Effect of operational Fw187s during the Battle of Britain

[stona]

Was common use day fighter as night fighter early in the war

True

Cheers

Steve

 

[wiking85]

It's not that simple. Factories and component suppliers must be retooled for the new aircraft model.

Goering created the night fighter force during 1940 without a lot of warning. Hence there were no factory made night fighter aircraft prior to mid 1941 or so. As an expedient most Me-110 day fighter aircraft plus a few Do-215s and Ju-88s were transfered from existing units.

IMO if we need expedient night fighter aircraft during 1940 then use Do-17s. Bomber units would hardly miss them and Dornier can keep existing production line in operation through 1941. During 1942 Germany can begin production of an aircraft specifically designed for the night fighter role. Design selection would be by flight competition.

Fw-187 mass production cost with DB601 engines was only RM 140,000. Less expensive then Ju-88 and Me-110. Minimizing Fw-187 production would be counter productive to the German war effort. We want to do the opposite. Give Fw-187 the recon role historically performed by more expensive Me-110 and Ju-88 in addition to long range day fighter mission. I would also experiment with a CAS variant that has a 3cm Mk101 or Mk103 cannon under fuselage.

Works for me.

 

[stona]

There was a shortage of DB 601 N engines in 1940,just not enough to go around and the RLM kept changing its mind about what should have them. Most Bf 110s didn't get them. Now the proposal is for a different twin engined type which needs them.

You'll need 700+ engines to equip your units with 300 Fw 187s and they didn't exist.

You can have your regular DB 601 powered aircraft

Cheers

Steve

 

[wiking85]

There was a shortage of DB 601 N engines in 1940,just not enough to go around and the RLM kept changing its mind about what should have them. Most Bf 110s didn't get them. Now the proposal is for a different twin engined type which needs them.

You'll need 800+ engines to equip your units with 300 Fw 187s and they didn't exist.

Cheers

Steve

As we mentioned earlier they would have DB601As or Bs, because IOTL the N (or P) wasn't available until August anyway. Nevertheless with a total of 2200hp with two Db601As at 1100hp each, the single seater Fw187 would still exceed 400mph at top speed.
The single seater was 500kg lighter than the two seater version whose stats are on Wikipedia and it would have 800hp more than that version as well.

As a rule of thumb with fighters a 100hp increase equals about 10mph increase. So 800hp more is 80mph more. Minus the 500kg, which is probably worth 5-10mph more. That gives us about 410-420 mph total with the single seater version with the DB601A/B.

And the Bf110 got the DB601P mostly, not the N.

 

[Aozora]

And the Bf110 got the DB601P mostly, not the N.

??? Please provide some references - apart from an unreferenced Wikipedia article - to prove this one.

 

[delcyros]

my impression is that 410 mph with 2x1200hp sounds a bit to high. 385mph makes more sense unless the airframe isn´t cleaned up (less drag). However, the bigger engine implies a heavier installation and airframe weight than the -187A, and inherently more cooling drag.

 

[wiking85]

??? Please provide some references - apart from an unreferenced Wikipedia article - to prove this one.

You got me there. I just have that quote for the moment.

my impression is that 410 mph with 2x1200hp sounds a bit to high. 385mph makes more sense unless the airframe isn´t cleaned up (less drag). However, the bigger engine implies a heavier installation and airframe weight than the -187A, and inherently more cooling drag.

The frame was designed with as clean a surface as possible.
Also it was designed around the Db600 engine, which was almost exactly the same size and weight as the Db601A.

 

[Aozora]

As we mentioned earlier they would have DB601As or Bs, because IOTL the N (or P) wasn't available until August anyway. Nevertheless with a total of 2200hp with two Db601As at 1100hp each, the single seater Fw187 would still exceed 400mph at top speed.
The single seater was 500kg lighter than the two seater version whose stats are on Wikipedia and it would have 800hp more than that version as well.

As a rule of thumb with fighters a 100hp increase equals about 10mph increase. So 800hp more is 80mph more. Minus the 500kg, which is probably worth 5-10mph more. That gives us about 410-420 mph total with the single seater version with the DB601A/B.

According to Focke-Wulf Fw 187: Deitmar Hermann, Peter Petrick the Fw 187 V-5 was tested with DB 601As fitted with low drag evaporator cooling and achieved 635 km/h (394 mph) at low altitude (page 78 ). With normal glycol radiators assume top speeds of about 380-390 mph at similar heights to Bf 109s.

 

[Glider]

They why didn't they have the Whirlwind?

The problems were with the Hydraylics and making the guns reliable. The engines were very reliable.

You might get a handful operational by October.

I agree with you. But you must agree thats a lot closer than the Fw187 got to combat. You shuld also remember that the Fw 187 you are quoting didn't have any armour, self sealing fuel tanks and other additions which would have added to the weight.
Before you ask, the Whirlwind was the first RAF aircraft to be designed with armour which formed part of the structural design.

Edit:
also looking at the stats, I don't think it is any better than the Spitfire, just with heavier firepower:

Again I agree with you. Most would agree that the Fire Power of 4 x 20mm was approx five times greater than the 8 x 303, plus you can add a factor for being concentrated in the nose, plus a bit more for the extra range by not having the guns converging at a set range. What was the biggest drawback of the Spit I and II, its firepower.
Put it another way, a number of German bombers made it home with 200+ hits, they often crash landed with casualties to the crew. Allowing for half the number of guns at half the ROF, that would be about 50/60 hits by a 20mm. Can you see any German bomber making it home with 50 20mm hits?

 

[wiking85]

According to Focke-Wulf Fw 187: Deitmar Hermann, Peter Petrick the Fw 187 V-5 was tested with DB 601As fitted with low drag evaporator cooling and achieved 635 km/h (394 mph) at low altitude (page 78 ). With normal glycol radiators assume top speeds of about 380-390 mph at similar heights to Bf 109s.

I don't have access to that book, so that would be about right...but the V5 was the heavier two seat version. It wasn't as aerodynamically clean thanks to having to enlarge the cockpit for the second man and add more armor for him.

Focke-Wulf Fw 187 - Wikipedia, the free encyclopedia

Even before V1 flew, Tank had been instructed to convert the design to a two-seater for this role, although the need for a second crewmember in this role was marginal. The first two prototypes were already well advanced in construction at this point, so they began with the third prototype, which had just begun construction.

Blaser adapted the design by stretching the fuselage only slightly, but this did have the effect of moving the center of gravity, which demanded the engine nacelles be modified to return the balance to the proper point in relation to the wing. A new extended-length cockpit with two crew members covered by a "framed" canopy was added, but due to the high line of the fuselage there was nowhere to put any defensive armament, reducing the second crewmember to the role of radio operator only.

Two additional two-seat prototypes, V4 (D-OSNP) and V5 (D-OTGN), followed in the summer and autumn of 1938 respectively.

IIRC the additional weight amounted to nearly 500kg and increased drag significantly.

Assuming that we keep the single seater version and never build the prototypes with the Jumos, instead sticking to the Db601s, even at nearly 400mph that is 40 mph faster than the Spitfire in August 1940. It also had about 1000 mile range IIRC, which is 2.5x as much as the Spitfire or Me109.

 

[wiking85]

The problems were with the Hydraylics and making the guns reliable. The engines were very reliable.


I agree with you. But you must agree thats a lot closer than the Fw187 got to combat.



Again I agree with you. Most would agree that the Fire Power of 4 x 20mm was approx five times greater than the 8 x 303, plus you can add a factor for being concentrated in the nose, plus a bit more for the extra range by not having the guns converging at a set range. What was the biggest drawback of the Spit I and II, its firepower.
Put it another way, a number of German bombers made it home with 200+ hits, they often crash landed with casualties to the crew. Allowing for half the number of guns at half the ROF, that would be about 50/60 hits by a 20mm. Can you see any German bomber making it home with 50 20mm hits?

The point is have a separate thread if you want to talk about the Whirlwind. This is about the Fw187. I agree that there is an interesting discussion to be had about the Whirlwind, but this isn't the place for that.

 

[tomo pauk]

What would be the weight of the Fw-187 with DBs?

 

[wiking85]

What would be the weight of the Fw-187 with DBs?

I think about 3300kg.

 

[tomo pauk]

Wikipedia gives 3700 kg, empty, for the Fw-187A-0 (Jumo 210), 3300 seem pretty low for DB version.

 

[fastmongrel]

As a rule of thumb with fighters a 100hp increase equals about 10mph increase. So 800hp more is 80mph more. Minus the 500kg, which is probably worth 5-10mph more. That gives us about 410-420 mph total with the single seater version with the DB601A/B.

Is it as simple as that. That means if the FW187 had 2,000 hp engines like a DH Hornet (which is roughly the same size though heavier) it would be doing 600mph.

 

[Shortround6]

As a rule of thumb with fighters a 100hp increase equals about 10mph increase. So 800hp more is 80mph more.

It is a poor rule of thumb. The cube law is a better rule of thumb. The Fw 187A did 329 mph at 13,780ft with about 675hp per engine. At least the engine was rated at 675hp at 12,500ft. Figure some extra altitude from the ram effect and it should be close enough. So 1350hp total. To hit 409mph (80 mph more) the cube law says you need just under 2600hp (2593.37). With 1100hp per engine and NO change in drag the cube law says it should hit 387mph.

At the moment I can't be bothered to pull the book on the Fw 187 but the difference in weight of 500kg between a single seater and the two seater is hard to credit. There were very few single seat prototypes and at least one had no guns at all and the other/s didn't carry the same armament as the two seaters. The Bf 109 also gained about 500lbs empty when it went from the Jumo engine to the DB engine so you get about a 1000lb increase by switching engines.

The Fw 187 may have been under appreciated and offered things that the 109 and 110 didn't but lets not get carried away with some of these estimates.



Minus the 500kg, which is probably worth 5-10mph more. .[/QUOTE]

 

[wiking85]

Wikipedia gives 3700 kg, empty, for the Fw-187A-0 (Jumo 210), 3300 seem pretty low for DB version.

That was the two seater version with the extra weight being for the extra crew member (100kg about with his weight, clothing, and gear), the extra armor, the rebalancing of the aircraft after extending the cockpit, and the greater overall size of the cockpit in the two seat version.
I'm talking about the single seat version with the DBs. If we go by the two seat version with DBs, then we already know that it would weigh about the same as the Jumo two seat version and have about 380-90mph.

 

[davebender]

30 to 40mph faster then other fighter aircraft during 1940. Superior climb and firepower too plus three times the internal fuel capacity of Me-109 and Spitfire.

Why are people splitting hairs over Fw-187 aerial performance? It's fantastic compared to contemporary fighter aircraft when powered by normal DB601 engines.

 

[wiking85]

It is a poor rule of thumb. The cube law is a better rule of thumb. The Fw 187A did 329 mph at 13,780ft with about 675hp per engine. At least the engine was rated at 675hp at 12,500ft. Figure some extra altitude from the ram effect and it should be close enough. So 1350hp total. To hit 409mph (80 mph more) the cube law says you need just under 2600hp (2593.37). With 1100hp per engine and NO change in drag the cube law says it should hit 387mph.

I'm not an aeronautics engineer, so I'll take your word for it. In fact I think I did read something like this once. So you are probably right.

At the moment I can't be bothered to pull the book on the Fw 187 but the difference in weight of 500kg between a single seater and the two seater is hard to credit. There were very few single seat prototypes and at least one had no guns at all and the other/s didn't carry the same armament as the two seaters. The Bf 109 also gained about 500lbs empty when it went from the Jumo engine to the DB engine so you get about a 1000lb increase by switching engines.

The Fw 187 may have been under appreciated and offered things that the 109 and 110 didn't but lets not get carried away with some of these estimates.

Minus the 500kg, which is probably worth 5-10mph more. .

I don't have a specialized book on the Fw187, so if you could help us with the numbers I would appreciate it.

For the sake of argument, let's say that the single seater version has a 385mph top speed. That's still 25 mph faster than the Spitfire of August 1940 and its far more nimble than the Bf110.

Edit:
The V1 prototype of the FW187, the single seater version weighed 10,000lbs loaded, compared to the A-0 two seater version, which weighed just over 11,000lbs.
Its not quite 500kg more, probably closer to 400kg.
This is according to William Green's "Warplanes of the Third Reich".

 

[tomo pauk]

12500 ft translates into 3875m, where the DB-601A makes ~1010 PS (5 min Kurzleistung - 'short term power') . The only height it makes more than 1100 PS is from SL (1100 PS) to 1,3km (1150 PS), Abflugleistung - 'take off power', 1 min duration. Of course, the altitude of power is crucial, full throttle height being 4 km, power 1020 PS.
The 601Aa and A1 were slightly different in power, Aa better down low, A1 a tad better at higher altitude.

power graph of DB-601A:

http://www.wwiiaircraftperformance.org/me109/db601a-curve.jpg