[Soldier_Fortune]

Hi FrankB!

So some other variable comes to the play when calculating the bombing angle - maybe the air density/resistance...

As far as i could test and see, no ballistic affects are modeled for the bombs within IL-2, and their motions my be described through the Laws of Newton.
I've made a set of charts (attached to post #30) for "fixed angle bombing" based on those laws, and I'm achieving good hits with them.

Test environment:
- stock 4.12.2
- SB-2, 100% fuel, 6x100kg bombs
- altitude 2000m
- IAS 330km/h
- bullseye placed at 0m elevation on the shore to simplify the calculations
- no wind on the maps
- coming in from the water

For these data, using the OPB-1 chart and an E-6B, I got the following settings:

Moscow winter: OAT@GL = -17 ºC
OAT @ Flight Altitude = -30 ºC
TAS = 340 km/h
BS Drop Angle= 44º [This value is affected by the interpolation while the chart is being read, and the player's judgement about the angle setting for the bombsight: the OPB-1 can be set with a precision of 0.25º/keystroke (it means: you need 4 keystrokes to increase or decrease the BS angle by 1º)].

I'll test them tomorrow, flying a SB-2, and then I'll tell you my results.

Results:
- good hits on the Crimea map (at least one bomb landed within the pattern)
- bombs fell short on Moscow winter map by at least 3 patterns

OK: your tests with the Crimea map are consistent with your data above.
But... How did you got "0 m ground altitude and shores" in the Moscow map?
In the Moscow map the ground is mostly flat... but the average ground altitudes are about 400 @MSL. If you've considered too low altitudes in your calculations, it may explain why your bombs fell short.

Let me give you some tips about level bombing:
- As lower is the chosen altitude for level bombing, as worse is the accuracy.
A good altitude is above 4000 m. Think like a bombardier: if you must carry on a pin point bomb mission flying at low altitude, it is better to use a bomber designed for such class of missions; e.g.: a Pe-2 or an IL-2.
Level bombing doesn't allow evasive maneuvers while you are flying the last leg of your bomb run. Therefore, if you are flying too low following a foreseeable path, you will make happy the flak crews.

A difference of 100 m @ MSL within an altitude of 2000 m, means an altitude error of 5% and 2.5% for the distance. The same difference of 100m, but within an altitude of 6000 m, gives an error of 0.85% for the distance.

It is easy to check the altitude for airfields: you only need to place a plane on the ranway of the targeted A/F, while you're designing your mission with the FMB, and read the altimeter. But it's more difficult to know the GL altitudes for other targets.
This other reason to bomb them from higher altitudes, to improve the chances to hit them.

- Don't use the Speed Bar data as inputs to set the bombisght.
The Speed Bar readings are less accurate than the gauges readings, with the sole excepcion of the Heading.
Speed Bar gives IAS and ALT in steps of 10. It means that you could read 230 km/h in the Speed Bar, but 239 km/h in your IAS-meter. What is true? The latter. For altitude, a difference of 10 m is negligible. But a difference of IAS = 9 km/h, it's not.

I hope these tips will help you to improve your enjoyment.