Under the directorate of Dr. Straus, Argus started the construction of aero-engines again after lifting the construction-limitations. Since 1928, Argus concentrated under F. Dinslage as technical director and Dr. Christian as chief constructor on air-cooled aero-engines in the sports-, training- and touristplane-class. In the spring 1929 the Argus AS 8 is introduced as an 80 HP four-cylinder-engine with hanging cylinders. In the tourist plane contest 1930, all three winning planes (Bf M23) have been equipped with this progressive engine.
The german newspaper ‘Deutsche Allgemeine Zeitung’ reports in its edition from the 16th October 1930 (cited after: Kyrill v. Gerstorff ‘Die deutsche Luftfahrt – Flugmotoren und Strahltriebwerke’, Bernard & Graefe Verlag Bonn):
‘Argus AS 8 special in the tourist plane contest. That the aircraft of the 3 winners Morzik, Poß and Notz all used Argus engines, does not mean, that the Argus engine had won the victory over the others. But the Argus engine shows features, which entitle it to the highest hopes. It is an aircooled engine with 4 cylinders in a row. When for the first time, namely at the war, the trial with hanging cylinders was made, the pilots and the mechanics, who had to handle it, were not satisfied, moaned, that everything will be blurred and thaught, that they could not predict a future for the configuration. In the meantime, Argus company developed the configuration of hanging cylinders in lines – as opposed to the radial form, which is common otherwise – further and further. The in-line engine has the obvious advantage, that it presents less area to the aerodynamic drag, which is especially important at small aircraft for tourist and sport purposes and also affects the shaping of the fuselage. The configuration of the hanging cylinders, which distincts the Argus engine substantially from the foreign in-ine engines, a high exposure of the airscrew and good visibility conditions are achieved. It is clear, that standing cylinders impair the visibility. Thus, the british press, after facing the Argus engines last year in London at the Olympia for the first time, predicted a new development of aviation because of them. Whereas 25 competitors had to give up during the contest and 11 of them due to engine failures namely of long tested engines, only one competitor with Argus engine had to give up, but could however continue his flight outside the contest.
Deutsche Allgemeine Zeitung, edition from the 16th October 1930
Consistently one sample has been used, which displayed a nominal and continuous power of 80 HP (DIN) and a maximum power of 95 HP with a crankshaft-speed of at average 1470 min-1 (throttled back 1 410 min-1) upto 1 750 min-1. As regards the material consumption the recently finished tests at the Deutsche Versuchsanstalt für Luftfahrt (German experimental station for aviation) produced the following numbers: fuel consumption at maximum power 212 g/PSh, throttled back 236 g/PSh. A specific advantage is the humble annoyance of the prop-wash in the open aircraft, it is due to the higher position of the crankshaft and also due to the reduced engine speed. It is, Notably by the low position of the cylinders avoided, that occupants will be annoyed by oil-splashes. Also the exhaust-noise doesn’t molest any more, since the exhaust collector tube is located below the fuselage. In addition there is a smooth running of the engine without vibrations. That the director of the factories Dinslage is permanently named as the inventor is denied by himself and defers justifiably so to the collaboration in the company; in any case the chief-constructor Dr. Christian has an essential part.’
The Argus AS 8R, which was used at almost all german aeroplanes in the contest 1932, was a further development of the proven Argus AS 8 A/B, which among other was adjusted to the higher power through the following measures (ZFM 19/1932, page 578)
Advantages
- Increase of the compression ratio from 5.36 to 5.8
- Improved cooling by increasing the numbers of cooling fins at the cylinder head and the cylinder track
- increasing the heat dispensing areas on the piston
- improving of the casing- and oil-cooling by segregating the oilbin from the engine casing and internal cooling through the air stream
- improvement of the cylinder charging by enlargement of the carburator- and suction line cross section and adaption of the valve timing
The following drafts and facts relate to the weaker predecessor Argus AS-8 B, since I could not get grip on further informations about the Argus AS-8 R. They are derived from manuals from the aviation archive Hafner, whom I would like to thank for the permission to publish them.
Technical Data:
Engine type:
Air cooled 4 cylinder-in-line-engine with hanging cylinders
Performance ratings:
| 5-minutes-power (Max. Takeoff-power) Sealevel | 130 PS @ 2200 U/min |
| 30-minutes-power Sealevel | 125 PS @ 2150 U/min |
| Max. continuous power | 115 PS @ 2090 U/min |
| Max. RPM | 2350 U/min |
| Fuel consumption | See Diagram |
| Oil consumption (Average) | 1,2 kg/h |
Dimensions
| Bore | 120 mm |
| Stroke | 140 mm |
| Displacement per Cylinder | 1, 583 ltr. |
| Total Displacement | 6,333 ltr. |
| Compression ratio | 1 : 5,3 |
Weights
| Empty weight | 116,0 kg |
| Rupp-Flange-Hub | 3,6 kg |
| Cowling | 2,8 kg |
| Cranking mechanism with crank lever | 4,0 kg |
| 1 Fuelpump with piping optionally 2 fuelpumps with piping | 1,2 kg (2,0 kg) |
| Total weight with all of the above: | 127,6 kg |
General Dimensions
| Gross Length (without Hub) | 1075 mm |
| Max. height | 731 mm |
| Max. width | 470 mm |
PROPELLER
| Type | Ground adjustable Propeller |
| Diameter | 2,10 m |
| Propeller area | 3,46 m² |