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IMHO the Ju88 was a specialist airframe and shouldn't carry anything externally except for a fighter-bomber version like the Mosquito. Otherwise a medium bomber like the He111 or Do217 should be carrying the heavy loads; if you are taking on 3000kg externally for the Ju88 then it has to be structurally strengthened even more, which adds more weight, which means less range and speed, thus compromising the design. Its not worth it, because the Ju88's main selling point is its speed; once that is compromised it loses its purpose and its job can be done better by a slower medium bomber with more armor and defensive guns and carry a heavier load further.You don't realy want to built this bomber without any ETC'S?
To my opinion such a fast bomber must also be able to carry 3000kg with the racks (ETC's), alone to have the flexibility.
I'm totally against a dive bombing version. This version is a speed bomber, recon aircraft, nightfighter/intruder, and perhaps gunship. It was too big to reliably dive, which is why it was restricted to glide bombing early on (55 degree attacks).1. Should this version be the only version till a nightfighter, or do you also want a normal Ju 88 with 55 degree dive capacity?
The He111 was mostly using the Jumo 211 as of March 1939 when the H-series (Jumo engined) was ready. The DB series, which was very small, the P-series, was ready earlier due to the better DB performance, but there were just too few engine available. IIRC by September 1939 only 400 engines a month were being produced from all factories; a year earlier it was even less. Meanwhile Jumo had triple or quadruple the number of engines.2. From where should come the engines for the Heinkel 111? At 1939/40 the He 111 was flieing DB 601.
The H variant of the He 111 series was more widely produced and saw more action during World War II than any other Heinkel variant. Owing to the uncertainty surrounding the delivery and availability of the DB 601 engines, Heinkel began tests with the 820 kW (1,100 hp) Junkers Jumo 211 powerplants. The somewhat larger size and greater weight of the Jumo 211 engines were unimportant considerations for a twin engine design, and the Jumo was used on almost all early-war bomber designs. When the Jumo was fitted to the P model it became the He 111 H.
The He 111 H-1 was fitted with a standard set of three 7.92 mm (.312 in) MG 15s and eight SC 250 250 kg (550 lb) or 32 SC 50 50 kg (110 lb) bombs. The same armament was used in the H-2 which started production in August 1939.[47] The P-series was gradually replaced on the eve of war with the new the H-2, powered by improved Jumo 211 A-3 engines of 820 kW (1,100 hp).[47] A count on 2 September 1939 revealed that the Luftwaffe had a total of 787 He 111s in service, with 705 combat ready, including 400 H-1 and H-2s that had been produced in a mere four months.[48] Production of the H-3, powered by the 895 kW (1,200 hp) Jumo 211 D-1, began in October 1939. The experiences during the Polish Campaign led to an increase in defensive armament. MG 17s were fitted whenever possible and the number of machine guns was increased to seven. Normally one MG 17 would be installed in the nose, one in the ventral position, dorsal position and one in each waist window position. The two waist positions received an additional MG 15 or 17. On some Heinkels a permanent belt-fed MG 17 was installed in the tail.[47]
After the Battle of Britain, smaller scale production of the H-4s began. The H-4 was virtually identical to the He 111 P-4 with the DB 600s swapped for the Jumo 211D-1s.[49] This variant also differed from the H-3 in that it could either carry 2,000 kg (4,410 lb) of bombs internally or mount one or two external racks to carry one 1,800 kg (3,970 lb) or two 1,000 kg (2,210 lb) bombs. As these external racks blocked the internal bomb bay doors, a combination of internal and external storage was not possible. A PVR 1006L bomb rack was fitted externally and a 835 L (221 US gal) tank added. The PVR 1006L was capable of carrying a SC 1000 1,000 kg (2,210 lb) bomb. Some H-4s had their PVC racks modified to drop torpedoes.[49] Later modifications enabled the PVC 1006 to carry a 2,500 kg (5,510 lb) "Max" bomb. But 1,000 kg (2,200 lb) "Hermann" or 1,800 kg (3,970 lb) "Satans" were used more widely.[50]
BTW as an aside I'm wondering why DB never tried to go the Jumo route and work on a smaller DB that used higher RPMs. The DB605 was bigger and though it used a similar cooling system and ran with higher RPM it was only equivalent to the Jumo 211J in terms of output. AFAIK the 605 never broke the 1500hp mark.
So perhaps instead of a DB603, which we agree is problematic, why not go for a Daimler Benz version of the Jumo 213?
That's not what the article is saying at all; it is including all other previous types of He111 prior to the H and P series as well, which were still in service. A DB600 naval series for instance was produced, not to mention the lower performing pre-DB601 and Jumo 211 engine equipped series.I have also several books and the engl. wiki articel is wrong from the timeline!
The He 111 P series was with DB 601 engines and this engine wasn't deliverable until December 1938/January 1939, that are the same month were the Me 110 and Bf 109 started with the production. And now the englisch wiki want to tell me that next to the 834 P series also 400 H series were built at 1939?
This is wrong!
Source on that? I have a book on the He111 that confirms the wikipedia article:The Jumo 211 was at the beginning exclusive for the Ju 87 and Ju 88 and not until enough were produced, it was also delvered to Heinkel. The timeline from the english wiki is wrong.
Luftwaffe Aerial Torpedo Aircraft and Operations in World War II: Harold Thiele: 9781902109428: Amazon.com: BooksI totaly disagree with your analyse about the Ju 88 as maritim strike aircraft, also the Ju 88 was equiped with torpedos. The Ju 88 was the a/c what was most dangerous at Malta beginning 1941 and at Kreta 1941 to the english navy.
The He 111 was ok but far away from the performance of the Ju 88 with it's possibility to dive.
The trick is to do more research and funding for the F5B before the war. The whole funding between 1936-1940 was 100000 RM for a Aircraft Torpedo, this was one of the biggest jokes and mistakes. Not until Tarent has shown what was possible, the funding was massively increased.
We have said this before many times but it seems to need repeating.
When you increase the rpm the stress on the crankshaft and reciprocating parts and the crankcase go up with the square of the speed. going from 2200rpm to 2700 rpm increases the stress loads by 50%. You need a stronger crank, stronger con rods, stronger pistons, a stronger crankcase to keep things from flexing and better bearings. Friction also goes up with the square of the speed so you have 50% more power lost to friction. Not a really big deal but you don't get 22.7% increase in power you think are going ot get from the RPM increase
Going from 2400rpm to 3200rpm increases these loads by 77%.
The higher the RPM the more problems you can run into with vibration, especially harmonic vibration.
Of course. There is no such thing as a free lunch.
Lot of BS in this book, should I mention MG 151 as cowl gun in the Bf 109K?William Green's Warplanes of the Third Reich mentions being able to fit 2x 250kg bombs in addition to the 50kgers.
BTW as an aside I'm wondering why DB never tried to go the Jumo route and work on a smaller DB that used higher RPMs. The DB605 was bigger and though it used a similar cooling system and ran with higher RPM it was only equivalent to the Jumo 211J in terms of output. AFAIK the 605 never broke the 1500hp mark.
So perhaps instead of a DB603, which we agree is problematic, why not go for a Daimler Benz version of the Jumo 213?
That's my point, Daimler did not produce a base 1750hp with the DB605. They could have done something like the Jumo 213 and gotten a heavier engine with higher base rpm rather than going the 603 route of high displacement. The 603 potentially offers an earlier high hp option, but so too could the DB605 if modded like the Jumo 213 by 1942, which is the predicted 'ready' date of the 603 anyway.
Fair enough. Thanks for the explanation. All I'm saying is the 213 and 211 had the same displacement, which was also the same as the 605. Theoretically it was possible to go the 213 route with a DB engine, but given the limited engineering capabilities of Daimler for aero engines compared to the Jumo it makes sense why they didn't. Having the DB603 probably would result in an earlier production engine of a high output aero engine rather than redesigning the DB601/5.The DB 605 was pretty much useless as a bomber engine (or heavy aircraft engine) once you get past the 1475-1500 Mark. Much like some of the late war Merlins while the PEAK 1-5 minute ratings went up, the climb and max cruise ratings did not.
You need the 603 or Jumo 213 for the higher climb and cruise ratings and the fact they can use the higher power levels without needed additional maintenance or affecting overhaul life, like using water injection?MW 50 or over boosting bring on.
Please note that R-R never changed the RPM of either the Merlin or Griffon, They were able to use increased boost pressure instead. An option not really open to the Germans or at least not to the extent it was to the British due to fuel.
Do not really compare simple RPM, Piston speed is the more accurate comparison of the strain on bearings and corrected piston speed is even better. Corrected Piston speed is the piston speed divided by the square root of stroke/bore ratio. Under square engines get the number reduced and over square ones get it raised to account for the bigger (heavier) pistons.
For example the Merlin is 3000fpm ( 6in stoke X 2 for every revolution) but is corrected to the sr. rt. of 6/5.4 x 3000 for 2846.
A DB 605 at 2700rpm is 2835fpm but is corrected to 2782
A DB 603 at 2700rpm is 3190fpm but is corrected to 3026
A Jumo 213 at 3250rpm is 3520fpm but is corrected to 3200.
These are theoretical numbers and in actuality would be affected by actual piston and con rod weight as opposed to a "correction" factor but help explain why certain engines were limited to certain rpms without major changes. Allison required a new crankshaft with bigger counter weights that weighed 27lbs more than the old crankshaft to go from 3000 rpm to 3200 rpm, it would fit in the old crankcases though for even more crankshaft life. Some engines did not have extra room in the crankcase.