Heavy fighter: you are in charge

[davparlr]

This is a myth! After Mr. Hermann there is no single document available to prove this myth/theorie.
After his reasearch the RLM come to the conclusion that the FW 187 nightfighter was coming to late or at the same timeline with the He 219 in production and the RLM don't want to produce two new nightfighters, so the RLM decided pro He 219!
That are the reasons from the documents.

Actually I am not sure it is a myth. The fuselage is very small on the Fw-187, not much bigger than a man sitting with his legs straight out. I will try to do some measuring. I think I will find that the Bf-110 fuselage is much larger than the Fw. From the attached picture my question is, Where do you stick the radar, second crewman, two 20mm cannon and four machine guns and their ammo? Major modifications required! At the very least it would be marginal in growth. Just compare this to the He-219.

 

[davebender]

The same place they were historically located on the Fw-187A.

Personally I don't think the Fw-187 had enough interior space for a really good night fighter. However it would certainly be superior to single seat night fighters employed by Germany and the USA.

 

[DonL]

Actually I am not sure it is a myth. The fuselage is very small on the Fw-187, not much bigger than a man sitting with his legs straight out. I will try to do some measuring. I think I will find that the Bf-110 fuselage is much larger than the Fw. From the attached picture my question is, Where do you stick the radar, second crewman, two 20mm cannon and four machine guns and their ammo? Major modifications required! At the very least it would be marginal in growth. Just compare this to the He-219.

First, only the FW 187 V1 and V2 were single seater, all other 7 aircrafts were twin seater also the three A0 preproduction serie!

According to Mr. Hermann FW was always very accurate with all their project plans and calculations that were send to the RLM.

FW was the company who didn't make promises that they can't hold and didn't do high gloss marketing with special prototypes or spackled prototypes!
All their calculation to the many aircrafts that goes in production were very accurate and the promised performances from their calculation were always reached from the production aircrafts.

So FW engineers believed they can built and develope a FW 187 two seater destroyer and nightfighter with the given datas, so I have no doubt that they can do this!

 

[Shortround6]

The ammo for the 7.9mm MGs was behind the pilot. The 20mm guns were drum fed and under the floor or In the bottom 'corners' of the fuselage. I don't know if the rear seater had spare drums to reload the guns with as was done on the Bf110. As far as cockpit size goes the Fw 187 had 4-5 engine instruments mounted on each cowling above the exhaust because there wasn't room in the cockpit.
A big problem in trying to evaluate the Fw 187 is that the examples that did exist either used lower powered engines than intended or a rather experimental cooling setup. Trying to project performance forward to even bigger, heavier engines than were intended gets very complicated. The prototypes may have been overbuilt for their 740hp engines and needed no structural weight increase to use 100-1100hp engines. I am not sure the same could be said for going to the DB605. You not only have the weight if the engines but the bigger propellers, radiators, oil systems, etc. Increasing the gross weight of the plane buy several thousand pounds is going to compromise it's "G" rating with some structural beefing up. I am sure the Fw engineers could do the job. I also wonder if they really intended to use the exact same cockpit area on a proposed night fighter? There was no production tooling to "save". Adding 10CM in width or Height or both would not have been hard or extending the nose a bit. It was done on other planes and certainly was an option at the design stage. It does add a complication to simple performance estimates though.
We are left with the FW estimates which are probably better than anyone on this forum could do ( with perhaps a few exceptions,I am not one of them) but they are still estimates.
I do have the book quoted and while very interested a few details need a bit more clarification. Some ammunition load outs specified for some "paper" versions seem to be on the very generous side.

 

[DonL]

Some explanations:

To my opinion it makes only sense to bring the FW 187 in production at 1939 till end of 1940!
After this timeline I have my doubt's about the sense, because of the difficults of productline changes and the needed numbers of the war.

If you start after BoB (end of 1940), frontline aircrafts will reache the units perhaps at the begin of 1942.
At 1939/1940 the FW 187 could only go to production if the RLM cancle the Bf 110 and the Bf 210 project, to first have the resources and second the FW 187 would also been built under license from other aircraft companys like the Bf 110, because FW was limited with their capacity through the FW 190.

If the FW 187 is in production instead of the Bf 110, the FW 187 must be also play the part of the nightfighter role as the Bf 110 and the FW engineers must do their job, to make an adequate nightfighter of the FW 187 (thickened up the fuselage, extending the nose etc..).As also the Bf 110 the FW 187 can only be an interim nightfighter, because as history shown something like the Ju88 G6 or He 219 was in need to do the job properly!

In comparison to the the Bf 110 and the Bf 210/410 the FW 187 had the big advantage (if she is introduced in production at 1939/1940) that she can play more roles as the Messerschmitt aircrafts especially in the fighter/heavy fighter/long range fighter and reconnaissance role, but the FW 187 is also be able to do the destroyer role/light bomber and interim nightfighter role.
To my opinion the FW 187 had more options then the Messerschmitt destroyers and was the better multirole plane through her much better speed and agility but also with a possible payload of 8200kg.

But at 1942 a decision to produce a FW 187 with a frontline aircraft at the end of 1943 or begin 1944 doesn't make sense.

 

[davebender]

If the FW 187 is in production instead of the Bf 110, the FW 187 must be also play the part of the nightfighter role

Why not produce both?

The Me-110 wasn't just assigned to day fighter units. It was performing photo recon missions from the beginning and was performing night fighter missions by the spring of 1940. The Me-110 could still be produced in numbers adequate to equip those units. It would still be the starting point for the Me-210C light bomber.

Fw-187s would be produced in numbers adequate to equip long range day fighter units. These are units assigned to bomber escort missions.

Fw-187 day fighters would have priority for DB601 engines. Some or all of the Me-110 night fighters might be powered by Jumo 211 engines unless RLM makes different engine production decisions during 1935 to 1940.

 

[jim]

Mr DonL
Do you believe a single seat Db 605 Fw187 could make a deference in November43 -june 44 period over Germany ?
Assuming 6350 kgr loaded weight ,1475 ps output , 30 m2 wing area . These means 211 kgr/m2 wing loading, 2,15 kgr/ ps power loading at 0m (impressive) but reducing to about 2,8 kgr/ps around 7000m
P51D 192 kgr/m2 2,31 kgr/ps (assuming 1800ps merlin)
Spit IX 177 kgr/m2 2,22kgr/ps (assuming 1800ps/0m 1580 ps/7000m merlin )
P47 284 kgr/m2 ~ 3kgr/ps but up to 10000m
Could Fw mix it with these fighters over 6000m ? Surely, even with 700km/h at 7100m, and long range would be better than 190s and G6s but would be able to fight the escort fighters on equal terms? Do you have any info about its roll rate?
in Mediterennean theater 41-43 with Db 601E would be invaluable. Also on the eastern front would be excellent as multi purpose fighter bomber

 

[wuzak]

Jim, what weights are you basing the P-51 and Spitfire weight to power ratios?

 

[DonL]

Hello Jim,

Do you believe a single seat Db 605 Fw187 could make a deference in November43 -june 44 period over Germany ?
Assuming 6350 kgr loaded weight ,1475 ps output , 30 m2 wing area . These means 211 kgr/m2 wing loading, 2,15 kgr/ ps power loading at 0m (impressive) but reducing to about 2,8 kgr/ps around 7000m

Could Fw mix it with these fighters over 6000m ? Surely, even with 700km/h at 7100m, and long range would be better than 190s and G6s but would be able to fight the escort fighters on equal terms? Do you have any info about its roll rate?

This is highly speculativ, but if the estimated and calculated performance from FW would be reached from normal production aircrafts, then yes to my very personal opinion it would be a huge difference in November43 -june 44 period over Germany!

The Bf 109 G6 wasn't a success and to my opinion a step back to the Bf 109F4. Especially the G6 version of defending of the reich with the 2 gondola (151/20) was crap. Both G6 version (normal/gondula) laged speed against their enemy counterparts.
Both G6 version were in the defensive from the beginning against mostly the P 47 C/D and the P 51B. The G6 gondula even against the P38H.

The calculated single seat Db 605 Fw187 would had be major advantages!
A estimated speed of 700-725km/h at 1943, 4 x 151/20 cannons and much more range to be in the air and built a focal point with other aircrafts to attack with air supermarcy.
The speed and power to weight advantage against the P 47 C/D, P51B and the P38H would be significant at late 1943 till summer 1944.
To my opinion the calculated single seat Db 605 Fw187 is in the same performance and high altitude leage as the FW 190 D-9 but at summer 1943 and not in summer/autum 1944.

With better pilot schools and training and the tandem FW 190A/ Sturmgruppen FW 190A against the bomber and the calculated single seat Db 605 Fw187 against the escort fighter, to my opinion the defending of the reich would be much more effectiv and yes the FW 187 could fight and match the escort fighters on equal terms above 6000m.

According to Mr. Hermann the FW 187 V4 which was in Rechlin to fly against the Bf 109, rolled better then the Bf 109, but every FW fighter had a very good roll rate, this was the compensation of the poor turning performance.

To close this summary I want to say it with Mr. Hermanns Book title (FW 187: An Illustrated History) in the german version.
The FW 187: The forgotten high performance fighter!

To my opinion this statement hit the nail!

 

[Dcazz7606]

I wonder how a Tigercat with a pair of wasp Majors would stack up?

Starting design:
Single seat. Radials, say the R-2600 of 1,600 HP, close set on the wings but with sufficient prop clearance for the nose and armament to stick out. Along the lines of the Beaufighter and Tigercat, but with a thinner airfoil and more streamlined. I think a twin tail and rudder for better control in an engine-out situation. Heavy armament, probably four 20 mm cannons and maybe a single 37 mm cannon, all in the fuselage. Ability to carry some bombs, but with removable shackles.

Growth version:
Same basic layout but with R-2800 engines and four 30 mm cannons only, probably a 15% bigger wing and tail.

Should be in the high 380 – 390 mph class to start with and grow into the 400 - 425 mph class or maybe slightly faster. Probably along the the performance of the P-38 Lightning and Grumman Tigercat. I think hydraulic ailerons would have been a good thing.

Or simply take the Grumman F7F Tigercat and use that design, perhaps with twin tails, but maybe not. Maybe a competitive flyoff for the tail design.

For a single-seater, I'd opt for the Grumman F8F Bearcat. Personal preference and holder of the curent world piston speed record at 528+ mph. Later this year, Rare Bear will probably set a faster record. At least there are planes to do so.

 

[jim]

Jim, what weights are you basing the P-51 and Spitfire weight to power ratios?

Mr Wuzak
I used my limited bibliography on alleid aircrafts.
P51 Max around 5000kgr ,normaly loaded 4310 . I assumed that by the time they would enter combat the weight would have been reduced. So i choose to use 4150kgr,
Spit IX Max 4310kgr for the same reason i used 4000kgr as more representive of combat condition
In both cases used 1800ps merlins, which i believe is somewhat generous for late 43 early 44 but i wanted to balance a possible generocity in FW s performance estimations about 187.
Mr DonL
Given the great power to weight ratio and speed reserves of 187 ,and the coming of ASM engine, i would like more wing area. e.g 33m2 would bring wing loading well under 200kgr/m2 , to P51 levels, allowing perhaps turning with most single seaters and improve altitude handling .Whats your opinion?

 

[wuzak]

Mr Wuzak
I used my limited bibliography on alleid aircrafts.
P51 Max around 5000kgr ,normaly loaded 4310 . I assumed that by the time they would enter combat the weight would have been reduced. So i choose to use 4150kgr,
Spit IX Max 4310kgr for the same reason i used 4000kgr as more representive of combat condition
In both cases used 1800ps merlins, which i believe is somewhat generous for late 43 early 44 but i wanted to balance a possible generocity in FW s performance estimations about 187.
Mr DonL
Given the great power to weight ratio and speed reserves of 187 ,and the coming of ASM engine, i would like more wing area. e.g 33m2 would bring wing loading well under 200kgr/m2 , to P51 levels, allowing perhaps turning with most single seaters and improve altitude handling .Whats your opinion?

Jim, Spitfire MkIX loaded weight 7400lb/3354kg, 1720hp @ 11,000ft (Merlin 66, LF IX), MkXIV loaded weight 8574lb/3889kg, 2050hp @ 9800ft.

Source: Supermarine Spitfire variants: specifications, performance and armament - Wikipedia, the free encyclopedia

 

[DonL]

In both cases used 1800ps merlins, which i believe is somewhat generous for late 43 early 44 but i wanted to balance a possible generocity in FW s performance estimations about 187.

I'm not convinced about 1800 PS Merlins at frontline quadrons at late 1943 or early/summer 1944 wether for the Spit nor for the Mustang!

The FW 187 would also benefit from DB 605AS,ASM MW 50 and later the DB 605D serie.
I think the FW 187 would be an energy fighter and would be flown nearly as a FW 190 D-9; Bf 109 or P38.
With the introduction of the Ta 152 H1 and C serie it would be get slowly obsolet.

i would like more wing area. e.g 33m2 would bring wing loading well under 200kgr/m2 , to P51 levels, allowing perhaps turning with most single seaters and improve altitude handling .Whats your opinion?

I don't know, possible but I'm no engineer, so I can't say much to this.

 

[wuzak]

Merlin 70, PN100/130 fuel, +18psi boost 1700hp @ 10,250ft, 1475hp, +18psi boost @ 22,500ft.

PN100/150 fuel allowed +25psi sometime during 1944, 1940hp @ 5500ft.

 

[wuzak]

Form Kurfurst's site it appears the DB605ASM allowed 1800PS at takeoff, 1500PS at 6400m (20,997ft). Kurfürst - DB 601, 603, 605 datasheets - DB 605 ASM

DB605DB 1850PS at takeoff, 1600PS at 6000m (19,685ft). Kurfürst - DB 601, 603, 605 datasheets - DB 605 DB/DC

 

[Timppa]

My choice for twin would be the layout of the Do-335 because of:
1. Least drag.
2. Least rolling inertia.
3. Engine failure does not lead to asymmetric thrust problems.
4. Engines give some protection to the pilot, unlike "normal" twin.
5. There is no net torque so the plane is easy to handle.

 

[davparlr]

However you must also take into account improvements in power at higher altitudes due to engine (eg supercharger improvements) where the thinner air produces a linear increase in airspeed. I suspect relative pressures at the relative full pressure altitudes would give an indication of density and therefore speed increase.

I agree. It is just difficult with little data available. I think the plane was quite fast.

DonL
First, only the FW 187 V1 and V2 were single seater, all other 7 aircrafts were twin seater also the three A0 preproduction serie!

No room in the front, pilot cockpit, armament area, radar operator cockpit, now we have to install bulky radios and increasingly bulky radar equipment. And can you imagine the vibration problem of installing tube technology next to 20 mm cannons for the radar operator! No wonder they stuck with the He-219.

According to Mr. Hermann FW was always very accurate with all their project plans and calculations that were send to the RLM.

Engineering estimates always have uncertainties built in including round off errors, engineering tolerances, manufacturing tolerances, and testing tolerances (accuracies of wind tunnels, for instance). A previous post by a knowledgeable German poster stated that FW error estimate for engineering calculations was 4%, IIRC. This is probably typical. It certainly was not less than 2%.

FW was the company who didn't make promises that they can't hold and didn't do high gloss marketing with special prototypes or spackled prototypes!
All their calculation to the many aircrafts that goes in production were very accurate and the promised performances from their calculation were always reached from the production aircrafts.

So FW engineers believed they can built and develope a FW 187 two seater destroyer and nightfighter with the given datas, so I have no doubt that they can do this!

Wow, Germany did the incredible, invented perfect engineers.

Some explanations:

Good post on what you said.

The ammo for the 7.9mm MGs was behind the pilot. The 20mm guns were drum fed and under the floor or In the bottom 'corners' of the fuselage. I don't know if the rear seater had spare drums to reload the guns with as was done on the Bf110. As far as cockpit size goes the Fw 187 had 4-5 engine instruments mounted on each cowling above the exhaust because there wasn't room in the cockpit.
A big problem in trying to evaluate the Fw 187 is that the examples that did exist either used lower powered engines than intended or a rather experimental cooling setup. Trying to project performance forward to even bigger, heavier engines than were intended gets very complicated. The prototypes may have been overbuilt for their 740hp engines and needed no structural weight increase to use 100-1100hp engines. I am not sure the same could be said for going to the DB605. You not only have the weight if the engines but the bigger propellers, radiators, oil systems, etc. Increasing the gross weight of the plane buy several thousand pounds is going to compromise it's "G" rating with some structural beefing up. I am sure the Fw engineers could do the job. I also wonder if they really intended to use the exact same cockpit area on a proposed night fighter? There was no production tooling to "save". Adding 10CM in width or Height or both would not have been hard or extending the nose a bit. It was done on other planes and certainly was an option at the design stage. It does add a complication to simple performance estimates though.
We are left with the FW estimates which are probably better than anyone on this forum could do ( with perhaps a few exceptions,I am not one of them) but they are still estimates.
I do have the book quoted and while very interested a few details need a bit more clarification. Some ammunition load outs specified for some "paper" versions seem to be on the very generous side.

Good post. I think by the time all the modifications were done, it probably would not have performed much better than the Bf-110.

 

[jim]

My choice for twin would be the layout of the Do-335 because of:
1. Least drag.
2. Least rolling inertia.
3. Engine failure does not lead to asymmetric thrust problems.
4. Engines give some protection to the pilot, unlike "normal" twin.
5. There is no net torque so the plane is easy to handle.

Mr Timppa
no doubt in theory this layout had the greatest potentional. However Do 335 was very complex construction ( causing unreliability)and heavy. Considering a combat weight of 9000kgr ( no bombs) with DB603A means Wing loading of 233 kgr/m2 and power loading of 2,57 kgr/ps. Not great numbers in comparison with single seaters. It needed C3 fuel or Mw 50 (and even better both) to have a competitive power loading. That means late 44 the earliest by which time the coming Ta 152 offered similar performance at almost half the cost and fuel consuption.
However if Do335A could be put in production in January 43 instead of Me 410A would be a brilliant attack aircraft on the eastern front,and NF in west. Even bomber destroyer in west since most propably would be able to dive away from escort fighters. But i dont believe 335 would ever be able to dogfight with single engines like P38 did ( not always succesfuly)

 

[davebender]

There's another positive feature of a tandem engine arrangement which could be exploited.

Aerial refueling - Wikipedia, the free encyclopedia
Practical aerial refueling equipment and methods were created during the 1930s. However it was hazardous for most propellor driven aircraft due to risk of the fuel hose hitting a prop.

The Do-335 could fly using only the rear engine. Theoretically you could shut off the Do335 front engine and feather the prop which would allow safe aerial refueling. After fueling was completed the front engine would be restarted. Other tandem engine aircraft such as the Do-26 seaplane could do this also.

I have no idea if anyone would consider this for a WWII era combat aircraft but it offers interesting possibilities. They could top off with fuel immediately prior to entering enemy airspace.

 

[pbfoot]

Aeriel refuelling was being performed commercially by BOAC in the late 30's out of Gander Newfoundland enabling the Brit flying boats to cross the Atlantic