"Zerstörer" specification, but as an 1-engined fighter

[tomo pauk]

Let's say that RLM/LW by some time of 1935 is open to the attempt to fulfill the requirements for the 'destroyer' aircraft (that, by that time, do not include the gun turrets and bomb load) by an 1-engined aircraft. Requirements still include the long range ( so it can serve in it's primary task, that of bringing the fight to the enemy fighters above the enemy territory), crew of 2, as well as suitable guns' armament.
Companies mostly respond, by 1936, with a fighter powered by the DB 600C engine with the 'beard' radiator, A/C being kinda-sorta 'big fat Bf 109', or something that is sized between the future British fighters (Hurricane and Spitfire). Wing profile of the winning design - let's call it the Bf 113 - is 2R1 16 at root (vs. the Bf 109's 2R1 14.2 and 110's 2R1 18.5). Fighter is of modern looks, with cantilever wing, retractable U/C, while the radioman can also operate the defensive MG, fuel carried is 650L in the internal tanks. At 1st, the firepower is 4 LMGs and two MG FF cannons. By late 1938, DB 601A is the engine installed.

Thus the questions:
- how much this scenario is worse for the LW than the Bf 110 historical scenario from 1939-1942?
- where is this 113 scenario better than the 110 scenario, apart from the obvious (= almost a double number of aircraft is possible for the same resources spent)?
- plausible future upgrades, improvements, new tasks?

 

[tomo pauk]

Benefits of this scenario:
- less fuel usage per aircraft and per unit, both during training as well as during the opeartions
- no need for pilots to be trained for 2-engined A/C
- easy conversion into 2-seater trainer
- aircraft is a good deal smaller than the Bf 110, so it will be harder to spot, identify and hit, both for the enemy pilots and AA gunners
- less blind spots
- should roll better, being without the powerplants away from the centreline and the smaller wing
- thinner wing and no engines close to the fuselage should allow for the better dive speeds and behavior

Shortcoming:
- engine-out situation above enemy territory is a certain loss of both A/C and crew; even above the big body of water the chances for he crew to make it home is not favorable
- probably harder to make it a 3-seater (3rd crew member is handy for night fighter job, even if 2 can do the job)
- ability to carry a really hefty bomb - above 1000 kg - will be tricky until well into war; but then again, this ain't a bomber anyway

 

[MIflyer]

'big fat Bf 109', or something that is sized between the future British fighters (Hurricane and Spitfire).

I think you have just described a Defiant with forward firing guns. Now, how would that have worked?

 

[tomo pauk]

I think you have just described a Defiant with forward firing guns. Now, how would that have worked?

Also without the turret to add to the drag and weight balance sheet. Also with the less draggy radiators, less draggy exhausts and without negative G problems.
We'd probably have a 330-ish mph fighter with the DB 601A, and in numbers greater than what the LW had with the Bf 110 force by a few hundreds in 1939-40, meaning that LW can put in the air more of the long-range fighters than it was historically the case.

 

[Zmauky]

A little bigger than the 109 two-seater. How much weight are we adding? Armament is more for 2x7.9 fixed and 1x7.9 for the gunner/radio and let's say 150 kg for that second crew member (his weight, chair, equipment, oxygen, etc.)? how much fuel .. say 300l or more? What kind of long distance radio ... 50-70 kg more?
Let's say we loaded approx. 500-600 kg more with our gross 109. Visually, cut behind the firewall, moved nose (engine) forward 50 cm, extended middle 100 cm and lower the back of the tail (of course it must be double like it was in me 110 ). Wings in size between one and the other?
Of course, Willi is on all early constructions (109,110,210,410...) put the coolers on the wing, so I don't see that it would be different, but ... where is room for additional fuel - if it does go in the wing's roots, then the wheels and radiators have to be moved to the outside, so there is a problem for the MG FF (witch can't go to fuselage) , besides the biggest problem is the MG FF (drums with 60 grenades that that second guy replaced in 110 or Fw 189). So that is our biggest problem...

Ok then let's move on from weapons... Lets DB make room for gun to fire through the propeller on the 601 (and that oil reservoir can be somewhere else), find some stronger 23-25-30 mm gun and say that 1x25 mm + 4x7.9 enough. Those 4x7.9 can probably be situated (along with the radiator, wheels and tank) at the wing because we need room for that big gun a to be little more aerodynamic, but I would also move the oil cooler at the wing to reduce the cross-section of the fuselage.

An alternative solution would be a cooler on the chin, visually extended towards the rear (as on the D3A) and there were be room to accommodate the fuel (or bomb bay ).
And the performance ... 109 with 500 kg and two 300 l tanks (it flew in that configuration only as the FiSk 199 ) and even then there was a little bit of power in the game.
What would it actually serve? Like fighter I don't think so, but as light fighter bomber maybe.

As a wiff idea and for drawing / making a model it sounds great, but I think that the RL performance would be too bad to be of real combat value.


But...
(admittedly, this belongs to a slightly earlier thread)
there is a blueprint 109 (and it was probably also a model) on which they tried the wing configuration for the Bf 110.
And here's the idea.... in the story


And so DB saw that there would be money and invested its own capital in a new factory, and DB 600s started to come out like clockwork... And the Me 109D got those great new engines as planned. And it put the Junkers concern in a problem (what about those extra 800 Jumo 210). And then some petty engineer from Junkers came up with the idea ... look, the Fw 189 is faster than the Me 109 on our engine, let alone the Me 110, let's sell Willy that he is a worse designer than Kurt ... and that's how the Me 109.5 was born. The first use showed that...


So our Me 109.5 looks like this - we cut off the Me 109 on the firewall, push the pilot forward, 4x7.9 go into the tip of the nose, place 2xMG FF so that the pilot can possibly change those problematic drums (or use something better with more ammo), behind the pilot and in the center of gravity there is now room for 4 times larger tank. We also have to enlarge / make the tail heavier, so let's say we use something like the 209/309 tail and extend the fuselage a little more (like the Fw 190D). Wings - the outer part are the same bf 109 wings, but without wheels, radiators and weapons, then nacelles with Jumo 210, chin radiator and landing gear, and a straight wing extension of the same section from the nacelle to the wing root, say 1,5 m length. The performance (except the range) cannot possibly be better than the me 109G (quantity of ) but if it is 1940 ..

 

[Shortround6]

Thus the questions:
- how much this scenario is worse for the LW than the Bf 110 historical scenario from 1939-1942?
- where is this 113 scenario better than the 110 scenario, apart from the obvious (= almost a double number of aircraft is possible for the same resources spent)?
- plausible future upgrades, improvements, new tasks?

It won't be able to tangle with single engine fighters any better than the Bf 110 did and it may do worse.
Streamlining only goes so far and with a worse power to weight ratio meaning lower ceiling and poorer climb (and bleeding off speed in turns faster) fighter to fighter is not looking good.
The Defiant got to 723 Liters (?) in a 250 sqft wing but only in the MK II with the Merlin XX engine. And the only thing the Defiant wing had to hold was the landing gear.
There was a reason the Bf 110 used an 1.5 wing in the root section. It makes it easy to fit the fuel tanks in

Now maybe you can make 75 or 90 round drums for the cannon in 1938-39-40 but trying for 120-180 rounds is a bit of stretch.
Cutting the ammo load for the 7.9mm guns may pay dividends. 1000rpg was rather ridiculous for the 110. (and for just about everybody else that stuffed 1000rpg of small caliber ammo in a fighter, Looking at the groundhog here).

You do have a lot less room for growth/upgrades. While the 110C-4 got a pair of racks for 250kg bombs it needed 601N engines to do it and while upgraded landing gear allowed for heavier loads on later versions a single DB 601 powered plane was going to have trouble lifting a 500kg bomb or many of the combinations that the 110D/E/F did.

Needing 100 planes to carry 100 500kg bombs instead of 50 twin engine planes is not a big bargain. And the later twins could often carry a pair of 250kg bombs and pair of drop tanks.

 

[Zmauky]

Yes, I agree with the conclusions with one exception, the Ju 87B did flew to London with a 1000 kg bomb at approximately that power (albeit without a gunner, at night and at a speed that we will not mention)

 

[Zmauky]

Actually ... the ideal plane that would meet the requirement, if we don't count the second crew member existed and flew with 2x20 mm + 2x12.7 and DB 601 (kind off) and that is .... Ki-61.

When we compare the Bf 109E and the other fighter planes that flew on the DB 601, it turns out that the Bf 109 should be changed. And I don't accept that these are newer designs - the Spitfire is how much older ? And even the He 112 (with fat Hawker wings) had better aerodynamics = faster on same engine.

 

[Shortround6]

Yes, I agree with the conclusions with one exception, the Ju 87B did flew to London with a 1000 kg bomb at approximately that power (albeit without a gunner, at night and at a speed that we will not mention)

and used a 343 sq ft wing to do it. If you are going to use a wing 83% as large as a 110 you might as well just build the twin

Actually ... the ideal plane that would meet the requirement, if we don't count the second crew member existed and flew with 2x20 mm + 2x12.7 and DB 601 (kind off) and that is .... Ki-61.

And that doesn't show up until fall of 1942 and that is a version with two 7.7 and two 12.7mm guns. The 20mm guns show up later. Radio is rather questionable.

 

[Zmauky]

Ok - it was more or less a friendly provocation, but the fact is that it is possible to lift 1000 kg with the power of the Jumo 211 (or a modified cannon shell of approx. 800 kg with 1000 hp and 37.7 m2 from the carrier), that of course it is not a destroyer .

Admittedly, Messerschmitt (or the Luftwaffe) tried, historically, twice with half that, i.e. 500 kg. First with one of the Me 155 variants and later with the aforementioned FiSk 109.


And yes, the Ki-61 and Mc 202 and Re 2001 and Ki-60 and He 100 are later designs, but my point was that the blocky, with lots of different openings, radiators, things sticking out, various protrusions, the design of the Me 109E was quite non aerodynamic (not to say bad). In fact, we can almost take the Me 109F and squeeze in a few hundred extra liters more and even if we reduce its power by a few hundred horse difference (to get to the level of DB in the Me 109E) it would still be competitive for Tom's proposal.

And yes, as I wrote, if the He 112B was faster than the 109B (ok with 40 horses less) by 20 km/h (and with that thick airfoil), then some aerodynamically refined variant (like the 109F was) would - could handle another crew member and more fuel.

And I'm not sure that the benefit of the ki-61 was that it was a later construction than Kawasaki realized on the Ki-60 where they were wrong (mainly the radiators).
So maybe Me 109E was enough for 1939-1940 but it was not a uncatchable world winner as it would be without drastic changes (like new wing/stronger engine) but only better aerodynamic (like clean lines, no protrusion, full closed wheels, 2 instead 3 radiators ect) And looking at Spitfire or He 112 (or even Renard) it was not nuclear physic (term I use because I in it can't grab one solid facts) .

 

[z42]

Seems to me the big problem is having a sufficiently powerful engine. P-51 (and late war P-47 variants) managed to combine long range with good or even excellent fighter performance, but they had ~twice the engine power of the pre war DB 600, and weren't carrying around a backseater either. And the 51 had aerodynamics far ahead of any pre war design. Sure, you don't need to zip along at 700km/h to be competitive in 1939, but still.

My idea would be something like

• DB cancels all aero engine projects except 601/605/603, in particular doesn't put 603 on hold for several years. Thus an early 603 is available for our plane. Say, 1300 PS for the initial production version?
• Engine mounted as a 'kraftei/power egg' with an annular radiator for easy servicing and commonality with multi engine planes.
• Optional twin seat configuration. For the long range day fighter configuration an extra fuel tank is installed in place of the back seat. For the night fighter version, the backseater is an observer/navigator (later radar operator once airborne radars are a thing). No backwards firing guns.
• One MG FF as motor cannon, two MG FF's in the wings outside of the prop arc (wing roots are full of landing gears and fuel tanks) . No 7.9mm Mg's.

 

[Zmauky]

The idea with a larger / stronger engine class is interesting and would certainly enable two-seaters (fighters) to be competitive in performance with single-seaters. Defiant with Vulture for example, or Tom's single engine destroyer.
The problem is that the most powerful engines (no matter how big and heavy they were) usually went to the tip of the blade - single-seat fighters with the highest characteristics. So (at least for the RAF) the choice (if the Vulture was a successful engine) would be to put it in the super Defiant or in the Tornado - which was being developed as a replacement for the Hurricane. For doctrinal reasons the RAF would probably follow history with the Merlin engine so both in production.
I somehow think that the functional DB 603 of the late 1930s would have been intended for the next (larger) generation of German single-seaters (for example, for the Fw 190).
Admittedly, this also enables the smaller two-seater construction to be at the level of performance, but it's just a matter of benefit or purpose. With the Defiant it was armament (turret) and with us it would be .... ?