 3/18/2025 at 8:40 AM, SOLIDKREATE said:

This is good stuff. Are you going to add in the correction for wind speed and direction? 

You can add this too if you like:  https://docs.google.com/spreadsheets/d/1O1V4MVBnRgsAsmFPIxrTzoTr_LrorHkFx_clqC4s-QY/edit?usp=sharing

Thank you!

I'm not convinced that taking wind into account significantly improves my tool's accuracy. The tool is only precise to about 0.1 Nm and is mainly used for mission preparation and providing a rough estimate of the expected outcome.

For a highly accurate drop, you need to rely on the equipment provided by the aircraft. In my experience, manual drops are extremely challenging because it's difficult to get all three parameters right—speed, for instance, greatly affects the impact distance. Ultimately, the pilot’s precision ends up being lower than that of the tool.

Similarly, it's much like amateur fuel consumption calculators: they give you a general idea of what to expect, but they aren’t very accurate. In most cases, including wind data only complicates the system without offering much added value.

For example, when accounting for wind, you’d have to specify the wind conditions at various altitudes.

However, if you come up with a method to perform this calculation, I suggest explaining it to an AI and integrating it into the Google Sheets copy.

Edited April 2 by Boagord