Ju-88, fact or legend

[pinehilljoe]

Was the Ju-88 really a great plane? On paper the specifications fall between the B-25/26 and the A-20. I don't think it comes close to the Mosquito. Is it a legend because it was the best the Luftwaffe had?

So your opinions?

 

[davebender]

Paper specifications typically fail to mention things like bombing accuracy and crew protection. Two areas where the Ju-88 was superior to most of the competition.

 

[tomo pauk]

Allegedly Stalin wanted from Soviet constructors to came out with a bomber that wouod've been better from, specifically, the Ju-88; the Tu-2 was born from that request. If the whole story is true, the Soviets rated it very high.
How good it was? Not the best bomb truck around, not even the best Germany had, especially once Do-217 is around. Not the best night fighter, not the best recon of attack aricraft. Much or it's limitations in bomber role stem from the restricted bomb bay, while for a night fighter it was a big aircraft.
On the other hand, the basic airframe was adaptable enough to serve in many different roles with reasonable success, on engines that were many times of modest power - that should up the aggregate.

 

[Graeme]

Just curious. Found a source saying the Ju-88 was "largely" designed by two Americans who specialised in stressed skin-construction.
Is this true?

 

[tomo pauk]

Hmm - what source is that?

 

[mikewint]

The Junkers Ju 88 was one of the most versatile and effective combat aircraft of World War II. Its closest counterparts on the Allied side were the Mosquito and Beaufighter. The German aircraft was larger and slower, but nevertheless very effective. 14,676 were built, including a staggering 104 prototypes for its 60 different versions.
Design was initiated by Junkers Chief Designer Ernst Zindel. He was assisted by Wilhelm Heinrich Evers and American engineer Alfred Gassner. Evers and Gassner had worked together at Fokker Aircraft Corporation of America where Gassner had been Chief Engineer.
The general staff of the Luftwaffe made some fateful decisions. On the one hand the Ju 88 was given the highest possible priority, with increasing concern expressed as the war came nearer and production still remained behind schedule. On 15 October 1939 Dr. Heinrich Koppenberg was put in charge of it, and given the authority to requisition any production facilities he needed; but the results were still disappointing. On the other hand the Luftwaffe had requested that the Ju 88 would be converted into a dive bomber. This inevitably slowed down the development and reduced flight performance. Installing dive brakes under the wing was the smallest problem: The need to reinforce the structure for dive bombing attacks caused a considerable increase in weight. Larger internal bomb bays and external bomb racks for four 500kg bombs increased the problems, and when the first production aircraft came off the line in August 1939, a number of restrictions had to be imposed. Even after all necessary modifications had been carried out, pilots did not usually achieve dives steeper than 60 degrees, although the excellent flying characteristics and automatic dive bombing equipment of the Ju 88 did not make such attacks particularly difficult. But there was little operational need for dive-bombing, except for anti-shipping missions.
The Ju 88 was easy to fly, gentle, responsive, and maneuverable, without vices. These were the characteristics which also made it an excellent nightfighter. A point of criticism for allied test pilots was the cockpit. The extensive framing of the many panels resulted in a fairly restricted view. In the bomber versions it was also rather cramped and inefficient, although the close grouping of the crew made communication easier.
When the war broke out the Ju 88 was an excellent bomber, but only a handful were available and production was not more than one per week. Just one Gruppe was equipped with Ju 88s. In the third week of the war four Ju 88A-1s attacked British warships at Scapa Flow, but they caused no damage. A Ju 88 had the dubious honor to be the first German victim of RAF fighters, on 9 October 1939, but nevertheless the RAF recognized it as the most formidable bomber of the time. The most important bomber version was the Ju 88A-4, with longer span wings, a stronger airframe, and Jumo 211J engines. It appeared in the summer of 1940. The strong points of the Ju 88 were speed and a significant bomb load. Its weak points were its short range (this was often extended by carrying additional fuel tanks in the bomb bays), a cramped and inefficient cockpit, and poor defensive armament. During the Battle of Britain the Ju 88 proved that it was the best German bomber, but operations from bases in Norway, without fighter escort, still resulted in heavy losses. And as the fight progressed, a shortage of trained bomber crews became apparent.
The more streamlined Ju 88B series did not enter production, but was developed into the Ju 188, the successor of the Ju 88. But in 1942 a new attempt was made to increase the speed of the Ju 88. The resulting Ju 88S had a well-streamlined glass nose, and BMW 801 radial engines or Julmo 213 in-line engines with more power the Jumo 211. On most aircraft no external bomb racks were fitted, the ventral gondola was often removed, and armor was reduced. This increased speed to 612km/h, much faster than most other bombers of the war.
The Reichsluftfahrtsministerium (RLM) had granted Junkers permission to pursue, at low priority, the development of a heavy fighter-bomber version. This became the Ju 88C. The transparent bomber nose was replaced by a metal nose cap, containing at first three 7.92mm machineguns and one 20mm cannon -- a relatively modest armament, but many models could carry two more 20mm cannon in the gondola under the nose. There also were a lot of variations in defensive armament. The Jumo 211 engines were retained, because the Ju 88C had too low a priority to get the desired BMW 801 radials. The first production model, Ju 88C-2, retained bomb bays, and it operated as a long-range coastal patrol aircraft, initially flying anti-shipping strikes from bases in Norway. Soon the Ju 88C-4 appeared and its roles were extended to include night attacks on British airfields, ground attack missions, flying escort for transport aircraft, and providing air cover for convoys.

 

[DerAdlerIstGelandet]

The Ju 88 was a good performer and one of the most versatile aircraft ever built. It was not the best at anything (even though one could argue it was the best night fighter), but it was good or better at everything.

No it was not a case of the best the Luftwaffe had, it was a great aircraft.

 

[Shortround6]

It was great aircraft, but perhaps not as great as many of it's post war proponent claim. It's adaptability was perhaps also it's curse.
The Jack of all trades is seldom the master of any one trade. The JU-88s structures ability to stand up to dive bombing attacks also meant it could perform the day heavy fighter role and the night fighter role. Please remember that the Mosquito was supposed to be limited to under 6 Gs in turns or dive pull-outs and the B-25 was probably under 4 Gs.
The Germans, in general, played more games with internal fuel tanks in bomb bays and carrying external war loads than most other air forces ( or perhaps they simply listed the possibilities but didn't often use them in operations?) which leads to all kinds of belief in exaggerated capabilities by arm chair air marshals 30-75 years after the war.
The Germans did use them to great effect in a number of roles but the combinations of speed, range, and payload often listed for them in many internet sites (or books) don't stand up to examination of German manuals. That doesn't mean that the bomber versions didn't carry heavy loads for short ranges or manage to drop at least a few bombs at long ranges, or when running light have a turn of speed (or altitude) that made interception difficult (running full load may have been another story but that was true for many bombers and even a few fighters).

 

[parsifal]

Bomber version
Its strengths were its accuracy, versatility and strength. its weaknesses were poor armament, bunching of the crew together, and later, its speed compared to similar opposing types.

Fighter version
Strengths; Range, weapon configuration
Weaknesses Manouverability and speed

 

[GregP]

Max g for the B-25 at 20,000 lbs. was +3.67 g, decreasing to +2.67 at 34000 lbs.

It's hard to imaging one at 34,000 lbs. ...

At 20740 lbs, you had items including 6744 lbs. gasoline, 3500 lbs bombs, all crew and ammunition. So, you'd have to WORK at it to get a whole lot higher.

 

[tyrodtom]

Max g for the B-25 at 20,000 lbs. was +3.67 g, decreasing to +2.67 at 34000 lbs.

It's hard to imaging one at 34,000 lbs. ...

At 20740 lbs, you had items including 6744 lbs. gasoline, 3500 lbs bombs, all crew and ammunition. So, you'd have to WORK at it to get a whole lot higher.

Wait a minute Greg, you take just the 6744 lbs gas and 3500 lbs bombs away from 20740 you come up pretty close to what a empty P-47 weighed. I don't think so

 

[wuzak]

Specifications (B-25H)[edit]
Data from United States Military Aircraft since 1909[42]

General characteristics

• Crew: 6 (one pilot, one co-pilot, navigator/bombardier, turret gunner/engineer, radio operator/waist gunner, tail gunner)
• Length: 52 ft 11 in (16.13 m)
• Wingspan: 67 ft 7 in (20.60 m)
• Height: 16 ft 4 in (4.98 m)
• Wing area: 610 sq ft (56.7 m²)
• Empty weight: 19,480 lb (8,855 kg)
• Max. takeoff weight: 35,000 lb (15,910 kg)
• Powerplant: 2 × Wright R-2600-92 Twin Cyclone 14-cylinder air-cooled radial engine, 1,700 hp (1,267 kW) each

Performance

• Maximum speed: 272 mph (237 kn, 438 km/h) at 13,000 ft (3,960 m)
• Cruise speed: 230 mph (200 knots, 370 km/h)
• Range: 1,350 mi (1,174 nmi, 2,174 km)
• Service ceiling: 24,200 ft (7,378 m)

Armament

• Guns: 12–18 × .50 in (12.7 mm) machine guns and 75 mm (2.95 in) T13E1 cannon
• Hardpoints: 2,000 lb (900 kg) ventral shackles to hold one external Mark 13 torpedo[43]
• Rockets: racks for eight 5 in (127 mm) high velocity aircraft rockets (HVAR)
• Bombs: 3,000 lb (1,360 kg) bombs

North American B-25 Mitchell - Wikipedia

 

[GregP]

All you have to do to think so is read the Pilot's Operating Handbook. That comes straight out of a POH.

 

[Shortround6]

There is a manual for the B-25C & D in the manuals section, perhaps for other models?

At any rate 20,740lbs was the manual basic weight, this is empty equipped (sort of) with guns and some equipment but no fuel or oil (except residual), bombs, crew, crew equipment, parachutes, brief cases (honest that what it says for pilot and co-pilot) and special equipment. Weight break down is on page 34B.

However the 3.67 G limit extends to 26,000lbs and goes down after that 2.67 Gs from 29,302 to 34,000lbs. Max allowable indicated airspeed drops at the higher weights. G limits are on page 23.

Interesting as this is what means is that the B-25 would have made a lousy heavy day fighter (no matter how good a strafer it was ) or a lousy night fighter as the low G Loading and the low max indicated speed limit (340mph indicated) limit it's ability to turn or dive.
Yes they were used as night fighters on occasion but obviously something that could turn better and dive faster would do a better job.

Going back to the Ju-88, it didn't have to out turn single engine fighters but being able to out turn twin engine and four engine bombers allowed it into get into firing position more often and these higher limits are a result (unintended ? ) of the dive bombing requirement.

The heavy construction also allowed for the fitting of much more powerful engines later in it's career with not to much trouble.
An experimental B-25 with P & W R -2800 engines ripped it's own wings off pulling up form a low altitude speed run let alone pulling out of a dive.

 

[Greyman]

Data Sheet info for B25C:

wing unit: 2,900 lb
tail unit: 550 lb
body: 2,100 lb
nacelles: 1,000 lb
chassis: 2,000 lb
power unit: 6,410 lb
fixed equipment: 3,987 lb
empty weight: 18,947 lb

 

[GregP]

Hi Greyman,

You are correct and I mis-read the page. It's on page 34B in the attached file. I read the weight at the top and ... stopped! Just hurrying to get to other things. The real flight weight is at the bottom (34k). That's two mis-reads in one night, so I refuse to disagree with anyone else for at LEAST a week. About 10 minutes after I posted the above, I was thinking ... "Wait, we were heavier than 20,000 last time I FLEW in it!" and went back to verify.

Open mouth, insert foot.

 

[davebender]

weaknesses were bunching of the crew together
I disagree.
Bunching crew together allowed them to be protected by an armored cocoon. Common in modern combat aircraft but an advanced concept for 1938. Me-210 took the concept a step further with remote control defensive armament that could be operated from within the armor protection.

 

[tomo pauk]

But there was no armored cocoon on the Ju 88, whatever the armor was around it was strictly on individual basis, like the bullet-proof seats.

 

[fastmongrel]

Bunching the crew can also mean one 20mm HE round exploding in the cabin and no one gets out alive.

 

[mikewint]

The Ju-88 and Mosquito faced off head to head on many occasions so a fair comparison.
Comparing specifications was quite interesting.
Numbers built for the aircraft are as follows, 7,781 Mosquitos built and in operation for 16 years. 15,000 Ju88's built and in operation for 15 years. ( Operation dates as test flight to retirement ). So both aircraft operated over a similar time span with the Mossie lasting into the mid 1950's.
Overall dimensions of the aircraft were very similar, differing by just a few feet. What surprised me was that the Mosquito had the highest Gross Weight at 18,100 lbs and the Ju88 at 16,980 lbs
Payload was, Mossie 4,000 lbs and the Ju88 5,511 lbs.
Range was, Ju88 1,310 miles and Mossie 1,500 miles.
Horse power was significantly lower for the Ju88 at about 1,200HP each engine compared to the Mossie with 1,710HP.
Service ceiling was, 29,800 ft for the Ju88 while the Mosquito is listed as having a ceiling of 37,000 ft. The Mosquito wins on top speed as you would expect having an additional 1,000 HP against its competitor. Mossie was 415mph at 28,000 ft and the Ju88 was 317mph at 15,600 ft.
Crew numbers were two for the Mossie ( I presume the Bomber version used the Navigator as bomb aimer ) and the Ju88 had four.
Both the Ju88 and Mossie were very adaptable, which must be a big part in their success. I don't know if any captured Ju88's were flown in simulated combat with Mossies, but it is likely. I haven't seen any RAF figures for the Ju88 v Mossie, 'though the RAF operated captured German aircraft to assess their abilities. Someone somewhere will probably have the figures, maybe Terry?
On paper, the Mosquito does look like it comes out top in most respects, but there is much more to fighting a war than statistics. Pilot training also has a big impact on an aircraft's ability, and that is an area that let the Luftwaffe down, by their not sending experienced pilots to training schools to pass on their knowledge.