For use on very large aircraft, Argus designed and built the As 5 WW-24 water-cooled piston engine.

The As 5 consisted of six banks of cylinders arranged around a common crankshaft with a single output shaft.

Each cylinder drove the crankshaft through a master and slave big end, similar to most radial engines.

Individual cylinders with sheet metal water jackets shared the aluminium alloy heads, four to a bank.

Although some testing was carried out, the As 5 never flew and was abandoned along with the very large aircraft projects it was intended to power.