First flown in mid-1917, the Zeppelin-Staaken R VI, with 18 examples built, was to be by far the most numerous of the giant, long ranged R-planes. Powered either by four 245hp Maybach Mb IVs, or four 260hp Mercedes D IVa engines, mounted back to back in twin nacelles to drive two pusher and two tractor propellers, the R VI's top level speed was 135km/h, while its normal range with a 1000kg bomb load was around 880km. Delivered to Rf Abt 501, by now transferred to the Western Front, the RVIs sometimes operated alongside their smaller G type bretheren in raids against the English mainland and more distant French ports and cities.The Navy operated a sole, float-equipped example of this bomber under the designation Zeppelin-Staaken Type L, serialled 1432.