The Merćep 1912 aka Merćep-Rusjan Military-Monoplane of 1912 or Rusjan-Novak No.2, was the second design after the crash of the Slovenian aviation pioneer Eduardo Rusjan. Earlier, Eduardo Rusjan had moved with his brother to Zagreb, Croatia, where Guiseppe Rusjan and Dragutin Karlo Novak then continued to build aircraft for the “Agramer Aëroplanfabrik M. Merćep”, set up by the businessman Mihajlo Merćep in Zagreb.
Engine: Gnome, 50 h.p. Span: 32½ ft / 10 m Wing area: 204 sq. ft / 19 m² Length: 23 ft / 7 m Weight: 617 lb / 280 kg Useful load: 661 lb / 300 kg Number built: 1
The Mercedes D.IV was an eight-cylinder, liquid-cooled inline aircraft engine built by Daimler Motoren Gesellschaft (DMG) and used on a small number of German aircraft during World War I.
The design was based around the pistons of the ubiquitous D.III 6-cylinder design and developed 162 kW (217 hp), making it a Class IV motor under the classification system then in use in Germany. When the reliability of the engine proved disappointing, it was supplanted in production by the unrelated six-cylinder Mercedes D.IVa. Specifically, the long crankshaft used in extending the original straight-six design to a straight-eight proved susceptible to breakage.
Applications: AEG C.V AEG G.III AEG R.I AGO C.II AGO C.VIII Albatros C.V DFW R.I Gotha G.II LVG C.IV various Riesenflugzeuge (R-planes)
Specifications Type: 8-cylinder water-cooled inline aircraft piston engine Bore: 140 mm (5.5 in) Stroke: 160 mm (6.3 in) Displacement: 19.7 L (1,200 in³) Length: 1,990 mm (78 in) Width: 600 mm (24 in) Height: 1,040 mm (41 in) Dry weight: 365 kg (800 lb) Cooling system: Water-cooled Power output: 162 kW (217 hp) at 1,400 rpm
The Mercedes D.III, or F1466 as it was known internally, was a six-cylinder, liquid cooled inline aircraft engine, first run in 1914, built by Daimler and used on a wide variety of German aircraft during World War I. The initial versions were introduced in 1914 at 160 hp, but a series of changes improved this to 170 hp in 1917, and 180 by mid 1918. These later models were used on almost all late-war German fighters, and its only real competition, the BMW III, was available only in very limited numbers.
The D.III was based on the same pattern as the earlier Mercedes D.II, suitably scaled up for higher power settings. Like most inlines of the era, it used a large aluminum crankcase as the main structural component, with separate cylinders made from steel bolted onto it. The technology for screwing a threaded cylinder of steel into an aluminum crankcase did not exist at that time. Jackets for cooling water covered the top 2/3 of the cylinder, feeding a radiator via connections at the back of the engine. The D.III featured a rather prominent overhead cam operating the single intake and exhaust valves, powered by a shaft running up from the crankshaft at the rear of the engine. Ignition was provided by two sets of spark plugs, one located on either side of the cylinders, each powered by a separate magneto for redundancy. The ignition cables were protected in tubes running down either side of the cylinders. Fuel was fed into the cylinders via pipes on the left side of the engine as viewed from the rear, supplied from a twin-barrel carburetor located just above the crankcase. Both the fuel and oil reservoirs were pressurized by an air pump run off the crank.
The only obvious design change from the earlier D.II was to use separate cooling jackets for each cylinder, whereas the D.II used one jacket for every two cylinders. Daimler also used the pistons of the D.III to produce the reduction geared, eight-cylinder 220 hp Mercedes D.IV during this period, but it did not see widespread use.
The original D.III was introduced in 1914. While it saw widespread use in early examples of the C-series of two-seat general-purpose biplanes the D.III did not see use in fighters until 1916 when the fighters grew to need that level of power; earlier designs were generally powered by lighter rotary engines of about 110 hp or by water cooled inline engines in the 100 to 120hp range such as the earlier Mercedes D.II. By 1917 the D.III was being widely used in fighters, most notably on the famous Albatros D.I. Production of this version was essentially wound down by May 1917, with only a handful continuing to be delivered until October. British hp ratings being slightly different to the German PS or (Pferd Starke) standard, it is probable that this engine would have had a slightly higher rating under British HP numbers.
Development of the basic design led to the slightly modified 170 hp D.IIIa, which took over on the production lines in June 1917. The main change was to change the piston profile to have a flat head instead of the former concave one, thereby slightly increasing maximum compression. Other changes were mainly in design details, notably a redesigned crankcase and new carburetor. Many of the accessories were also redesigned or moved around on the engine. This model was produced only briefly, for use on the Albatros D.III but there are indications that possibly some early Albatros (Alb.) made Fokker D.VII’s were also equipped but probably had the engines upgraded or replaced as quickly as possible. This engine has been referred to in postwar British analysis as generating 180 hp. A more “radical” upgrade was the 180/200 hp D.IIIaü, introduced in late 1917, the D.IIIaü was a standardized refinement of the D.III and D.IIIa design and the ü designation was never official. This engine changed the pistons again, this time to a domed profile that further increased the maximum compression – the ü was for “über”, meaning “overcompressed”. Additionally, a new altitude-compensating carburetor was added, which improved performance at higher altitudes. To support operations at these altitudes, water from the radiator was used to heat the air intake and prevent icing in the carburetor. The aü model, which included upgraded D.III and D.IIIa engine blocks, was the most prolific German fighter engine of 1918 and designed into most fighter designs from late 1917 on. This included most of the entries in the First Fighter Competition at Adlershof in January 1918, notably the Fokker D.VII. In British post war evaluation the D.IIIaü demonstrated 200 hp according to the British standards.
A final version attempting to keep the D.III block competitive was the 200 hp (200-217 hp) D.IIIav (or avü), introduced mid-October 1918. The av used slightly longer pistons made of aluminum (possibly a first for a production engine), increasing the compression yet again, while at the same time allowing them to move faster due to the reduced weight. The maximum allowable RPM increased from 1,400 in the earlier models to 1,600 in the av, accounting for most of the gains in power. It is unclear if any av’s saw service use. The increased use of Benzol in German aviation fuel may have helped this final upgrade of power, it’s higher octane rating being better suited for the higher compression ratio.
All of the D.III series were generally very similar to other models, with the exception of the piston profile and carburetor details. It appears that upgrades were available for many of the engines, certainly for the III to IIIa, and IIIa to IIIaü. It would seem unlikely that early III’s would ever make it to the IIIaü standard, as they would almost certainly have been worn out in service before then. A more obvious change concerned the layout of the rocker arms that operated the valves. Early models had square cases positioned directly over the cylinders with the rocker arms exiting through vertical slots cut into the sides of the boxes. In later versions of the engines, the boxes were moved rearward and the cylindrical rocker arm shafts protruded forwards through the front surfaces of the boxes, operating the now fully exposed rocker arms with the exposed shaft ends. The newer arrangement can be seen in the image above (compare with the image of the D.II) and were stated as being interchangeable as a set with the complete camshaft, rocker boxes, rocker arms and valve springs, with the D.III’s earlier cam drive system design.
Confusingly, the “ü” was not an official part of the name. This leads to a number of problems in various references, which often confuse the IIIa with the IIIaü, listing the former as a 180 hp engine. It should also be noted that there are two D.IV engines, one the eight-cylinder based on the D.III pistons, and the later six-cylinder D.IVa which was essentially unrelated.
The D.III line of engines would find themselves eclipsed in performance by the BMW IIIa of 185 and then 200 hp (British rated it at 230HP) in 1918, however, the small number of BMW’s produced ensured that the Mercedes D.III series would be the primary German fighter engine up to the last month or two of the war and it would still be seen in very large numbers even at the end. At the end of the war the D.IIIaü would still be the numerically predominant German fighter engine. As a result the Fokker D.VII’s (those not equipped with BMW IIIa’s) and the Pfalz D.XII’s would be engine limited in performance (as opposed to “airframe-limited”) and yet would still be formidable adversaries to their Allied counterparts. The D.IIIaü was considered the optimum engine for the Roland D.VI, Pfalz D.IIIa, and Albatros D.Va fighters whose airframes were of an earlier, “all-wood” generation in design.
Variants:
Mercedes F1466 Company designation for the D.III
D.III The original producction version directly developed from the Mercedes D.II developing 150 – 160 hp
D.IIIa An up-graded D.III introduced in 1917 rated at 170 hp
D.IIIaü An unofficial designation, (ü for über), for D.IIIa engines with domed pistons, operating “over-compressed”, (at a higher compression ratio). These engines were not able to operate at full throttle at sea level, utilising a self compensating carburettor. 180/200 hp
D.IIIav D.IIIa engines with the domed pistons made from Aluminium alloy giving the higher compression ratio as well as a higher operating rpm and thus more power. 200 hp (200-217 hp)
D.IIIavü alternative unofficial designation for the D.IIIav
Applications: AEG C.IV AGO C.I Albatros C.I Albatros C.III Albatros C.XIII Albatros D.II Albatros D.III Albatros D.V/D.Va Albatros W.4 Daimler L11 Daimler L14 Fokker D.IV Fokker D.VII Halberstadt CL.II Halberstadt CL.IV Hansa-Brandenburg C.I Series 63 Hansa-Brandenburg W.12 Junkers CL.I LFG Roland C.II LFG Roland D.II LFG Roland D.VI Rumpler C.I Rumpler 6B Pfalz D.III Pfalz D.XII R-Planes
Specifications:
D.IIIaü Type: 6-cyl. water-cooled in-line piston engine Bore: 140 mm (5.51 in) Stroke: 160 mm (6.30 in) Displacement: 14.8 l (903.15 cu in) Length: 1,650 mm (64.96 in) Width: 490 mm (19.29 in) Height: 1,070 mm (42.13 in) Dry weight: 310 kg (683 lb) Valvetrain: DOHC rocker operated single inlet and exhaust valves. Fuel system: Dual Mercedes twin-jet carburettors Fuel type: Gasoline Oil system: Pressure system; multiple plunger pump Cooling system: Water-cooled Power output: 129.75 kW (174 hp) at 1,400 rpm (rated power at sea level), 152.12 kW (204 hp) at 1,600 rpm (maximum power at altitude) Specific power: 0.2259 hp/cu in (10.281 kW/l) Compression ratio: 4.64:1 Specific fuel consumption: 0.412 l/kW/hour (0.541 pt/hp/hour) Oil consumption: 0.027/kW/hour (0.0355pt/hp/hour) Power-to-weight ratio: 0.492 kW/kg (0.299 hp/lb) BMEP: 0.75 MPa (109.1 psi)
The Mercedes D.II was a six-cylinder, liquid cooled inline aircraft engine built by Daimler during the early stages of World War I. Producing about 110 to 120 hp, it was at the low-end of the power range of contemporary engines, and was generally outperformed by rotaries whose power-to-weight ratio tended to be much better. It also had stiff competition from the Ferdinand Porsche-designed 120 hp Austro-Daimler 6. The D.II was produced only briefly as a result, but its design formed the basis for the later Mercedes D.III which saw widespread use throughout the war.
The D.II was based on the Austro-Daimler to a large degree. Like the Austro-Daimler, it was built up from the crankcase, which was milled from two pieces of cast aluminum bolted together at their midline. The cylinders were separately milled from steel and bolted to the top of the crankcase. Steel sleeves were fitted over the cylinders and welded on to form a cooling jacket. Much of this complexity is due to the differential rates of expansion of steel and aluminum, which precluded screwing the cylinders into the crankcase, and the alloys of the era meant that an aluminum cylinder was not possible. Both engines also used a scavenger pump to pump oil out of the crankcase to a separate cylinder, where a second high-pressure pump supplied oil to the engine. This arrangement allowed for a much smaller “sump” on the bottom of the crankcase, reducing the overall size of the engine, although in the case of the D.II it was not nearly as much as the Austro-Daimler.
Where the D.II differed from the Austro-Daimler was largely in mechanical arrangement. For instance, the D.II featured a single overhead cam, powered by a shaft leading up from the crankshaft at the rear of the engine, whereas the Austro-Daimler had a more conventional valvetrain using pushrods driven from the crankcase. Another unique feature was the ability to shift the camshaft to a half-compression position for starting. The D.II used two carburetors located together on one side of the engine, feeding the cylinders through two manifolds; the Austro-Daimler separated its carburetors to locate them closer to the cylinders they fed. The D.II also used a unique cooling jacket design, with every two cylinders being covered by a single jacket.
The D.II was fairly quickly replaced by the D.III, and ended production around 1916. The D.III was essentially a scaled-up D.II, although it abandoned the paired cooling jackets.
D.II Type: 6-cylinder, inline piston engine Displacement: 579 cu in Dry weight: 449 lb Reduction gear: Direct drive, left-hand tractor Power output: 120 hp at 1,400 rpm
The Mercedes D.I was a six-cylinder, water-cooled, inline engine developed in Germany for use in aircraft in 1913. Developing 75 kW (100 hp), it powered many German military aircraft during the very early part of World War I.
Applications: AEG B.I AEG G.I Albatros B.I Albatros G.I Aviatik B.I DFW B.I DFW Floh Fokker D.I
Specifications:
D.I Type: 6-cylinder, inline piston engine Reduction gear: Direct drive, left-hand tractor Power output: 75 kW (100 hp)
The Menasco Buccaneer was a series of six-cylinder, air-cooled, in-line, inverted, aero-engines, that were manufactured by Menasco Motors Company for light general aviation and sport aircraft during the 1930s and 1940s.
The six-cylinder Menasco engines had the name Buccaneer, while the four-cylinder engines had the name Pirate. The Menasco engines came in both supercharged and normally aspirated models. The supercharged models, with the S suffix added to their designation, had superior performance at higher altitudes with a relatively small increase in dimensions and weight.
Variants: Menasco A6 Buccaneer Menasco B6 Buccaneer Menasco C6 Buccaneer Menasco C6S Super Buccaneer Menasco D6 Super Buccaneer
Specifications:
Menasco B6S Buccaneer Type: 6-cylinder, air-cooled, in-line, inverted engine Bore: 4.5 in (114 mm) Stroke: 5.125 in (130 mm) Displacement: 489 cu in (8 L) Length: 60.125 in (1,527 mm) Width: 15 in (381 mm) Height: 28.3 in (719 mm) Dry weight: 423 lb (192 kg) Valvetrain: 1 inlet and 1 exhaust valve per cylinder Fuel system: 1 Stromberg Carburetor Fuel type: 73 octane Cooling system: Air Power output: 200hp at 2,250 RPM max/150hp at 2,025 RPM cruise Compression ratio: 5.5:1 Power-to-weight ratio: 2.82 lb/hp at cruise
The Menasco 4 Pirate series were 4-cylinder, air-cooled, in-line, inverted, aero-engines, for use in light general and sport aircraft during the 1930s and 1940s. The Menasco engines were interesting in that they came in both normally aspirated and supercharged forms, with the supercharged models exhibiting superior performance at higher altitudes, with a relatively small increase in dimensions and weight. The supercharged models had the S suffix added to their designation to show supercharging.
Variants: Menasco A-4 Pirate (also listed as Menasco 4A) 90hp
This machine was built at the Sint-Job-in-‘t-Goor airfield, Belgium, in the hangars of baron Pierre de Caters, by the Swedish inventor Janne Mellander, who lived in Antwerp at the time. In 1911 he was granted French patent No. 422954, which disclosed some details of his rather fragile-looking machine, which was equipped with an automatic stabilization device and had the wings mounted very high on a secondary fuselage.
The VCA-1 is a tiny single-seat, low-wing monoplane of all-metal construction. The wing section is NASA GA(W)-1 with no sweepback. It has a constant chord with plain ailerons and electrically operated flaps. The fuselage uses 2024-T3 aluminum alloy. Landing gear are nonretractable tricycle type, and the Continental 0-200 fiat-four engine drives a two-blade Sensenich fixed-pitch propeller. The cockpit is enclosed and sweeps back to a combination fuselage/T-tail empennage.
