Estimates of a Ju88G or R with Jumo 222?

[wiking85]

Continuing my series of threads on LW performance with this engine due to my interest being resparked by discussions elsewhere, what sort of performance would a Ju88G or R with the Jumo 222 have been? I'm assuming its a 2000hp A/B series (1220kg with everything) that works and is put into production in mid-1942. I'm assuming the Ju88R or G is in service in mid-1943. If its just the R-series ready in 1943, what about a 1944 Ju88G with 222 E/F series (1365kg with everything) of 2500hp thanks to improved supercharger give 1900hp at altitude (9km)?

The classic source on dimensions/weight/performance:
Junkers Jumo 222

 

[davebender]

I doubt it. Which is why they designed Ju-288 airframe specifically for Jumo222 engine.

 

[wiking85]

I doubt it. Which is why they designed Ju-288 airframe specifically for Jumo222 engine.

I don't see why not with the Ju188 wing; it was able to take the BMW 801 and Jumo 213, while the Ju388 was able to be tested with the 222.
Version Overview: Ju 388

Ju 388 J-2 9-8222 A/B
with
Jumo 222 A/B/3

Ju 388 J-2 with
Jumo 222 E/F

Ju 388 L-2 9-8222 A/B
with
Jumo 222 A/B/3

Ju 388 L-2 with
Jumo 222 E/F

 

[davebender]

Let me phrase my reply a bit differently.

If Germany proceeds with mass production of 2,500hp Jumo 222 engine then why not produce either the Ju-288 or Do-317 airframe? You will end up with a much more capable level bomber.

 

[wiking85]

Let me phrase my reply a bit differently.

If Germany proceeds with mass production of 2,500hp Jumo 222 engine then why not produce either the Ju-288 or Do-317 airframe? You will end up with a much more capable level bomber.

I'm not saying they don't I'm saying getting the Ju88 later model airframes with the 222 engine would be the quickest route to ideal nightfighter.

 

[SpicyJuan11]

Let me phrase my reply a bit differently.

If Germany proceeds with mass production of 2,500hp Jumo 222 engine then why not produce either the Ju-288 or Do-317 airframe? You will end up with a much more capable level bomber.

They're a medium/heavy Bomber hybrid, do you think that they would have been ideal night fighters?

 

[davebender]

Now you've lost me.

Historical Ju-88G was an excellent night fighter aircraft. And it will get better still when 2,350hp Jumo213J engine enter production. Late war Germany didn't need anything better. They need more fuel for operations and pilot training. Germany also needed stronger ground forces so Venlo night fighter airfield doesn't get overrun by enemy ground forces.

 

[wiking85]

Now you've lost me.

Historical Ju-88G was an excellent night fighter aircraft. And it will get better still when 2,350hp Jumo213J engine enter production. Late war Germany didn't need anything better. They need more fuel for operations and pilot training. Germany also needed stronger ground forces so Venlo night fighter airfield doesn't get overrun by enemy ground forces.

The entire point is that assuming the 1942 production date of the Jumo 222 was met, which some recent scholars of German aviation claimed was going to happen before Milch upped the spec, then it would be available about 9 months before the Jumo 213 was, be higher powered, and offer earlier and higher performance than the Jumo 213J with the E/F series. The 213J was not ready by the end of the war, while the E/F was ready even with all the detours in 1944. My entire point is that the earlier, higher powered Jumo 222A mated to the Ju88R or G is an interesting possibility that I am curious about in terms of what its performance would be.

 

[davebender]

Interesting perhaps but I doubt it would make much difference in number of Ju-88 night fighter kills achieved.

WWII era night fighter combat had little to do with turning burning. Most kills were achieved by stalking enemy bombers and then opening fire at point blank range. Electronic warfare performance was more important then aircraft performance.

 

[wiking85]

Interesting perhaps but I doubt it would make much difference in number of Ju-88 night fighter kills achieved.

WWII era night fighter combat had little to do with turning burning. Most kills were achieved by stalking enemy bombers and then opening fire at point blank range. Electronic warfare performance was more important then aircraft performance.

In terms of Mosquito interceptions it would make a big difference; without the need for C3 fuel for the BMW engines they would also be doing pretty well and it would allow them to operate for much longer as it was more fuel efficient to rise to altitude and speed from target to target without having a major penalty from the stag antlers. Engine power was a big deal in German night fighters due to the antenna used until 1945.

 

[dedalos]

On Paper ,. we could assume that a Ju88G with Berlin radar and 2500Ps engines would exceed 700km/h. However it is unknown the behanior of the aircraft at such speeds,.The maximum permissible speed would be close. Remamber that was a late 30s design
On the other hand, climbing, single engine performance, and accelaration would be greately improved and very useful

 

[Denniss]

The Ju 88 G-7 with Jumo 213E + SN-2 morgenstern antenna covered by a plywood cone was calculated with 627 km/h in 9.1 km alt, engine with Notleistung (MW-50). Without flame dampers it was calc'd for 648 km/h.
Just to have a data point.

 

[SpicyJuan11]

This is a little OT, but after capturing the H2S, why did it take so long to develop "Berlin", could it have been in service sooner? A Jumo 222 powered Ju 88 with Berlin seems like it would've been a beast.

 

[davebender]

Intercepting high altitude, high speed pathfinder aircraft such as Mosquito is a very specialized mission. Not a typical mission for WWII era German night fighter aircraft which normally cruised within a stream of 180mph (with payload) 4 engine bombers @ 20,000 feet.

If you want a squadron of dedicated Mosquito hunter aircraft then start with a very fast twin seater such as Fw-187 or Do-335. Then practice extensively for that mission with a dedicated Himmelbett controller as you will never accomplish the interception using normal night fighter procedures. Like trying to hit a speeding bullet with another speeding bullet but without the aid of modern digital computers.

 

[wiking85]

This is a little OT, but after capturing the H2S, why did it take so long to develop "Berlin", could it have been in service sooner? A Jumo 222 powered Ju 88 with Berlin seems like it would've been a beast.

As far as I understand it it took a while to understand it and get a German version reason for production in the context of the increasingly effective bombing campaign and German need to create more of what they already had in production. Plus I'm sure general Nazi inefficiency.

Edit:
found this http://www.cdvandt.org/CAVMAG-2010-Wartime Struggle.pdf

 

[SpicyJuan11]

As far as I understand it it took a while to understand it and get a German version reason for production in the context of the increasingly effective bombing campaign and German need to create more of what they already had in production. Plus I'm sure general Nazi inefficiency.

Edit:
found this http://www.cdvandt.org/CAVMAG-2010-Wartime Struggle.pdf

What an interesting read, thanks!

 

[dedalos]

Intercepting high altitude, high speed pathfinder aircraft such as Mosquito is a very specialized mission. Not a typical mission for WWII era German night fighter aircraft which normally cruised within a stream of 180mph (with payload) 4 engine bombers @ 20,000 feet.

If you want a squadron of dedicated Mosquito hunter aircraft then start with a very fast twin seater such as Fw-187 or Do-335. Then practice extensively for that mission with a dedicated Himmelbett controller as you will never accomplish the interception using normal night fighter procedures. Like trying to hit a speeding bullet with another speeding bullet but without the aid of modern digital computers.

i feel that some staffeln of Special prepared G-6s could do the job
Use the morgensten Antenna
Use C3 fuel for the Jumos 213
Further clean the airframe: Remove the defentive Mg131, the vertical cannons, restrict the forward cannons to 2x mg151s, remove some armor, Polish the aircafts surfaces,maybe fly the missions with just 2 crew members
I believe the above would be enough to catch the mosquitos. If not, the use of GM1, would certainly solve the problem

 

[Koopernic]

This is a little OT, but after capturing the H2S, why did it take so long to develop "Berlin", could it have been in service sooner? A Jumo 222 powered Ju 88 with Berlin seems like it would've been a beast.

In 1942 the German microwave program was almost completely cancelled, not from lack of progress incidentally. Hence when the H2S was recovered a lot of manpower was missing, many of the technicians and engineers latterly were drafted into the Army according to Peter Schwann who was one. It took them months to get them back.

The H2S Workings were immediately recognised, even the multi cavity magnetron with circular cavities and narrow slits which the Germans had as a low power device but not recognised.

They reproduced a device within a few weeks, substituting their own tubes which the called Berlin because of where it was first run.

Although a major program was started to reproduce it and was done so in a few weeks it's ability to detect aircraft wasn't recognised as the experimental circuit they had set up n a Wurzburg didn't have the antenna impedance correctly matched to the transmitter, when a technician recognised the problem the range went up from 13 to more like 40km. Another shock as the false myth that aircraft didn't reflect microwaves well enough for microwaves to be used had taken hold in many lower German engineering circles, it was rejected by the senior men but it did cause some damage because it's partially true. Magnetrons compensate with high powers.

Remember the RAF was using only magnetrons for ground mapping, it had not deployed magnetron equipped mosquito or beaufighters.

The German microwave program targeted 25cm and 5cm instead of 9cm. The German program wanted devices they could frequency tune and control the phase of and this ambition slowed them down and ironically slowed progress in allied technologies such as wave guides.

The 25cm devices actually succeeded at both telefunken and Lorentz. Lorentz gave up when it thought it wouldn't get an order even though it's flak radar was 80% ready for production and telefunken abandoned it to concentrate on existing radars and bizzardly lost many of its technicians to the draft.

The German navy objected as it needed a small FLAK radar and so development continued of FuMO 231 Euklid using German navy signals branch resources at a slow rate. A few of these FLAK radars with 1.5m dishes may have been fitted o a destroyer since 6 were shipped from the factory.

When the British magnetron was discovered they tried it in EUKLID and found it was worse since special signals conditioning were needed to remove the effect of sea wave interference and multipath interference, which the magnetron couldn't do. However a latter switch from the 9cm to the 3cm worked and so after an initial run they were going to switch over to 3cm EUKLID Z. Had they have persisted with their 25cm radars it's unlikely allied jamming would have succeeded.

The 5cm program produced a tunable tube that was unable around 3cm to 5cm at 600W maybe 1KW. It might have made a USEFULL radar with a range of 3km or so but it was well down on early allied radar tubes of 16kw.

By the time the new radars were close to production allied bombing disrupted it.

The Luftwaffe did have jam free SN2 and Neptune radar in 1943 and 44 for considerable periods.

One delay was caused by the bombing of tube manufacturers sanitas, the other by the bombing of the company the made the permanent magnets, necessitating a development of weaker electromagnets and their unwelcome power supplies.

The Japanese actually developed British style multi cavity magnetrons before the British but the Japanese navy never shared with the Germans, in fact they didn't seem to share with their army.

 

[Koopernic]

I doubt it. Which is why they designed Ju-288 airframe specifically for Jumo222 engine.

I happen to agree with your general assessment that one of the biggest failings was for the Luftwaffe / RLM to not develop the Big DB603 engine as fast as reasonably possible between 1937 and 1940. Instead, at the time, the Luftwaffe has bet almost everything on the Jumo 222 and the paired DB606 and 610 for its future. In a way the promise of these mega engines excused the search for aerodynamic optimisations and the use of armament removal.

Since the Jumo 222 was flight testing Ju 288A prototypes at 2000hp in December 1941 it would be reasonable to assume that it could be in production, as a reliable engine, 1 year later in December 1942 also at 2000hp.

The problem is that specification growth had increased manning of the Ju 288 from 3 to 4, the cabin became wider, armament was added, wingspan increase and thus overall weight went up several tons. Now the engine needed to be 2500hp, from the start to obtain adequate performance while altitude requirements made the addition of an inter cooled two stage supercharger important adding further development issues on top of the extra power, hence the Jumo 222 engined Ju 288b was abandoned for the Ju 288c with the infamous coupled engines, the DB610 apparently performed well in the Ju 288c prototype.

The whole program came to nought. The only way to rescue it would be to stick to the original 3 man Ju 288A requiring only 2000hp and the wait for the engine to grow either 2500hp from the Jumo 222a/b and e/f ;or 3000hp from the bored out Jumo 222c/d.

This sounds complicated and risky. If we abandon the Ju 288 and apply the engine to the
Ju 88/188/388 we might get a great improvement with only 2000hp and this might be possible from December 1942. We still don't have a proper Bombay in the Ju 188/388 as the wing spar is in the way but the additional power allows the option of a ventral bomb pack.

If we apply the engine to the Dornier Do 217M we have a proper bomb bay. Variants of the M had extended wing span to handle the high altitude launch of the Fritz-X and a speed survey greater than the 347mph the Do 217M achieved on 1750hp DB603A, this might be possible in December 1942 on 2000hp.

With incremental power growth from there:say 2200 then 2500. Production of the Do 217 came to a halt in March 1944 even as he 177 production grew.

Another scenario, the best one in my view, is that the DB603 is a fully resourced program rather than a
R&D program in the hiatus years of 1937-40. This surely must bring forward the DB603 to deployment dates
Seen with the DB605 March 1942. If the resources come from killing of the DB605 it means the Me 110F and me 109F must soldier on with the DB601E, possibly a more reliable and powerful engine than the DB605A except at altitude due to its ability to run at 1.42ata.mmimprovemnts in super chargers, boost ratings
Might even have left the DB601 ahead of the Db605A curve.

This then allows time to commission a new fighter to replace the Me 109.

Meanwhile the 1750hp Db603 grows in power and keeps the Ju 88 and Do 217 and perhaps even Me 410
Flying faster and higher than before.

 

[davebender]

That would be crazy since DB601 / DB603 / DB605 shared development technology. Better to keep all three and kill the entirely new 24 cylinder DB604 engine.

Personally I would go so far as to kill Jumo 222 and begin development of Jumo 213 engine during 1937. However if Germany is determined to have a 24 cylinder engine program then the Junkers program is the only one I would fund.