BMW 139 information

[Hardrada55]

BMW 139 was the first engine installed on the prototype Fw 190V1. Was this engine a 14 cylinder or 18 cylinder engine? I have seen it cited before as a 14 cylinder engine and other sources say it was an 18 cylinder engine. Seeing as how the BMW 139 was developed from a 9 cylinder engine, I suspect the BMW 139 was an 18 cylinder engine. But which is true? I have also seen the engine displacement usually given as 55.378 Liters and once as 38 Liters. Which is correct? Horsepower is usually cited as 1550hp, but I have also seen 1400hp quoted. Does anyone have dry weight and dimensions? Any information would be received with gratitude.

 

[HoHun]

Hi Hardrada,

From von Gersdorff et al.:

BMW 139: 14 cylinder injection engine, forced-induction air cooling, 155.5 m bore, 155.5 mm stroke, 41.2 L displacement, 1500 HP @ 2700 rpm, maximum continuous 1150 HP @ 2000 rpm @ 5.4 km at 225 g/HPh specific consumption.

There was an 18 cylinder BMW 140, which was projected but not developed in 1937.

From the Rüst- und Betriebsanleitung Fw 190V-1 u. V-2:

BMW 139, injection engine

Power:

Increased short-term power (1 min): 1500 HP (take-off power)
Short-term power (5 min): 1410 HP at 4500 m altitude
Increased short-term power (30 min): 1270 HP at 4900 m altitude
Continuous power: 1150 HP at 5400 m

Weight:

Engine without additional equipment, with ventilator wheel: 800 kg

Propeller:

3.3 m diameter VDM propeller with light-alloy blades

Regards,

Henning (HoHun)

 

[Hardrada55]

Many thanks for the excellent information!

 

[Hardrada55]

How about information about the Bramo 329? Basic stuff. Number of cylinders, displacement, basic horse power information. Thanks

 

[HoHun]

Hi Hardrada,

>How about information about the Bramo 329? Basic stuff. Number of cylinders, displacement, basic horse power information.

Again from von Gersdorff et al.:

Bramo 329

14 cylinders, 154 mm bore, 154 mm stroke, 40.2 L displacement, two-speed single-stage supercharger, reduction gear, 1500 HP @ sea level at 2600 rpm.

I'm afraid it's not much, but the engine was cancelled in 1938 when BMW entered a cooperation with Bramo. The BMW 132 was cancelled at the same time, and the BMW 801 resulted from the cooperation (which seems to have been more of a merger, I think, but von Gersdorff et al. specifically mention a cooperation contract). The single-lever control for example had been a feature of the Bramo engines even before the war.

Regards,

Henning (HoHun)

 

[Stephan Wilkinson]

I'm looking at a photo of the BMW 139 in Wolfgang Wagner's authoritative book on Kurt Tank, and it's an 18, not a 14.

 

[Burmese Bandit]

And wiki says that it had 18 cylinders...

 

[hrandy]

BMW recent book "BMW aero engines" states in several places that the BMW 139 was a 14 cylinder engine. It lists the dimensions of the cylinders as 155.5 mm by 155.0 mm (very close to HoHuns' source) which gives 41.2 litres in 14 cylinders or 52.98 litres in 18 cylinders. I think it's obvious that the smaller displacement is correct.

This makes me wonder what 18 cylinder engine is picture in Mr. Wagners' book. It is so easy to makes mistakes and they tend to be perpetuated forever.

 

[davebender]

BMW 139:
1500 HP @ 2700 rpm
800 kg without additional equipment

1940 BMW801 prototype
1,539 hp
1,088 kg.

DB603A V12 engine
1,750 hp
920 kg.

Why was BMW so enamored with air cooled engines? From the mid 1920s until the mid 1930s the BMW VI V12 dominated the German aircraft engine market. You would think they would use their experience with V12s to produce a modern V12 to compete with the 1,750 hp DB603 engine.

 

[krieghund]

looking for the data from "Aircraft Engines of the World" 1941 by Paul Wilkinson

 

[Shortround6]

BMW 139:
1500 HP @ 2700 rpm
800 kg without additional equipment

1940 BMW801 prototype
1,539 hp
1,088 kg.

DB603A V12 engine
1,750 hp
920 kg.

Why was BMW so enamored with air cooled engines? From the mid 1920s until the mid 1930s the BMW VI V12 dominated the German aircraft engine market. You would think they would use their experience with V12s to produce a modern V12 to compete with the 1,750 hp DB603 engine.

The two BMW prototypes are several years earlier in timing than the DB 603A. And no, the record breaking car engine doesn't count. The British could get over 2000hp out of a racing Merlin at the same time the 603 was in the car.

Add at least a hundred kilos to the 603s weight for radiators and coolant.

BMWs V-12 "experience" was basically using a pair of WW I 6 cylinder engines on a common crankshaft.
The Russians did use the BMW 12 as a staring point for the AM-35 and 38 engines but there was precious little left of the BMW design by the time they got through.
BMW had designed and built another V-12 in the 30s. The 116 but it was 20 liter engine in the same class as a Jumo 210.

The 139 is not in the 1941 edition of Wilkinson's.

 

[davebender]

The 1930 RLM specifications called for a 35 liter engine. During the early 1930s BMW had more experience with V12s then either Junkers or Daimler-Benz. Why didn't BMW compete for the new V12 contract?

 

[Shortround6]

The 1930 RLM specifications called for a 35 liter engine. During the early 1930s BMW had more experience with V12s then either Junkers or Daimler-Benz. Why didn't BMW compete for the new V12 contract?

Maybe their engineers had a change of heart or maybe thy figured they would have better sales success as the ONLY high powered air cooled engine instead of being one company splitting the V-12 market 3 ways.

Here is BMWs V-12 engine that powered thousands of early Luftwaffe aircraft.

BMW VI - Wikipedia, the free encyclopedia

Please note that it is a 45-46 liter engine. There is little scope in increasing rpm or in fitting a supercharger to increase power. The crankcase and cylinder assembly just aren't rigid enough to support much higher crank loads or cylinder pressures.
Please look at what the Soviets had to do to turn it into the AM-34 during the early-mid 30s.
The RLM also wanted an inverted engine. Turning an engine over is a lot harder than it sounds. Oil flows and coolant flows have to worked out all over again.
Everything considered they were going to have to make a brand new engine one way or another. Why not start with the 1926-7 P&W Hornet they were making under licence rather than the their own VI which could trace back to the III of 1916-17.

 

[davebender]

Why not start with the 1926-7 P&W Hornet they were making

That engine was just as obsolete as the BMW VI V12. Obtaining enough hp to compete with a modern water cooled V12 required a twin radial and that is a very different animal.

If BMW had obtained a license for the 30 liter P&W R-1830 twin radial it would be a different story. It was as powerful as early models of the DB600 engine yet weighed less. Tweek it a bit and you get something like the P&W R-2000 twin radial which produced 1,300 hp fueled by 87 octane gasoline.

 

[Shortround6]

That engine was just as obsolete as the BMW VI V12. Obtaining enough hp to compete with a modern water cooled V12 required a twin radial and that is a very different animal.

If BMW had obtained a license for the 30 liter P&W R-1830 twin radial it would be a different story. It was as powerful as early models of the DB600 engine yet weighed less. Tweek it a bit and you get something like the P&W R-2000 twin radial which produced 1,300 hp fueled by 87 octane gasoline.

The Hornet was nowhere near as obsolete as the BMW V-12.
What engine designers did at the time in development work was design one cylinder and see what they could get for power from it. Then they multiplied the cylinder to get to the power they wanted. Granted that a two row radial presents a few more problems than a single row but that is the way that most air-cooled engines were developed. The Hornet (as the BMW 132) was developed to give 1200hp for take off but that was using fuel injection and water injection. Not too shabby for a 27.7 liter aircooled "obsolete" engine.
Shorten the stroke 6mm and use two rows of 7 instead of one row of 9 and what have you got?

Granted there is a bit more to it than that but trying to turn BMWs experience with the V-12 VI engine into anything useful in WWII would have taken even more work.

Just what model/year R-1830 are you comparing to what model/year of the DB 600?

 

[davebender]

Wikipedia. None the less probably still in the ballpark.
Pratt Whitney R-1830 - Wikipedia, the free encyclopedia
R-1830-1 - 800 hp (597 kW)
R-1830-9 - 850 hp (634 kW), 950 hp (708 kW)
R-1830-11 - 800 hp (597 kW)
R-1830-13 - 600 hp (447 kW), 900 hp (671 kW), 950 hp (708 kW), 1,050 hp (783 kW)
R-1830-17 - 1,200 hp (895 kW)
R-1830-21 - 1,200 hp (895 kW)
R-1830-25 - 1,100 hp (820 kW)
R-1830-33 - 1,200 hp (895 kW)
R-1830-35 - 1,200 hp (895 kW) Fitted with GE B-2 turbosupercharger
R-1830-41 - 1,200 hp (895 kW) Fitted with GE B-2 turbosupercharger

According to Pratt Whitney the R1830 entered production during 1932. 4 years before Daimler-Benz began building the first DB600 engine factory at Genshagen and 5 years before the DB600 engine entered mass production. I think BMW could have a variant of the R1830 in license production before the first DB600 engine rolls off the Genshagen assembly line. With a single speed supercharger and fuel injection the BMW R1830 ought to be good for 1,000 hp. As much as the DB600A engine. It would use the same production facilities as the historical BMW132 single radial engine.

 

[Shortround6]

According to Pratt Whitney the R1830 entered production during 1932. 4 years before Daimler-Benz began building the first DB600 engine factory at Genshagen and 5 years before the DB600 engine entered mass production. I think BMW could have a variant of the R1830 in license production before the first DB600 engine rolls off the Genshagen assembly line. With a single speed supercharger and fuel injection the BMW R1830 ought to be good for 1,000 hp. As much as the DB600A engine. It would use the same production facilities as the historical BMW132 single radial engine.

Something seems a bit off here. For an engine that entered production in 1932 the first use in a commercial certified aircraft seems to be summer/fall of 1935. The M-130 Martin China Clipper was issued it's ATC certification on 10-9-35. NO DC-2 used a R-1830 engine. A few may have been used in the Martin XB-14 bomber before this or prototype P-35s?

The engine in the China Clipper was rated at 830HP at 6000ft.
By the following fall (Nov 1936) the R-1830 was being installed in DC-3s with a Max continous rating of 900hp at 8,000ft and 1100hp for take -off.

IN 1937 the Luftwaffe was starting to order DB601 engines. DB 600s were being installed in HE 111b by the fall of 1936 (granted small numbers).

Nobody bought licences for prototype engines. Anybody who licensed an engine waited a few years to see how they did in service before plunking down any money. Co-production is a different story but that is not what we are talking about here.
Germany was not likely to get a license for the R-1830 in 1936 or 37 because Hitler was already making himself rather unpopular by that time.

 

[davebender]

Official Pratt Whitney Web Site.
R-1830 Twin Wasp
Production years: 1932-1951

I only know what the official Pratt Whitney web site says. Do you have historical production numbers for the P&W R1830 engine during the 1930s?

 

[cherry blossom]

If we look at the P&W site for the R-2800 Double Wasp, it gives Production years: 1939-1960. However, the F4U and B-26 first flew in 1940, entered production in 1941 and saw action from 1943 and 1942 respectively. Thus the production start is probably the year when they first made an engine that passed its tests for both engines. For the R-2800, first flight is given as 1939, so does anyone know how it was flight tested?

 

[davebender]

Probably in an aircraft other then a mass production installation. That's how Germany did things. For instance the Jumo004A jet engine first flight test on March 15, 1942 while installed in an Me-110.