Napier keeps making liquid-cooled engines in 1930?

[tomo pauk]

In other words: no Rapier, no Dagger.
We can opt to make improved Lion, or a big W12 or V12 engine (30-40L?), or a H16, or a H24 (poppet valves) - whatever floats you boat. Point of the exercise being that RAF has more to choose from after 1935, and Napier having money and reasoning to make their production facilities more modern already before ww2.

 

[Shortround6]

Well, we have small problem. No real design team. And/or the small number of actual designers in Great Britain at the time.
The man who designed the Lion in 1917-18 had left Napier in 1921 and joined RR as the assistant to H. Royce. He is credited with helping design/develop the Condor, Kestrel, and developing the R. In 1933 with Royce's death he became the Chief Consultant.
Napier staggered along with the Lion.
They hired Frank Halford as an independent consultant and he is responsible for the Rapier, Dagger, later the Sabre. Halford had started in WW I with BHP and really made a name figuring out how to turn surplus air cooled V-8 engines into inline 4's for small two seat private plane/trainers. Later refined the idea into the DH Gypsy engine using new parts. This is also the basis for the Gypsy Major in 4 & 6 cylinder and Gypsy King 12. It is also the basis for a number of 4, 6, 8, 12 air cooled engines built across Europe.
Unfortunately his independent design office was right next door to Harry Ricardo's design office during the 1920s and the sleeve valve Kool Aid was in the atmosphere.

Now there was a 16 cylinder that cropped up during the early 20s at Napier.

The Cub, of about 60 liters and 2450lbs and a claimed 1000hp at 1800rpm.
I am not sure anybody claimed responsibility for this thing
"Production" stopped after 6 engines.

Somebody could have designed a 30-40liter V-12 and done an OK job of it. Problem with this that even without Hooker, RR was leading the pack in supercharger design in England in the 1930s. The RR engines were not particularly innovative in head/combustion chamber design. What RR was very good at was improving things and not sitting on their butts.
RR development strategy was pretty much summed up by "Flog it until it breaks, fix it, then flog it until the next thing breaks, fix it, repeat."
The early Merlin's had a lot of problems, RR had the lower level engineers and the ability (money) to redesign, fix, retool and keep going.

 

[ThomasP]

A 1000-1500 BHP class W12 could have been useful as an alternative to the Merlin for the bomber designs, where the slight increase in frontal cross-section would not have much of a practical effect.

Or, if the engine is in the Griffon+ class, you would have a basis for the next generation larger fighters. I would not think that a 2000 BHP W12 would be any draggier than a R-2800.

My understanding is that Napier's W12 Lion (1461 in3) design was a pretty solid engine - with good reliability and maintainability. Not sure what changes in size or design concepts would be needed in practical terms for a reliable 2000 BHP output vs the basic design of the 500-700 BHP Lion. IIRC the last of the Lion developments was running at ~1000 BHP in the design & test stage when they discontinued work on it.

The Supermarine S.5 was racing with a 875 BHP Lion in 1927, and they used the Lion (running at upto 3600 rpm and 1350 BHP) in the fast boat and land speed competitions, as well as the Schneider Competition of the late-20s & early-30s, so I would say the potential was probably there.

 

[Shortround6]

The Supermarine S.5 was racing with a 875 BHP Lion in 1927, and they used the Lion (running at 3600 rpm and 1350 BHP) in the fast boat and land speed competitions, as well as the Schneider Competition of the late-20s & early-30s, so I would say the potential was probably there.

The Lion was a 24 liter engine. It was also an under 1000lb engine. It needs a crap load of modifications to stay competitive in the 1930s let alone into WW II.

Two things were going on in the development of engines. One was the power output which is somewhat dependent on strength of the engine, as in can you get it to give 1300hp for several minutes without breaking. The other more hidden thing was also somewhat strength dependent. Can you get the thing to last XX number of hours before overhaul in service conditions.

The Lion was a terrific engine for 1917-1918, it sure beats the heck out the Liberty engine
It also stands up to inspection vs the BMW VI V-12 of the early 30s.
It also stands up to the Curtiss V-1570 of the late 20s.

Now perhaps you could enlarge it but it already was using pistons slightly larger than the Merlin or just about the same as an Allison. It used a short stroke which was good for high rpm.
But you have three cylinders acting on each crankpin and you have an uneven firing order. If you increase the stroke you increase the width of the engine which was on the wide side to begin with, 42 in. The engine used combination of separate cylinders with one piece cylinder head. The cylinders were one piece with a closed top with 4 holes for the valves. The cylinder head was joined to the cylinders in part by the valve seats which went into threaded holes which helped join the cylinders and heads together .

Very good article here

Napier Lion History

But for engine going into the late 30s and early 1940s you need something different.
The much larger (36 liter) Hispano 12Y is a cautionary tale about trying to use too light an engine to make high power.

 

[tomo pauk]

Me, I'd take a good look on the Curtiss D-12 and the V-1570, and try to scale these up, to at least 35 liters.

 

[Shortround6]

Me, I'd take a good look on the Curtiss D-12 and the V-1570, and try to scale these up, to at least 35 liters.

Does this really gain anything over simply building another factory for the Merlin?

The V-1570 used 130 X 161 mm cylinders.
The D-12 was older and used 114.3 X 152.4 cylinders.

More modern engines tended to be less under square. (Hispano engines were not modern).
2400rpm was a rough limit as the rpm that could be run without using serious counterweighting on the crankshaft.
A few of the V-1570s did get counterweighting, late model V-1570s had other improvements and wound up between 1000-1100lbs.


Actually, force RR (gun point or Prison and Prison might not have convinced them) to give Napier the blueprints for the Buzzard. Go from there.

 

[tomo pauk]

Does this really gain anything over simply building another factory for the Merlin?

We should be aiming at more power, and I'm willing to pay the price in weight & bulk of the engine to get there.

Actually, force RR (gun point or Prison and Prison might not have convinced them) to give Napier the blueprints for the Buzzard. Go from there.

Napier continuing on from the Buzzard on seems like an excellent idea.

 

[ThomasP]

Buzzard --> Griffon I --> Griffon II is an interesting idea to avoid production conflict problems at the start of the war. Successful development of the engine could solve the problem of the Tornado/Typhoon and Firefly/Barracuda delays (maybe?). I do not know if getting the 2 companies to work together in a worthwhile manner would have been practical in the real timeline?

Otherwise, I still think a development of the Napier W12 design into the 1500 and/or 2000 BHP range would have been viable. Presumably Napier would have moved on to sleeved aluminum cylinder water jacket banks like the other engine makers (ie no more individual cylinders) and further developed their 4-valve head arrangement. I do not have accurate dimensions for the Lion but from approximate scaling of drawings an enlarged Lion would fit in about the same diameter as the R-2800. Whether they used the inverted W12 layout of the type E71 Lioness or stuck with the normal orientation and put up with the reduced forward view over the nose (as in the large radial engined airframes) I think it would have been a good fit through the Tornado/Typhoon period at least. Obviously, this would require that the Air Ministry actual put out a request for such an engine early enough.

As in the Napier Buzzard/Griffon alternate timeline, development of a 1500 BHP W12 would relieve pressure on RR, at least where the Merlin and Griffon development and production were concerned. The W12s could be used in place of the Merlin for the Halifax and Lancaster, freeing up the Merlin XX production for projects like the Spitfire Mk III.

If the ATL Napier W12s were similarly developed to the Merlin XX and later series, they should be capable of more power than the Merlin lb-for-lb.

Given how advanced the Lion of the 1920s and early-1930s was, relative to other engines, maybe Napier would have taught RR a few things.

 

[z42]

Ok, here's my scenario: Napier takes the Culverin (license produced Jumo 204) and develops it into a series of engines suitable for tanks and small boats like MTB's, MGB's, etc. Hey, why not develop the Deltic while we're at it? With no need for the RR Meteor, RR can devote their resources into the Merlin and Griffon.

 

[Shortround6]

engines suitable for tanks and small boats like MTB's, MGB's, etc.

It is too much of one thing and not enough of the other.
The need for a 600-800hp diesel engine in tanks for British tanks in the 1930s was non-existent. Assuming you could even get the thing to work. Which took years in the 1960s for the Chieftain. Of course in the Chieftain they also flopped the thing in it's side, trying to figure out how to hide a 1.5 meter tall engine in a tank hull is bit tricky.
For MTBs you need about 6 of them per boat, or more?
MTBs have different power requirement than aircraft engines which means the boat engines are de-rated. Their engines are rated at 1 hour (?) or 4 hours not 5 minutes or 15 minutes.

The Germans used V-16/20 cylinder engines developed from Zeppelin engines.

 

[z42]

The need for a 600-800hp diesel engine in tanks for British tanks in the 1930s was non-existent.

So derate the initial version(s). For a British WWII tank 500 hp ought to be sufficient.

Assuming you could even get the thing to work. Which took years in the 1960s for the Chieftain. Of course in the Chieftain they also flopped the thing in it's side, trying to figure out how to hide a 1.5 meter tall engine in a tank hull is bit tricky.

Yes, the L60 was a bit of a bellyflop. Though I don't think the basic concept of an opposed piston two stroke diesel per se is unworkable. Worked well enough e.g. in the Deltic or the Commer TS3.

Or if you want to play it safe, just do a four-stroke V-12 diesel like the Soviet V-2 tank engine. Or if you want a two stroke, the Detroit Diesel 71 series that was mentioned just a few days ago in another thread is a good example of a robust engine family doable with technology at the time.

For MTBs you need about 6 of them per boat, or more?
MTBs have different power requirement than aircraft engines which means the boat engines are de-rated. Their engines are rated at 1 hour (?) or 4 hours not 5 minutes or 15 minutes.

Sure, for a MTB you need either many engines, or bigger versions (e.g. the Deltic). I think from a duty cycle perspective marine engines are more similar to aero engines than automotive ones, in that they tend to be run an sustained high power for extended periods. But I guess you'd still want to derate them somewhat as weight isn't as critical and if you can improve reliability it's probably a decent tradeoff.

 

[wuzak]

Actually, force RR (gun point or Prison and Prison might not have convinced them) to give Napier the blueprints for the Buzzard. Go from there.

The Buzzard was, essentially, 6/5 of a Kestrel which was inspired by the Curtiss D-12.

It would give them experience with a more modern motor than the Lion, but you would still need an all new design for WW2.

 

[wuzak]

Buzzard --> Griffon I --> Griffon II is an interesting idea to avoid production conflict problems at the start of the war. Successful development of the engine could solve the problem of the Tornado/Typhoon and Firefly/Barracuda delays (maybe?). I do not know if getting the 2 companies to work together in a worthwhile manner would have been practical in the real timeline?

You missed a step - the 'R' between Buzzard and Griffon I.

The Griffon II is an all new design, that doesn't share anything from the previous generation Buzzard/R/Griffon I. Other than bore and stroke, of course.

 

[Shortround6]

So derate the initial version(s). For a British WWII tank 500 hp ought to be sufficient.

A 500hp diesel would have been wonderful for the Cromwell and Comet.
For the A-13 or Matilda or Valentine????? Or even the Churchill? That is a lot of years to sit on the Culverin.

Or if you want to play it safe, just do a four-stroke V-12 diesel like the Soviet V-2 tank engine. Or if you want a two stroke, the Detroit Diesel 71 series that was mentioned just a few days ago in another thread is a good example of a robust engine family doable with technology at the time.

Well, they stuck a lot of Detroit Diesel 6-71s into Valentines. They also stuck a crap load of them into landing craft. However at the time they were generally rated at around 165-180hp.
Some wound up in small railroad locomotives. They didn't show up in trucks until after WW II? Power did increase over the next 60 years

Sure, for a MTB you need either many engines, or bigger versions (e.g. the Deltic). I think from a duty cycle perspective marine engines are more similar to aero engines than automotive ones, in that they tend to be run an sustained high power for extended periods. But I guess you'd still want to derate them somewhat as weight isn't as critical and if you can improve reliability it's probably a decent tradeoff.

Actually in fast boats the duty cycle is worse. While automotive is operating at a lower percentage of power most of the time even aircraft in the late 30s (those that had variable pitch props anyway) were operating at 60-70% power in cruise, it varied a bit. Fast boats operate at greater % of power most of the time. Not full but they try to balance the weight/size/cost of the engine to it's expected speed range.

For the Deltic, a great design but you sticking 3 Jumo 205s in one power unit and if anything goes wrong?
It may have been too much of a risk in the late 30s or during WW II.

 

[tomo pauk]

A 500hp diesel would have been wonderful for the Cromwell and Comet.
For the A-13 or Matilda or Valentine????? Or even the Churchill? That is a lot of years to sit on the Culverin.

A 500 HP diesel would've been great in the Matilda and Churchill (provided the transmission is suited for the oomph).

 

[Shortround6]

The Cromwell was originally geared to do 40mph with the Meteor engine. They changed down to 32mph reduce wear and tear on the tracks and reduce injuries to the crew.

Turns out everything has to work together. Yes the Matilda and Churchill could have done with bit more power but you do have suitable steering gear, suitable suspension, and suitable track/running gear, for fast running.

 

[ThomasP]

You missed a step - the 'R' between Buzzard and Griffon I.

The Griffon II is an all new design, that doesn't share anything from the previous generation Buzzard/R/Griffon I. Other than bore and stroke, of course.

I know, but I do not know if the 'R' should be included in the ATL I used the identifiers of Griffon I and Griffon II as indicators of Napier development potential, not the specific RTL engines. Would RR have turned over the racing side of development in the ATL?

 

[wuzak]

I know, but I do not know if the 'R' should be included in the ATL I used the identifiers of Griffon I and Griffon II as indicators of Napier development potential, not the specific RTL engines. Would RR have turned over the racing side of development in the ATL?

Certainly not when they were racing it.

But that begs the question - the Griffon I was a detuned R, so would they give that away?

 

[ThomasP]

Good question. I was thinking that after the racing was over maybe the info would be transferred at the least, leading to a similar development path.

 

[Reluctant Poster]

A 500hp diesel would have been wonderful for the Cromwell and Comet.
For the A-13 or Matilda or Valentine????? Or even the Churchill? That is a lot of years to sit on the Culverin.

Well, they stuck a lot of Detroit Diesel 6-71s into Valentines. They also stuck a crap load of them into landing craft. However at the time they were generally rated at around 165-180hp.
Some wound up in small railroad locomotives. They didn't show up in trucks until after WW II? Power did increase over the next 60 years

Actually in fast boats the duty cycle is worse. While automotive is operating at a lower percentage of power most of the time even aircraft in the late 30s (those that had variable pitch props anyway) were operating at 60-70% power in cruise, it varied a bit. Fast boats operate at greater % of power most of the time. Not full but they try to balance the weight/size/cost of the engine to it's expected speed range.

For the Deltic, a great design but you sticking 3 Jumo 205s in one power unit and if anything goes wrong?
It may have been too much of a risk in the late 30s or during WW II.

GM was offering 3-71 and 4-71s in trucks in 1939 and 6-71s in buses in 1938

Truck History: 1939 GMC - First Year For The Legendary "Jimmy" Detroit Diesel - It's Still Being Built 85 Years Later - Curbside Classic

The classic Detroit Diesel has become not just legendary, but iconic. Thanks to its two-stroke design, it always sounds like its revving twice as fast as it really is, and […]

www.curbsideclassic.com

Also they put a crap load in Sherman's and M10s