Heavy fighter: you are in charge

[davebender]

Neither did the F4U but both aircraft operated just fine from airfields on land. An aircraft that works well for the USMC would work equally well for the Army Air Force.

 

[Siegfried]

For general performance.
The Fw-187 seems no better than the contemporary Whirlwind, both would most likely have to add weight to make usable. All in all, both would be similar to the P-38, except in high altitude performance.

FW 187's with DB605A were supposedly capable of 440mph, way beyond the Whirwind and the 399.5 mph the Me 109G1 could accomplish with the same engine and some 395mph on the DB600 engine.

 

[Shortround6]

My idea for more 'P-38s' is pointed towards man-hours per a plane produced, more than towards any perceived lack of turbo set-ups.
The decreased maintenance should be also adding to the serviceable vs. available planes ratio (ie. more planes in combat for same number of on-hand ones). The two turbos deleted should make plane weight 600+ lbs less (same as 100 gals of fuel), so the climbing abilities would remain competitive. More so the short climbs during combat in lower altitudes with introduction of WER, some time in second half of 1942. The drag should go down since the airframe where once the turbine was would be far better streamlined (5 mph extra?).

Putting better intercoolers into the P-38 would have done more than anything else to improve it's performance in 1942/43. you also have the situation were models of the Allison engine tended to leapfrog each other by a number of months. The F2 engines in the very early P-38s (D's and E's) started production a number of moths before the F3s in the P-40D&E. Production contracts and tooling often were a year or more ahead of combat use. The F5 engines used in the P-38F passed their 150 hr test in may of 1941. NO WER ratings were for ANY engines were approved until late summer/fall of 1942.

The 109s were carrying some 100+ gals of fuel. With just extra 100 gals in wings (for 300 gals total, internal), the 109Z has useful range. So I'd give 270 gals of fuel

The early Bf 110s carried 336-340 US gallons in standard tanks and around another 140 in auxiliary tanks inside the wing. the Me 210 had 660 US gallons internal tankage. Granted the they had more drag but the Zwilling is not going to do some of the same jobs.

 

[tomo pauk]

The suggestion was aimed to increase number of P-38s all together if possible (producing both turboed and non-turboed version). Sure enough, better intercoolers would've helped. I'm aware when WER was introduced historically, and acknowledged it in post #76 here.

109Z would be way smaller lighter than 110 or 210, hopefully better suited for jobs in Reich defence (in day night fighter versions), with longer legs vs. real 109s. If LW really needs bigger planes, with bigger fuel tankage, with great performance, then 2 x 1300-1500 HP is hardly sufficient. Even 2 x 1750 did not help the 410 to become a performer.

Hi, Sigfried,

FW 187's with DB605A were supposedly capable of 440mph, way beyond the Whirwind and the 399.5 mph the Me 109G1 could accomplish with the same engine and some 395mph on the DB600 engine.

Would it be that you are comparing the (unbuilt) 3000 HP Fw-187 with (real) 1750 HP Whirlwind? What plane was capable to make 395 mph with DB-600 on board?

 

[davebender]

I should hope so. The Me-109Z was a fighter aircraft. The Me-210C was a light bomber. Rather like comparing a P-38 with an A-20.

 

[DonL]

Some datas and sources for the FW 187

Think the Fw-187 (or any other heavy fighter Germans would've fielded) with 8 x MG-17 would've fared just fine in 1940 - 400-500 rpg, guns centrally mounted.

The preproduction serie FW 187 A0 (3 planes) had 4 x 7,92-mm-MG 17 and two 20-mm-Maschinenkanonen MG/FF
This three planes were at combat missions in Norway, Denmark and Bremen!

All FW 187 planes ever built; FW 187 V1, V2, V3, V4, V5, V6 and three A0! In summary 9 planes.

The Fw187 which achieved that speed was using surface/evaporative cooling - negating a lot of drag. However, such systems didn't work in production machinery - though they worked well in racing/record breaking aircraft.

The Fw187 system, as I understand it, was much the same as used on the Schneider Trophy races. A closed system evaporative cooling system with surface radiatiors/condensors.

This is wrong and a translation error!
The FW 187 had never a surface/evaporative cooling

"Dampfheißkühlung"!: From the book Focke-Wulf FW 187: An Illustrated History Page 73 (german version)
"Das Prinzip kann vereinfacht so beschrieben werden: Das vom Motor benötigte Kühlwasser wird unter Druck gesetzt, um das Triebwerk mit höheren Temperaturen fahren zu können. Um dabei Dampfblasen zu vermeiden, wird aber zusätzlich ein zentrifugal-Dampfabscheider benötigt."
Translation:
"The principle can be described as simplified. The amount of cooling water from the engine is put under pressure to drive the engine at higher temperatures. In order to avoid vapor/steam bubbles youd are in need of a centrifugal Steam-separator (Dampfabschneider)."

Kyrill von Gersdorff / Schubert / Ebert "Flugmotoren und Strahltriebwerke" Seite 203 / 204
"Heißdampfkühlung":
"Die Flüssigkeitskühlung der deutschen Hochleistungstriebwerke ist in den 40er Jahren durchweg als Überdrucksystem ausgebildet. Dazu gehören ein im Nebenstrom liegender Vorratsbehälter mit Überdruck/Unterdruckventil und eine Entlüftung mit Dampf-Luft-Abscheider.
...
Daimler-Benz führt 1941 mit dem DB 605 das bereits auf DB-601-Rekordmotoren erprobte Überdrucksystem in die Serie ein.
...
Junkers wendet seit 1938/39 bei den ersten Baureihen des Jumo 211 ein System mit 0,3 bis 0,4 bar Überdruck an. Glykolzusatz ist nur für Winterbetrieb vorgeschrieben. Höchsttemperatur am Motoraustritt bis 95°C in Bodennähe zulässig. Mit dem leistungsgesteigerten Jumo 211 F kommt das neue Überdrucksystem erstmals zum Einsatz, die "Preßwasserkühlung", die dann mit dem Jumo 213 1942 in Großserie geht."
Translation:
"The liquid cooling of the German high-performance engines in the 40s consistently designed as positive/high pressure system. This includes at the secondary flow a reservoir with pressure / vacuum relief valve and a vent with steam-air separator.
...
Daimler-Benz introduced in 1941, the DB 605a with the already proven overpressure system of the DB-601 R (record engines) in the series.
...
Junkers used since 1938/39 on the first series of the Jumo 211, a system of 0.3 to 0.4 at elevated pressure. Glycol addition is required only for winter use. Maximum temperature at outlet permitted to 95 ° C near the ground. With the uprated Jumo 211 F, the new pressure system is first used, the "Preßwasserkühlung" (pressure water cooling)which then goes with the Jumo 213 in 1942 in volume production. "

The systems as used on the Me209 and He100 were total loss systems - the cooling fluid exited the aircraft as steam never to be used again.

This is correct for the world record planes (HE 100 V8 ), but wrong for the normal He 100 till the He 100D.
All He 100 except the D had a closed evaporative cooling system where the cooling liquid is running through the wings and will evaporate at the wing surface.

IIRC the HE112 was also originally fitted with such a system, though it was later changed for a conventional radiator.

No, only the He 100 had such a system and the He 100D was later changed for a conventional radiator

In summary the flight of the Fw 187 V5(WNr. 1976) with two DB 601a at October 1939 with 635km/h at level flight near the ground was with a high pressure cooling with very small coolers. The DB 601a wasn't fit for this high pressure cooling but the later DB 605a had the same technics through the Steam-air separator and the pressure water/glycol cooling.

The FW 187 V5 was flying till the end of 1942 in different conditions with differnt coolers, based on this data are the projects from FW of the 187 as Destroyer and Nightfighter and as clean Heavy Fighter/Longrange Fighter from 1942.

Source: Focke-Wulf FW 187: An Illustrated History/Dietmar Hermann/Peter Petrick

The idea of swapping the engines of the Fw187 to DB605 sound easy but I am willing to bet that a change like that would add a lot more weight to the aircraft.

The standard P38 of the time was at least 30 mph faster than the Fw-187 and also climbed better. The P38K was said to do 432 omh in level flight on military power and was guessed to be over 450 on WEP. It was also said to have had a ceiling of nearly 50,000 ft and climb at 4,800 fpm on military power and thought to be over 5,000 fpm on WEP. The P38 also had sufficient firepower for it's intended targets and could have been armed with cannon if needed. Money, at that time, meant nothing to the US, we were out to win.

So exactly what advantage did the Fw-187 have over even the standard P38?

According from the book of Dietmar Hermann/Peter Petrick there are completely calculated projects and the weight gain of the Bf 110 B to C to E to F are good examples for the weight gain of the FW 187.

Two seater destroyer variants.
FW 187 A0 (2 x Jumo 210g): empty: 3700kg full load: 5000kg (preproduction serie)
Estimated:
FW 187 "B0" (2x DB 601a) empty: 4200kg full load: 5500kg (weight gain 500kg -> Bf 110B (Jumo 210g, 6250kg) to Bf 110C (BD 601a,6750kg )
FW 187 "C0" (2 x Db 601E) empty 4800kg full load: 6200kg (DB 601 E is heavier then the DB 605a with equipment and thicker armor)
Calculated:
FW 187 "D0" destroyer and nightfighter full calculated project from FW 1942 with plans to the RLM/ordered by RLM but canceled 1943

weight: 7000kg loaded; 2 x DB 605A (2 x 1475PS), wing span 30m², payload to 8200kg (bombs, external fuel tanks, external weapons), internal fuel capacity 1300 liter; fuselage 880 Liter (increased to the A0) wings 210liter each; armor 167 kg; 4 x MG151/20 with 250 bullets - rigidly to the front, 2 x MG131 with 450 bullets - rigidly to the back, range 1200 km to 1.330 km,
Calculated with 6650 kg:
max speed at 7100m 685km/h, max speed near ground 547km/h, climb rate near ground 18m/s, climb time 0,9 min/1,0 km, 1,7 min/2,0 km, 3,6 min/4,0 km, 5,7 min/6,0 km .

FW 187 "X" single seater clean fighter/long range fighter full calculated project from FW 1942 with plans to the RLM/ordered by RLM but canceled 1943

weight: 6350kg loaded, 2 x DB 605A( 2x 1475PS), wing span 30m², internal fuel 1300 liter, 4 x MG151/20
Calculated with 6050 kg:
max speed at 7100m 725km/h, climb rate near ground 21,2 m/s, climb time 10,6 min/10 km

Source: Focke-Wulf FW 187: An Illustrated History/Dietmar Hermann/Peter Petrick

I rather suspect that the FW 187 would have had its fuel capacity increased over the initial 1100, the Me 110 and P-38 did recieve increases.

Fuel capacity was increased to 1300 liters

I estimate the range of the FW 187 at maximum cruise as about 700 miles: about 1.5 times that of the Me 109 plus 10% for its superior speed and 5-10% for the lower proportion of the journey spent in climb. With drop tanks this open up the possibillity of sustained opperations out to 330 miles from base; something the Luftwaffe didn't have moreover unlike the P-38 it could have been ready by by wars begining.

Estimated range from FW 1200 km to 1.330 km accordind to 0,85 and 1,15 ata

 

[davparlr]

FW 187's with DB605A were supposedly capable of 440mph, way beyond the Whirwind and the 399.5 mph the Me 109G1 could accomplish with the same engine and some 395mph on the DB600 engine.

The Fw-187 with 670 hp engines had a max speed of 326 mph. The Whirlwind, with 885 hp engines had a max speed of 360 mph. Increasing the Fw-187's engines to 885 hp and calculating the effect on airspeed generates an airspeed of 358 mph, or equal to the Whirlwind. The planes were almost identical aerodynamically. Putting engines in the Whirlwind equivalent to the DB605 would generate similar airspeed.

Calculating airspeed of an Fw-187 with a Bf-109G-6 engine (1475 hp), based on the above performance, gives 424 mph. Still quite impressive. However, these are very light. Removing one engine from the weight, they are very close to the Bf-109. The Fw-187 was 70% of the Bf-110 weight. Probably too small to be considered heavy fighters.

 

[DonL]

@ davparir

Putting engines in the Whirlwind equivalent to the DB605 would generate similar airspeed.

To my sources it was not possible without major reconstruction to put the Merlin engines to the Whirlwind.
The Whirlwind was developed and constructed to the Peregrine engines.

The FW 187 was constructed from the scratch for the 35 Liter 1000PS engines DB 601 and Jumo 211 (advetisement of the destroyer)
Only of the shortcomings of the DB 601 engines at 1938, the FW 187 A0 was built with Jumo 210g engines.

Calculating airspeed of an Fw-187 with a Fw-109G-6 engine (1475 hp), based on the above performance, gives 424 mph.

For the twin seater destroyer and nightfighter.
For the single seater Heavy fighter/Long range fighter it was calculated with 725km/h (450mph)

However, these are very light. Removing one engine from the weight, they are very close to the Bf-109. The Fw-187 was 70% of the Bf-110 weight. Probably too small to be considered heavy fighters.

What do you are considering as heavy fighter?
The FW 187 projects had all 4 x 151/20 cannons, this is three times the firepower of the Bf 109, and the payload was till 8200kg. Why is this not a heavy fighter?

Edit:
Even the A0 had 2 x 20mm cannons and 4x MG, thats two times of the firepower of the Bf 109 at the same timeline.

 

[Shortround6]

I really do like the Whirlwind but it was not a heavy fighter. A 250sq ft wing is just too small. and 8300lbs empty shows where if falls compared to later single engine planes. More could have been done withit but it was never going to be a night fighter with a second seat, a long range escort fighter or some of the other jobs that bigger fighters did.

 

[wuzak]

This is wrong and a translation error!
The FW 187 had never a surface/evaporative cooling

"Dampfheißkühlung"!: From the book Focke-Wulf FW 187: An Illustrated History Page 73 (german version)
"Das Prinzip kann vereinfacht so beschrieben werden: Das vom Motor benötigte Kühlwasser wird unter Druck gesetzt, um das Triebwerk mit höheren Temperaturen fahren zu können. Um dabei Dampfblasen zu vermeiden, wird aber zusätzlich ein zentrifugal-Dampfabscheider benötigt."
Translation:
"The principle can be described as simplified. The amount of cooling water from the engine is put under pressure to drive the engine at higher temperatures. In order to avoid vapor/steam bubbles youd are in need of a centrifugal Steam-separator (Dampfabschneider)."

Kyrill von Gersdorff / Schubert / Ebert "Flugmotoren und Strahltriebwerke" Seite 203 / 204
"Heißdampfkühlung":
"Die Flüssigkeitskühlung der deutschen Hochleistungstriebwerke ist in den 40er Jahren durchweg als Überdrucksystem ausgebildet. Dazu gehören ein im Nebenstrom liegender Vorratsbehälter mit Überdruck/Unterdruckventil und eine Entlüftung mit Dampf-Luft-Abscheider.
...
Daimler-Benz führt 1941 mit dem DB 605 das bereits auf DB-601-Rekordmotoren erprobte Überdrucksystem in die Serie ein.
...
Junkers wendet seit 1938/39 bei den ersten Baureihen des Jumo 211 ein System mit 0,3 bis 0,4 bar Überdruck an. Glykolzusatz ist nur für Winterbetrieb vorgeschrieben. Höchsttemperatur am Motoraustritt bis 95°C in Bodennähe zulässig. Mit dem leistungsgesteigerten Jumo 211 F kommt das neue Überdrucksystem erstmals zum Einsatz, die "Preßwasserkühlung", die dann mit dem Jumo 213 1942 in Großserie geht."
Translation:
"The liquid cooling of the German high-performance engines in the 40s consistently designed as positive/high pressure system. This includes at the secondary flow a reservoir with pressure / vacuum relief valve and a vent with steam-air separator.
...
Daimler-Benz introduced in 1941, the DB 605a with the already proven overpressure system of the DB-601 R (record engines) in the series.
...
Junkers used since 1938/39 on the first series of the Jumo 211, a system of 0.3 to 0.4 at elevated pressure. Glycol addition is required only for winter use. Maximum temperature at outlet permitted to 95 ° C near the ground. With the uprated Jumo 211 F, the new pressure system is first used, the "Preßwasserkühlung" (pressure water cooling)which then goes with the Jumo 213 in 1942 in volume production. "



This is correct for the world record planes (HE 100 V8 ), but wrong for the normal He 100 till the He 100D.
All He 100 except the D had a closed evaporative cooling system where the cooling liquid is running through the wings and will evaporate at the wing surface.


No, only the He 100 had such a system and the He 100D was later changed for a conventional radiator

In summary the flight of the Fw 187 V5(WNr. 1976) with two DB 601a at October 1939 with 635km/h at level flight near the ground was with a high pressure cooling with very small coolers. The DB 601a wasn't fit for this high pressure cooling but the later DB 605a had the same technics through the Steam-air separator and the pressure water/glycol cooling.

If the evaporative cooling system is closed loop then the steam will be condensed back to water in the wing surface radiators.

So, you are saying that there wa sno surcae radiators at all on the Fw187? Just small radiators?

 

[DonL]

So, you are saying that there wa sno surcae radiators at all on the Fw187? Just small radiators?

Yes my books say that, and Focke-Wulf FW 187: An Illustrated History/Dietmar Hermann/Peter Petrick is the reference book to the FW 187!
Mr. Hermann had done the most research on this plane and had the material what is available!

Also the translation of the independent words has an other meaning.

Oberflächenverdampfungskühlung -> Oberfläche-> surface -> Verdampfung-> evaporation-> Kühlung -> cooling.

"Dampfheißkühlung" -> Dampf -> steam -> heiß -> hot -> Kühlung -> cooling.

At the german documents of the FW 187 stand "Dampfheißkühlung" and at the documents of the He 100 stand "Oberflächenverdampfungskühlung".

Also at which surface of the FW 187 should the water evaporate/cooling?
The FW 187 had no wings with water cooling lines.

 

[Juha]

Hello Don
thanks for the interesting info on Fw-187. I have a couple questions.

...The preproduction serie FW 187 A0 (3 planes) had 4 x 7,92-mm-MG 17 and two 20-mm-Maschinenkanonen MG/FF
This three planes were at combat missions in Norway, Denmark and Bremen!...

But were they ever in contact with enemy planes? Or achieved they any kills?

...In summary the flight of the Fw 187 V5(WNr. 1976) with two DB 601a at October 1939 with 635km/h at level flight near the ground was with a high pressure cooling with very small coolers. The DB 601a wasn't fit for this high pressure cooling but the later DB 605a had the same technics through the Steam-air separator and the pressure water/glycol cooling.

So was the V5 max speed flown with coolers that would have been too small for practical combat plane, ie too small for ex a long climb in summertime.

...The FW 187 V5 was flying till the end of 1942 in different conditions with differnt coolers, based on this data are the projects from FW of the 187 as Destroyer and Nightfighter and as clean Heavy Fighter/Longrange Fighter from 1942.

Source: Focke-Wulf FW 187: An Illustrated History/Dietmar Hermann/Peter Petrick

IIRC RLM studied briefly Fw-187 as nightfighter in 42 but reached rapidly conclusion that it was too small for that, not enough space for radar and other electronics.

Juha

 

[Juha]

FW 187's with DB605A were supposedly capable of 440mph, way beyond the Whirwind and the 399.5 mph the Me 109G1 could accomplish with the same engine and some 395mph on the DB600 engine.

Now Westland made calculations for Whirlwind Mk II at the beginning of 1940 (belt fed Hispanos, 60 imp.gals more fuel etc plus 100-octane R-R Peregrines) TAS 354 mph at 5,000ft and 422mph at 20,000ft, 7.4min to 20,000ft.

Source: Bowyer's Interceptor fighters

Juha

 

[cimmex]

Yes my books say that, and Focke-Wulf FW 187: An Illustrated History/Dietmar Hermann/Peter Petrick is the reference book to the FW 187!
Mr. Hermann had done the most research on this plane and had the material what is available!

Also the translation of the independent words has an other meaning.

Oberflächenverdampfungskühlung -> Oberfläche-> surface -> Verdampfung-> evaporation-> Kühlung -> cooling.

"Dampfheißkühlung" -> Dampf -> steam -> heiß -> hot -> Kühlung -> cooling.

In the german documents of the FW 187 stand "Dampfheißkühlung" and at the documents of the He 100 stand "Oberflächenverdampfungskühlung".

Also at which surface of the FW 187 should the water evaporate/cooling?
The FW 187 had no wings with water cooling lines.

I would go with Dietmar Hemann too, no doubt he is the best Focke Wulf expert around and has access to very rare original documents
cimmex

 

[DonL]

@ Juha

I have emailed with Mr. Hermann and had near the same questions. I can only repeat his answers.

But were they ever in contact with enemy planes? Or achieved they any kills?

There are rumors that a FW 187 A0 had shot down a Spitfire at Norway at 1942 and in general the pilots who tested the FW 187 prefered the FW 187 A0 over the Bf 110C, but there is no document available to prove this rumors, also it can be a myth. Mr. Hermann had not found any pilot a life that confirmed this and so this information are not proved.

So was the V5 max speed flown with coolers that would have been too small for practical combat plane, ie too small for ex a long climb in summertime.

Yes, the coolers had problems at the taxiway, on the ground (to warm up the engine) and at very slow flight's less then 250km/h.
The "Dampfheißkühlung" was an experimental cooling from FW, but the conclusions and technics were introduced in the next generation engines DB 605, DB 603 and Jumo 213 through the steam/air seperator.

IIRC RLM studied briefly Fw-187 as nightfighter in 42 but reached rapidly conclusion that it was too small for that, not enough space for radar and other electronics.

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.

 

[Juha]

Hello Don
thanks a lot for the answers!
On the RLM and Fw-187 nightfighter, IIRC I read the myth from Kay's and Smith's book on LW planes published maybe in 80s, but as You wrote, Hermann is the Fw specialist, so I tend to believe him on questions on Fw fighters.

Thankfully
Juha

EDIT: After all it was William Green's Famous Fighters (1975), from which I got the info, Green gives as his source "the evaluation report of the Chief of Department C-E2".

 

[spicmart]

Calculating airspeed of an Fw-187 with a Bf-109G-6 engine (1475 hp), based on the above performance, gives 424 mph. Still quite impressive. However, these are very light. Removing one engine from the weight, they are very close to the Bf-109. The Fw-187 was 70% of the Bf-110 weight. Probably too small to be considered heavy fighters.

The de Havilland Hornet has similar dimensions as the Fw 187 and is considered a single seat heavy fighter. Why should the Fw 187 not be considered as such? With periodic airframe updates as Mr. Davebender mentioned it could have been developed into what the Hornet was.
The Fw 187 was intended to be a two seat destroyer after all, which is generally heavier than a heavy fighter.
Also the Merlin has similar weight and dimensions as the DB 605.

 

[davparlr]

@ davparir


To my sources it was not possible without major reconstruction to put the Merlin engines to the Whirlwind.
The Whirlwind was developed and constructed to the Peregrine engines.

I suspect it would have not been an unusual modification

For the twin seater destroyer and nightfighter.
For the single seater Heavy fighter/Long range fighter it was calculated with 725km/h (450mph)

424 mph was the results of my calculations. Horsepower goes up at cube of the power (double the speed requires eight times the power). Using a speed of 326 mph with a total of 1340 hp and increasing speed to 450 mph would require engines producing 1726 hp each, something I don't think the DB605A was doing in 1942.

 

[davebender]

RLM cancelled the Ju-252 and Me-210C during 1942 for no apparent reason. They also cancelled the Jumo222 engine just as it was about to enter production. So I wouldn't place too much weight on their evaluation of the Fw-187 during the same time frame. RLM wasn't thinking too clearly during 1942.

 

[Siegfried]

I suspect it would have not been an unusual modification

424 mph was the results of my calculations. Horsepower goes up at cube of the power (double the speed requires eight times the power). Using a speed of 326 mph with a total of 1340 hp and increasing speed to 450 mph would require engines producing 1726 hp each, something I don't think the DB605A was doing in 1942.

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.