the parachute opens, shortly after departing 

 the aircraft. It cuts the parachute free about 

 20-30 feet above the water surface, allowing 

 the box to free-fall to the surface. This mini- 

 mizes the opportunity for the parachute to fall 

 on the box and interfere with the buoy self- 

 deployment process, an event that did occur 

 when the 2 m spar buoys were launched, 

 albeit infrequently. 



The second cutter, whose pin is pulled 

 when the parachute cuts free, cuts a stainless 

 steel cable that holds the straps together. This 

 is also a 1 0-second cutter, thus the straps are 

 cut free 10 seconds after the parachute cuts 

 free. Even if the parachute cuts free after 

 splashdown, the parachute will collapse into 

 the water and the differential movement of the 

 box and the parachute will pull the pin of the 

 second cutter. Once the straps are cut, the 

 plywood sides fall away, exposing the card- 

 board box to the water. If both cutters fail, the 

 two straps holding the plywood box together 

 will come apart. Each strap has loop with a salt 

 tablet, arranged so that the loop will pull out of 

 a metal buckle when the salt dissolves. 



The parachutes used in the testing of 

 the drop package were 28-foot personnel para- 

 chutes. These parachutes, which can easily 

 take the weight of the package, were obtained 

 free-of-charge (unpacked) because they had 

 exceeded their useful life for personnel drops. 

 When the parachutes were packed, the 

 shrouds were cinched up to increase the de- 

 scent rate. This issue is discussed in detail in 

 Taylor and Murphy, 1992. 



Detailed instructions for the fabrication 

 of the entire drop package are presented in 

 Taylor and Murphy, 1992. 



Two separate tests were conducted 

 underthe supervision of the STAN Team. The 

 tests had two goals: first, to ensure that the 

 buoy could be safely and successfully launched 

 from the HC-130 and, second, to ensure that 

 the buoy would self-deploy from its air-deploy- 

 ment package after entry into the water. In 



both tests, an aircraft and a surface vessel 

 participated. The air-deployment and the sub- 

 sequent self-deployment of the buoy were 

 recorded on video tape. The buoys used in the 

 test drops were manufactured by MetOcean 

 DataSystems, Inc. of Dartmouth, Nova Scotia, 

 Canada. 



During the first test, the parachute de- 

 ployed and cut free as designed, however, 

 there were two problems. First, afterthebuoy 

 package left the ramp, it flew up towards (but 

 did not hit) the tail of the airplane. Second, the 

 cardboard box which contains the buoy floated 

 too high on the surface for much of the water 

 soluble tape to be wetted. After three hours in 

 one meter seas, the buoy had not deployed 

 out of the box. Both problems were solved 

 with minor modifications. The first was solved 

 by adding about 50 pounds of additional weight 

 to the drop package. (A Nansen bottle box 

 filled with sand was screwed to the inside of 

 the box.) This increased the weight of the air- 

 deployment package to about 250 pounds, 

 which is still within the weight capability of the 

 28-foot parachute. The second problem was 

 solved by cutting the top and the corners of the 

 cardboard box, allowing the box to open as 

 soon as the plywood falls away. 



The modifications were tested during a 

 second airdrop test, which was completely 

 successful. The package departed the aircraft 

 cleanly and without flying upward, the two 

 reefing line cutters functioned as planned, and 

 the buoy deployed out of the cardboard box in 

 a matter of minutes. 



The parachutes used in the operational 

 air-deployment system are 28-foot cargo para- 

 chutes, which are purchased through the Fed- 

 eral Stock System for about $65. They are 

 equivalent to the parachutes used in the two 

 tests. The cost of the entire air-deployment 

 package, including the box, is about $400, 

 with most of the cost in the parachute and the 

 reefing line cutters. The box is constructed as 

 a shipping container by the buoy manufac- 



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