44 the modular system 8 described above has a number of advantages the elements of the modular system 8 for example are fastened together in a manner that permits easy removal of at least one of the front end cap 14 and rear end cap 18 for pre flight ground processing of cargo and equipment individual cylinder body sections 10 can also be easily preloaded prior to integrating the complete modular system 8 as illustrated in fig7 the use of the external tendon array assembly 18 also permits full utilization of interior volume of the integrated modular system so that standardized equipment racks can be located completely around the circumference of the cylinder body sections 10 further the use of the flexible pressure seals 12 between cylinder sections 10 allow the nsts orbiter to flex without coupled loading thereby reducing stress on the modular system 8 and the nsts orbiter during launch and flight still further one or more of the modular systems 8 can be loaded within the cargo bay of the nsts orbiter either alone or in combination with other payloads as illustrated in fig8 10 the invention has been described with reference to certain preferred embodiments thereof it will be understood however that modifications and variations are possible within the scope of the appended claims for example in applications where flexibility is not required of the modular system 8 the flexible pressure seals 12 between cylindrical sections 10 can be eliminated and the flanges 44 of the cylindrical sections 10 can be directly coupled together with a gasket to provide sealing the elimination of the flexible pressure seals 12 will also reduce the length of the modular system 8 the overall length of the modular.