Defeating Bomber Command

[wiking85]

Tearing around trhe sky at max speed isn't a viable option, endurance would be hit and unless you think 30 mins is good enough for the mission (it isn't) the fact still remains, the Beaufighter had sufficient performance to better the Ju88. In case you think the weight of the radar on the beau would slow it down the Beau carrying a torpedo still went faster and climbed better than a Ju88c.

Which mark of the Beaufighter, the 1944 version or the 1942 one? Which version of the Hercules engine, or the early Merlin engined Beau?

 

[stona]

Beaufighters have to climb to altitude and loiter while searching at multiple altitudes and in all directions looking for the intruders.

No they didn't. That's the whole point of a coordinated GCI and AI radar system. The British night fighters could be vectored to a target by the GCI radar controller, only making the final approach to visual range over the last two miles or so using their AI radar. They didn't need to loiter and they didn't search for intruders at all heights and in all directions, that was done by the GCI radars, each of which could now track several targets.
What sort of altitude would the attacks on assembling or landing aircraft be made? It seems that attacks were made on aircraft 'in the circuit'. It seems unlikely that the Beaufighters would need to get up to a great altitude to find the intruders and they would receive the altitude of their target from the GCI radar controller.

The intruders proved very vulnerable to interception. It was losses over the winter of 40/41 that forced them to suspend the first and last of their three phase operation (attacking aircraft as they took off and returned) and concentrate on the middle phase (interception over the North Sea).
In June 1941 I./NJG 2 made 20 interceptions, 18 of them over the sea. To put those twenty interceptions (not claims and certainly not losses) in perspective, in June 1941 Bomber Command flew nearly 4,000 sorties.
Over land non-radar equipped intruders might find bombers assembling or returning with navigation lights on circling over illuminated airfields making a relatively easy target. Not so over the sea.

Cheers

Steve

 

[mhuxt]

Good info on German intruders in "Intruders Over Britain" by Simon Parry.

 

[parsifal]

The Ju88C did not use radar for intruder operations.

I know, and irrelevant to the issue. Visual or blind, target acquisition at night does not require a fast moving or jinking aircraft. Quite the opposite. It requires a slow moving target operating at normal to low altitudes, flying a straight line searching the sky methoddically.

Intruder operations are notoriously dangerous operations. You need an exceptionally well equipped and high performance aircraft with the very latest detection systems to be any good at it, and no-one except the british possesed that capability until 1944, in the form of the Mosquito. ther is one other element, equally as important as the technology. you need the people with the experience and temperament to undertake these operations. Necessarily this kept the numbers available low for both sides, and rendered intruder ops essentially of nuisance value only until the very end of the war.

.

It used the internal bomb bays for fuel and were a cleaner airframe due to no ventral gondola and an improved nose layout. Ordnance was carried externally. By the time they are over Britain they will be at altitude and speed, which the Beaufighters have to climb to altitude and loiter while searching at multiple altitudes and in all directions looking for the intruders.

This is good for the fairytale or wet dream value and nothing else really. Germany did not mount anything comparable to this until 1942 when a handful of Ju88s were employed in that very role. They had some sucess, with certain exceptionally brave and audacious Night fighter pilots following the bomber streams home and tearing into them as they came in to land basically, but theeir own losses were very heavy as well, when expressed as a proportion of the force structure. as an example three Ju88s operating in the very capacity you describe (albeit carrying bombs) on the 8th March were caught by 5 beafighters in the new night Ranger Patrols (there was no difficulty for British radar to determoine both bearing and height....the difficulty was that once within 3.5 miles of the target the Beaus needed to rely on visual target acquisition, and this often caused them difficulty). On this night, 3 Ju88s were sent, and three were lost. The next night the first German aircraft was lost to a mosquito, again being a Ju88 off Manston. The aircraft was flown by Pilot Officer Arbos of 85 Sqn

Further Intruder operations by the germans were not attempted again until 26th March when a lone Do217 was intercepted and shot down by Hurricanes operating over Einhoven and gilze Rijn. soi confident and skilled were the british fighters by this time they were operating over enemy territory as well, taking the "Intruder " concept to the absurdity that it was. ABeafighter operating in the same role and in the same general area, was lost when it crashed near Morpeth. On the 6th April another Ju88 intruder was intercepted and shot down by a Beafighter in the Thames estuary. A hurricane also operating in this area was damaged on landing

There are no gaps or successes in this period for the Germans. every intruder they sent out was intercepted and either shot down or damaged. no exceptions. Later the Germans got a bit wiser and adopted tactics that made them more successful, but this took time for them to learn the right techniques.


Given also that the British relied on single seat fighters for point defence, similar to the German wild sau ops, and had access to the Spitfire VII very high altitude fighter at this time, ther is absolutely no hope of them being able to get any altitude advantage on a regular basis

 

[stona]

Determining height with radar based on Chain Home was a tricky business. Without going mad with science it depended on comparing signals received by different elements of the receiver at different heights above the ground. It could be done and very accurately by experienced operators. Unlike during the BoB such people were becoming available in numbers by 1941.

British AI Mk III and IV radars showed a target on two CRTs. One for elevation and one for azimuth (left/right). Both showed range (unlike later German systems). It was this that was used in the last 2-3 miles of an interception leading up to a visual attack.
The need for the pilot to control the final stages of an approach, not relying on a commentary from his operator, led to the introduction of a further CRT known as the pilot's indicator, on the AI Mk V system. The pilot could refer directly to this display, a distant ancestor of the modern HUD.

I say again, whereas the night fighter was at the sharp end of the system it did not need stellar performance. It just had to be able to catch the target. It was the system of control and the radars that provided the information for that control which were the most important elements in the coordinated system.

With the help of the GCI chain and improvements in the delivery of Beaufighters and AI radar sets, the number of enemy aircraft destroyed rose during the late winter and spring of 1941. Three were destroyed in January, four in February, twenty-two in March, forty-eight in April and ninety-six in May. Not all these losses were down to radar equipped night fighters. It was these mounting losses which forced I./NJG 2 out over the North Sea and away from mainland Britain. I would suggest that the Luftwaffe's first intruder campaign was far from 'staggering'. It was in fact defeated before it really got going.

Cheers

Steve

 

[Shortround6]

The Ju88C did not use radar for intruder operations. It used the internal bomb bays for fuel and were a cleaner airframe due to no ventral gondola and an improved nose layout. Ordnance was carried externally. By the time they are over Britain they will be at altitude and speed, which the Beaufighters have to climb to altitude and loiter while searching at multiple altitudes and in all directions looking for the intruders.

I seemed to be a bit confused as to what method/s of intruder attack the Germans are supposed to be using.

Following the bombers 'home' and shooting them down as they land with illumination from lit airfields and or landing lights?

Precision bombing from medium-high altitude and high speed? at night?

Most JU 88c did retain the ventral gondola, although in modified form. And you can't have it both ways, you either carry bombs inside and have high performance or you carry them outside and accept the performance loss, at least on the run into the target.

" By the time they are over Britain they will be at altitude and speed" Goes back to just what kind of attack are you planning? the returning British bombers are NOT at altitude and speed having started descending before reaching the British coast. If you are engaging with guns you have descend to where the targets are.

Beaufighters had an endurance (range) roughly 3 1/2 times that of a Spitfire or Hurricane without drop tanks. While standing patrols with Spitfires or Hurricanes made little sense (incoming raid isn't plotted until the standing patrol had used up 1/2 of it's 80-90 gallons of fuel?) the question changes somewhat with the much longer endurance (and slower climbing) Beaufighter. And has been mentioned, the Beaufighters are not doing the searching. They are simply in position to respond quickly to to directions from ground controllers.

 

[stona]

The plan was to attack the bombers taking off, intercept them on their way to and from the continent and attack them again when they were landing. They were to carry bombs to drop on the RAF airfields. Several fields were in fact bombed and strafed.
The plan was VERY optimistic, given that between August 1940 and October 1941 there were rarely more than 20 aircraft available as intruders. There were never more than 30 serviceable aircraft for I./NJG 2 at Gilze-Rijen.
Cheers
Steve

 

[wiking85]

With the help of the GCI chain and improvements in the delivery of Beaufighters and AI radar sets, the number of enemy aircraft destroyed rose during the late winter and spring of 1941. Three were destroyed in January, four in February, twenty-two in March, forty-eight in April and ninety-six in May. Not all these losses were down to radar equipped night fighters. It was these mounting losses which forced I./NJG 2 out over the North Sea and away from mainland Britain. I would suggest that the Luftwaffe's first intruder campaign was far from 'staggering'. It was in fact defeated before it really got going.

Cheers

Steve

Where are your loss numbers coming from, they are much higher than I've seen for the Blitz in 1941.

 

[stona]

Ian White's Short History of Air Intercept Radar and the British Night-Fighter. There are varying totals published. Price gives the figures for those last three months as 27, 45, 67. The important point is that as the GCI radar controlled night fighters with their Mk III or IV AI radars came online Luftwaffe losses by night rose dramatically. We can argue about the relative merit of various sources but the trend is undeniable.
Again, in neither set of numbers are all those Luftwaffe losses due to radar equipped night fighters.

This is a dead end. The Luftwaffe never had the means to defeat or even do more than cause a minor nuisance to Bomber Command with intruder operations in 1940/41.

Later some commanders had grandiose plans, involving hundreds of intruders, for delivering hammer blows to Bomber Command by this method. It all amounted to so much hot air. Operation 'Gisela' was the closest they came. Here is not the place to discuss that operation, suffice to say that 142 Ju 88 Gs were committed. They did intercept two separate forces comprising a total of over 450 bombers and managed to shoot down 24 allied aircraft (13 Halifaxes, 9 Lancasters, 1 B-17 and 1 Mosquito) . For this meagre haul they lost, to all causes, 33 of their Ju 88s. Not quite the hammer blow the Luftwaffe was hoping for.

Cheers

Steve

 

[wiking85]

Ian White's Short History of Air Intercept Radar and the British Night-Fighter. There are varying totals published. Price gives the figures for those last three months as 27, 45, 67. The important point is that as the GCI radar controlled night fighters with their Mk III or IV AI radars came online Luftwaffe losses by night rose dramatically. We can argue about the relative merit of various sources but the trend is undeniable.
Again, in neither set of numbers are all those Luftwaffe losses due to radar equipped night fighters.

This is a dead end. The Luftwaffe never had the means to defeat or even do more than cause a minor nuisance to Bomber Command with intruder operations in 1940/41.

Later some commanders had grandiose plans, involving hundreds of intruders, for delivering hammer blows to Bomber Command by this method. It all amounted to so much hot air. Operation 'Gisela' was the closest they came. Here is not the place to discuss that operation, suffice to say that 142 Ju 88 Gs were committed. They did intercept two separate forces comprising a total of over 450 bombers and managed to shoot down 24 allied aircraft (13 Halifaxes, 9 Lancasters, 1 B-17 and 1 Mosquito) . For this meagre haul they lost, to all causes, 33 of their Ju 88s. Not quite the hammer blow the Luftwaffe was hoping for.

Cheers

Steve

So then what about my other idea of never taking the Bf110 out of production and maximizing output of those from 1941-44, so that there are well over a thousand extra for night defense during the period of 1941-44?

 

[Shortround6]

Those numbers are mentioned in the book "Nightfighters" by Bill Gunston but I have no idea where he got them from.

I would note that Gunston writes that the 96 victories in May ( and they be just claims and not confirmed losses) were in the first two weeks alone. One pilot claimed two victories in one night twice and a total of seven aerial victories, one probable and one damaged between 13 March and 9 July 1941. It took a while for things to come together (and better weather/shorter nights helped) but the Germans were not going to be able to operate over England in the summer/fall/winter of 1941 like they did in the fall/winter of 1940.

The Night Blitz also used a large number of He 111s.

There is no real reason why the JU 88 fighter could not have been built in larger numbers sooner (trading them against bombers?) but in early 1941 you are going to be dealing with early Ju 88C-2 aircraft with Jumo 211B-1 engines. Speed is given as 295mph at 18,050ft and range as 1130 miles at max continuous cruise using a forward bomb bay tank. (internal load 10 50kg bombs in rear bay?) The C-2 also had a single 20mm cannon and three 7.9mm mgs out the front. the three 20mm armament had to wait for the C-4 version. I would note that max continuous cruise is not the same as the climb rating.
A Jumo 211F was good for 1340hp/PS for take-off at 2600rpm/1.4ata (many old sources don't make the distinction between HP and PS), climb (30 minutes?) 1120HP/PS at sea level and 1060hp at 17,000ft at 2400rpm/1.25ata and a max continuous cruise of 910HP/PS at sea level and 920HP/PS at 19,500ft at 2250rpm/1.15ata.
The older Jumo 211B engine was good for max continuous cruise 800HP/PS at 14,700ft at 2100rpm/1.1ata. The Jumo 211J was good for max continuous cruise 1000HP/PS at 16,700ft.

The C-4 was based off the A-4 with the bigger wing and heavier landing gear but doesn't start to show up until the autumn of 1941 with Jumo 211F engines and the spring of 1942 sees the Jumo 211 J engines installed and the start of C-6 production.

 

[stona]

The problem was always a lack of resources. I./NJG 2 were sent off to the MTO at the end of 1941, just as many other units were withdrawn for operations in the east following the launch of Barbarossa in June (41).

Bomber Command, in fact Britain, was not a priority for the Germans. It is well known how ineffective Bomber Command operations were at this time, why would the Germans devote resources that were sorely needed elsewhere to countering it?

The war against Britain was being pursued elsewhere and by other means, not least in the Atlantic Ocean.

Cheers

Steve

 

[Erich]

well Steve you have agreed with me as to why the intruder ops stopped the movement of the only NF unit completing the task and sent to the Med. Gislea in fact was one of several intruder raids in 45 there were also at least 1-2 in 1944. gislea consumed the men flying they loitered too much over England many getting lost and ran out of fuels and crashed MIA for some, as pointed out in old materials like Parry's work and even Boitens 2nd volume getting revised as we speak. you mention lack of resources and of course this is bonafide truth nothing can get around this re for my communique' of all the ANJg's should of been involved in this type of mission, but much of what we speak is a total what-if.

 

[stona]

These were piecemeal attacks like the long pursuit operations of 1943 and the occasional intruder effort later, but rarely by more than twenty aircraft.

Schmid was quite keen on intruder operations when he replaced Kammhuber but not as a prolonged campaign. He never really got the support for his idea of mounting a few big attacks. These operations always smack of desperation to me, a bit like 'Bodenplatte' by the day fighters. 'Gisela' was intended to be such an operation, a surprise attack involving hundreds of aircraft, until Pelz got involved. There was a reason why a surprise attack was preferred and that reason was the strength of the RAF's defences.

Cheers

Steve

 

[Erich]

Gisela was known as a fact by British sources it was just the date was not known, really a bad plan many pilots had not a clue where they were going even with directional maps in the Bordfünkers hands as H. Rökker and several others that flew on this mission told me, maybe just too late in the war. Peltz and I will say it was a dumb ass

 

[stona]

Peltz and I will say it was a dumb ass

He certainly messed up 'Gisela'.

I should have said that Schmid preferred a few 'surprise' attacks rather than a long campaign because of the PERCEIVED strength of the RAF's night defences. In fact, by the period in question, these had to a large extent been wound down. The Luftwaffe's intelligence was as poor as ever.

Cheers

Steve

 

[Glider]

Which mark of the Beaufighter, the 1944 version or the 1942 one? Which version of the Hercules engine, or the early Merlin engined Beau?

I am so tempted to say the one that carried a torpedo. The TFX engine Hercules XVII which developed 1,725hp. The major version of the Hercules was the VI which developed 1,650hp As for the performance difference speed at 3,500 ft was the same with both engines but below that the XVII gave an extra 9mph
Max speed carrying the torpedo was 308mph, max climb carrying the torpedo 1,460 ft/min

 

[Koopernic]

I am so tempted to say the one that carried a torpedo. The TFX engine Hercules XVII which developed 1,725hp. The major version of the Hercules was the VI which developed 1,650hp As for the performance difference speed at 3,500 ft was the same with both engines but below that the XVII gave an extra 9mph
Max speed carrying the torpedo was 308mph, max climb carrying the torpedo 1,460 ft/min

AFAIKT the production Hercules was only ever a single stage single speed engine. The Junkers Jumo 211 had a two speed supercharger from the 1200hp Jumo 211B version onwards. The result was that the Beaufighter was a beast of low altitude where it had quite stunning performance, hardly any slower than single engine fighters up to the end of 1943 but rather unremarkable at higher altitudes. Improvements with the 1350hp Jumo 211F was a more heavily pressurised cooling circuit that prevented boil of a the low pressures of high altitude and with the 1420hp Jumo 211J came an intercooler.

The Ju 88A4 with the Jumo 211J engine with dive brakes removed, with bomb external shackles removed was 317mph. There were two rather large bomb bays adjacent to each other where the wing was, however it must have been subdivided because of the wing spar or structural reasons. The forward bomb bay could carry 18 x 50kg/110lbs bombs while the rear bay could carry 10 x 50kg/110lbs: that's 1400kg or 3100lbs, not too shabby. In this configuration range was just over 1100 miles at max cruise. Two shackles could be added under each wing a 500kg/1100lbs one and a 1000kg/2200lb unit. A 900L (200 Imp gallon) tank could be carried under each wing. The ventral bondola, apart from providing for a pair of machine guns, egress/ingress also had a window on the front for the Lotfe 7 bomb sight. If the bombsight was not required a single 20mm canon could be fitted there. In the event of emergency exit requirements or in event of an engine failure the bondola could be jettisoned.

I would suggest that the Ju 88C4/C5/C6 would have had the same speed as the Ju 88A4; 317mph. I would say 3000lbs of bombs and single bomb rack fitted to carry a single 900L drop tank would make the Ju 88A4/C4/C6 difficult to catch by the Beaufighter depending on altitude. The Hercules engine was more powerful and the beaufighter smaller but the Jumo 211 had less drag and a better/equal altitude performance.

The problem with this configuration is perhaps that 28 x 50kg bombs is a good bomb load the bombs are a little small for causing serious damage to heavy items such as machine tools, bridges it will destroy most single story buildings and factory wharehouses.

The max cruising speed of the Ju 88A1 with only 1200hp from the Jumo 211B with 4 x 250kg (1000kg or 2200lbs bombs) carried externally at maximum sustained cruise was around 385kph(238mph).
Beim-Zeugmeister: Page 6 - Ju 88 A-1, set-up state B, loading case 5

Wikipedia gives the Ju 88A4 as capable of maximum speed of 271mph with 4 x 500kg (4400lbs) carried externally, probably with dive brakes. The speed of the Ju 88 carrying bombs externally was no less than that of other contemporary aircraft with bomb bays: obviously installing a bomb bay thickens the fuselage and slows the aircraft down. Ju 88 was also one of the few aircraft able to carry two torpedos.

The flaw in the Ju 88 seems to be the subdivision of the bomb bay which because they were next to each other might have formed a rather large contagious unit, more or less the length of the wing root chord. I don't know what the designers were thinking: I would say the requirements for dive bombing forced this upon them.

 

[Greyman]

Wikipedia gives the Ju 88A4 as capable of maximum speed of 271mph with 4 x 500kg (4400lbs) carried externally, probably with dive brakes. The speed of the Ju 88 carrying bombs externally was no less than that of other contemporary aircraft with bomb bays: obviously installing a bomb bay thickens the fuselage and slows the aircraft down.

Wikipedia seems very optimistic in this case. According to what I have the Ju 88 with external bombs was about 255 mph at about 17,000 feet.

A Blenheim IV and DB7/Boston are faster - the DB7 by a huge margin.

I don't have real tests on the types but the LeO 451 and Tupolev SB certainly appear faster as well.

With 4 x 500 kg external bombs the Ju88's speed is actually more in the region of a Fairey Battle (without external), Hampden (without external) and Wellington II.

 

[wuzak]

AFAIKT the production Hercules was only ever a single stage single speed engine.

Some had 2 speed engines.

Check Table II: FTH MS 4,600ft, FS 12,100ft for climbing
and Table IV: FTH MS 8,500ft, FS 15,600ft all out level speed.

http://spitfireperformance.com/beaufighter/x7542speed.gif