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Old 09-14-2013, 04:57 PM
Soldier_Fortune Soldier_Fortune is offline
Approved Member
Join Date: Jan 2013
Location: Madrid, Spain
Posts: 68

Hi all.

I'm performing several tests since de patch 4.12 about flying navigation an level bombing, watching two important effects: the wind speed and the free air temperature.

Wind speed and its direction have effects on your true heading in order to flight following a preplaned true course to your target. But also the wind affects your Ground Speed.
If in your mission there is wind with a non "zero speed", you shouldn't use TAS to set your bombsight up, but the Ground Speed. This must be solved knowing your TAS and the wind speed at a given altitude, as well as your course and the wind direction.
To find the Ground Speed (GS) you can use the "Cosin's Theorem", or solving the vectorial sum between TAS and Wind Speed (WS)... or using the back side of an E6-B Flight Computer (as I do ). So, TAS may be used only when there is not wind (in such case, GS = TAS as it was before the patch 4.12).

The free air temperature affects both the TAS and the True Altitude (TA): when the air is colder it is denser, and your TAS will be slower than that measured in your TAS gauges, or that computed for any given warmer temperature. The same is for the altitude: in colder air your real altitude may be a bit lower than that indicated by your altimeter... or a bit higher if the free air is warm.
In air navigation it's admitted that the free air temperature decrease -6.5ºC each 1000 meters ASL. At sea level (for air navigation) the standard temperature is 15ºC; and from 11,000 m to 20,000 it's accepted the air temperature has a constant value of -56.5 ºC.

But, what if the air temperature on the ground level is not the standard value of 15 ºC?
The step of -6.5 ºC each 1000 m ASL doesn't change... but it means that you will find the limit of -56.5 ºC below of 11,000 meters (i.e., in a winter map), or above of 11,000 m (i.e., in a summer map).

So, the free air temperature at a given altitude affects the True Altitude and the TAS. And if there is wind, also it affects your GS. All together are combined and must be taken in account for the right setting of your bomb sight. Always I compute all these values with my E6-B and normally I find good results... and in any cases I've obtained the same bias with the same bombers using different bombs. Of course, I must perform more tests for to obtain a conclusion... but till now it seems that TD has implemented a very realistic atmospheric behavior.

About the bombs' FM, my tests let me guess that the FM is the same for all bombs, regardless of their sizes and their countries.

I hope this spots the new challenges of IL2-1946 propossed by TD.
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