Bomb sights for light bombers.

[Siegfried]

Spring 1944. Savio River bridges in Italy.
P-47. No flak. 50% hit within 180 feet of target. 30 bombs required for 1 hit.
P-47. Medium flak. 50% within 300 feet. 84 bombs required for 1 hit.
P-47. Heavy flak. 50% within 420 feet. 164 bombs required for 1 hit.

Sending an entire P-47 Fighter-Bomber Group to score a single bomb hit on a bridge or other such target is crazy. Why didn't we provide them with a proper bomb sight so they could put the P-47s heavy bomb load (sometimes 2 x 1,000 lb) on target?

I don't think its too difficult to build a toss bombing sight.

You have a 3 dimensional conical cam encoding ballistic data for level flight.
Rotate in speed, slide along for current altitude, output of the cam is
bomb lead, tells you where the bomb is going to hit.

Then you a second cam with the same data for say a 45 degree dive.

If the bomber is in a 22.5 degree dive you do a weighted average of the two cams.

You now have impact point for any speed, altitude and dive angle, which could be used to adjust a recticle.

Better still have a mechanism to latch in and keep track of target during a pullup so
that when the tracking mechanism and impact point mechanism coincide (electrical contact)
the bomb is tossed.

When attacking tanks FW 190 just slid the bomb along the ground with a time delay fuse, quite accurate apparently.

 

[gorizont]

I don't think its too difficult to build a toss bombing sight.

Maybe not too difficult but it seems to me that such devices was started to be installed on US aircrafts only after WWII.

From "Aircraft Profile 150":
"Forty - eight F4U-4 aircraft mounted the AN/ASG-10 Bomb Director Mk1 Mod1 "toss bombing" equipment.
While in level flight prior to dive attack, the AN/ASG-10 power was switched on and the gyros caged and uncaged. After entering the dive with proper sighting allowences set on the gun sight, the bomb release was pressed. At the proper point in the dive, the indicator light would come on for the pull-out to be begun. During pull-out the bomb was automatically released to hit the target."

according to inks I have found tests were completed not earlier than in July 1945:
http://oai.dtic.mil/oai/oai?verb=getRecord&metadataPrefix=html&identifier=AD0492160
TYPE TEST OF AN/ASG-10.
Corporate Author : NAVAL RESEARCH LAB WASHINGTON DC
Personal Author(s) : Fuller, I. W. ; Burnett, M. L.
Report Date : 02 AUG 1945
Abstract : The AN/ASG-10 is a 'Toss-Bombing' director. Its purpose is to enable aircraft to execute glide bombing attacks from increased altitudes (approximately 1700 to 11,000 feet) with a high degree of accuracy. The results of the type tests show that the equipment will work satisfactorily over a temperature range of minus 30 C to plus 50 C at low humidities. If the equipment is to be operated under humid conditions, the wire used in all the units and all cables should be vinylite covered wire. It is also desirable to treat the MPI potentiometer and the test switch so that humidity will not give low leakage resistance.

Maybe so late appearence of such a system on US single-engined single-seat aircrafts was due to US heavy engagment in rockets design. They prefered that type of aircraft weapons and rather late found out that rockets even Tiny Tim couldn't allow to hit all the type of targets. Just a oversight.

 

[Siegfried]

This is more or less how the TSA-2D worked. Some were used on Me 262. They worked best on jets because they made use of an accelerometer during the pullup to keep track of the sudden altitide change whose variable resister picked up vibration from the piston engine; appropriate filtering hadn't been developed yet.

The German dislike for solid propellants in part stems from shortages of propellant
chemicals (glycol?) which were needed for explosives and their apparent inaccuracy.
Nevertheless they did develop them, they were to use a cluster of 15 or so hollow charge warheads for AT use.
"Fleischer: German air dropped weapons" has a few pics.

 

[davebender]

That only applies to large rockets such as the V-2. The R4M FF rocket used Diglykol solid fuel. So did the X-7 wire guided AT missle. Panzerfaust rocket motors used low tech compressed black powder.

 

[parsifal]

Spring 1944. Savio River bridges in Italy.
P-47. No flak. 50% hit within 180 feet of target. 30 bombs required for 1 hit.
P-47. Medium flak. 50% within 300 feet. 84 bombs required for 1 hit.
P-47. Heavy flak. 50% within 420 feet. 164 bombs required for 1 hit.

Sending an entire P-47 Fighter-Bomber Group to score a single bomb hit on a bridge or other such target is crazy. Why didn't we provide them with a proper bomb sight so they could put the P-47s heavy bomb load (sometimes 2 x 1,000 lb) on target?

Thats intersting. Thought it might be worthwhile to compare with the hits scored by the LW against the illustrious 10 jan '41. At the time of the first strike against her, Illustrious was steaming at about 25 knots, but in a relatively straight line, because she was launching and receiving aircraft (this did cease as the attack developed. There were no defending fighters and flak I would described as light to moderate. The target was about 700 feet long by 50 feet wide (roughly) The first attack was by torpedo bombers on the Battle Fleet, in which torpedoes missed after avoiding action had been taken. The second, which occurred at about 1235, was carried out by 25 or more Ju 87 and about 17 ju 88 dive-bombers which attacked with great determination and skill, by elements of Geislers naval attack corps. .

In this attack H.M.S Illustrious was severely damaged as a result of 6-direct bomb hits and several near misses, which caused fires and disabled her steering gear. Her casualties were 83 killed, 60 seriously and 40 slightly wounded, including several officers. H.M.S. Warspiie also sustained slight damage from a near miss. During this attack one Fulmar and one Swordfish were shot down, their crews being saved, and two enemy aircraft were shot down by gunfire.

The Ju 88s had a bombload of up to 6600 lbs, but in practice tended to carry 2000 lbs internal and 1100 lbs external. the Ju87Rs that were also present were the long range version of the Stuka would normally carry a 551lb bomb on the centreline plus 4 additional small bombs under the wings (however i doubt these were being carried, except if they were anti-personnel bombs). I know that the ju88s wrere carrying 1000 pounders and 500 pounders, so the likely total carried by the strike could be as high as 17 1000 pounders, and 59 x 500 pounders.

Putting all that together thats a total of 76 bombs dropped for a total of 6 hits. Thats pretty good shooting by the LW. however, in the hours after that initial attack, there was a further strike by about 40 aircraft, and another the next day by 70 German bombers (the majority D/B) These two additional raids manage to score an additional two hits. So, overall, for the committment of 150 aircraft a total of 9 hits were achieved. The majority of those aircraft were either level bombers or Ju88 divebombers, though there were a substantial number of Ju-87s involved. The Ju87s were considered by far to be the most deadly and accurate naval bomber available to the Germans. Anyway, I estimate that those 150 bombers would have dropped around 350 bombs at least to achieve 9 hits, mostly at low altitude, mostly against a stationary target, mostly with little fighter cover and moderate flak protection. thats a hit to miss ratio of 2.5%.

That was by aircraft with bomsights and well trained crews, against a target at something like 10 time the area of the bridge you mentioned. if we assume a target 10x the size of the bridge, that could be interpreted to mean that a LW bomber force attacking that same bridge might hit the bridge once per 400 sorties......

Kinda brings your criticism of the p-47 forces back into perspective i think, and debunks the claim that bombsights make for accurate bombing, sorry, it does nothing of the sort. More than anything for a tactical bomber operating at low level it gets down to pilot skill and bombing conditions at the time....things like weathyer, flak, enemy fighters and the like

 

[gorizont]

Thats intersting. Thought it might be worthwhile to compare with the hits scored by the LW against the illustrious 10 jan '41. At the time of the first strike against her, Illustrious was steaming at about 25 knots, but in a relatively straight line, because she was launching and receiving aircraft (this did cease as the attack developed. There were no defending fighters and flak I would described as light to moderate. The target was about 700 feet long by 50 feet wide (roughly) The first attack was by torpedo bombers on the Battle Fleet, in which torpedoes missed after avoiding action had been taken. The second, which occurred at about 1235, was carried out by 25 or more Ju 87 and about 17 ju 88 dive-bombers which attacked with great determination and skill, by elements of Geislers naval attack corps.

Yes, but you forgot to mention, that the Brits forces were "the main forces of the Mediterranean Fleet, consisting of H.M. Ships Warspite and Valiant with H.M.S. Illustrious and 7 destroyers", and all their AA guns repulsed the attacks not only Illustrious ones.
I suppose that she hardly hadn't made evasive manuevers at the moment of dropping bombs at her - at the aproaching of the germans she had to manuever so far as at the moment she hadn't launch a big group of aircrafts.
I'm sure that you have mistaked by writing that there had been no light flaks. She had since 1940 16 × QF 4.5 inch naval gun (eight × two-barreled) and 48 x QF 2 pounder naval gun (6x eight-barreled) - so she alone had got six "octopuses" - and there had been some at other ships of the tactical force.
Valiant which AA guns fired at LW dive-bombers too had 20 x QF 4.5-inch dual-purpose guns (10 x 2), 32 QF 2-pounder anti-aircraft guns (4 x eight-barreled); 16 x .5-inch machine guns : (4 x 4)
Warspite had 8 × 4 inch Mk XVI anti-aircraft guns (4×2), 32 × 2 pounder anti-aircraft guns (4×eight-barreled), 4 × quadruple 0.5 cal machine guns
About "no fighters" - "During this attack one Fulmar and one Swordfish were shot down, their crews being saved, and two enemy aircraft were shot down by gunfire." As far as I can see - at least a few fighters were in the air.

By the way In 1941 Ju-87 and -88 had Revi-12 installed on them for dive-bombing.

But I have to mention that at the end of war attacks on heavy ships became more difficult - besides more capable CAPs for Allied navy force light AA became much more numeruos (up to handred and a half barrels in up to about 50 mountings, for instance HMS Howe in 1945 had 10 × 14 inch guns, 16 × 5.25 inch guns, 32 × 2-pounder anti-aircraft guns, 14 × 40 mm Bofors AA guns, 65 × Oerlikon 20 mm guns), so in 1941 chances to hit for example Brit ships were much more higher.

I wonder how many flaks defended Savio River bridges. Just for comparison.

 

[Siegfried]

Thats intersting. Thought it might be worthwhile to compare with the hits scored by the LW against the illustrious 10 jan '41.

This date preceded the introduction of the Stuvi 5b with BZA computer that that made it possible to dive bomb accuratly at shallow angles (eg 30 degrees or less), many Ju 88s apparently had their dive brakes removed which must had added to their speed. It also likely precedes the Lotfe 7 level bombing sight. I think early 1942 was the introduction date for both bombsights.

Ju 88's would mostly be releasing their bombs simultaneously or in short stings. Hitting a moving target can be difficult, it requires special training which the Ju 87 pilots had to develop but only some had.

 

[parsifal]

RN AA despite the heavy number of tubes in the was not all that effective due to a number of factors. The fire control mechanisms used by the Brits was faulty which made it less effective than it could be. This was especially true when the targets were making frequenbt changes to altitudfe and/or speed, which is [recisely what happened in the battle. FKX formed a rough clover leaf around the carrier and proceeded to attack from many different directions and made constant changes to altitude speed and direction of attack. The range of the 2 pdr was so limited that it really only was a point defence weapon, meaning that a ship could only provide very limited fire support to nearby ships. The fire of the destroyers was limited by the lack of a fully Dual Purpose main armament (and in any case was not available at all during this battle...neither were the cruisers) . Norman Polmar in his description of the battle gives a good exlanation of what was happening. It is theoretically possible to claim heavy flak, but in reality it was quite light and certainly inneffective.

Compared to the barrages that could be put up later in the war, and the the accuracy of that AA fire, it is valid to describe the AA fire as light and inneffectivefor the first attack. Moreover, not all of the limited firepower that was available could be directed to the LW bombers. It is often forgotten that the LW was supported by a torpedo attack at the same time as the bombing attacks were delivered so this enabled the Germans to line up and deliver their attacks at a rather leisurely pace. There were also other aircraft in the vicinity that did not target the carrier....

I am also fairly sure that the TG was on rationed ammunition because of where it was at the time of the attack, and because the fleet had been under more or less continuous attack all morning and more generally since January 8th.

Lastly, the actual dispositions of the escort at the time of the attack further restricted the amount of supporting AA fire that could be put up in defence of the carrier. At the time of the attack, all three cruisers were more than two miles from the carrier, assisting a destroyer that was experiencing mechanical difficulties. The two battleships were in position, but they were also tasked to provide cover fire for the merchantmen they were escorting so they were not as close to the carrier as they should have been . In any event, the battleships came under attack from 10 stukas themselves, whilst 42 or so attacked the carrier. This meant that at the very time they should have been supporting the carrier, they were busy also defending themselvesMoreover the att

In the whole attack, a total of 5 LW aircraft were shot down by aircraft and AA. It has been estimated that AA fire accounted for three of these losses were from the AA guns. Compared to losses inflicted later in the war, this was a light toll. Sth Dakota at Snata Cruz, for example is credited with no less than 12 aircraft in a single day by herself, against a similar number of attackers

 

[parsifal]

This date preceded the introduction of the Stuvi 5b with BZA computer that that made it possible to dive bomb accuratly at shallow angles (eg 30 degrees or less), many Ju 88s apparently had their dive brakes removed which must had added to their speed. It also likely precedes the Lotfe 7 level bombing sight. I think early 1942 was the introduction date for both bombsights.

Ju 88's would mostly be releasing their bombs simultaneously or in short stings. Hitting a moving target can be difficult, it requires special training which the Ju 87 pilots had to develop but only some had.

Regardless of whether the LW a/c had bomsights fitted or not, or had older style bomsights, with the exception of PQ17 I cannot think of a more accurate attack made on the RN during the war.


I agree that hitting a moving target is hard, but it was less hard for the Germans on that day. At the time of that attack, Illustrious was steaming in close escort to a supply convoy and had just completed her flying operations. These two elements to her disposition restricted her speed and her ability to manouvre.

Your comment about lack of proper training for FKX pilots is only partially true. Ther may have been a few new recruits here or there that lacked adequate training, but overwhelmingly FKX was a well trained and experienceed unit. It was the main antishipping weapon of the LW,. The unit had been responsible since the outbreak of the war for dispatching roughly 700000 tons of shipping and many Allied. It was THE premier anitshipping unit in the LW arsenal.

 

[davebender]

What sort of comparison is that? Hitting a maneuvering naval vessel is much more difficult then hitting a target on land. Naval AA fire is normally a lot heavier too.

Do we have historical records of P-47s attempting to bomb a warship steaming at 25 knots?

 

[davebender]

The didn't always drop bombs on maritime targets. He-111s and Ju-88s sometimes carried torpedoes for naval attack. They also employed skip bombing from an altitude of 45 meters, most famously at Bari, Italy during late 1943.

 

[Siegfried]

Regardless of whether the LW a/c had bomsights fitted or not, or had older style bomsights, with the exception of PQ17 I cannot think of a more accurate attack made on the RN during the war.

The blitz on HMS Illustrious 70 years ago - timesofmalta.com
"The Luftwaffe returned after refueling rearming in Sicily to give the final blow. The fleet went to Illustrious' aid put up a heavy barrage. Fulmars from Illustrious fought to save the ship retired to Malta to refuel rearm to again return to the fight shoot down at least 5 Stukas. She was still 40 miles from Malta."

It seems the Illustrious was rather heavily defended and quite mobile during the second attack in which she was heavily defended by the AAA of other ships. The presence of so much AAA and fighters would have spoiled the aim of the bombers. Ju 88's were not capable of the vertical dive of a Ju 87 and at the time lacked the computing bombsight so much less accurate with only standard sights. The Luftwaffe had to learn to attack moving ships, it had trouble at Dunkique.

"HACS" the "High Angle Control System" had limitations as a AAA director but it was repeatedly modified so that around 1940 (from wiki)

Tachometric and radar additions:

"The RN moved quickly to add true tachometric target motion prediction and radar ranging to the HACS by mid 1941. The RN was the first navy to adopt dedicated FC AA radars. However the system, in common with all WW2 era mechanical AA fire control system still had severe limitations as even the highly advanced USN Mk 37 system in 1944 needed an average of 1,000 rounds of 5-inch ammunition fired per kill.[22] In 1940 the Gyro Rate Unit (GRU) was added to the HACS system, an analogue computer capable of directly calculating target speed and direction,[23] converting the HACS into a tachymetric system.[24][25] Also in 1940, radar ranging was added to the HACS.[26] The GRU and its associated computer, the Gyro Rate Unit Box (GRUB) no longer assumed straight and level flying on the part of the target. GRU/GRUB could generate target speed and position data at angular rates of up to 6 degrees per second, which was sufficient to track a 360 knot crossing target at a range of 2000 yards"

 

[Siegfried]

The didn't always drop bombs on maritime targets. He-111s and Ju-88s sometimes carried torpedoes for naval attack. They also employed skip bombing from an altitude of 45 meters, most famously at Bari, Italy during late 1943.

The Germans didn't have good air dropped torpedoes, this is one area in which the Italians were the world leaders, so the Germans resorted to using Italian torpedoes.

 

[gorizont]

The Germans didn't have good air dropped torpedoes, this is one area in which the Italians were the world leaders, so the Germans resorted to using Italian torpedoes.

I suppose from the start to 1944 the world leader were Japanese not Italians.
As far as I know Germans rejected of pure Japanese aerial torpedo design as difficult for maintanence (they recieved from Japan several dozens of thier Type 91 airial torpedoes as far as I remeber) but used a principal of roll control originally implemented in aerial torpedo design by japanese during both air and water paths of trajectory in late-war mods of F5B.
But anyway Italian aerial torpedoes up to middle of the war were of a better design and capability than Germans (of Norwegian origin).

 

[gorizont]

The didn't always drop bombs on maritime targets. He-111s and Ju-88s sometimes carried torpedoes for naval attack. They also employed skip bombing from an altitude of 45 meters, most famously at Bari, Italy during late 1943.

Early at war up to 1941 he-115 was the main torpedo - bomber of LW. Germans started to improve their torpedoes and produced more capable torpedo-bombers too late and not in suffucient numbers.
Skip bombing was a prefereble method of attack by Condors (I suppose from 1940) but in 1941 Germans abandoned it due to rather heavy losses among FW-200's despite of its effectiveness. Not complitely but sure as standart practice.

 

[Grampa]

Erik Wilkenson developed the m/42 bombsight for saab b17 1942 that alloved to do tossbombing on the target whit great accurate. in 1952 the USA where impressed by the late developed BT-9 and bougt some Bt-9D for there attackplanes. does anyone know whitc plane where equippment whit that device?

Here's a link of swedish sights. sorry but they are in swedish so plz ask me if you have question if there something in there you whanna know about.

Innehll i avsnittet Bevpning

 

[gorizont]

Erik Wilkenson developed the m/42 bombsight for saab b17 1942 that alloved to do tossbombing on the target whit great accurate. in 1952 the USA where impressed by the late developed BT-9 and bougt some Bt-9D for there attackplanes. does anyone know whitc plane where equippment whit that device?

Here's a link of swedish sights. sorry but they are in swedish so plz ask me if you have question if there something in there you whanna know about.

Innehll i avsnittet Bevpning

Thanks for info.
Rather interesting. I learnt a bit info of that in one of Smith's book about dive-bombers and saw a picture of the device in one book from "Aircraft profile" serie (perhaps about Tunnan).
In its first mode I guess BT-2 was a bit inferior to TSA-2D. If input of altitude data was for BT-2 manual for TSA-2D it was automatic from radioaltimeter FuG-101 as far as remember.
But BT- had a strong advanteg over TSA-2D - it development was continued and as for TSA it ended with Germany's defeat.

I wonder the way it calculated. As I guess the devices calculated on the base of data of altitude and angle of dive slanting distance to the point of aim (to the target) and thus continuously calculated by ballistic of a choosed ordnance the distance of dropping and time to that point making corrections of change of height, speed, acceleration and angle of dive by data from accelerometer and stable gyro. But I'm not sure at all.

 

[parsifal]

The blitz on HMS Illustrious 70 years ago - timesofmalta.com

relying on a source like the BBC world history series is not a good basis for historical analysis. Its okay, but not great. I am relying on at least five written sources, chiely Norman Polmars 800 page book on Carrier Warfare in WWII. He devotes nearly 20 pages to this battle, giving and almost blow by blow account. Its at home at this minute, and i am not, but i can check later tonite to confirm details in the following response


"

The Luftwaffe returned after refueling rearming in Sicily to give the final blow. The fleet went to Illustrious' aid put up a heavy barrage. Fulmars from Illustrious fought to save the ship retired to Malta to refuel rearm to again return to the fight shoot down at least 5 Stukas. She was still 40 miles from Malta."

All true enough, but its the omissions that make this statement unreliable. Whereas the attacks at noon had involved only a portion of FKX (and these were the attacks I was referring to incidentally), the air attacks delivered in the afternoon (starting at around 3pm) were delivered by the full force of the Korps. at that time there were 248 a/c attached, plus there were approximately 50-100 RA aircraft involved in the attacks. To be fair, the Axis divided their concentrations into two, one part attacking the convoy and the other concentrating on finishing off the carrier. But then, this division of effort needs to be balanced up by the fact that the defenders also had to split their forces, some to protect the convoy, and some to protect the carrier (which by then had been detached).

In that second attack, Axis losses amounted to 10 A/C. 5 are indeed attributed to the 5 remaining Fulmars providing topcover, by now operating from Malta about 40 miles away. The carrier had suffered a fire in the hangar, that had destroyed 9 Swordfish and all the fighters that were not airborne. Only those that were airborne were able to divert to malta.

Illustrious was just getting underway again. I am not sure of its speed, but it was still manouvering by engines alone. I ahave read reports that her speed in that second attack was about 10 knots. She still had the "Ship Not Under Command" ensign on her yardarm at the time of this attack, which says in spades she was barely underway and barely manouvering

I am unsure if the words chosen in your quote are as careful as i am reading them (ie, am I reading too much into them), but a "barrage" is not directed fire, its the method used when you cannot aim properly. If the Brits were relying on "barrage" fire, they were in deep trouble at the time of that second attack

It seems the Illustrious was rather heavily defended and quite mobile during the second attack in which she was heavily defended by the AAA of other ships. The presence of so much AAA and fighters would have spoiled the aim of the bombers. Ju 88's were not capable of the vertical dive of a Ju 87 and at the time lacked the computing bombsight so much less accurate with only standard sights. The Luftwaffe had to learn to attack moving ships, it had trouble at Dunkique.

Ah agreed, however FKX flyers had been trained to ignore the effects of flak, had developed tactics that maximised their benefit against the known British weaknesses in their AA FC. FKX had been fighting the RN since April 1940, and knew their jobs. Against experienced verterans like that British AA was weak. by the time of the second attacks and the attacks over malta, the defences had been organised and were ready, and proved very effective, thatmuch I can agree with, but also by then, the numbers of aircraft involved in the attacks had greatly increased. Rememeber, the object of this little sub-debate is how the LW compared in terms of accuracy to aircraft not fitted with bombsights. I am saying they didnt make much difference to the accuracy issue.

"HACS" the "High Angle Control System" had limitations as a AAA director but it was repeatedly modified so that around 1940 (from wiki)

Tachometric and radar additions:

"The RN moved quickly to add true tachometric target motion prediction and radar ranging to the HACS by mid 1941. The RN was the first navy to adopt dedicated FC AA radars. However the system, in common with all WW2 era mechanical AA fire control system still had severe limitations as even the highly advanced USN Mk 37 system in 1944 needed an average of 1,000 rounds of 5-inch ammunition fired per kill.[22] In 1940 the Gyro Rate Unit (GRU) was added to the HACS system, an analogue computer capable of directly calculating target speed and direction,[23] converting the HACS into a tachymetric system.[24][25] Also in 1940, radar ranging was added to the HACS.[26] The GRU and its associated computer, the Gyro Rate Unit Box (GRUB) no longer assumed straight and level flying on the part of the target. GRU/GRUB could generate target speed and position data at angular rates of up to 6 degrees per second, which was sufficient to track a 360 knot crossing target at a range of 2000 yards"

Wiki is a source you need to be careful with, though in this case the information concerning technical specs seems okay to me. what is misleading, in the extreme, is the claim that the brits had solved their AA problems for their sghips by 1940, or even by mid 1941. I would recommend that you spend roughly AU$180 in a good reference like campbell, that looks at this in detail. Basically the true picture is this....Britain had indeed identified the shortcomings in its AA systems afloat by mid 1940, following the poor showings in Norway. New ships from the midddle of 1941 on were indeed incoprorating new FC and directors, and in some instances stabilized mounts. older ships also as they could enter refit were being updated to the new standards. but this took time, and even as late as 1944 RN ships were still having difficulty with their AA systems. But anyway, in the case of this battle, Illuistrious had not been updated or refitted since commissioning. Her AA systems, whilst very advanced (relative to other RN units) , did not take on board the newest ideas mentioned in the wiki article. It was basically a 1938 style AA suite, designed with all the inherent flaws in that system. It finished up working adequately, but not outstandingly. The same can be said for the two battleships. I have their refit dates at home, but they too were still using the late 1938ish style of AA FC and weapons fits. I will also need to check at home exactly what support was given to Illustrious whilst she was in Malta...not sure if the BBs stayed with her or not.

To get some idea of the efficiency of the british system compared to the US mk37 system of late 1944, for the Us the estimated number of rounds per kill in 1944 from director controlled fire was about 500 to 1000. For the Brits in 1941, the estimated ammo expended from director controlled fire was about 10x that amount (german AA fire needed approximately 8250 rpk according to Westermann at this time) . That means Brit AA was about a tenth as effective as its US counterpart. They improved that gradually as the war progressed, but in 1941 they had a lot of problems.

One final observation, the article says (erroneously) that things were in hand by 1941....well even on the basis of that flawed article, the combattants would have been operating at a disadvantage. The battle was fought in January 1941, not mid 1941.

 

[Siegfried]

[

Ah agreed, however FKX flyers had been trained to ignore the effects of flak, had developed tactics that maximised their benefit against the known British weaknesses in their AA FC. FKX had been fighting the RN since April 1940, and knew their jobs.

Rememeber, the object of this little sub-debate is how the LW compared in terms of accuracy to aircraft not fitted with bombsights. I am saying they didnt make much difference to the accuracy issue.


Wiki is a source you need to be careful with, though in this case the information concerning technical specs seems okay to me.

The installation of Gyro Rate Unit Boxes, supposedly in 1940, would have improved HACS which previous to this required speed to be estimated and assumed constant height.

Ju 87 were very accurate dive bombers due to the vertical cabillity, Ju 88 were fairly accurate as dive bombers even due to the 45-60 degree capabillity with what amounts to little more than a gun sight with grid markings. However they were receiving AAA from the Illustrious, Nearby escorts and Fairy Fulmar fighters (where were the Bf 109s?) and the carrier was moving, she had steam going to her screws (enough for rudimentary stearing). Had the Ju 88's had the Stuvi 5B with BZA computer its likely they would have been more accurate. Even the Ju 87 was more accurate with this sight.

To put it bluntly, Illustrious was a moving target protected by professional AAA from several ships and escorts. Much harder than hitting a bridge. The Ju 88's, which were the bulk of the attackers had not been equiped with computing bombsights.

Comparing AAA with FLAK rounds to kill given a false impression. The data from Westerman is for a period when Allied jamming had just had a victory and the Germans had not yet had time to counter. It compares older weaker FLAK 8.8cm 18/36/37 guns from 'dads army reserve units' with second rate directors rather than the larger more powerfull 10.5 and 12.8cm guns which achieved 3000 shots to a kill in the same period. The US and UK guns were larger and more pwerfull than the basic 8.8cm (not FLAK 41).

The US by 1943 was widely using proximity fuses at sea by then.

 

[parsifal]

The installation of Gyro Rate Unit Boxes, supposedly in 41, would have improved HACS which previous to this required speed to be estimated and assumed constant height.

But it didnt happen in 1941, for the most part it didnt happen in '42 either. It was fitted mostly after April 43 for the most part as a generalization

Ju 87 were very accurate dive bombers due to the vertical cabillity, Ju 88 were fairly accurate as dive bombers even due to the 45-60 degree capabillity with what amounts to little more than a gun sight with grid markings. However they were receiving AAA from the Illustrious, Nearby escorts and Fairy Fulmar fighters (where were the Bf 109s?) and the carrier was moving, she had steam going to her screws (enough for rudimentary stearing). Had the Ju 88's had the Stuvi 5B with BZA computer its likely they would have been more accurate. Even the Ju 87 was more accurate with this sight.

Whats your source that they were receiving fire from the escort? They were receiving some fire, thats for sure, but not much and not very effective. I have a copy of the Fleet commanders Report (Cunningham) which you are welcome to have a look at, and he definately does NOT say that. In fact, relevantly he says, in his report to his bosses "The dive bombing attacks by German aircraft were most efficiently performed and came as an unpleasant surprise. The results of our A.A. fire were disappointing[/U]. he then goes on to give quite detailed accounts and explantions as to where ships were, what was happening and why the Carrier could not be supported as she should have been. It does pay to do a little research before making claims like that I am afraid

To put it bluntly, Illustrious was a moving target protected by professional AAA from several ships and escorts. Much harder than hitting a bridge. The Ju 88's, which were the bulk of the attackers had not been equiped with computing bombsights.

To put it even more bluntly, she was a moving target, moving slowly, in a slow predictable path, and a target much bigger than a bridge, in near perfect conditions (we do not know the conditions of the P-47 attack). The Ju88s were not the bulk of the attackers, incidentally, more than half the attackers were Ju87s in fact. The AA crews were professional, but the equipment they were using not so good.

So, if you think that computing bombsights would make a difference to bombing accuracy, why is it that this attack on the RN is considered the most accurate, and most efficient ever achieved by the LW on a moving seaborn target, except for PQ17???? Your failing to answer that

Comparing AAA with FLAK rounds to kill given a false impression. The data from Westerman is for a period when Allied jamming had just had a victory and the Germans had not yet had time to counter. It compares older weaker FLAK 8.8cm 18/36/37 guns from 'dads army reserve units' with second rate directors rather than the larger more powerfull 10.5 and 12.8cm guns which achieved 3000 shots to a kill in the same period. The US and UK guns were larger and more pwerfull than the basic 8.8cm (not FLAK 41).

Westermannn does NOT make that comparison or at least, he does not make that comparison on its own or in isolation. he compares overall, he compares specific weapons, he makes the point that in 1941 and 42 the Germans were using fully trained professional flak crews and that their weapons were the best in the world at that time. I dont know if you have even read Wstermann, but he most certainly does NOT say what you are claiming.

I agree that TPK is not such a good measure, but it does provide a surrogate measure of flak effectiveness. It gives us an indication as to how accurate the AA was, but the real measure is how effective the guns were in throwing the attackers off aim.

The US by 1943 was widely using proximity fuses at sea by then.

which has been reckoned to about double AA efficiency. thats not the only thig at work here....the increase in AA efficiency was due to a whole suite of changes that in total added up to a greatly incresed efficiency level. Putting that increased effieiciency level down to one or two factors is the misleading statement, not using a surrogate measure to gauge accuracy.