SaQSoN, since you're here, lemme just say congrats and a job well done on the CL.II.

Thanks. Hopefully, there will be more stuff coming from our team to the RoF soon.

I think the british called the D.IIIau a 200hp engine. Thats why.
The engine is modelled correct, there was alot of information given to the team about it.

First, i like the Cl.II very much ! It looks phantastic, form and details are top notch.

My books say the CL.II was used from november 1917 on (so a "late" plane), and "used the Mercedes D.III series engines". It makes sense to assume some received the IIIa and au versions then, depending probably on role. The book "Aircraft types of WW1" (translated, german book from the 1970ies) also states it was built in masses, but no exact numbers given there.

Took the Halberstadt CL.II out for three flights yesterday on the Syndicate server, without making any test flight before. Handles nice, rolls a bit sluggish to the right. Good visibility, but observer blocking rear view. Landing holds no perils, just let it do enough speed when touching the ground, and let it flare out and settle smooth , which is not difficult at all. Ground loop easy to counter with engine running.

First two flights i took out artillery positions at enemy side near the front, all on the Syn server.

In the first flight i dropped my bombs and made back for the front, low. A SPAD attacked, and my AI gunner damaged it (trailing fuel), but it also damaged my engine, which seems to me much more prone to enemy fire, than e.g. the DFW - only logical with the DFW's engine armour. Emergency-landed with dead stick in No-man's land, but close to my side. Did a ground loop, but no damage to lower wing.

Second i finished off the arty positions, and made it back unharmed, if not unharrassed.

Third flight was a ball. Flew over the front high, and then descended to attack trucks far behind the frontline. Managed to destroy all three in one run and wanted to drop the rerst on the nearby aerodrome, when my observer started firing away - SPAD !
Was hit, but not badly and began to circle tight to get the SPAD in my gunsight. Was too slow though, and another stream of bullets dameged my left wing, killed my gunner, and made us trail more petrol. I still had some small bombs left, but completely forgot them. Managed to shoot at the SPAD, but no reaction. Going vertical and falling back i managed to damage the SPAD now trailing coolant. Another circle and it also trailed fuel. Then we circled again and when i had it in my gunsight several times i realized i had no ammuntion left . But the SPAD was unable to run away, or shoot at me due to me evading his attacks everytime.
So we circled until the SPAD had to land, and i made my way back. Had a short idea of shooting at him with my Colt, but did not want to be an a$$. Was not awarded a "kill" (seems he managed to land before killing his engine) but saluted anyway, was a great fight .

So survived three attacks, and landed all three times without shredding the CL.II (3rd time the SPAD making a wreck of it though, but made it home holed and trailing fuel).

Was great fun, and the CL.II is not such an Ueber-plane like the Brisfit. For all i have seen on youtube videos, the performance of the Brisfit is unreal, in RoF.
If this was the first journeyman's piece of new team members .. congrats. Very. well. made.

Also it make me real enthusiastic that we have the D.IIIau engine now, which may be later built into some Albatros D.V versions, and other planes ..
It may well have had 200 hp, a lot of pilots in Zuerls' "Pour le mérite" report about this number. Some british test personnel fitted it with the wrong carburettor, but no one ever seems to have took the german high-octane "Fliegerbenzin" into account, with which the engine was never tested by the Entente.


Thanks and greetings,
Catfish

Great read, thanks Catfish.

If the Mercedes D.IIIaü was just now introduced into the sim, which engine is installed in the Fokker D.VII? The Mercedes powered version should also make use of this engine AFAIK!

The Fokker D.VIIs in Rise of flight come currenty in two versions:

- either the D.VII with Mercedes D.III engine which makes it a bit underpowered, and is historically not correct
- or the D.VII F with BMW D.IIIa engine with "Hoehengas" lever, the "F" being for Max Fritz, the engine's designer that had developed this version out of the Rapp engine.

In RoF there is no D.VII currently with the Mercedes D.IIIa (170-185), the Mercedes D.IIIaü (180-200), or the Mercedes D.IIIavü (180-220 hp) engine, only the two mentioned above - yet.


(Regarding the HP (english horse power) or PS (german Pferdestaerke) performance indicators there is a lot of confusion, being based on british tests and not understanding the german nomenclature.
British tests placed the wrong carburettors on the Mercedes D.IIIa, aü and avü engines, only tested them at sea level and furthermore did not use german high octane "Fliegerbenzin" with Benzol added for higher octane rate (making the engine knock less, and removing pinging).
So e.g. the Mercedes D.IIIaü engine developed 200 horse powers tested by the british, but:
- fitted the wrong carburettor
- tested it at sea level
- used no high octane fuel
The wrong carburettor indeed made the engine produce 200 hp at sea level, but it would have been less than 156 hp at 3000 meters.
Instead in reality and german use it had a carburettor and fuel that let the engine produce 170 hp at sea level, while it was around 200 at higher altitudes.
With the BMW D.IIIa engine and Hohengas "engaged" the D.VIIF would even produce 240 hp at low altitudes, but not for very long lol.)


Even not quite right in the english Wiki, but numbers and types are correct, if not always their performance:

" ... Many sources erroneously state that the D.VII was equipped with the 160 hp Mercedes D.III engine. The Germans themselves used the generic D.III designation also to describe later versions of that engine. In fact, the earliest production D.VIIs were equipped with 170-180 hp Mercedes D.IIIa. Production quickly switched to the intended standard engine, the higher-compression 134 kW (180 hp) Mercedes D.IIIaü. It appears that some early production D.VIIs delivered with the Mercedes D.IIIa were later re-engined with the D.IIIaü.

By the summer of 1918, a number of D.VIIs received the "overcompressed" 138 kW (185 hp) BMW IIIa, the first product of the BMW firm. The BMW IIIa followed the SOHC, straight-six configuration of the Mercedes D.III, but incorporated several improvements. Increased displacement, higher compression, and an altitude-adjusting carburetor produced a marked increase in speed and climb rate at high altitude. Because the BMW IIIa was overcompressed, using full throttle at altitudes below 2,000 m (6,700 ft) risked premature detonation in the cylinders and damage to the engine. At low altitudes, full throttle could produce up to 179 kW (240 hp) for a short time. Fokker-built aircraft with the new BMW engine were designated D.VII(F), the suffix "F" standing for Max Friz, the engine's designer. Some Albatros-built aircraft may also have received a separate designation.

BMW-engined aircraft entered service with Jasta 11 in late June 1918. Pilots clamored for the D.VII(F), of which about 750 were built. However, production of the BMW IIIa was very limited and the D.VII continued to be produced with the 134 kW (180 hp) Mercedes D.IIIaü until the end of the war.

D.VIIs flew with different propeller designs from different manufacturers. Despite the differing appearances there is no indication these propellers gave disparate performance. Axial, Wolff, Wotan, and Heine propellers have been noted."


In the assumption to now have confused everyone, i rest my case

Thanks and greetings,
Catfish

From the RoF forum:



http://riseofflight.com/Forum/viewtopic.php?f=49&t=28544&start=90

"old vertical pump" was one-cylinder, while the horizontal one was two-cylinder, with higher output. Apart from the pump, externally the au engine had different design of the carburetor and intake collector.

Catfish,

Broadside already has criticized me for arguing this point on two forums, so I'll make it brief.

"It makes sense to assume" and "probably" is not documentation.

Actually, it's nothing but a guess.