The Flak Gap

[Nikademus]

I'll stick with mine for the time being. it ain't perfect but it works and covers em all.

[Nikademus]

reminds me of that incident i referred too a page or two back. The UK IIRC underestimated the Ger Light/med effective range and suffered heavily at around the 10-13k range. They never bombed low (as general policy) again for the mainline units targeting cities etc.

[Big B]

ORIGINAL: Nikademus

People get confused because they keep interpreting "Flak gap" as meaning a complete gap of AA within a band of airspace. This is not what is meant. A "gap" in the coverage is created by the heavy flak guns ceasing fire (completely) at a minimum altitude leaving only light or med AA to fire in it's place.

So at 6000 feet (The game's long time sweet spot) you still experience flak, but none from any gun (HAA) that has a ceiling of 25,500 feet or higher.

The min alt requirements are as follows:

land AA with a max ceiling of between 33-36000 feet will not fire at 8000 feet or less

land AA with a max ceiling of between 29-32,000 feet will not fire between at 7000 feet or less

land AA with a max ceiling of between 25.5 - 28,000 feet will not fire at 6000 feet or less


This is not how it is done in BTR hence there is no exploitable flak gap and bombers that go in at WitP alts get slaugtered if the defences are strong enough.

Thinking out loud, given the above information, and the effective targeting difficulties of accurate targeting as jwilkerson pointed out,... two related thoughts have come up.

1) should those big guns really be allowed to effectively shoot that low?
and
2) if the answer above is "not really", then is the real problem that light AAA is just too ineffective from 6000-9000?

[Nikademus]

Eliminating the flak gap alone will admitedly, not do a whole hell of a lot. AA remains anemic save for a couple special cases....(Dive bombers for example)

[Big B]

ORIGINAL: Nikademus

Eliminating the flak gap alone will admitedly, not do a whole hell of a lot. AA remains anemic save for a couple special cases....(Dive bombers for example)

Hmmm, requires thought...

[Nikademus]

requires better AA but this has been the case since UV. Nothing new here.

[Apollo11]

Hi all,

ORIGINAL: Apollo11

Hi all,

ORIGINAL: jwilkerson

ORIGINAL: Apollo11



Just one sidenote - although Germans made great strides in accuracy when they stopped using "barrage FLAK fire" the Allied bombers looses droped around 4x (four times!) IIRC...

I will post the exact figure later today (I am at work now) but in book I have:

Fighting the Bombers : The Luftwaffe's Struggle Against the Allied Bomber Offensive (World War II German Debriefs)

There were two cases of "institutional" use of "barrier fire" by German Hvy AA units. The first was in 1940 and was due to combination of ammunition surplus (a problem not to be repeated [:D]) and lack of director equipment. During this period shoot downs were down dramatically and "barrier fire" success even more so. So for example in Dec 1940 directed fire accounted for 22 out of 23 aircraft shot down, while barrier fire accounted for 1. The second institutional use of "barrier fire" was in flak units equipped by "foreign" equipment as these batteries were not equipped with director equipment. And the use of "barrier fire" tactics in these units remained in effect for the duration of the war.

The Germans used the strict measure of "shoot downs" as their metric for flak success. They debated whether "disrupting the aim" of the bombers was perhaps not the real goal of flak. But this less objective metric was not adopted, so the Germans continued to seek solutions which increased the shoot down rate.

I will look exact passage in book I have (and I don't have any reasons to doubg sources in that book especially since they were mainly official after war debriefs):

Fighting the Bombers : The Luftwaffe's Struggle Against the Allied Bomber Offensive (World War II German Debriefs)

And will post it here.

IIRC the problem was due to ammo expenditures and by 1944 there was ammo shortage...

I was mistaken (but not completely)... [8D]

Now that I am at home I browsed through my book and couldn't find the paragraph that so vividly stuck in my memory (and which I mentioned above).

Then I remembered that in parallel with that aforementioned book I read the on-line available document:

"The Wizard War: WW2 & The Origins Of Radar"

by Greg Goebel

http://www.vectorsite.net/ttwiz.html


This is the paragraph:

Even when their radar was blinded, the anti-aircraft batteries generally kept up a heavy rate of fire, focused on the best guess for where the intruding formation was, and actually scored enough kills to make Allied countermeasures officers wonder if the countermeasures were actually working. Such "predicted barrages" also helped reassure the local population by at least giving the sound of putting up a strong defense. However, predicted barrages wasted enormous amounts of ammunition. During a raid through overcast by 720 USAAF bombers on Hamburg on 25 October 1944, the Germans fired over 24,400 rounds of heavy anti-aircraft ammunition, and shot down one bomber. Shortly after that, faced with using up ammunition faster than it could be manufactured, the practice was restricted to defense of high-priority installations. Bomber losses to flak then fell by 75%.

Leo "Apollo11"

[AmiralLaurent]

ORIGINAL: treespider

When you bring some data then I may shut up - until then I've quoted a source that says the "effective" ceiling of 13mm was 13,000 feet...

Part of the problem with this "effective" range is that to be "efficient" as an AA system, low caliber weapons should strike multiples round into an aircraft... or be very lucky... while a 37mm or higher may very well shot down any aircraft directly hit. Of course much shot downs by 75mm and more were not direct hits but shells exploding nearby enemy aircraft (the proximity fuse that was used by the USN since 1943 being for that a big progress).

You also have to take into account the targetting system available, and the way the weapon had to feed to continue to fire and moved to track the target.

All this should give a "combat effective" range far below the theorical one. As the "combat stats" of aircraft should be lower than the "designer" stat. Battle-worn aircraft with full ammo were certainly slower and could reach lower alt than during tests.

To come back to the AA gap, I have found that having some small base forces (with their light and medium AA guns) is far more efficient for AA defence at 6-7k (the usual alt for bombers in WITP) than having the same number of AA Bn (with heavy AA guns).

[greg_slith]

Actually, I read in "Invasion of Japan: Alternatives to the Bomb" (I think) that the Allies actually did know of an AA-Gap at just about the altitudes we WitPers have been using. They felt that the hight of 5-8,000 ft was where the light AA effectivness ended and before the med/heavy AA began. I was quite supprised that I hadn't been "gaming" the system after all.

[Big B]

ORIGINAL: ecwgcx

Actually, I read in "Invasion of Japan: Alternatives to the Bomb" (I think) that the Allies actually did know of an AA-Gap at just about the altitudes we WitPers have been using. They felt that the hight of 5-8,000 ft was where the light AA effectivness ended and before the med/heavy AA began. I was quite supprised that I hadn't been "gaming" the system after all.

I would imagine that if that is the case, the Allied flyers would have found out fairly quickly where the safest altitudes were - they were the ones getting shot at, and would be the first ones to figure out where the flak is least effective...

[treespider]

ORIGINAL: AmiralLaurent

ORIGINAL: treespider

When you bring some data then I may shut up - until then I've quoted a source that says the "effective" ceiling of 13mm was 13,000 feet...

Part of the problem with this "effective" range is that to be "efficient" as an AA system, low caliber weapons should strike multiples round into an aircraft... or be very lucky... while a 37mm or higher may very well shot down any aircraft directly hit. Of course much shot downs by 75mm and more were not direct hits but shells exploding nearby enemy aircraft (the proximity fuse that was used by the USN since 1943 being for that a big progress).

You also have to take into account the targetting system available, and the way the weapon had to feed to continue to fire and moved to track the target.

Which all sounds well and good...and all I'm asking for is data...rather than people saying the research for the game sucks. The data for the game indicates a ceiling for the 13mm of 13,000' and lo and behold the first site I check that appears to use reputable sources indicates that the effective ceiling was 13,000'.

I have however found some data which would place the combat effective range for the 13mm at 4950'.

The source - US Technical Mission to Japan
The data -
Maximum range - 6550yds (19650') at 50deg
Maximum Ordinate - 4350yds (13050') at 85deg
Maximum Effective range - 1650yds (4950')

So the question is what would be an appropriate max ceiling rating in the game? 19,000 , 13,000 or 4,950? Afterall targeting may drop off after 4950' but there are still "effective" rounds being thrown up to 13,000'....

[greg_slith]

Since when do the trigger pullers have any say in the ops they have to complete? [:D] High altitude/precision bombing was the Holy Grail of the airdales. It didn't work real well in the Pacific. The air bosses only changed their minds when thing really went to hell over Japan. Jet stream too much for the Norden to compensate for kinda thing. So a mean SOB like LeMay says lets go REAL LOW. Knowing his crews would not be keen with this he let them do it at night. Night time provided protection- not fron flak as much as from fighters. Especially since almost all of the MG's were yanked from the bombers. Losses were so low that this became the prefered method. It was true when there was no threat of fighter interception, also.

[Helpless]

ORIGINAL: Big B
I would imagine that if that is the case, the Allied flyers would have found out fairly quickly where the safest altitudes were - they were the ones getting shot at, and would be the first ones to figure out where the flak is least effective...

For quite a long period of time main headache for Allies bombers is Japanese CAP, which might be very deadly at the attitude of THE (possible) GAP.

[Nikademus]

after reading Westermann, I no longer feel thats the case

[m10bob]

Go to the bottom of this Japanese site for some stats on Japanese AA guns:

http://www3.plala.or.jp/takihome/artillery.htm

[herwin]

ORIGINAL: Ron Saueracker

ORIGINAL: treespider

Another matter that has not been addressed and partly explains why attacks were launched at much higher Altitudes IRL is the complete absence of barrage ballons in the game...

Yep, no barrage baloons but no anti-torpedo defences in harbors either, yet 2E bombers can use torps vs ships in port despite both a lack of historical examples of 2Es doing so, especially given the limiting confines of most harbors.[8D] Barrage baloons and net defences would be most welcome IMO.

The torpedo nets would be easy to add except that a number of historical torpedo attacks on ships in harbour would be nerfed.

[herwin]

ORIGINAL: Nikademus

i'd settle for just removing the min alt rule. 100 lines of algorithm is SO 20th Century..... [;)]


However....it might be useful to add disruption to the bombers aim from flak.

The min alt rule is real. To model the effectiveness of AA, you integrate between a minimum distance defined by the maximum angular rate the gun could sustain and a maximum effective distance.

[mikemike]

ORIGINAL: Nikademus


Thats why 2E's took over (the skip bombing in the Pac)....a far better platform...rugged, but more nimble and less of a target. Bergerud states that AA in general is far underestimated during the pac war, same as it was for in Europe....

...

LeMay was able to exploit Japan's lack of technology for night time AA defense and could lower the alt for night raids using incendiaries. German night defenses would have made such a tactic far more costly.

I remember reading somewhere that on the first sorties of the Douglas A-26 (later called the B-26) against German targets, which must have been just months before VE-Day, eleven of the twelve aircraft sortied were shot down, obviously by AA fire. If the story is true, I wonder if the crews thought they were exploiting some kind of an AA gap?

[Apollo11]

Hi all,

So... is threre concensus of some sort that there is a problem and that powers to be (i.e. our gallant programmers Don, Joe and Michael [&o][&o][&o]) would look into it someday?


Leo "Apollo11"

[String]

ORIGINAL: Apollo11

Hi all,

So... is threre concensus of some sort that there is a problem and that powers to be (i.e. our gallant programmers Don, Joe and Michael [&o][&o][&o]) would look into it someday?


Leo "Apollo11"

I think the "problem" here is that most numerical values are very strict in the game.. some slight variations (5% perhaps) in all values dependant on experience etc would be nice. Such as airplane max altitude, AA max altitude, gun penetration values etc.