True Altitude?

[KG26_Alpha]

I've already stated the charts are not totally inaccurate,
but using Bombsite data even with a wizz wheel or Pilotwizz the bombs still drop longer/shorter than they should,
even when you taken have in to account ground elevation of the target,
I still have to use a "feeling" of where the bombs "might" hit instead of accurate an bombing solution
with the correct input data.

Tested ac:
Pe2
IL4
The payloads on these aircraft all drop long as pointed out in an earlier thread >> http://forum.1cpublishing.eu/showthread.php?t=40740

He111
Payload drops short of aiming point, where as they used to run in from the start point of the bombsite.
The SC50 track is interesting as it hits before the aiming point and then long as you would expect from 32xsc50's


But as I have already said also, these bombsite shouldn't be too accurate, but some explanation the payload drops inconsistency would help matters,
be it the air density changes or other factor.






.

[Soldier_Fortune]

Hi...!

Finally I could upload my last tests: one with a Pe-8 and other with a HE-111.

Today I may not see your tests because I haven't IL2 installed in this computer (perhaps tonight or tomorrow).
BTW: what maps have you used? It is importan to know it.

[KG26_Alpha]

Originally Posted by Soldier_Fortune

BTW: what maps have you used? It is important to know it

Crimea

[Soldier_Fortune]

The OAT at MSL is 25 ºC for Crimea. Thus, the old chart remains useful in that map.
But, when it is used with winter maps, it just gets mislead the reader.

I've made a chart for OAT = -20 ºC, and I'm attaching it to this post.

Please: When you can, play a bomb mission using the Gulf of Finland Winter map, and observe how much 'feeling' you need to apply whether using the old chart and the latter.

[KG26_Alpha]

Have you checked the bombsites accuracy with different payloads ?

Even on the Crimea map its wrong especially the Russian bombsite.

Its very inconsistent compared to how it was before, with the bomb blast radius reduction and other bomb related adjustments, its become very laborious and painful to make a bomb run not knowing where the bombs are going to hit and see such little damage made by them if you just a few feet away from a target.

[Soldier_Fortune]

Originally Posted by KG26_Alpha

Have you checked the bombsites accuracy with different payloads ?

Even on the Crimea map its wrong especially the Russian bombsite.

Its very inconsistent compared to how it was before, with the bomb blast radius reduction and other bomb related adjustments, its become very laborious and painful to make a bomb run not knowing where the bombs are going to hit and see such little damage made by them if you just a few feet away from a target.

I'm doing my tests with different payloads and, as far as I can see, there is not relevant differences among them: russian bombs tend to fall long while the german ones tend to fall short.

Even on the Crimea map its wrong especially the Russian bombsite.

Last evening I was testing "how much feeling is needed" for an accurate targeting using the russian bombsight, with both Gulf of Finland maps.
And I was realized that the TRUE ALTITUDE (it means: Indicated Altitude corrected by OAT) has something to do as I suspected.
I've got very good shots in both maps in this way... but more tests are needed using different payloads and different russian bombers.
Other similar tests should be made for manual targeting with the Norden/Lofte bombsight.

Rgardless of the blast radius (it only could be fixed or modified by TD) I'm pretty sure that we're going in the right direction.
The level bombing is more laborious than before... but now is a bit closer to the real life. Perhaps we'll find a method to systematize the process and to make it more accesible to any player.

[KG26_Alpha]

Originally Posted by Soldier_Fortune

The OAT at MSL is 25 ºC for Crimea. Thus, the old chart remains useful in that map.
But, when it is used with winter maps, it just gets mislead the reader.

I've made a chart for OAT = -20 ºC, and I'm attaching it to this post.

Please: When you can, play a bomb mission using the Gulf of Finland Winter map, and observe how much 'feeling' you need to apply whether using the old chart and the latter.

Will test this soon.







.

[Soldier_Fortune]

Hello!

Yesterday I was carrying out more bombing tests, and I realized that actually with the Lofte BS the manual targeting is much more accurate than the auto targeting. Well... really we could say: actually the manual targeting is the only accurate method for level bombing.
This has a problem: the player should do all the calculations related with 'parabolic motion' and the BS elevation angle by himself.

I also tested the manual targeting with the OKPB-1 bombsight. And, surprisingly, I realized that the in-game calculation indicates an elevation angle greater than the calculated manually. The difference is about 3º, regarding of the altitude and the OAT, and that is sufficient to produce the observed longer drops with the russian bombers.

Thus: The intended aiming method of both types of bombsights (Lofte/Norden and OKPB-1) don't work as it should do.

Other important matters about manual targeting with both bombsights:

- The TAS must be calculated taking in account both the Indicated Altitude and the OAT at such altitude (remember: the OAT depends of the chosen map).

-The altitude to use for the BS' elevation angle calculation must be the True Altitude: it is found from the Indicated Altitude affected by OAT and then subtracting the Target Altitude.

All indicates that now the atmosphere model is more accurate and more consistent with the laws of Physics, and the aircrafts as well as bombs exhibit a more complex but predictable behavior according with a given combination of external conditions: altitude, OAT, wind, etc. Almost like IRL...

But perhaps something was missed about the bombsights along the succesive improvements, since the patch 4.10 until today.

I'll do more tests with different maps and with American and Japanese bombers. In the best case, such tests should confirm what was observed with the He-111 and the Pe-8.

[Soldier_Fortune]

Hi...!

Lately I was performing more tests.

First of all, I was mistaken about the altitude setting for manual targeting of the BS: it must be the Indicated Altitude.
I had seen the error when I tried to repeat my tests wih winter maps (for maps with OAT between 20 and 25 ºC @ MSL, at an altitude of 5000 m the difference between True Altitude and Indicated Altitude is practically negrligible).

I've made other tests, this time including the effect of the wind to see how it affects the calculations for manual targeting.

The observed effects (always with manual targeting) were:

1) Always, and regarddless of the wind direction and speed, it's needed to calculate the Ground Speed (GS) and the Wind Angle Compensation (WAC).
This is best done with an E6-B Flight Computer.

2) In order to mantain the True Course to the target, the aircraft must be pointed to a True Heading = True Course + WAC (or -WAC, regarding if the WAC is to the right either to the left).

3) For nose wind GS is less than TAS. Conversely, for tail wind GS is greater than TAS.

4) GS, and not TAS, is the speed input for the BS. TAS may be used only when Wind Speed = 0 (this is the only case in which GS = TAS, as it was until the patch 4.09, when the wind wasn't included in the FMB).

5) Indicated Altitude is the other input for the BS.

6) The BS must be aimed using its Side Slip command, with an angle = WAC, but with the opposite sign; i.e., if WAC = -7º then side slip angle = +7º.

7) The bomber must mantain both the True Course and True Heading, at least until the bombs are released.

If all the above is satisfied, the cross wind will make the bombs hit on the target.

[Soldier_Fortune]

Good morning.

I've made and attached below a set of 4 printable Manual Targeting Charts. The Readme into the .zip file explains how to use them.

The cons of these charts: they must be used together with an E6-B Flight Computer.
The pros: they are printable and can be used in-flight.

It is very easy to learn how to use an E6-B, and really it is a cool and useful tool... specially if you like to fly without waipoints.
IMHO, Il2 linked to a combo of printed maps and charts, an E6-B, a plotter and a pencil, is the more realistic and historical approximation to the work that made the airmen in the 40's... for pre-flight planning and navigation, at least.
The price of an E6-B ranges from about 15 up to 50 U$D, regarding of its material (metal, plastic fiber or paperboard) and its trademark, and it can be purchased in aviation stores and online.

But perhaps many players would prefere a "digital age" solution instead of the proposed "old analog age" method.
Yesterday I found this thread in the Warbirds of Prey forum, containing a very complete calculator for manual targeting. It does all what we were talking about in this treath in a very fast way.
I used it to compare the BS Elevation Angles obtained with my charts against those obtained with this calculator: within the desirable accuracy limits, the differences are negligible.

The pros of this calculator: very easy to use and the user doesn't need to learn nothing.
The cons: it is an online calculator and therefore it can not be used inflight; the player must pause and minimize the game and then open the calculator.

Well... Now the level bombing fans have two different methods to perform manual targetings. Both are very accurate and replace the old and obsolete charts and tables. So the choice depends on the tastes of each player.