if reference is made to fig1 in the drawings , it will be noted that a fluid pressure operated launching system , in accordance with the teachings of the present invention , has been generally designated by the reference numeral 10 . in the present embodiment , the launching system 10 includes three hingedly connected elongated cylinder members designated by the reference numerals 12 , 14 and 16 . each of these cylinder members are provided with an opening in the form of a longitudinally disposed interior bore 18 as best seen in fig3 and 5 in the drawings . these cylinder members 12 , 14 and 16 may be of similar or varying lengths dependent primarily upon the requirements of a particular application or arrangement which will be better understood and appreciated as we progress . as is indicated and most apparent in fig1 the cylinder members 12 , 14 and 16 of the launching system 10 are readily portable and most compact in the folded position illustrated in solid lines . the total length t of the folded launching system 10 as shown in fig1 can be enlarged or diminished according to the desired compactness that could be dictated by the space allotted or available to accommodate the launching system 10 at a given site or on a particular transporting vehicle . in addition , the total extended length t 1 , the dotted line position in fig1 is usually determined by the acceleration and loading parameters that can be safely imposed upon the articles that are to be launched from the launching system 10 . as a consequence , required launch velocity , allowed acceleration and launcher length are inextricably tied together in accordance with the following : the launching system of the present invention may then be fabricated in any length required to meet the combination of imposed criteria in a given application . in this connection if reference is made to fig2 various positions on the curve can be translated to provide a relative indication of the required launcher length according to acceleration loads . in referring to this figure , it becomes obvious that the lower the tolerance of the article to be launched to acceleration loads , the greater the length requirement for the launching system . however , regardless of the required length of the launching system needed , compactness and ease of portability can readily be obtained by increasing either the number or length of the cylinder members 12 , 14 and 16 . in either case and as best seen in fig1 the cylinder members in a particular arrangement of the present launching system , however many in number or of whatever length as may be required , would be readily adaptable to be extended to the operative launching ( dotted line ) position having an extremely generous operating stroke while retaining its ability to assume a compact configuration for ease of portability and accommodation . the aforementioned interior bore 18 within each of the cylinder members 12 , 14 and 16 is of the same diameter in each of the respective hingedly connected cylinder members so that when the cylinder members are disposed in the open or launching mode corresponding to the dotted line position in fig1 the respective interior bore 18 in each of the individual cylinder members 12 , 14 and 16 will form a contiguous longitudinal opening or bore 18 that extends for substantially the entire length of the launching system 10 . as illustrated in the drawings and as best seen in fig3 longitudinal slot 20 is formed in the upper region of each of the cylinder members 12 , 14 and 16 and communicates with the interior bore 18 in each of the respective cylinder members 12 , 14 and 16 . a continuous , substantially flat metallic strip , hereinafter called a closure ribbon 22 is normally maintained under tension in a manner which will be more fully described as we progress , when the launching system 10 is in its operational launching mode . the closure ribbon 22 is adapted to cooperate with a bearing surface formed by a relieved portion 24 that is provided on each side of the aforementioned longitudinal slot 20 that communicates with the exterior of the cylinder members 12 , 14 and 16 and the interior bore 18 to provide a fluid tight seal between the contiguous interior bores 18 and the exterior of the cylinder member 12 , 14 and 16 . a piston assembly 26 best seen in fig5 & amp ; 6 includes a confined portion 28 , a web 30 and an extending or exterior portion 32 . web 30 extends through the slot 20 and holds the extending or exterior portion 32 integrally with the confined portion 28 of the piston assembly 26 . the aforementioned closure ribbon 22 extends into a cavity 34 that is provided within the confined portion 28 of the piston assembly 26 and is guided internally of the confined portion 28 by shoulders 36 and 38 having rounded surfaces that are in contact with the upper surface of the closure ribbon 22 . a pair of aligned flat surfaces 40 and 42 are provided in the confined portion 28 of the piston assembly 26 to further guide and bias the closure ribbon 22 against the aforementined bearing surfaces provided by the relieved portion 24 on each side of the longitudinal slot 20 . in this manner , a fluid tight seal between the internal bore 18 and slot 20 is established and maintained despite movement of the piston assembly 26 along cylinder member 12 , 14 and 16 , the shoulders 36 and 38 sliding along the top of the ribbon 22 to deflect and guide the closure ribbon through the piston assembly 26 during such movement . resilient cup seals 28a fastened to each end of the confined portion 28 of the piston assembly 26 prevent blowby past the confined portion 28 . the fluid pressure actuated launching system is operated in the conventional and well known manner . that is to say fluid pressure is introduced by the interior bore 18 where it is prevented from escaping through the slot 20 by the sealing engagement of the closure ribbon 22 with the relieved portion 24 . the fluid pressure is exerted against one side of the piston assembly 26 driving the piston assembly 26 and the article to be launched ( not shown ) which engages the projection provided on the exterior portion 32 . it should be noted that in the present embodiment , each of the aforementioned cylinder members are configured with a relatively flat , rail like upper surface which can be utilized to guide and / or support an aircraft or any other type of article ( not shown ) that is to be launched from the launching system 10 . as the piston assembly approximates the end of the stroke , suitable well known valving ( not shown ) may be employed to retard the piston and bring it to a halt as well as to pressurize the other side of the piston assembly 26 to return it to the start position for another operational cycle . it should be noted that an external pressure line ( not shown ) is often utilized as a conduit for the return fluid pressure and since operation of these fluid pressure actuated devices is well known to those skilled in the art , a further detailed discussion is not required herein . hinge means 44 connecting each of the aforementioned cylinder member 12 , 14 and 16 is shown in fig1 , 4 , 5 and 6 . it should be understood that in accordance with the teachings of the present invention , such hinge means would be utilized to operatively connect each cylinder member with an adjacent cylinder member so that in alternative embodiments wherein there may be fewer or a greater number of cylinder members employed , a correspondingly fewer or greater number of hinges 44 would be employed . however , since all of the hinge means employed would be identical , the foregoing detailed description of the hinge means connecting the cylinder members 12 and 14 will suffice with the understanding that an additional and identical hinge means 44 also connects cylinder members 14 and 16 in the present embodiment to facilitate mounting of the hinge means 44 , the cylinder member 12 is provided with hinge plates 46 , 46a and 46b which are fixed thereto by a plurality of bolts 48 that are threaded into the body of the cylinder member 12 in a conventional manner . the hinge plate 46 is provided with a protruding ear like member 50 which contains a journal ( not shown ) to receive a hinge pin 52 as best seen in fig3 and 4 . the member 50 also contains a threaded hole 54 that is coaxial to the interior bore 18 of the cylinder member and adapted to receive a retaining bolt 56 which serves to fasten and hold the adjacent cylinder members 12 and 14 in the operational launch mode as viewed in fig3 . hinge plates 46a and 46b are disposed respectively on the opposite side and underside of the cylinder member 12 and are similar and provided with bifurcated ear like protuberances 47 that are each adapted to accommodate one end of separate swing bolts 58 attached to the adjacent cylinder member 14 . similarly , the cylinder member 14 is provided with hinge plates 60 , 60a and 60b . hinge plate 60 is equipped with a bifurcated ear like protuberance 62 which straddles the aforementioned member 50 extending from the hinge plate 46 on the cylinder member 12 and accommodates the aforementioned hinge pin 52 to form the hinged connection between the cylinder members 12 and 14 . hinge plate 60a located on the opposite side of the cylinder member 14 relative to the hinge plate 60 and hinge plate 60b located on the underside of the cylinder member 14 are each equipped with bifurcated ear like protuberances 64 to each accommodate one end of the aforementioned swing bolts 58 . as will be noted in fig3 and 4 , each of the swing bolts 58 is received between the bifurcated protuberances 64 and pivotably secured thereto by a pivot pin 66 which passes through each of the protuberances 64 and the head of each swing bolt 58 . the opposite end of each swing bolt is equipped with a hex nut 58a threadably engaged with the swing bolt 58 such that when the hinged cylinder members 12 and 14 are brought into juxtaposition , the swing bolts 58 may be swung between the bifurcated protuberances 47 and the hex nut 58a tightened against the protuberance to firmly hold the cylinder members 12 and 14 in place . the aforementioned retaining bolt 56 in threaded engagement with the threaded hole 54 will assure that the cylinder members will be locked in place . in addition , adjacent cylinder members 12 and 14 and 16 may be equipped with a suitable alignment device such as the tapered alignment pin 68 shown fixed to the mating face of the cylinder member 14 and a correspondingly tapered apperture 68a provided on the mating face of the cylinder member 12 as best viewed in fig3 and 4 . such an arrangement assure that the longitudinal axis of each of the cylinder members 12 , 14 and 16 will coincide when the cylinder members are opened to the operational launch position despite any inaccuracies that may occur in the hinge means 44 either from reduced manufacturing tolerances , wear or excessive play between the hinge components . from our understanding of the invention thus far , it will be obvious that the hinged cylinder members 12 , 14 and 16 must have provision to relieve the tension of the closure ribbon 22 before the hinged cylinder members can be collapsed to form a compact readily transportable package . to facilitate this and permit the closure ribbon 22 to assume the position indicated in fig4 which incidentally has been exaggerated for greater clarity , a tensioning mechanism 70 shown in fig7 and 8 has been provided on one end block 71 of the launching system which is situated at one end of the cylinder member 12 . the closure ribbon 22 , while fixed at the end of the cylinder member 16 in a convenient fashion ( not shown ), is held under spring tension at the opposite furthermost extremity by the tensioning mechanism 70 . the closure ribbon 22 is fastened to the block 72 which is equipped with a spool handle 74 mounted to its upper surface . the block 72 is also provided with an offset leg 72a which is adapted to cooperate with a bearing block 76 to which it is fastened by a pin 78 which passes through a suitable aperture provided for the purpose in both the offset leg 72a and the bearing block 76 . the pin 78 is provided with an upper enlarged portion 78a the lower surface of which forms a shoulder that prevents the pin 78 from falling through the apertures in the leg 72a and bearing block 76 . a ring 78b fastened to the enlarged portion 78a permits the pin to be grasped for easy removal of the pin 78 from the apertures permitting the end of the closure ribbon 22 to become unrestrained . the bearing block 76 is adapted to slide along the upper surface of the end block 71 and is provided with an adjusting screw 76a which projects from the bearing block 76 in a direction opposite to the closure ribbon 22 . the adjusting screw passes through an aperture sufficiently large enough to permit free movement of the adjusting screw which is provided in a positioning member 80 . a compression spring 82 encircles the adjusting screw 76a and is disposed between the positioning member 80 and a seating washer 84 which is positioned axially on the adjusting screw 76a by means of nut threadably engaged with the end of the adjusting screw 76a . thus , the location of the nut on the adjusting screw 76a determines the compression force of the spring so that by rotating the nut one way or the other , the spring will be compressed or decompressed between it and the positioning member 80 thereby tensioning the closure means 22 operatively connected to the spring 82 in the manner described . to relieve the tension on the closure ribbon 22 , a toggle linkage 86 is fixed to the upper surface of the block 71 . the toggle linkage 86 is equipped with an actuating handle 88 which when moved to the dotted position shown in fig7 operates the positioning member 80 through associated linkage members that are yet to be described toward the closure ribbon 22 thereby unloading the compression spring 82 and permitting pin 78 to be removed by grasping and pulling the ring 78a and allowing the one end of the closure ribbon 22 to become unfettered . the aforementioned toggle linkage 86 is essentially what is commonly referred to as an over center linkage and is self locking to maintain the positioning member 80 in a fixed position relative to the end block 71 until the handle 88 is moved to the dotted position . as will be noted in fig8 the toggle linkage assembly is formed with a number of duplicate members spaced apart and arranged one above the other for better load distribution to a centrally located push pull member 89 that is located between them . however , the handle 88 has one end that is bifurcated and an offset bellcrank like portion 88b fastened by a suitable fastener 88c to one end of the push pull member 89 . handle 88 is pivotably connected by pin 88a to connecting links 90 . the connecting links 90 are pivotably mounted at their opposite ends on a pair of pins 92 which extend from the upper and lower surfaces of a fixed toggle link member 94 that is fastened to the upper surface of the end block 71 by a plurality of bolts 95 . push pull member 89 extends from the bellcrank end portion 88b to which it is fastened through a suitable bearing ( not shown ) provided in an upstanding portion of the fixed toggle member 94 and is received in a suitable aperture in the face of the positioning member 80 and is secured thereto by means of a bolt 98 which passes through the positioning member 80 and threadably engages push pull member 89 . thus , when the handle 88 is moved to the dotted position in fig7 the positioning block is moved in the direction of the closure ribbon 22 to the dotted line position shown in fig8 relieving the spring tension and permitting the closure ribbon to become unfettered and permitting the cylinder members to be collapsed . it is noted that the closure ribbon 22 will , when unfettered at one end , rotate approximately 90 ° on its own axis as shown in fig3 and bend transversely to the plane of its widest dimension . when the launch system 10 is to be restored to its operational condition , the closure ribbon 22 can be reconnected by grasping the spool handle and re - engaging the pin 78 whereafter the handle 88 can be restored to its over center locked ( full line ) position shown in fig7 by the previously described mechanism restoring the positioning member 80 and spring tension to the closure ribbon 22 . in summary , a brief recapitulation of the operational sequence to erect the launcher to its extended operational condition requires that the cylinder member 12 , 14 and 16 be released away from any constraints ( not shown ) that may have been used to hold the launching system 10 in its collapsed portable condition as shown in fig1 . the cylinder member 12 would then be rotated approximately 180 ° in the direction of the arrow in fig1 about the hinge means 44 and brought into juxtaposition with the cylinder member 14 . the tapered alignment pin 68 will engage the tapered aperture 68a on the mating surfaces of the cylinder members and assure the proper alignment of the cylinder members . the swing bolts 58 will be rotated into the bifurcated protuberances 47 and the hex nuts 58a rotated to tighten the bolts 58 against the surfaces of the protuberances 47 . retaining bolt 56 is then threadably engaged in the aperture 54 to lock the cylinder members 12 and 14 together . the same sequence is followed after the cylinder member 16 is rotated in the direction of the arrow in fig1 and brought into juxtaposition with the opposite end of the cylinder member 14 to lock all three of the cylinder members together in the operational launching position . the tension is then restored to the closure ribbon 22 by grasping the spool handle 74 drawing the spool and ribbon tight enough to align the apertures in the offset portion of the member 72a and bearing block 76 and inserting the locking pin 78 . the toggle linkage handle 88 is then moved to the solid line position as viewed in fig7 locking the positioning member 80 and restoring the preset spring tension furnished by the compression spring 82 to the closure ribbon 22 . to collapse the launching system 10 , the reverse order of sequence may be followed . although the invention has been described with reference to certain preferred embodiments , it will be understood that variations and modifications may be made within the spirit and scope of the invention as defined in the appended claims .