The Ultimate WW2 Piston Engine

[Wuzak]

We have had discussions before on Radial vs In-line, air cooled vs liquid cooled, possibly even turbocharged vs supercharged.

My question is, if we were the design department of an engine manufacturer during WW2 what would we come up with for the ultimate aircraft piston engine in WW2?

What capacity?
Number of cylinders?
Liquid or Air cooled?
Poppet or sleeve valves?
Radial or in-line? Or other??
Turbocharged, Supercharged, or both? Turbocompound?

Bearing in mind that we would only have knowledge of what had passed before, and that we need to be in development early enough to actually get the engine into production and in service in quantity before the end of WW2.

The engine is to be used for both fighters and bombers.

[GregP]

I am a fan of both the radial and the inline.

Radial, Air cooled:
The best radial of WWII by far, in my opinion, was the R-2800, the R-3350 and Bristol Centaurus notwithstanding. Thus I would have experimented with a way to couple two R-2800s into one gearbox to drive an aircraft. If I were German, I would choose to do the same thing with the BMW radial.



Inline, liquid cooled:
I liked the Allison V-1710 the best, but I thought the V-3420 was flawed. Instead of two V-1710 engines next to each other, I think they could have made an X-24 with about an 80° included angle and had the exhausts exit toward each other btweeen the cylinders and merge into one pipe. Power level would have been about 3000 hp and there could have been left-hand, right-hand, and contra-rotating versions.

The contra-rotating version could have been mounted in the fuselage and could have been geared to the wings if there turned out to be any advantage to outboard props with very slim nacelles. Personally, I doubt the advantage of such a layout, but I have also read of high-speed problems when using concentrically-mountd contra-props, so I included that as an experiment.



Alternative:
As an alternative, I would have experimented with the Almen barrel engine with a thought to making one of sufficient power to be used in combat aircraft. I think it had great potential that was completely unrealized.

The bores and stokes of these engines would have been the same as the real items.

[Kutscha]

Greg, to make the 3420 an X engine the lower 'engine' would have to be re-designed ie oil scaveging. With the 'W' configuaration 1710 components did double duty.

The R-4360 used the same bore and stroke for its 4 row configuration.

The Griffon was never developed to it potential as was the Merlin.

The way to go would be sleeve valve engines.

[Wuzak]

BMW did try the twin engine geared thing and it didn't work too well. I think you would need the power takeoff to be between the engines for that to work. BMW had the rear engine driving is prop through a series of drop gears and driveshafts.

It also meant that the rear engine was the one driving the supercharger and consequently didn't have the power of the front engine!

Not sure why the V3420 failed - whether it was actually unsuccessful, or if it just wasn't given development time.

The Vulture was an X type engine developed from a V engine, as you have suggested for the V1710.

There were a few fuselage mounted engine/wing mounted props mooted. Including on of the original P-38 design proposals from Lockheed.

Sounds like you (Greg) ar elooking at a capcity of not less than 3400ci (56l) and up to 5600ci(92l)!!! I guess that is no different to using two conventional V1710s or R2800s.

The R2800 is quite a large engine, especially in frontal area. The Centaurus even more so. By combining twin engines behind each other you are effectively reducing the aircraft's frontal area. You could then opt to drive twin props as a coaxial unit, one front and one rear, or one on each wing via extension shafts and gears.

Cooling would be an issue with twinned air-cooled engines.


I agree with the Barrel engine. I did a rough layout on CAD at work the other day (work's slow at the moment, OK) and a B2800 (Barrel engine of 2800ci capacity) looks like it will be of a similar length to the R2800, perhaps a little longer, but about 2/3 the diameter. It would be similar in frontal area to a Merlin, but with an extra 19l of capacity, and substantially shorter.

Valve actuation has always been a problem for wobble plate motors, but using sleeve valves would solve most, if not all, of those issues.

The "down side" of the B2800 compared with the R2800 is that it would have to be liquid cooled.

[Wuzak]

quote:Originally posted by GregP

Alternative:
As an alternative, I would have experimented with the Almen barrel engine with a thought to making one of sufficient power to be used in combat aircraft. I think it had great potential that was completely unrealized.


The Almen had 425hp (317kW) and weighed 749lbs (340kg). In the mid '20s.

The Liberty L12, of only slightly earlier vintage, had 449hp (335kW) and weighed 845lbs (384kg).

The Pratt & Whitney R1340 came a few years later, and had 550 hp (410 kW) weighing 928lbs (422kg). It also had a diameter of over 1.3m - looking at the Almen I'd say that is at least twice the diameter (and therefore at least 4 times the frontal area).

So basically the Almen had a pretty decent performance for its day. It wasn't supercharged either.

[GregP]

Hi Kutscha,

I realize the oil scavenging would have to be redone, but there are numerous inverted Vee engies, so it can't be all that tough to do.

It is quite possible the engine would have been a very good one, though there is an equal possibility it would have been a dud.

Anyone who says he or she could have designed a "world beater" is placing themselves in rarified company since the people who DID design "world beaters" were using the best knowledge available at the time coupled with the best technology avilable.

I merely sought to make the very good into something better by coupling the powerplants or by inserting more of the same cylinders onto a new, larger case.

Another thing we would have neede was better propeller design to go with the power increase ... but that's another story.

[Red Admiral]

quote:What capacity?
Number of cylinders?
Liquid or Air cooled?
Poppet or sleeve valves?
Radial or in-line? Or other??
Turbocharged, Supercharged, or both? Turbocompound?

Lets go with Italy. I have experience with large and powerful engines, the Isotta-Fraschini Asso types. The largest is 57L and produces 1800hp continuous in 1931ish. The next down is 47L and produces up to 940hp. Both are reliable, being used for MAS and on numerous long-distance flights. Both have the same exterior dimensions. Weights are about 663kg/800kg. With the Schneider trophy I have experience with the Fiat AS.5 a 25L motor producing 1500hp, but thats about as far as it can be developed. (60hp/L) at the time. Experience with the AS.6 shows the value of contra-props.

Basically I want something that'll eventually produce 4000hp+. The Merlin and L121 are producing about 40hp/L in the late 30s. I've already shown that I can boost engines up to 60hp/L eventually, presumably with time they'll be able to run more reliably at this. I combine both the AS.6 and Isotta-Fraschini engines groups and start producing a small engine of around 23L with a view to bolting two together.

Engine configuration. The W is out for frontal area. Vee type looks arractive with the L121 and AS.5 using this. However this does limit the revs a bit. So I'll adopt a flat layout that can eventually run to 4000rpm+ Number of cylinders, theres no advantage to be had with a view to smooth running after 8-cylinders with a flat engine and I want to keep the length down. So a flat-8 it is. I don't have the option of sleeve valves, so poppet valves it is.

The engine mounting itself, we'll mount engine no.1 backwards and engine no.2 forwards both running into a gearbox. The no.1 shafts rotates freely around the outside with the no.2 shaft rotating oppositely on the inside. This drives your contra-prop (which you already know to be about 10-15% more efficient than a conventional one). I'd imagine two bladed to start with, then 3 blades 1941ish. Quite short blades at around 2.5m I think.

Got to go with supercharging really, as I don't have an option to develop turbochargers. Even if I did, I wouldn't because of the thrust loss, especially at higher altitudes. I remember from the mid 1920s when Giudoni developed a turbocompound diesel. I look at the idea and set one team to work on it. That'll be more suitable for bomber engines. The problem now is where to put the supercharger(s). The AS.6 has 1 small supercharger on engine no.2 which boosts to 1.75bar (c.180000ft) I could make this larger to get up to 2bar or so, but this again adds length to the engine. I seriously look at horizontally mounted superchargers underneath the engines, one for each.

What is the result, an engine producing c. 1800hp in 1939 at 3000rpm, rising to 2800hp by 1943ish, and by 1945-46, about 3500-4000hp at 4000rpm. The engine is inherently reliable, because there are two of them, not linked but completely separate. The only thing I worry about is the wider fuselage needed for the flat layout, but I think its worth the sacrifice.

[Wuzak]

With twin flat 8s separated by a gearbox will the engine become too long?

Might it be prudent to sit them one on top of the other, both driving through the gearbox at the front.

Will this cause the frontal area to be too large?

[Red Admiral]

quote: With twin flat 8s separated by a gearbox will the engine become too long?

Might it be prudent to sit them one on top of the other, both driving through the gearbox at the front.

It might possibly be too long compared to normal engines, but maybe only a foot or so. Lengthening the fuselage to keep it stable won't be too hard. I considered having one on top of the other like the Fairey Prince/Monarch, but the frontal area is massive, and its just so big. Have a look at the Battle-Prince testbed. Having the engines inline with each other brings the CoG back a bit and saves some complexity - and its already been done.

[montanamotor]

Aaaah,

THAT's my thread! Give me some time to consider thoroughly. 'll report back ASAP. Some short notices in advcance:

1. Sleeve-valves for aircooled radials. The Centaurus is a real high-scorer!

2. Rotary-disc-valves for liquid-cooled inliners.

3. Why not mount three single cylinderbanks of an Allison or RR Griffon at 120 degrees to one another working on one crankshaft, thus resulting in an 18 cylinder, 3-per-row, 6-row-"radial"...?

3. The Almen barrel-engine really is HOT! I'd give it rotary-valves, too. This would reduce the LENGTH, as well as the WHEIGHT of the barrel about 1/3 each, compared to a poppet-valve-design.

Today, pure turbosupercharging is state of the art. Yet, back in the 1940ies, a compound was considered optimum: A mechanical supercharger was used to achieve rated power output at sealevel in ANY turbosupercharged engine of that era. Yet, this was combined with an additional turbosupercharger to maintain power at higher altitude/compensate for lower air-density.

Further details later this weekend. Got to go shopping now for good...:D

Cheers!

Montanamotor

[Wuzak]

quote:Originally posted by montanamotor

3. The Almen barrel-engine really is HOT! I'd give it rotary-valves, too. This would reduce the LENGTH, as well as the WHEIGHT of the barrel about 1/3 each, compared to a poppet-valve-design.


Disc valves? If you meant rotary valves they would be similar to a conventional camshaft, and difficult to implement on the barrel engine. Disc valves, on the other hand, could be activated directly through a gear train off the crank.

I think sleeve valves would make the engine slightly larger in diameter, but that aspect of the design is well under control. It will reduce the overall length of the engine substantially, and arguably reduce the engine's complexity.

quote:Originally posted by montanamotor

3. Why not mount three single cylinderbanks of an Allison or RR Griffon at 120 degrees to one another working on one crankshaft, thus resulting in an 18 cylinder, 3-per-row, 6-row-"radial"...?


The problem with this layout is the ehxaust from the central bank. Napier built the Lion in this layout, then started producing the H layout ending with the Sabre.

[Wuzak]

quote:Originally posted by Red Admiral

quote: With twin flat 8s separated by a gearbox will the engine become too long?

Might it be prudent to sit them one on top of the other, both driving through the gearbox at the front.

It might possibly be too long compared to normal engines, but maybe only a foot or so. Lengthening the fuselage to keep it stable won't be too hard. I considered having one on top of the other like the Fairey Prince/Monarch, but the frontal area is massive, and its just so big. Have a look at the Battle-Prince testbed. Having the engines inline with each other brings the CoG back a bit and saves some complexity - and its already been done.


The Fairey Prince Monarch/Prince were, as I understand it, twin V12 engines - quite tall engines, and wide when paired together.

With the flat layout you won't be adding to the width, and the height would still be below that of a normal in-line engine. If you geared the cranks together you could get them even closer together, but since that adds complexity and other issues I am sure you would avoid it.

Also, note that the Allison V3420 was still lower in frontal area than a big radial such as the R2800 or Centaurus.

[montanamotor]

Errr, hmmm,

Wuzak, you wrote - quote:

"I think sleeve valves would make the engine slightly larger in diameter, but that aspect of the design is well under control. It will reduce the overall length of the engine substantially, and arguably reduce the engine's complexity."

Unquote.

Errr - Wuzak, please see THIS:

http://i111.photobucket.com/albums/n149/montanamotor/Barracuda%20pics/bild12.gif

Gear-train for sleeve-valve-drive of the Bristol Hercules-engine

If there is one thing on earth, a sleeve-valve-design CAN NOT offer, it's reduced complexity...;)

Not to mention the arrangement of small cranks (one per cylinder) inside the case, one of each setting the sleeve-valve per each cylinder into it's "wobbling" motion...

And don't forget: You still had to add yet over a dozen more 90 degree-bevel-drives - one per each cylinder - to alter the rotation from the radial application like in a radial engine, into an axial array, like you would need in a barrel-engine.

For disc valves, on the other hand, there would be ONE SINGLE bevel-drive needed only. The discs being teethed at the outside perimeter would be meshing with each other, this way driving each other: One disc would drive the next one. That would be it...

Cheers!

Montanamotor

[Wuzak]

I think that the motion required could be more easily achieved in an axial engine system than a radial engine.

But maybe you are right, it would still be more difficult than a disc valve system.

Mind you, I dare say that they had more success with sleeve valves than disc valves by the early '40s.

[Groggy]

quote:Originally posted by Wuzak

I think that the motion required could be more easily achieved in an axial engine system than a radial engine.

But maybe you are right, it would still be more difficult than a disc valve system.

Mind you, I dare say that they had more success with sleeve valves than disc valves by the early '40s.


Hi,
Complex maybe, the Centaurus for example was even more complex but with 3000hours between major overhauls must have been reliable and it gave the Tempest a 420mph cruising speed. The proposed Merlin 54- H-24 would have had a frontal area of only 16.5 sqft when attached to a 55inch diameter bulkhead similar diameter to the Centaurus but 50% more power.
The Monarch was two flat vertically opposed 12 cylinder engines
Driving contra-rotating airscrews with similar dimensions to the R-R 54-H24 that it inspired. The 18 cylinder Griffon, Napier Lion look alike is a very interesting proposition. But an X 24 configuration might be better for power output and frontal area considerations?
The Pennine is a sleeve-valve X -24 and no other realistic engine could match it for low frontal area, the engine could fit in a 46inch sided square box

[Wuzak]

quote:Originally posted by GroggyThe Pennine is a sleeve-valve X -24 and no other realistic engine could match it for low frontal area, the engine could fit in a 46inch sided square box


46" = 1168mm

This guide to WW2 engines http://www.ww2guide.com/engines.shtml has the Napier Sabre at 1016mm wide by 1168 high.

The V1710 is listed as 744mm x 932mm. The V3420 is wider at 1421mm but shallower at 863mm. This is an area of 1.23m² compared with the listed dimensions of the Penine at 1.37m². The V1710 is 0.69m² and the Sbare is 1.19m² frontal area.

I imagine the Merlin would be similar in dimensions to the V1710.

So, if the Pennine was that size it wasn't especially of a low frontal area.

The Crecy would make an interesting case... 2 stroke with sleeve valves, should make for a reasonably compact motor, particularly in frontal area. and it was very powerful for its cubic capacity, having less capacity than the Merlin but (much) more power.

[montanamotor]

Best Engine award:

a. Radials

Bristol Centaurus 53.6 L, direct-fuel-injected, fan-cooled, turbo-supercharged ONLY (mechanical charger omitted), Intercooler, ADI.

Power estimate: 3700 HP @ 2700 rpm @ 25,000 ft


b. Inliners

Daimler Benz DB 603 44.5 L, direct-fuel-injected, pressure-cooled, turbo-supercharged ONLY (mechanical charger omitted), Intercooler, ADI.

Power estimate: 3650 HP @ 3000 rpm @ 25,000 ft

Power estimates valid for then-generally-availlable 135/150 grade fuel. With exotic fuel mixtures, there would be more to come. As maximum revs are mechanically limited due to stroke/mean piston speed to said figures, power-output remains a function of max. BMEP/torque only. BUT: These engines are NOT supertuned. I was considering power-outputs in terms of usability for classic military service.

These engines represent the maximum of what may have been achievable for use in single-engined fighters, based on techniques which were availlable in 1944/1945.

For bombers, any multiple of the abovementioned would have been possible, of course.

Counter-rotating props? Yes, please!

Cheers! :D

Montanamotor

[Wuzak]

quote:Originally posted by montanamotor

Daimler Benz DB 603 44.5 L, direct-fuel-injected, pressure-cooled, turbo-supercharged ONLY (mechanical charger omitted), Intercooler, ADI.

Power estimate: 3650 HP @ 3000 rpm @ 25,000 ft


You sure about the hp for that engine?

http://en.wikipedia.org/wiki/Daimler-Benz_DB_603

A turbocharger compared with a supercharger shouldn't make all that much difference....

In any case, I would think that the Sabre was the ultimate actual piston engine (liquid cooled) of WW2.

[Groggy]

quote:Originally posted by Wuzak

quote:Originally posted by montanamotor

Daimler Benz DB 603 44.5 L, direct-fuel-injected, pressure-cooled, turbo-supercharged ONLY (mechanical charger omitted), Intercooler, ADI.

Power estimate: 3650 HP @ 3000 rpm @ 25,000 ft


You sure about the hp for that engine?

http://en.wikipedia.org/wiki/Daimler-Benz_DB_603

A turbocharger compared with a supercharger shouldn't make all that much difference....

In any case, I would think that the Sabre was the ultimate actual piston engine (liquid cooled) of WW2.


Hi Wuzak,

Many thanks, you are right, I was surprised at the Napier Sabre’s low frontal area but should not have been because that was one of its main design criteria. Agreed the Sabre was an outstanding engine and the improvements in reliability were such that they had a surplus of about 3000? brand new engines by the end of the war that were otherwise thought would be needed as spares but were not.
What I should have posted was power output per square foot of frontal area but on reflection of the engines in service the Sabre must have it.

The tricky part for your original question is either to go with a liquid cooled sleeve valve fast revving small cylinder size and inline configuration or with Fedden and the Orion, air cooled with sleeve valves and super large cylinders?.
Can we consider a two-stroke as an alternative to the four stroke?

[montanamotor]

Hi, Groggy.

Please note, that I put emphasis on OMITTING the basical mechanical supercharger. For good reason: A mechanical charger at full song drains over 20 percent from the engine's gross power output to spin.

But as soon as you replace the mechanical charger with a solely turbosupercharged one, you REGAIN these over 20 percent to additionally drive the prop-shaft at the other end of the engine.

Back in 1940/45, turbosuperchargers were commonly ONLY used to compensate for loss of power at altitude / reduced air density. Without reason. Back then, it was a HABIT, to bring an aircraft-engine to power first with a mechanical charger, ant then add yet another turbosupercharger to compensate for the altitude: "We do it, 'cause we always did it that way!" - you know.

But today's actual turbosupercharged aircraft-engines do all, without exception, exclusively rely on torbosupercharging ONLY - and they do very well in doing so.

In the early days of single carburettors, the compressor-wheel of the mechanical charger often had to double-serve as a "mixer", too - litterally, to enforce an even fuel mixture being distributed to the separate cylinders. But with direct fuel injection, this additional function becomes obsolete, too.

Also - omitting the mechanical supercharger from an engine, solves a million and one problems, as well: Much less complexity, wheight, cost, etc. etc.

Sometimes, it takes a decade or two, until people stop making nonsense, ya' know...

In the end, I wasn't summing up what WAS done to the engines, but what COULD HAVE BEEN DONE to them, had time and money been there to be spent on those engines I mentioned.

You are right, of course: The Napier Sabre is one GREAT engine, and I like it very much. But the complexity of it really makes me shiver... I have a perspex-drawing of this Napier Sabre, copyright Aeroplane Monthly, somewhere in my books. When you look at this drawing, you really get a good idea of what the word "complexity" REALLY means...

Have you never wondered, why there wasn't ANY attempt made to use the Napier Sabre in commercial aircraft, once the War was over? That's why: It was SO complex, nobody in the world could afford the maintenance neccessary to keep it going in an airliner.

Cheers!

Montanamotor

[Groggy]

quote:Originally posted by montanamotor

Hi, Groggy.

Please note, that I put emphasis on OMITTING the basical mechanical supercharger. For good reason: A mechanical charger at full song drains over 20 percent from the engine's gross power output to spin.

But as soon as you replace the mechanical charger with a solely turbosupercharged one, you REGAIN these over 20 percent to additionally drive the prop-shaft at the other end of the engine.

Back in 1940/45, turbosuperchargers were commonly ONLY used to compensate for loss of power at altitude / reduced air density. Without reason. Back then, it was a HABIT, to bring an aircraft-engine to power first with a mechanical charger, ant then add yet another turbosupercharger to compensate for the altitude: "We do it, 'cause we always did it that way!" - you know.

But today's actual turbosupercharged aircraft-engines do all, without exception, exclusively rely on torbosupercharging ONLY - and they do very well in doing so.

In the early days of single carburettors, the compressor-wheel of the mechanical charger often had to double-serve as a "mixer", too - litterally, to enforce an even fuel mixture being distributed to the separate cylinders. But with direct fuel injection, this additional function becomes obsolete, too.

Also - omitting the mechanical supercharger from an engine, solves a million and one problems, as well: Much less complexity, wheight, cost, etc. etc.

Sometimes, it takes a decade or two, until people stop making nonsense, ya' know...

In the end, I wasn't summing up what WAS done to the engines, but what COULD HAVE BEEN DONE to them, had time and money been there to be spent on those engines I mentioned.

You are right, of course: The Napier Sabre is one GREAT engine, and I like it very much. But the complexity of it really makes me shiver... I have a perspex-drawing of this Napier Sabre, copyright Aeroplane Monthly, somewhere in my books. When you look at this drawing, you really get a good idea of what the word "complexity" REALLY means...

Have you never wondered, why there wasn't ANY attempt made to use the Napier Sabre in commercial aircraft, once the War was over? That's why: It was SO complex, nobody in the world could afford the maintenance neccessary to keep it going in an airliner.

Cheers!

Montanamotor



Hi Montanamotor,
I agree about what you are saying about the Sabre’s complexity and it being less than ideal as a civil engine, but for an ideal military inline engine your suggestion of 18 –inverted Y configuration needs, deserves some serious thought especially for a conventional single engine fighter. The use of DB blocks and fuel injection would give it the edge over both the Griffon and Alison..

I am puzzled by a R-R wartime report that stated the advantage swung again to the mechanically driven supercharger at extreme altitude after passing through an altitude band were the turbo charger had the advantage.

I follow the logic of your argument about charging the engine but we are talking about aircraft engines. An important factor is that at high speed , high altitude; exhaust energy becomes more useful than converting it to drive the airscrew otherwise at lower speeds and altitudes the reverse happens and the engine should be super fuel efficient as in the case of the Nomad .

This Jet exhaust thrust effect becomes a very significant effect and must be providing more that half the thrust available in those extreme conditions. So as to operate at the highest speed possible the inline inverted Y or a X configuration has some advantages.
I am running out of time but will continue at latter date

[Wuzak]

Turbocharging isn't "free" energy. Having the turbine in the exhaust has a detrimental effect on the exhaust leaving the cylinder.

I do remember reading somewhere that overall a supercharger is more efficient than turbocharging. This was a few years ago, and applied to car engines. I don't know how it applied in 1939-1945.

[montanamotor]

Groggy,

Rolls Royce was always good in promoting things they were good in...

Remember that, turbosupercharger-development during the war among allies was completely an AMERICAN endevour, whereas Roll-Ryce admittedly excelled in the development of mechanical superchargers. I find it totally natural, that, unter those circumstances, RR would lay some "bias" on mechanical superchargers, rather than on turbosuperchargers.

Did you know that, Rolls-Royce in the early 1960ies waved the development of a jet-engine with a high-bypass-ratio - FAN-JETS - as too complex, too little to gain from? It was GENERAL ELECTRIC which had to develop the modern jet-airliner-engine to strength. Only later, RR entered the FAN-scene, after they reluctantly admitted, GE had done a great job on what they before had called a complete waste of time...

BTW: One must remember that, in the end, the SUM of energy being availlable to drive your plane, will always remain more or less the same - supposed, the engines compared will produce power at a comparable rate of effichiency. If you convert the chemical energy contained in a certain amount of fuel into thrust via a prop and using a turbosupercharger, hence without a mechanical charger which would otherwise consume about 25 percent of power by power-loss in the gear-train and by spinning the charger-wheel, or if you'd add the residual thrust from the exhaust stacks to the power-sources total thrust, which you before in some way had diverted to drive the mechanical charger(s) first, and finally recovered it by blowing the exhaust-gases rearward to augment total thrust, is more or less a question of choice and, exellence in the respective area.

But, yeah, a 24 cylinder horizontal-H-shaped opposed-piston-engine might well be the choice of the day, too. But, if it was after me, I'd take a purely turbosupercharged-one, still...

Cheers!:D

Montanamotor

[montanamotor]

Wuzak, this is pure claim. Of course, You'll have to design an engine specifically to fully use turbocharging to your benefit. But in the end, simplicity and power-gain of a turbosupercharger-installation will by far exceed any detrimental effects on scavenging the cylinders.

Example? In the mid-80ies, turbosupercharged Formula-1-cars were delivering OVER 1000 HP from 1,4 liters of displacement, and this was done by showing specific-fuel-consupmption-figures, which are STILL unparalleled by any naturally aspired engine to-day.

Believe me: If it was for a more-or-less constant power-setting as normally used in aircraft, turbosupercharging is definitely the name of the game. This has ben established in the engineering world for decades, now.

Cheers.

Montanamotor

[Groggy]

Montanamotor

Rolls Royce was always good in promoting things they were good in...
True!
But also true of most companies.

Remember that, turbo-supercharger-development during the war among allies was completely an AMERICAN endeavour, whereas Roll-Royce admittedly excelled in the development of mechanical superchargers.
True …agreed

I find it totally natural, that, under those circumstances, RR would lay some "bias" on mechanical superchargers, rather than on turbo-superchargers.

Not what I was saying, They actually implied or say in the report that the turbocharger was superior at high altitude, (from memory up to about the combat ceiling of a B17.) but then the advantage turned back to the mechanically driven, this was in the context of high speed flight with engines suitable for a fighter.

Did you know that, Rolls-Royce in the early 1960ies waved the development of a jet-engine with a high-bypass-ratio - FAN-JETS - as too complex, too little to gain from? It was GENERAL ELECTRIC which had to develop the modern jet-airliner-engine to strength. Only later, RR entered the FAN-scene, after they reluctantly admitted, GE had done a great job on what they before had called a complete waste of time...

Far more complex pressures at work, Rolls Royce lost the plot at times however politics was muddying the waters. The British Aerospace Industry was by that being used as a pawn to be sacrificed in the European scene by the Foreign Office to gain Britain’s admission to the Market.



BTW: One must remember that, in the end, the SUM of energy being available to drive your plane, will always remain more or less the same - supposed, the engines compared will produce power at a comparable rate of efficiency. If you convert the chemical energy contained in a certain amount of fuel into thrust via a prop and using a turbosupercharger, hence without a mechanical charger which would otherwise consume about 25 percent of power by power-loss in the gear-train and by spinning the charger-wheel, or if you'd add the residual thrust from the exhaust stacks to the power-sources total thrust, which you before in some way had diverted to drive the mechanical charger(s) first, and finally recovered it by blowing the exhaust-gases rearward to augment total thrust, is more or less a question of choice and, exellence in the respective area.

Yes

But, yeah, a 24 cylinder horizontal-H-shaped opposed-piston-engine might well be the choice of the day, too. But, if it was after me, I'd take a purely turbosupercharged-one, still...

At speeds less than 400mph I would agree, but I do not know for certain in all cases, The propeller/ airscrew looses efficiency as one approaches Mach one. This was not a problem with Formula one cars, incidentally R-R Black Museum has an example of a F1 engine on display near by the big W24 Alison.
I read something similar to what Wuzak read about mechanical and turbo driven chargers so will consult a former Armstrong/Bristol/R-R person on the subject.but agee about the F1 engine
Sorry again time is short.

[Red Admiral]

Groggy - do you have any information on the Orion? I've never heard of it before.

At higher altitudes and speeds, supercharging is more effective than turbocharging. The exhaust is providing about 20% thrust that would otherwise go into the turbocharger. At higher altitudes and speeds, the extra thrust is worth more than the power loss in the mechanical supercharger.

[montanamotor]

One quote from Kutscha, in the P 51-engine-thread:

Quote:

" The V-1650-9 only put out 1630bhp at 23,000ft, wet, high blower. At 10,100ft it was 1930bhp, wet, low blower."

Unquote.

Did you ever ask yourself, WHY the Merlin delivered 300 HP LESS at 23,000ft, than it did at 10,100ft??

BECAUSE THE SECOND-STAGE OF THE MECHANICAL CHARGER HAS CUT IN AND USES UP THE BALANCE FOR SPINNING!

Each stage in a Merlin requires roughly 300 HP to spin the respective blower. with TWO stages engaged, at 23,000ft the two blowers absorb roughly 600 HP of the Merlin's total output.

With ejector-exhaust-stacks you can RECOVER some of the lost power-to-prop as pure thrust. But by doing so, the engine in no way produces MORE thrust than an engine with a turbosupercharger. It only spends HP here at the compressors, to regain pounds-of-thrust there at the stacks.

A turbosupercharger-equipped engine for shure doesn't show a "thrust-recovery" like a mechanically charged engine does. But, on the other hand, it also doesn't use up to 1/3 of it's power produced to spin a charger, but leaves this to the energy in the exhaust-gases, and delivers all his power to the prop, instead.

In german, we call this a "Nullsummenspiel": You may add up the different factors any way you like - in the end, the result will always be the same (...altitude-performance, in this case).

I can accept the argument with props being less efficient at speeds over 400 knots, though.

Here comes a point, where you might start considering a two-stage-Merlin at altitude rather working as a piston-compound-jet-engine (by it's exhaust-stacks) with a piston-driven blower (compressors), and the additional prop transforming surplus engine-power into residual piston-generated thrust, only.

One might even drive this idea so far as to completely dispense with the prop (or maybe reduce it to a pure fan for cooling the radiators, only), while ALL of the power you need for driving the plane would be coming from the immense exhaust stacks, instead! Weird... [:0]

I think, I just invented the piston-pulsojet-engine. Makes you think, doesn't it...? :D

Cheers!

Montanamotor

[Wuzak]

quote:Originally posted by montanamotor

Wuzak, this is pure claim. Of course, You'll have to design an engine specifically to fully use turbocharging to your benefit. But in the end, simplicity and power-gain of a turbosupercharger-installation will by far exceed any detrimental effects on scavenging the cylinders.


I think we'd agree that some turbocharger installations were less than simple. Take the P-47's installation, for example. It took up a lot of space and added a lot of weight.



quote:Originally posted by montanamotor

Example? In the mid-80ies, turbosupercharged Formula-1-cars were delivering OVER 1000 HP from 1,4 liters of displacement, and this was done by showing specific-fuel-consupmption-figures, which are STILL unparalleled by any naturally aspired engine to-day.


In the mid '80s F1 engines could produce up to 1400hp under special circumstances. That is to say in qualifying, with no expectation that the engine would last more than a few minutes. In race trim the engines were around 1000hp, but......

When this was happening they were using special fuels, more potent than the average petrol or avgas. More hazardous as well. These fuels allowed them to use astonishing boost pressures. When fuel limits were introduced - type and amount available for a race - the power came down to a lower level, about 900hp, which is about the same as the 3l V10s have had for the past 4 or 5 years.

In terms of specific fuel consumption, I'm not so sure about that. In terms of specific power (hp/l) they were definitely the best in the history of circuit racing cars.

[Wuzak]

In the general automotive industry the technology with turbochargers has advanced very significantly in the last 20 years. Turbos have become more efficient and effective, yet several companies have turned to superchargers instead.

[GregP]

Hi Wuzak,

Now we got to a subject that I VERY familiar with ...

If you want power and efficiency, the turbocharger is the way to go in an automobile. Turbos make more power at the expense of a bit of "turbo lag" in the throttle response.

Most turbochargers of the automotive variety use engine oil for lubrication, and engine oil has a few metal bits in it sometimes. Unfortunately, they also spin at high RPM, some reaching over 80,000 RPM. If a driver runs a turbo car hard and then stops and shuts it off with no spin-down time, you have a turbo spinning down with no oil pressure and it affects the life of the bearings to a significant degree.

Most superchargers for automotive use spin at less than 20,000 RPM and are coupled to the crankshaft. So, when the engine stops, the supercharger stops, too.

From the consumer's standpoint, assuming a performance-oriented driver, a turbo with an spin-down electronic shutoff is best for performance.

From a manufacturer's standpoint, taking into consideration the warranty, the supercharger offers the least maintenance expense and the lesser of the two as far as incurred warranty charges are concerned.

The short version is that car companies prefer superchargers due to lower overall costs and performance nuts prefer turbocharging for better overall power, though the supercharger IS more linear in its delivery than the "peaky" turbos.

I have owned both. For equivalent power output, there is little to choose. For ultimate power production, a turbo is better. For driveability, the supercharger is better, but you have boost ALL THE TIME. In a turbo car, you CAN cruise at low RPM with little to no boost, significantly erxtending the life of the otherwise high-power engine.

By way of example, suppose I turbocharge my 2002 Camaro SS. It now has about 380 HP at the crank. A turbo kit with no other changes can easily take that to 450 hp or more, but I could cruise at 65 - 75 mph off boost and cruise at essentially the same power as I am now. The extra turbo power only hits when I go over the threshold of the waste gate powerband.

If I supercharge it, I would have boost ALL THE TIME, and would be cruising at significantly higher power levels than I am now, burning more fuel.

So ... you have a tradeoff.

In aircraft use, a turbocharger is probably ALWAYS better, at least with today's technology. I'm not too sure about the technology of WWII since I wasn't there to see how it worked, but the technology of today relies heavily on computers ... which weren't available in 1938. I have flown in several WWII-era aircraft, but none that were turbocharged. Superchargers were and ARE mechnical, and they worked fine at the time as well as today, but they DO consume crankshaft power as noted above in many posts.

Personally, I think a good turbocharger on a Merlin would be a GREAT thing, but the population of Merlins is small and shrinking all the time, so a development would be a labor of love as opposed to an opportunity for profit.

[Red Admiral]

quote:If you want power and efficiency, the turbocharger is the way to go in an automobile. Turbos make more power at the expense of a bit of "turbo lag" in the throttle response.


More recent developments eliminate this somewhat. All the fuel injected into the engine is not burnt, there is still some present most of the time. The trick to eliminate lag is either 2 turbos, or 1 that spins all the time. BMW uses 2 turbos, one small with hardly any lag that basically acts to add power at low rpm before the larger turbo can be powered up. The other way, which isn't much used, most notably by a small company called ProDrive (they are coming to F1 in 2008 and operate DB series racing cars). Essentially the waste fuel is burnt outside the cylinder and is used to keep the turbo spinning over.

[Groggy]

quote:Originally posted by Red Admiral

Groggy - do you have any information on the Orion? I've never heard of it before.

At higher altitudes and speeds, supercharging is more effective than turbocharging. The exhaust is providing about 20% thrust that would otherwise go into the turbocharger. At higher altitudes and speeds, the extra thrust is worth more than the power loss in the mechanical supercharger.

Hi Red Admiral,

I do not have details with me, but from memory, the Orion was Fedden’s last engine for Bristol Engine Company before being sacked. It was rather like a large eighteen-cylinder Centaurus. The capacity of the engine increased to over 100 litres from just over 50litres, not sure of the exact number of cylinders or exact capacity. They must have been expecting in excess of 4000hp. perhaps 5000hp. The overall dimensions were not that much larger than the Centaurus.
The name was eventually used by Bristols for a super advanced turbo-prop that in turn was cancelled for political reasons, circa 1958/9.

[Nick Sumner]

quote:Originally posted by Red Admiral

Groggy - do you have any information on the Orion? I've never heard of it before.

At higher altitudes and speeds, supercharging is more effective than turbocharging. The exhaust is providing about 20% thrust that would otherwise go into the turbocharger. At higher altitudes and speeds, the extra thrust is worth more than the power loss in the mechanical supercharger.


Not to butt in but there is some info about the Orion in 'Fedden - The Life of Sir Roy Fedden' by Bill Gunston published by the Rolls Royce Heritage Trust pages 244 - 248 has information, diagrams and comparative drawings of both the Orion and a 4 row 28 cylinder 5 3/4 in bore by 7 in stroke (ie a double Centaurus) engine.

[montanamotor]

Nick,

did the Orion have a corncob-shape, or were the cylinders to be arranged in seven straight lines - one behind the other - à 4 cylinders?

A picture or a link would be great to see it with own eyes.

Cheers!

Montanamotor

[Nick Sumner]

Hi Montanamotor, the Orion was basically a bigger Centaurus, ie 18 cylinders in two rows of nine, 6 1/4 in bore and 7 1/2 in stroke.

The unnamed 28 cylinder 'Double Centaurus' does not appear to be a 'corncob' design from the diagram, it looks similar to the BMW 803 layout - ie row 3 is directly behind row 1 and row 4 is directly behind row 2. However, although it has Centaurus bore and stroke, 28 cylinders means 4 rows of 7 rather than 4 rows of nine so there is more room for the air to circulate. It is also noticable that the cowling outline is well clear of the cylinder heads - again giving more circulation room - whereas Hercules, Centaurus and Orion were (or were to be) very closely cowled.

I'll scan the drawings and post them a bit later today.

[montanamotor]

Cool. [8D]

I'll stand-by to see that. Yes, I admit - I AM an engine-maniac...

Cheers!

Montanamotor

[Nick Sumner]

Here as promised are (I hope) links to the drawings of the Orion, 28 cylinder engine and a couple of other interesting tidbits from 'Fedden - The Life of Sir Roy Fedden' by Bill Gunston. A fascinating book.

I appologise for the large file sizes but there is alot of detail and some tiny printing I thought might be useful.

http://i115.photobucket.com/albums/n291/nsumner/PP246top.jpg

http://i115.photobucket.com/albums/n291/nsumner/PP246lower.jpg

http://i115.photobucket.com/albums/n291/nsumner/PP247top.jpg

http://i115.photobucket.com/albums/n291/nsumner/PP247lower.jpg

http://i115.photobucket.com/albums/n291/nsumner/PP255.jpg

[montanamotor]

Hi, Nick,

I have received the links on the "Supercentaurus" and have learned them by heart, already.:D

Question: May I ask you to send the drawings as PDF-files to my personal email-address, at as high a resolution as possible...?

PLEEEEEEASE!

montanamotor(leave this out)@web.de

I would like to add them to my little "collection".

Thanks in advance!

Cheers!

Montanamotor

[Trexx]

WTF?

[Wuzak]

Hey guys, I have been trying to draw a barrel engine in 3d, and I have finally found how it all works (in Almen engine style - there are other ways which can be used, but I wanted to use the Almen engine as a basis).

I have drawn a very basic engine at the moment, which works, but has no valves or such. The Almen engine had an odd and very inefficient valve arrangement, but which helped to keep the engine short.

I figure that a barrel engine could relatively easily be made using the barrels of an R2800, or similar. I think activating the pushrods for the valves would be relatively simple in a barrel type engine, much more so than OHC types.

Anybody have drawings of R2800 cylinder barrels, pistons and heads, or know of where to find them?

[GregP]

Hi Wuzak,

Send me your email and I'll send you some pdf's.

[Wuzak]

quote:Originally posted by GregP

Hi Wuzak,

Send me your email and I'll send you some pdf's.


Greg, just checking to see if you received my e-mail.

[Double T]

I came across some interesting background on the Pratt & Whitney R-2800 C-Series radial engine that powered the P-47M-1-RE Thunderbolt:

--from Cradle of Aviation.org

"During durability testing of the C series R-2800 by Republic, it was decided to find out at what manifold pressure and carburetor temperature caused detonation. The technicians at Republic ran the engine at extreme boost pressures that produced 3,600 hp! But wait, it gets even more amazing. They ran it at 3,600 hp for 250 hours, without any failure! This was with common 100 octane avgas. No special fuels were used. Granted, the engines were largely used up, but survived without a single component failure. Try this with Rolls Royce Merlin or Allison V-1710 and see what happens."

The Republic P-47M-1-RE was reputed to be the true "Hot-Rod" of the Thunderbolts. Able to easily intercept V-1s, and even the Me262 in a shallow-dive.
--------------------------------------------
Tim

[Trexx]

Zoom-zoom! [8D]

[Wuzak]

Bear in mind that 3600hp for the R2800 is equivalent to less than 2200hp for the Merlin or Allison V1710. And some marks of both did achieve that sort of hp in experimental versions late in the war/post WW2.

I dare say the the reason a flogged out R2800 was able to do this was that when the engine was running at full power the expansion of its parts brought it close to teh ideal clearences, whereas a new motor would probably sieze when the pistons expanded enough to weld themselves in the bores.

Of course a Sabre could easily do the same hp/litre as that special R2800 was doing. A Sabre would only need to make about 2800hp to get the same specific power. And they were already doing this at around war's end.


Question: How reliable a source is that? Consider that a production R2800 running higher octane fuel than that test running at war emergency rpm and boost, complete with water injection was rated at only 2800hp.

[Red Admiral]

I was wrong earlier. Derby's Merlin in 1944 produced 2640hp not 2450hp as previously written. Thats 95hp/L or so.

R-2800 2800hp 61hp/L
Napier Sabre 3040hp@4000rpm 82hp/L
RR Griffon 60-something 63hp/L
V1710 1475hp 52hp/L
RR Crecy 5000hp (ish) 192hp/L + exhaust thrust

http://img.photobucket.com/albums/v12/red_admiral/re2009.gif

Reggiane 2005 with the "perfect" engine I described earlier. 46L Flat-16 Alfa Romeo Ciclone

[Wuzak]

quote:Originally posted by Red Admiral

RR Crecy 5000hp (ish) 192hp/L + exhaust thrust


Non turbocharged motors should also produce some exhaust thrust?

[Red Admiral]

Nowhere near as much as the 2-stroke Crecy. A figure of about 30% extra comes to mind. The exhaust thrust from other engines is significant. I think Groggy posted a table of it for hte Merlin somewhere here.

found it-

Super-chargergear Altitude(ft)Withoutexhaustthrust-Withexhaustthrust

MS 5,000 345 351
13,500FTH 388 400
23,500 373 399
FS
31,500FTH 419 454
40,000 377 424

[Wuzak]

quote:Originally posted by montanamotor

If there is one thing on earth, a sleeve-valve-design CAN NOT offer, it's reduced complexity...;)

Not to mention the arrangement of small cranks (one per cylinder) inside the case, one of each setting the sleeve-valve per each cylinder into it's "wobbling" motion...

And don't forget: You still had to add yet over a dozen more 90 degree-bevel-drives - one per each cylinder - to alter the rotation from the radial application like in a radial engine, into an axial array, like you would need in a barrel-engine.


Just been musing over how a sleeve valve could be operated in a barrel engine and it dawned on me that the drive system would nearly be identical to that for a radial.

The gear train for the front of the engine certainly looks complicated...

Now if I could find out exactly how the Almen's valving worked. I understand that it wasn't poppet valves, nor sleeve valves, and certainly not disc valves. It was said to cause significant friction.

[montanamotor]

Wuzak,

don't know for shure if this was definitely the timing device being used in the "old" barrel engine, but - the ASPEN-rotary valve-timing was known for it's qualities during the times when the barrel engine was constructed, yet which were bought by accepting a good amount of friction during use (in addition to ghastly being thirsty for oil, too!).

The aspen rotary valve looked like a funnel turned upside down, which formed the combustion chamber inside, and timed the exchance of gases through holes in it's wall, like the flat rotary disc does. Problem was, the funnel was rammed into it's counterpart inside the cylinderhead like a wedge by the combustion pressure inside, which in turn caused considerable friction at the walls in the cylinder head, despite all lubrication efforts, which lead to a comparatively high oil-consumption ot aspen-timed engines (no oil-seals possible here).

This problem was increased further, as the Aspen-rotary was turning at 1/2 crankshaft-speed (one timing hole only), whereas the flat rotary disc wears TWO holes for the timing, and turns at 1/4 crankshaft-speed, instead. Oil loss is negligible here, as the flat disc HAS well working oil seals to control oil consumption.

The flat disc didn't suffer at all under the gas-loads or ingreased friction, too - and hence, in my eyes, is much better suited for timing in a new barrel engine than an Aspen-funnel or any other arrangement.

I should be able to supply you with a (german) book with further details on the flat timing disc, if you like, Wuzak.

All this, combined with the flat disc's ability to enable a very freely breathing engine - i.e. POWER! - and a comparatively simple and straightforward driving gear train, makes me think that, the flat disc may be your choice of timing a new barrel engine, rather than anything else.

I have considered a possible arrangement of a barrel engine with flat disc-valves already, Wuzak. If you like, I am willing to share my thoughts with you. I may need some time to visualize them, only.

Deal?

Cheers!

Montanamotor

[Wuzak]

When I find the paper I have on barrel engines I will quote its description of the valve system for the Almen. It sounds completely different to the valve systems you describe.

As for your disc valves, my mental image is that they spin aroun an axis parallel to the cylinder axis - that is, for a barrel engine their axes would be parallel to the crankshaft axis, and would need a simple spur gear train to drive, at a reduction of 4:1.

By all means show me what you are thinking in terms of disc valves.

My only problem with disc valves is were there any WW2 production engines built using them?

Several Bristols used sleeve valves, plus the Napier Sabre. The Rolls Royce Eagle 22 was one too, but failed to get into volume production (end of war, unreliability, gas turbine/jets). Even Pratt & Whitney built an experimental engine with sleeve valves.

[montanamotor]

Wuzak,

the flat discs were thorougly developed by the DVL (DVL - "Deutsche Versuchsanstalt für Luftfahrt" - the german equivalent to NACA) and ready for use in production engines by the end of 1943. But:

1. the German's dire need for piston engines didn't allow for halting the existing production lines for a month or so, to re-tool the traditional manufacturing process for the flat discs;

b. Jet-engines seemed to be so close at hands by 1943, that the RLM decided not to invest any more money and resources in new piston-engine-developments, but rather to concentrate their efforts on the new jet-aircraft with yet-unproven jet-engines - with all known consequences.

The flat discs just work fine, Wuzak. Trust me - I know, what I am saying...! [8D]

I'll send you the info's ASAP. Promised.

Cheers!

Montanamotor

[montanamotor]

Hi, Wuzak,

I found a very well sorted scientific article about the flat discs on the internet, formatted as PDF (sorry, in german only...).

Let me have your email-address, and I'll send the PDF to you ASAP. And to everyone else, who should be interested in that stuff, too, of course! Just let me know your email-address for that. Response granted - satisfaction guaranteed!

If you need help for translating the stuff into english, you may either ask me, ore one of the other buffs able to talk in both tongues (Lightning and RT come to my mind immediately, but shurely enough, there's a whole bunch of germans - either native or "imported" - around here...).

Please keep in mind that, this PDF-article deals with the flat disc's state of the art as of 1943!!!

For today, I took the chance to redraw some of the basic features of the flat discs, instead, to adapt it to now-availlable modern materials as well as to new mechanical methods of manufacture.

For example, see this link:

http://www.voelkl.net/

Again, in german, only... - but what would you think, if I told you that, this company has specialized itself in manufacturing engine-PISTONS from pure carbon (the Formula 1 disk-brake-stuff)????

This carbon is PERFECTLY suited for manufacturing low-friction, high-wear-resistant flat-discs from it, too!!!

And it allows for a new, mechanically simpler as well as more combustion-effective shaping of the flat disc/combustion-chamber-arrangement, also. But THIS arrangement I still have in my brain only, so far. :D

Well - let's keep this thing rolling - errr, flying, I mean...

Cheers! [8D]

Montanamotor

[Wuzak]

Carbon fibre disc brakes made it onto aircraft well before they made it to F1...

Anyway, 1943 tech is just fine, as that is the tech level I am aiming at. ie see how compact an 18 cylinder barrel engine of the same capacity as an R2800 is.

[montanamotor]

Wuzak,

not Carbon-FIBRE - but pure, monolithic carbon-pistons. Hard as steel, light as a feather, and slippery like - well: You name it...:D

But - to hand you out the PDF I have for you: I need your EMAIL-ADDRESS, BUDDY!

Try again, please!

Cheers!

Montanamotor

[Wuzak]

Sorry, forgot!

wuzak_f1@hotmail.com

[Wuzak]

Thanks montanamotor,

Looks like an interesting paper. I wish I continued with German lessons when I was in school!

The disc device is different to what I was picturing. I guess it is like a sleeve valve that has been flattened out and placed at the top of the cylinder chamber.

btw, I am from the other side of the Tasman sea from NZ - in Australia, Tasmania to be precise.

[montanamotor]

Wuzak,

the first time in my life I meet a genuine, real Tasmanian Devil... :D

To help you out with your translation efforts, see this link:

http://babelfish.altavista.com

I have tried it out with excerpts from our respective rotary valve-text already - with stunning results. The translations are equisite!

Thank God, it is possible to paste and copy the text from the PDF and insert the respective textblocks into the active "babelfisch"-window without hussle. Then choose the languages concerned (here: "Deutsch ins Englische") - and press "Übersetzen" (translate) - and off the Babelfish goes...

Sadly enough, you can only submit short cuts from the text each time. So it will be work for a long, rainy Sunday afternoon, to have the rotary valve-text translated completely, I am afraid. But I have heard, rainy Sunday afternoons are not too uncommon in Tasmania - right?

Hope this is of some help to you! And maybe you can submit the finalized text here in TGplanes for the rest of the world to see, also.

Sadly, the pictures cann not be reproduced from the PDF, as far as I have tried out with no success, so far. So, if someone else should be interested to see the pics about the rotary valves, I'll submit the original PDF to him on request, too.

Have fun with it! And may the Force be with you, Wuzak...

Cheers!

Montanamotor

[Wuzak]

quote:Originally posted by montanamotor

Sadly enough, you can only submit short cuts from the text each time. So it will be work for a long, rainy Sunday afternoon, to have the rotary valve-text translated completely, I am afraid. But I have heard, rainy Sunday afternoons are not too uncommon in Tasmania - right?

You have been misinformed.......

Well, to be strictly correct it depends where you are. I live in the North of the state in a place called Launceston. It has higher annual rain than where I am from (Hobart in the south) but still not a great deal (ie less than Sydney). Now, the West Coast, where I worked for a few months, has much more rainfall - 3 or 4 times as much, in fact.

But in the past few years we have had very little rain statewide. So much so that the state electic company is seeding clouds trying to get it to rain to fill their hydro reservoirs.

Anyway, it is now Spring here, and that generally means a bit of mixed weather, a bit more wind than usual, but trending to warm and sunny. Which is what the prediction is for the rest of the week - warm, sunny and windy!

Thanks for the translator link...I will give that a go later. As for the pictures, Adobe has a way of selecting pictures to copy. All you need to post it in here is a host for the pic on the web.

And thanks for the file. I will post it when I get it translated.