The Maybach Mb.IV, originally designated Maybach HS, (only related to the Mb IVa by layout and size), was a straight-six piston engine of output, originally developed for use in airships. It was also used for large aircraft such as the Zeppelin-Lindau Rs.I seaplane.
Variants of the original HS engine included the Maybach HS D, Maybach HS K and Maybach HS Lu. The latter engine was used in the Zeppelin-type and Schütte-Lanz Type E airships.