Most innovative aircraft of WW2 ?

[swampyankee]

I'm not sure what you are trying to say. That the Bf109's straight wing had something to do with the F-86's swept one? Or that all the world's transonic aerodynamics knowledge was in Germany? If it's the latter, start by learning about the Fifth Volta Conference on high-speed flight, in 1935, and then go through the bibliographies of RT Jones, Betz, Crocco, and the catalogues at NACA, ARC, TsAGI, ONERA, etc.

Lots of planes had automatic leading edge slats. Go find a Tiger Moth to check.

 

[pbehn]

How can the Bf109 take credit for the leading edge slats? They paid Handley Page a license fee to use them until 3 Sept 1939.

 

[Shortround6]

As a further note on the innovative 109.

It first flew with a Kestrel engine on May 29th 1935.
The US Army took delivery of a Boeing P-26B on June 20th 1935 with a direct fuel injected R-1340-33 Wasp engine. They took delivery of a 2nd one the next day. Within a year they army had 25 P-26s with direct fuel injected engines.
So, no, the Germans did not pioneer direct injection engines.

P & W tried direct fuel injection on the R-1340, R-1535, R-1830, R-2800 and R-4360 engines. The R-1340 Wasp was also tested in airline operation.
P & W found no benefit over the company's standard practice of injecting fuel into the slinger ring in the supercharger.

 

[GrauGeist]

Is it me, or did somebody literally disappear from the thread?

 

[DerAdlerIstGelandet]

Just cleaning it up a bit...

 

[GrauGeist]

Wait...what?
You can delete posts now?

 

[DerAdlerIstGelandet]

Always been able to. Nothing new. We just try to avoid it if necessary. I did not remove these one though.

 

[Marcel]

They are not deleted, just made invisible.

 

[GrauGeist]

Ok, makes sense now - neat feature, the "invisibility mode"!

And it does explain why the carpeting in here is a little lumpy

 

[vikingBerserker]

Yea, I was trying to follow the thread and got somewhat lost.

 

[GrauGeist]

Yea, I was trying to follow the thread and got somewhat lost.

Towards the end, there was a person who insisted that the Bf109 was a technological marvel that introduced a long list of "firsts" and didn't react well when his dreams were crushed by the cascade of cold-hard facts.

He has since then become one of the lumps in the carpet...

 

[swampyankee]

I'm wondering if there is some amount of talking past each other going on, centered around what people define as innovation vs. good design. I don't consider the Mustang* to be innovative so much as well-designed; the XP-54/55/56 were certainly innovative, but were also unsuccessful. Leaving aside jets, the engines of which forced innovation, the constraints of aeronautics and engineering placed some serious limits on novelty.

It's also difficult to say X is innovative without knowing why, e.g., were automatic leading edge slats on the Bf109 a crutch to fix a horrid stall or a design decision to reduce landing speed? The latter
could be an innovation; the former is a band-aid.

Piston-engined fighter aircraft which had some significant innovation and saw service would, in my opinion, include:

• P-39. Mid-engine. Note I don't think this was a good idea, but the P-39 was a serviceable fighter despite -- not because -- of engine location.
• P-43. Turbocharged engine. This aircraft was the first instar of the P-47.
• Boulton-Paul Defiant. Turret. Innovative, but not well-considered.
• Do335. Tandem engines.
• P-38. Configuration. Initial models had some design issues, with the engine induction system, cockpit heating, and agility.
• SAAB J-21. Twin boom pusher. Unique.

Innovation, in and of itself, doesn't equal good performance or even good design.

 

[DerAdlerIstGelandet]

They are not deleted, just made invisible.

Well for the non moderators and admin members that is essentially a delete. Only we can see them.

 

[DerAdlerIstGelandet]

Towards the end, there was a person who insisted that the Bf109 was a technological marvel that introduced a long list of "firsts" and didn't react well when his dreams were crushed by the cascade of cold-hard facts.

He has since then become one of the lumps in the carpet...

He is still a member here...

 

[pbehn]

It is perhaps hard to be very innovative when so much is dictated by the engines performance, weight and dimensions, the Merlin was a good engine but look what it went in in 1939/40 Spitfire, Hurricane, Defiant and Battle.

 

[Shortround6]

Part of the argument was that since modern aircraft use many of the "features" that the 109 did then the 109 must have been innovative.

Which is more a bunch of coincidences that piled up over the years rather than true leading the way on part of Messerschmitt team.

Like the leading edge slats.

See: rolls-royce goshawk | napier dagger | bristol perseus | 1934 | 0631 | Flight Archive
for an article about 16 prototype machines that were displayed to the public at Hendon in June of 1934, almost 11 months before the 109 first flew.
at least 7 have leading edge slats (partial span) to help maintain aileron control near or during the stall and prevent/control spins which were a big killer in WW I and the 1920s.

The use of partial span slats was very common at this time and for a good reason. Modern jets use moveable surfaces on the leading edge of the wing. But these surfaces do not have the same purpose (spin avoidance ) and a lot more to do with lift enhancement in general. To credit the 109 and it's design team with "leading the way" seems a bit much. I don't fault Messerschmitt for using them, many design teams were feeling their way forward trying to combine good handling and low drag and other requirements. The 109 followed one path, other design teams followed other paths. At the time several of these paths could be correct as long as they produced a good product.

Landing gear attached to the fuselage as innovative.
As shown landing gear had been attached to fuselages almost since the beginning of flight. It made for a light structure. It also meant that many of those Biplanes could be towed around with the wings off. As landing speeds went up (and airfields stayed unpaved or poorly paved) and large engines/props had increased torque effects, wider landing gear became a benefit. With the coming of jets and their thinner (relatively) wings hiding the landing gear in them became more problematic. In order to use skinny tires that would fit in the wing the English Electric Lighting used tire pressures approach 300lb pr sq in and many early (and not so early jets ) were concrete runway only. That and the wing (being on/near the center of gravity) became an even more desirable place to store fuel and the landing gear took up a lot of room.
The idea of towing jets around on their landing gear with the wings removed pretty much disappeared

the adoption of multiple hard points under each wing also conflicted with the space needed for landing gear.

With jets going to mid-fuselage wings or high mount wings the length/weight of wing mounted landing gear grew. Mounting the landing gear in the bottom or bottom corners of the fuselage became a more attractive option. The designers of the 109 had their reasons for mounting the landing gear the way they did. Modern jet designers have their reasons for mounting landing gear the way they do. They are not the same set of reasons although light weight and compact are certainly considerations.

The center gun argument.
The very first fighters used single machine gun, with 80-120hp it was all they could carry without seriously degrading performance.
As engine power went up for firepower (2nd gun) could be added.
During the 20s somethings stagnated. Two machine guns was considered sufficient for several reasons. Planes didn't get that much tougher or faster.
Increases in engine power were somewhat offset by increases in weight. A 400hp Jupiter engine weighed close to 800lbs compared to the the 500lbs of a 230hp Bentley Rotary. The bigger engine required a bit more fuel and a stronger airframe. Engines and airframes got somewhat more durable but their wasn't a lot excess power for large increases in gun power (although some of the guns did increase in rates of fire.)
With the coming of the cannon, which the French pioneered, the early engines didn't really have enough power to carry two cannon. Not to mention the ammunition feeds were bulky (box magazines or drums) which would not fit well into the wings.
By the late 30s engine power had picked up enough that 2 cannon were possible (if they were light) and they got the guns to function (mostly) laying on their sides which helped hide the drums. Cycle rates were low however. In 1940-41 belt fed guns with higher cycle rates became available and a single such cannon offered a fair amount of firepower (backed up by several machine guns) but the bombers had gotten a lot tougher (bigger) and a single 20mm was no longer enough. Multiple 20mm guns (many of which could not be synchronized to fire through the propeller) became the desired armament (if not always obtained)
With a few variations four 20mm guns seemed to be nice compromise between desired destructive effect and weight of guns and ammo for the plane to carry.
These are generalizations, there are a number of exceptions.
Post WWII with even bigger bombers (B-29s and TU-4s) carrying nuclear bombs called for much more destructive armament than even the four 20mm guns and faster firing guns, bigger caliber guns (or both) became standard and the missile and rocket fad started.
ending up with things like this

1/2 the armament on a F-89H. No guns left.
Vietnam and few other conflicts showed the missile/rocket armement didn't work as advertised and many planes got a gun (or two) stuck back in as back up to the missile battery which sucked up hundreds of pounds of weight and many cubic feet of fuselage space with the electronics.

But going to guns only was no longer an option as it limited a fighter too much. Most people settled on a single fast firing gun as the back up. There wasn't weight or volume enough for more than one or two fast firing guns. which wound up back in the fuselage for number of reasons, one of which is that they don't fit in the wings very well.

even turning it on it's side won't work
Of course even in the 1950s putting a heavy gun battery in the wings was getting difficult

Modern planes are designed they way they are for reasons. Perhaps some of the reasons coincide with some of the reasons that a plane form the 30s was designed, perhaps not. claiming that a 1930s design showed the way or was "innovative" because modern aircraft have a superficial resemblance to the general layout/configuration ignores all the changes in between and why they were done.

 

[swampyankee]

Nazi Germany did have some fine engineers and pioneering aerodynamicists. It did not have all of them.

I get increasingly annoyed at people who seem to think that it had all of them, and everybody else's were, at best, third rate.

I don't think WWII Germany's aerodynamicists would be quite so disparaging, especially as many of the aircraft being designed by German engineers were designing used NACA airfoils and other information, including design rules and methods.

 

[GrauGeist]

The one truly innovative aspect of the Bf109, was not the aircraft itself, but Willy.

He was able to bring together a range of existing technologies and blend them into a compact airframe that became a top performer. This would include the concept of combining the landing gear sub-frame into the lower engine mount, which not only reduced weight, but allowed for a more dynamic wing structure.
The list goes on, but in a nutshell, it wasn't the aircraft, but the man behind it.