Just Schmidt
Senior Airman
I've been given this some thought over the years, and though (or because) i have not formed a firm opinion, I try to make my thoughts clear in this thread; though it was prompted by the discussion of Ju 89's over Britain and the hypothetical effectiveness of their defensive armament, I think it proper to open a new. My sources are mostly widely scattered threads in this forum over the years, I hope my interpretations will not offend anyone though of course I do not agree with everybody, but warmly welcome any corrections or other comments on potential weak links in my chain of argument. Apologies in advance if I only manage to state the obvious.
The title is loose, i had thought about 'effectiveness of DA', but that invites a narrower discussion of what we mean by effective. I once read somewhere that the remote guns on the Me 410 became effective, but certainly it was not enough to defend against allied escort fighters. Here it probably meant that the arrangement overcame technical troubles. As pointed out several times, defensive armament is not there to shoot down enemy fighters, but to protect the plane itself from being shot down. That it might do by simply installing in the attacker a healthy respect, though this is hard to quantify. How do we prove that aircraft x was NOT shot down because it carried a scare gun? Another thing is effectiveness over averages, while the defended plane may not be invulnerable, the fleet itself will (potentially) take significant fewer losses over time. A shot down fighter does of course help more in this perspective than one who slinked away to fight another day. A third kind of effectiveness is forcing the enemy to apply countermeasures. Though the B-17 was a failure (sic!) in its intended role as an UNESCORTED daylight bomber - the concept itself but not the aircraft being wrong - one effect of its progressively increasing defensive armament was to make die Luftwaffe increase the offensive armament of its fighters and using stand off tactics with for example rockets in order to break up the defensive boxes. These heavily armed fighters were then more vulnerable to escorting fighters where and when these turned up. Here the attritional game does again make matters difficult to measure. If a heavy fighter shoots down bomber x, but is itself shot down by fighter y so it does not shoot down bomber z the next day, bomber x and fighter y successfully combined to protect bomber z. Again what effective means is not altogether unproblematic.
At the extremes we have the unarmed fast bomber and the slow heavily (turret) armed bomber in large defensive formations. Loss rates can be deceptive, as low rate of the Mosquito is partly explicable by the majority of allied bombers being armed. had they all been mosquitos, die Luftwaffe could have made do with lightly armed fighters, increasing both chanse of interception and ability to dogfight or evade escorting fighters. And would have been spared casualties to the defensive fire. In favour of the bomber, a higher percentage of payload would be offensive, and mission time shorter, a four-engined 'mosquito' would fly fewer missions for the same load, and spend less time in enemy airspace. As a side note, perhaps strategy would be changed, so instead of massed attacks small groups attacked a large number of targets, so as to greatly increase demands on ground control. Guessing the target beforehand would also be more difficult if there was 20 targets. A problem for the offense is that immunity often is a combination of height and speed, and bombing is less accurate the higher you fly. Of course the RAF demonstrated late in the war whet kind of precision can be achieved under cover of darkness with help of technology, and die Luftwaffe how that cover could be diminished.
The other extreme, in ww2 at least, was the USAAF's daylight attacks, where loss of performance was accepted for steadily increasing defensive armament, at least for the B-17 over Europe. The principle to put a gun and preferably a turret wherever possible. I already stated above to what extent I think their armament was effective, While I find it obvious that powered turrets were far more effective than hand held guns, I am somewhat suspicious of the neat formulas (fx four times as effective), but at the speeds bombers cruised at, I suspect the waist guns on B 17 and B 24 were next to useless, except as morale boosters. I may be wrong, but probably the increased load and fewer crew members would have justified their removal. As to the principal effect of the turrets, I found the two old threads about turret fighters interesting. If they did not make fast manouverable aircraft viable, I fail to see how a bigger slower aircraft ever could be adequately defended by these. Of course, a large formation of bombers flying steady, would make the task easier for the gunners. Another thing is that, I assume, a fighter attacking head on or from dead astern, will be an easier target than one sipping past the bomber. Which leads to the middle of the continuum.
That is the somewhat faster bomber with some defensive armament, to at least install some respect in attackers. On the face of it, it appears to make sense, but arguably it is what die Luftwaffe tried to do (or was forced to do) most of the time, even the He 111 and Do 17 were relatively fast when they first entered service. Another way of looking at it is that it's neither here nor there. My reckoning is that a stern chase will present the defensive gunner with an easier task, as the two aircraft (if the speed difference isn't too large) are heading in roughly the same direction, or along the same axis. In the middle 80's I played a computer game where I was the tail gunner in a Lancaster, shooting down dosens or hundreds of night fighters on each mission, the point being that you practically only had to sight in two dimensions. No doubt you was not a mid turret gunner shooting in all directions, as that would have required more computational power than was then available for an ZX Spectrum, the amount of calculation being the point, not any postulated realism in the game itself. Anyway it appears to me that there must be something lacking (if only speed in the bomber), as otherwise aircraft as Do 217 and Ju 188 ought to have done better. or maybe raids of hundreds at a time would have made loss rates acceptable? (An acceptable loss rate is not a fixed percentage, but depends on available resources, the percieved importance of the mission(s) and general preparedness to sacrifice men and material). I always wondered why they put fixed defensive guns on the Ar 234, possibly because they at the time of their design did not feel certain it would be faster than future allied fighters? Indeed their margin of speed was not great.
Another thing I've found strange is the obsession with blind spots, of which one example is the tail turret on Ju 188 and derivatives. dead astern should be decent enough (and arguably 'easily' achievable with twin tail booms), provided the difference in speed isn't large. Thus a blind angle behind and below would only be problematic if the intercepting fighter was fast enough to attack on the climb, so to speak. There is of course the situation where an interception can be planned in advance, and the interceptor waits at higher altitude. But that should give them little more than one pass. Equally aircraft in other positions relative to the bomber would not stay there long, except (ironically) a turret fighter flying parallel course. A relevant middle position from rl is of course fixed slanted guns. But Schräge Music was mostly effective when the target was unawares of the attack, a pair of eyeballs (or of course rader), would probably have been nearly as good a bet for RAF's night bombers, and add far less weight and drag. which indicates that having guns able to reach all angles will cost a lot in other performance stats. Suddenly the converted bomber with rockets or 50 millimeter guns can catch you again.
If there is a question here, it is perhaps whether the Germans (and to some extent the Japanese, their army bombers were pretty fast especially compared to their own fighters) had the right or at least a workable idea, had they possessed enough resources to build and operate enough bombers AND sufficient long range fighter escorts. Or would the best be 'mosquitos' escorted by fighters? Or the historical situation where heavily armed and eventually escorted bombers forced unbearable attrition on die Luftwaffe while mosquitos could exploit a niche that the enemy simply could not devote resources to cover? the only thing I'm pretty sure of is that, for an effective bomber offensive, a long range escort fighter (or at least an equal range escort fighter) was indispensable.
All the above implies extended bombing campaigns of 'strategic' nature, but that is not the only bombing mission. The defensive guns on Stukas and sturmoviks meriting other considerations. And then there is defensive guns on fighters and maritime patrol, to mention two extremes. As it is a luxury rarely affordable to design an aircraft for just one narrowly defined mission, there is also versatility to consider.
I really hope some of you will chime in with your wast knowledge, general or specialized. All comments are much appreciated!
The title is loose, i had thought about 'effectiveness of DA', but that invites a narrower discussion of what we mean by effective. I once read somewhere that the remote guns on the Me 410 became effective, but certainly it was not enough to defend against allied escort fighters. Here it probably meant that the arrangement overcame technical troubles. As pointed out several times, defensive armament is not there to shoot down enemy fighters, but to protect the plane itself from being shot down. That it might do by simply installing in the attacker a healthy respect, though this is hard to quantify. How do we prove that aircraft x was NOT shot down because it carried a scare gun? Another thing is effectiveness over averages, while the defended plane may not be invulnerable, the fleet itself will (potentially) take significant fewer losses over time. A shot down fighter does of course help more in this perspective than one who slinked away to fight another day. A third kind of effectiveness is forcing the enemy to apply countermeasures. Though the B-17 was a failure (sic!) in its intended role as an UNESCORTED daylight bomber - the concept itself but not the aircraft being wrong - one effect of its progressively increasing defensive armament was to make die Luftwaffe increase the offensive armament of its fighters and using stand off tactics with for example rockets in order to break up the defensive boxes. These heavily armed fighters were then more vulnerable to escorting fighters where and when these turned up. Here the attritional game does again make matters difficult to measure. If a heavy fighter shoots down bomber x, but is itself shot down by fighter y so it does not shoot down bomber z the next day, bomber x and fighter y successfully combined to protect bomber z. Again what effective means is not altogether unproblematic.
At the extremes we have the unarmed fast bomber and the slow heavily (turret) armed bomber in large defensive formations. Loss rates can be deceptive, as low rate of the Mosquito is partly explicable by the majority of allied bombers being armed. had they all been mosquitos, die Luftwaffe could have made do with lightly armed fighters, increasing both chanse of interception and ability to dogfight or evade escorting fighters. And would have been spared casualties to the defensive fire. In favour of the bomber, a higher percentage of payload would be offensive, and mission time shorter, a four-engined 'mosquito' would fly fewer missions for the same load, and spend less time in enemy airspace. As a side note, perhaps strategy would be changed, so instead of massed attacks small groups attacked a large number of targets, so as to greatly increase demands on ground control. Guessing the target beforehand would also be more difficult if there was 20 targets. A problem for the offense is that immunity often is a combination of height and speed, and bombing is less accurate the higher you fly. Of course the RAF demonstrated late in the war whet kind of precision can be achieved under cover of darkness with help of technology, and die Luftwaffe how that cover could be diminished.
The other extreme, in ww2 at least, was the USAAF's daylight attacks, where loss of performance was accepted for steadily increasing defensive armament, at least for the B-17 over Europe. The principle to put a gun and preferably a turret wherever possible. I already stated above to what extent I think their armament was effective, While I find it obvious that powered turrets were far more effective than hand held guns, I am somewhat suspicious of the neat formulas (fx four times as effective), but at the speeds bombers cruised at, I suspect the waist guns on B 17 and B 24 were next to useless, except as morale boosters. I may be wrong, but probably the increased load and fewer crew members would have justified their removal. As to the principal effect of the turrets, I found the two old threads about turret fighters interesting. If they did not make fast manouverable aircraft viable, I fail to see how a bigger slower aircraft ever could be adequately defended by these. Of course, a large formation of bombers flying steady, would make the task easier for the gunners. Another thing is that, I assume, a fighter attacking head on or from dead astern, will be an easier target than one sipping past the bomber. Which leads to the middle of the continuum.
That is the somewhat faster bomber with some defensive armament, to at least install some respect in attackers. On the face of it, it appears to make sense, but arguably it is what die Luftwaffe tried to do (or was forced to do) most of the time, even the He 111 and Do 17 were relatively fast when they first entered service. Another way of looking at it is that it's neither here nor there. My reckoning is that a stern chase will present the defensive gunner with an easier task, as the two aircraft (if the speed difference isn't too large) are heading in roughly the same direction, or along the same axis. In the middle 80's I played a computer game where I was the tail gunner in a Lancaster, shooting down dosens or hundreds of night fighters on each mission, the point being that you practically only had to sight in two dimensions. No doubt you was not a mid turret gunner shooting in all directions, as that would have required more computational power than was then available for an ZX Spectrum, the amount of calculation being the point, not any postulated realism in the game itself. Anyway it appears to me that there must be something lacking (if only speed in the bomber), as otherwise aircraft as Do 217 and Ju 188 ought to have done better. or maybe raids of hundreds at a time would have made loss rates acceptable? (An acceptable loss rate is not a fixed percentage, but depends on available resources, the percieved importance of the mission(s) and general preparedness to sacrifice men and material). I always wondered why they put fixed defensive guns on the Ar 234, possibly because they at the time of their design did not feel certain it would be faster than future allied fighters? Indeed their margin of speed was not great.
Another thing I've found strange is the obsession with blind spots, of which one example is the tail turret on Ju 188 and derivatives. dead astern should be decent enough (and arguably 'easily' achievable with twin tail booms), provided the difference in speed isn't large. Thus a blind angle behind and below would only be problematic if the intercepting fighter was fast enough to attack on the climb, so to speak. There is of course the situation where an interception can be planned in advance, and the interceptor waits at higher altitude. But that should give them little more than one pass. Equally aircraft in other positions relative to the bomber would not stay there long, except (ironically) a turret fighter flying parallel course. A relevant middle position from rl is of course fixed slanted guns. But Schräge Music was mostly effective when the target was unawares of the attack, a pair of eyeballs (or of course rader), would probably have been nearly as good a bet for RAF's night bombers, and add far less weight and drag. which indicates that having guns able to reach all angles will cost a lot in other performance stats. Suddenly the converted bomber with rockets or 50 millimeter guns can catch you again.
If there is a question here, it is perhaps whether the Germans (and to some extent the Japanese, their army bombers were pretty fast especially compared to their own fighters) had the right or at least a workable idea, had they possessed enough resources to build and operate enough bombers AND sufficient long range fighter escorts. Or would the best be 'mosquitos' escorted by fighters? Or the historical situation where heavily armed and eventually escorted bombers forced unbearable attrition on die Luftwaffe while mosquitos could exploit a niche that the enemy simply could not devote resources to cover? the only thing I'm pretty sure of is that, for an effective bomber offensive, a long range escort fighter (or at least an equal range escort fighter) was indispensable.
All the above implies extended bombing campaigns of 'strategic' nature, but that is not the only bombing mission. The defensive guns on Stukas and sturmoviks meriting other considerations. And then there is defensive guns on fighters and maritime patrol, to mention two extremes. As it is a luxury rarely affordable to design an aircraft for just one narrowly defined mission, there is also versatility to consider.
I really hope some of you will chime in with your wast knowledge, general or specialized. All comments are much appreciated!
