Gotha G . II The Gotha G . II series was a heavy bomber used by the " Luftstreitkräfte " ( Imperial German Air Service ) during World War I . Design and development . The Gotha G . II was an entirely new biplane designed by Hans Burkhard , who had previously reworked Oskar Ursinus ' s design for the G . I to make it suitable for mass - production . Burkhard abandoned the G . I ' s unorthodox configuration in favor of a more conventional design with the fuselage mounted on the bottom wing rather than the top . In deciding this , he had the benefit of greater pilot experience to draw upon . The difficulties of asymmetric thrust created by losing an engine on a twin - engine design had proved to be not nearly as bad as Ursinus had originally believed , and therefore the G . I ' s unusual design was really an answer to a non - existent problem . Furthermore , Burkhard had the opportunity to rebuild a crashed G . I ( serial number " 9 / 15 " ) and re - arrange its components to place the fuselage on the lower wing , and found this design workable , while also removing the grave danger to the crew that landing accidents posed . The G . II carried a crew of three and a defensive armament of two 7 . 92 mm ( . 312 in ) machine gun s . The forward section of the fuselage was skinned in plywood , with the remainder covered in fabric . The fuselage and two very large nacelles were mounted on the lower wing . Each nacelle contained fuel and oil tanks beneath a geared eight - cylinder 160 KW ( 220 hp ) Mercedes D . IV engines driving pusher propellers . The undercarriage was unusual , being quadricycle in arrangement with a pair of wheels mounted at the front and rear of each engine nacelle . This feature was intended to remove the possibility of a nose - over on landing . In fact , the nacelles and undercarriage constituted fully self - contained , wheeled units intended to facilitate construction and maintenance . The entire aircraft was intended to be easily dismantled so that fuselage , engines , and wings would easily fit onto three railway flatcars . The G . II prototype first flew in March 1916 , and testing revealed several shortcomings . The most significant problem was that the aircraft was not capable of carrying the bombload that was specified by the " Idflieg " . This was solved by a redesign of the wing cellule to extend its span . At the same time , it was changed from a two - bay to a three - bay structure . The second issue was that the undercarriage arrangement made for very long and uncontrollable landing rolls . This was solved by changing it to a conventional tailskid configuration . Other revisions included horn - balanced ailerons and a triangular vertical fin . In this configuration , production commenced in April 1916 . Operational history . The G . II entered operational service in August 1916 , with eight of the initial production batch of 10 deployed to the Balkan front . Of the two others , one remained with Gothaer and the other was severely damaged in an accident during evaluation . Nothing today is known about the type ' s performance in combat , but of the eight on active service , no more than four appear to have been operational at any one time ( October 1916 ) . By February 1917 , this number had dwindled to one aircraft only , and from April none remained in service . Part of the problem no doubt lay with their engines . The Mercedes D . IV was plagued by severe crankshaft vibration that resulted in frequent crankshaft failures .