the following description of the preferred embodiment ( s ) is merely exemplary in nature and is in no way intended to limit the invention , its application , or uses ; referring to fig1 - 16 , a synchronization cross - feed system 200 in accordance with the invention is described . elements common to fig1 - 11 will be identified with the same reference numerals . specifically referring to fig1 , a cross - section of a thrust reverser 202 , looking aft , is shown with synchronization cross - feed system 200 spanning a lower bifurcation area 204 of thrust reverser 202 and linking thrust reverser actuation systems 206 of left and right sides 203 , 205 , ( as oriented in fig1 ) of thrust reverser 202 . each thrust reverser actuation system 206 can illustratively be the thrust reverser actuation system described with reference to fig1 - 11 . specifically referring to fig1 - 16 , synchronization cross - feed system 200 is shown in greater detail . synchronization cross - feed system 200 has left and right coupling assemblies 212 , 213 ( as oriented in fig1 - 16 ) having housings 208 , 209 supporting respective bearing assemblies 210 . left coupling assembly 212 has a telescopic coupling shaft 214 slidably coupled to a synchronization shaft coupling 216 affixed to an end of a synchronization shaft 218 . right coupling assembly 213 has a fixed coupling 220 coupled to an end of a synchronization shaft 224 . synchronization shaft coupling 216 and fixed coupling 220 are generally cylindrical , having bores in distal ends 219 , 221 which respective ends of synchronization shafts 218 , 224 are received . distal ends 219 and 221 are machined as double square ends and the ends of synchronization shafts 218 , 224 that are received in the double square machined ends 219 , 221 are illustratively swaged into squares . it should be understood that right coupling assembly 213 could have the telescopic coupling shaft 214 and the left coupling assembly 212 could have the fixed coupling 220 . synchronization shaft coupling 216 and fixed coupling 220 illustratively include a threaded portion 226 , 228 , respectively , and shoulders 230 , 232 , respectively . a threaded bearing retainer 234 is threaded onto threaded portion 226 of synchronization shaft coupling 216 to retain bearing 236 of the bearing assembly 210 on left coupling assembly 212 against shoulder 230 to retain bearing 236 in place . similarly , a second bearing retainer 234 is threaded onto threaded portion 228 of fixed coupling 220 retain bearing 236 of bearing assembly 210 on right coupling assembly 213 in place . left coupling assembly 212 further includes a pin 238 radially extending through synchronization shaft coupling 216 that holds a bearing retainer 240 in place . bearing retainer 240 holds bearing 242 of bearing assembly 210 in left coupling assembly 212 in place . telescopic coupling shaft 214 includes wheel 244 having engagement teeth 246 extending radially outwardly around a proximal facing side 245 and extending axially therefrom toward fixed coupling 220 . wheel 244 also has tapered engagement nose 248 extending axially from the center of proximal facing side 245 toward fixed coupling 220 . wheel 244 and engagement teeth 246 are shown in more detail in fig1 . wheel 244 further includes a cylindrical shaft 250 that extends from a distal facing side 247 of wheel 244 over synchronization shaft coupling 216 and is slidably secured thereon by a pin 252 . a proximal end 254 of synchronization shaft coupling 216 has a spring receiving bore 256 therein that receives a spring 258 that extends within cylindrical shaft 250 of telescopic coupling shaft 214 to a spring receiving recess 259 in distal facing side 247 of wheel 244 . housing 208 of left coupling assembly 212 has a radially outwardly extending flange 262 at a proximal end 260 . flange 262 is secured to a fixed element of the thrust reverser , such as a torque box 57 of the left side of thrust reverser 202 , to secure left coupling assembly 212 in place . fixed coupling 220 has a bore 266 therein that opens at a proximal end 264 of fixed coupling 220 . proximal end 264 has engagement teeth 268 around the opening of bore 266 . engagement teeth 268 extend axially toward telescopic coupling shaft 214 . engagement teeth 268 preferably angle outwardly from bore 266 to facilitate reception of tapered nose 248 into bore 266 when synchronization cross - feed system 200 is in its engaged position where coupling assembly 212 mates with right coupling assembly 213 , as shown in fig1 . a bearing 270 of bearing assembly 210 of right coupling assembly 213 is disposed around fixed coupling 220 in a recess 272 therein and is received in a recess 274 in housing 209 . housing 209 includes a flange 276 secured to fixed element of thrust reverser 202 , such as a torque box 57 of the right side of the thrust reverser 202 , to secure right coupling assembly 213 in place . in operation , left coupling assembly 212 mates with right coupling assembly 213 when thrust reverser sleeves 28 are in their operational positions ( stowed or deployed ). in this regard , the right and left sides of thrust reverser 202 are in proximity to each other such that telescopic coupling shaft 214 has been urged into fixed coupling 220 such that engagement teeth 246 of left coupling assembly 212 engage engagement teeth 268 of right coupling assembly 213 . cylindrical shaft 250 of telescopic coupling shaft 214 is urged into synchronization shaft coupling 216 , compressing spring 262 , which urges telescopic coupling shaft 214 into fixed coupling 220 . telescopic coupling shaft 214 in cooperation with spring 262 allows for some movement between the halves of thrust reverser 202 without damaging synchronization cross - feed system 200 yet maintains the engagement of coupling assemblies 212 and 213 . further , since coupling assemblies 212 and 213 are held together only by the force of spring 262 , they decouple from each other when the left and right sides 203 , 205 of thrust reverser 202 are opened for maintenance , thus allowing the left and right sides 203 , 205 of thrust reverser 202 to be opened for maintenance . synchronization shafts 218 , 224 are coupled to translation actuators 54 of left and right sides of thrust reverser 202 in the same fashion as described above with reference to synchronization shaft 80 and translation actuators 54 and illustratively couples to a translation actuator 54 in lieu of manual drive clutch mechanism 96 , thus coupling to the synchronization system ( synchronization shaft 80 and associated components ) of the thrust reverser actuation system . in this regard , a manual drive mechanism , such as manual drive mechanism 300 ( fig1 ), would be added to thrust reverser 202 in place of manual drive clutch mechanism 96 . alternatively , manual drive clutch mechanism 96 would be appropriately modified to permit the respective synchronization shaft 218 , 224 to couple to the translation actuator 54 . in another embodiment , mechanical lock 104 would be appropriately modified to permit the respective synchronization shafts 218 , 224 to mate to mechanical lock 104 and thus to the synchronization system of the thrust reverser actuation system . with reference to fig1 , mechanical drive mechanism 300 has a housing 301 in which a spring loaded drive pin 302 is mounted . drive pin 302 has a square hole 304 in its top to receive a square driver . drive pin 302 has a bevel gear 306 at a lower end 308 ( as oriented in fig1 ). a shaft 310 extends transversely through housing 301 at a lower end 312 thereof . shaft 310 has a bevel gear 314 mounted thereon that mates with bevel gear 306 on drive pin 302 when drive pin 302 is depressed . a left end 316 ( as oriented in fig1 ) of shaft 310 is squared to mate with the double squared hole in a translation actuator , such as actuator 54 . left end 316 of shaft 310 could also be formed to have a double squared hole to mate with a shaft , such as synchronization shaft 218 or 224 , for “ in - line ” installation . a right end 318 of shaft 310 has a double squared hole to receive a squared end of a shaft , such as synchronization shaft 218 or synchronization shaft 224 . right end 318 of shaft 310 is affixed to cylindrical shaft 321 which is supported within housing 301 by a pair of bearings 322 . housing 301 further has attachment fittings 320 , such as b - nut fittings , surrounding left end 316 and right end 318 of shaft 310 . the description of the invention is merely exemplary in nature and , thus , variations that do not depart from the gist of the invention are intended to be within the scope of the invention . such variations are not to be regarded as a departure from the spirit and scope of the invention .