relation to the fore output gear a drive gear is rotatably affixable within the housing and is affixed for corotation with a drive shaft the drive gear has a fore portion that is positioned in driving relation to the intermediate gear and an aft portion that is positioned in driving relation to the aft output gear improved stability characteristics are imparted by supporting the drive shaft at two points within the case and also by positioning the drive and the output shafts in vertical alignment the adaptability of the gear based transmission to being coupled with an automobile engine confers improved noise and efficiency characteristics application_number US 55736500 A description a description of the preferred embodiments of the present invention will now be presented with reference to fig1 8 the four embodiments of the airboat transmission 10 10 u2032 10 a and 10 a u2032 of the present invention to be discussed herein are shown from the side in fig1 7 and 8 and are designed to drive a pair of coaxial counter rotating propellers 20 and 30 the transmission comprises a housing 50 that has an interior space 502 a fore side 504 and an opposed aft side 506 the fore side 504 is affixable to the engine 39 s bell housing or may be an integral part thereof the aft side 506 has an opening 505 for admitting propeller shafts 22 32 the fore side 504 has an opening 503 for admitting a drive shaft 12 it is preferred.