High level bombing questions

[Woke Up Dead]

Two questions about high level bombing.

Does anyone have a IAS/TAS conversion chart for the cold maps in IL2, like Moscow? Bombsight Table 2 and all the charts I can find seem to be calibrated for average spring/fall temperatures, but the Moscow map is much colder, which affects TAS calculations, which in turn affects bombing accuracy.

For example, on the Crimea map, at 3950m and an IAS of 270km/h the TAS is 340km/h, according to the wonder-woman view. But on the Moscow winter map, IAS of 270km/h at 3950m is 312km/h.

If someone had a chart, or at least a basic guideline for calculating TAS on winter maps, that'd be great.


My second question pertains to the Soviet bombsight on the Pe-2, Pe-8, and IL-4 (now also found on the single-engined Japanese bombers). I find it to be very precise but not accurate; it consistently drops bombs with the same error, depending on bomb type and plane type.

BFS Thor made a great level bombing manual with a chart to correct the Bombsight Table 2 program, but it does not include the IL-4 or the Pe-8, and the Pe-2 information is now inaccurate or was never accurate to begin with. Doing my own tests on the Crimea map, I found the following corrections are needed, all at 3950m:

Pe-2, 250kg bomb: go by the sight
Pe-2, 500kg bomb: go by Bombsight Table 2
IL-4, 250kg bomb: go by Bombsight Table 2 + 0.4 degrees
IL-4, 500kg bomb: go by the sight
Pe-8, 500kg bomb: go by Bombsight Table 2 + 2.0 degrees
Pe-8, 1000kg bomb: go by Bombsight Table 2

Does someone have a more complete chart, and is it possible to fix these inaccurate bombsigts in future patches?

Thanks,

WokeUpDead

[DD_crash]

HSFX has an option to show TAS in the speedbar.

[T}{OR]

What you need is PAL-HUDConfigHSFX6 mod for HSFX (I am guessing that you are using mods?), available here in JSGME package for HSFX 6 in DBS mods section.

Visit our DBS forums (link in my sig) for more info (not sure if I can post mod links here).


Alternatively you can do what I always do, since the bomb angle varies so much depending on the bomb size, use BombsightTable2 for IAS-TAS conversion and then input the accurate data into the OP-1 bombsight through in-game interface rather than dropping on a preset angle.

[Woke Up Dead]

Thanks for the replies, I don't use mods though, and the servers I fly on may not allow that specific mod anyway.

"use BombsightTable2 for IAS-TAS conversion and then input the accurate data into the OP-1 bombsight through in-game interface rather than dropping on a preset angle"

Do you mean use BT2 to figure out the TAS, then ignore the angle BT2 gives and just line up the two needles on the sight? Unfortunately this does not always work, hence my problem from my first post. Different sizes of Soviet bombs do seem to fall differently, I think you found this yourself when you added different correction angles for the big bombs (BB) and medium bombs (MB) in your guide. But the OP-1 always gives the same angle given the same altitude and speed, regardless of the bomb size. And there also appears to be variation from plane to plane (Pe-2, IL-4, Pe-

[KG26_Alpha]

Originally Posted by Woke Up Dead

Two questions about high level bombing.

Does anyone have a IAS/TAS conversion chart for the cold maps in IL2, like Moscow? Bombsight Table 2 and all the charts I can find seem to be calibrated for average spring/fall temperatures, but the Moscow map is much colder, which affects TAS calculations, which in turn affects bombing accuracy.

For example, on the Crimea map, at 3950m and an IAS of 270km/h the TAS is 340km/h, according to the wonder-woman view. But on the Moscow winter map, IAS of 270km/h at 3950m is 312km/h.

If someone had a chart, or at least a basic guideline for calculating TAS on winter maps, that'd be great.


My second question pertains to the Soviet bombsight on the Pe-2, Pe-8, and IL-4 (now also found on the single-engined Japanese bombers). I find it to be very precise but not accurate; it consistently drops bombs with the same error, depending on bomb type and plane type.

BFS Thor made a great level bombing manual with a chart to correct the Bombsight Table 2 program, but it does not include the IL-4 or the Pe-8, and the Pe-2 information is now inaccurate or was never accurate to begin with. Doing my own tests on the Crimea map, I found the following corrections are needed, all at 3950m:

Pe-2, 250kg bomb: go by the sight
Pe-2, 500kg bomb: go by Bombsight Table 2
IL-4, 250kg bomb: go by Bombsight Table 2 + 0.4 degrees
IL-4, 500kg bomb: go by the sight
Pe-8, 500kg bomb: go by Bombsight Table 2 + 2.0 degrees
Pe-8, 1000kg bomb: go by Bombsight Table 2

Does someone have a more complete chart, and is it possible to fix these inaccurate bombsigts in future patches?

Thanks,

WokeUpDead

To accurately bomb in those aircraft you need the target ground level altitude to calculate the bomb sight angle.

Or you will be long/short depending on the target alt from mean sea level.

I have never found it necessary to use any bombsite assistance programs the stock tables work perfectly well if you know the target alt







.

[T}{OR]

Target elevation (the correct term ) is very important when level bombing. You need to input the relative altitude above ground or AOG, not altitude above sea level or AOS for your target. In IL2, due to its terrain, those targets usually will not be above 200m AOS and that is rare since the terrain is mostly flat on all maps with very few exceptions. The highest target I ever bombed was MonteCassino on Italy map (600m AOS).

Originally Posted by Woke Up Dead

... But the OP-1 always gives the same angle given the same altitude and speed, regardless of the bomb size. And there also appears to be variation from plane to plane (Pe-2, IL-4, Pe-

Could very well be so. Bear in mind that the angle value needed is a decimal number, i.e. in 1/3 that needs to be entered into the bomb sight. Depending on what the sight gives you. Three clicks are needed with OP-1 to switch to a higher angle. That may also be important.

[KG26_Alpha]

Originally Posted by T}{OR

Target elevation (the correct term ) is very important when level bombing. You need to input the relative altitude above ground or AOG, not altitude above sea level or AOS for your target. In IL2, due to its terrain, those targets usually will not be above 200m AOS and that is rare since the terrain is mostly flat on all maps with very few exceptions. The highest target I ever bombed was MonteCassino on Italy map (600m AOS).

Altitude deviations at airfields on a few of the common stock maps.

~@ Woke up Dead
Its important to know terrain elevation on parts of the maps you are intending to use altitude bombing.

Moscow
North 90m
South 140m

Crimea
South 200-240m

Smolensk
East 160m
North 90m
South 110m
West 40m

Stalingrad
North 200m
South 30m
East 50m
West 100m
Central 110m

[Woke Up Dead]

Thanks again guys, but I think you're assuming I'm more of a novice at this than I really am. I'm aware of the importance of target altitude; for my recent tests I either targeted objects at the coast line or along rivers, or took target altitude into consideration.

I'm also aware that it takes multiple clicks to increment move the Soviet bombsight by angle integers. Not three, but five; increments of 0.2 degrees: 0.0, 0.2, 0.4, 0.6, 0.8, 1.0, etc.

Given all this, I still can't get accurate results, even if I read my TAS from the wonder-woman view. I input the correct speed, correct altitude, match the two indicators on the bombsight, and still can't hit my target. The error is consistently the same if I use the same bombload and drop it from the same plane, but different if I take another bombload or another plane. For example, a FAB-500 dropped from a Pe-2 from 4000 may always fall a little bit long, but the same FAB-500 dropped from in IL-4 may always fall very long.

In other words, the Soviet bombsights in this version of the game are inaccurate, or to put it bluntly, screwed-up. I hope they get fixed for 4.13, in the meantime I may create a chart of corrections for the Pe-2, IL-4, Pe-8, and maybe the Japanese bombers as well.

[KG26_Alpha]

Originally Posted by Woke Up Dead

Thanks again guys, but I think you're assuming I'm more of a novice at this than I really am. I'm aware of the importance of target altitude; for my recent tests I either targeted objects at the coast line or along rivers, or took target altitude into consideration.

I'm also aware that it takes multiple clicks to increment move the Soviet bombsight by angle integers. Not three, but five; increments of 0.2 degrees: 0.0, 0.2, 0.4, 0.6, 0.8, 1.0, etc.

Given all this, I still can't get accurate results, even if I read my TAS from the wonder-woman view. I input the correct speed, correct altitude, match the two indicators on the bombsight, and still can't hit my target. The error is consistently the same if I use the same bombload and drop it from the same plane, but different if I take another bombload or another plane. For example, a FAB-500 dropped from a Pe-2 from 4000 may always fall a little bit long, but the same FAB-500 dropped from in IL-4 may always fall very long.

In other words, the Soviet bombsights in this version of the game are inaccurate, or to put it bluntly, screwed-up. I hope they get fixed for 4.13, in the meantime I may create a chart of corrections for the Pe-2, IL-4, Pe-8, and maybe the Japanese bombers as well.

I use the bombsite table as a guide to correct airspeed, but nothing beats experience in these situations, you need to experiment a bit with the sight and different speeds.






Using the Russian sight I drop the bombs at the start of the target they then hit the middle allowing for altitude deviation at ground level.

Just done a 3930m drop with

Pe2 (1942)
FAB 500's x 2
IAS 270kph
TAS 330kph
Target altitude (elevation) 30m

Perfect drop with a direct hit on the target using the @ 60kph speed difference as indicated on the bombsite table above.

Track attached.

[T}{OR]

Do you have wind on the maps you tested (I presume not)? In todays IL21946 it plays a key role when level bombing.