How many licks..
Join Date: Mar 2004
In the garage:
Totally awesome. Man, they can put cameras anywhere now.
I always forget that someone has to go out and retrieve the SRB's from the ocean each launch...
11,000 LBS of fuel burned each second... that's like burning 3.1 of my cars each second.
At the start of the vid, when they mention the sound supression water system...
MLP = Mobile Launcher Platform.
When NASA began launching shuttle missions, it became clear that the MLP might inadvertently pose a danger to the crew or the vehicle: massive acoustic shock waves and rocket exhaust can bounce off the platform and hit the shuttle as it lifts off. This was true for the Saturn V launches as well, but there was less risk because the Apollo Modules, atop the 363-foot (111 m) stack, were so much further away from the engines. Because the shuttle is about half the height of the Saturn, the crew-cabin and payload bay are much closer to the platform and much more vulnerable to the tremendous forces bouncing back off the MLP - on the first mission, STS-1, the shock waves damaged much of the protective thermal tiles.
NASA's solution to this danger is to cushion the MLP at every launch with a flood of flowing water. Starting 6.6 seconds before engine ignition, a 300,000-gallon water tank at the launch site begins dumping water down a pipeline and into the exhaust vents of the MLP. Next, six 12-foot (3.7 m)-high towers known as "rainbirds" begin to spray water over the MLP and into the flame deflector trenches below it. The water absorbs some of the bruising forces of the acoustic waves, and discourages fires that might be caused by the rocket exhaust. This water-dumping mechanism, known as the Sound Suppression System, empties the launch pad tank in around 41 seconds. The giant white clouds that billow around the shuttle at each launch are not smoke, but steam generated as the rocket exhaust boils away huge quantities of water. The suppression system reduces the acoustic sound level to approx 142 dB.
What happens to the SRBs during their return:
Descent and recovery
The solid rocket boosters, jettisoned from the Space Shuttle Discovery following the launch of STS-116, floating in the Atlantic Ocean about 150 miles north east of Cape Canaveral.
A command is sent from the orbiter to the SRB just before separation to apply battery power to the recovery logic network. A second, simultaneous command arms the three nose cap thrusters (for deploying the pilot and drogue parachutes), the frustum ring detonator (for main parachute deployment), and the main parachute disconnect ordinance.
The recovery sequence begins with the operation of the high-altitude baroswitch, which triggers the pyrotechnic nose cap thrusters. This ejects the nose cap, which deploys the pilot parachute. Nose cap separation occurs at a nominal altitude of 15,704 ft (4,787 m), about 218 seconds after SRB separation. The 11.5 ft (3.5 m) diameter conical ribbon pilot parachute provides the force to pull lanyards attached to cut knives, which cut the loop securing the drogue retention straps. This allows the pilot chute to pull the drogue pack from the SRB, causing the drogue suspension lines to deploy from their stored position. At full extension of the twelve 105 ft (32 m) suspension lines, the drogue deployment bag is stripped away from the canopy, and the 54 ft (16 m) diameter conical ribbon drogue parachute inflates to its initial reefed condition. The drogue disreefs twice after specified time delays (using redundant 7 and 12-second reefing line cutters), and it reorients/stabilizes the SRB for main chute deployment. The drogue parachute has a design load of approximately 315,000 lb (143,000 kg) and weighs approximately 1,200 lb (540 kg).
After the drogue chute has stabilized the SRB in a tail-first attitude, the frustum is separated from the forward skirt by a pyrotechnic charge triggered by the low-altitude baroswitch at a nominal altitude of 5,500 ft (1,700 m) about 243 seconds after SRB separation. The frustum is then pulled away from the SRB by the drogue chute. The main chute suspension lines are pulled out from deployment bags that remain in the frustum. At full extension of the lines, which are 203 ft (62 m) long, the three main chutes are pulled from their deployment bags and inflate to their first reefed condition. The frustum and drogue parachute continue on a separate trajectory to splashdown. After specified time delays (using redundant 10 and 17-second reefing line cutters), the main chute reefing lines are cut and the chutes inflate to their second reefed and full open configurations. The main chute cluster decelerates the SRB to terminal conditions. Each of the 136 ft (41 m) diameter, 20-degree conical ribbon parachutes have a design load of approximately 195,000 lb (88,000 kg) and each weighs approximately 2,180 lb (990 kg). These chutes are the largest that have ever been used — both in deployed size and load weight. The RSRM nozzle extension is severed by a pyrotechnic charge about 20 seconds after frustum separation.
Water impact occurs about 279 seconds after SRB separation at a nominal velocity of 76 feet per second (23 m/s). The water impact range is approximately 130 nmi (240 km) off the eastern coast of Florida. Because the parachutes provide for a nozzle-first impact, air is trapped in the empty (burned out) motor casing, causing the booster to float with the forward end approximately 30 feet (9.1 m) out of the water.
Solid rocket booster of the STS-114 mission being recovered and transported to Cape Canaveral.
Formerly, the main chutes were released from the SRB at impact using a parachute release nut ordnance system (residual loads in the main chutes would deploy the parachute attach fittings with floats tethered to each fitting). The current design keeps the main chutes attached during water impact (initial impact and slapdown). Salt Water Activated Release (SWAR) devices are now incorporated into the main chute riser lines to simplify recovery efforts and reduce damage to the SRB. The drogue deployment bag/pilot parachutes, drogue parachutes and frustums, each main chute, and the SRBs are buoyant and are recovered.
Specially fitted NASA recovery ships, the Freedom Star and the Liberty Star, recover the SRBs and descent/recovery hardware. Once the boosters are located, the Diver Operated Plug (DOP) is maneuvered by divers into place to plug the SRB nozzle and dewater the motor case. Dewatering, pumping air into and water out of the SRB, causes the SRB to change from a nose-up floating position to a horizontal attitude more suitable for towing. The retrieval vessels then tow the boosters and other objects recovered back to Kennedy Space Center.
97' M3. '10 R6.