swimmer2 said:I see no one has been on this thresd for about a year, so I'll stop now to see if anyone is interested in anything else about the SES100A.
Especially anything about the follow on concepts for the 100 knot navy
tsmero said:like i said, some good pictures and lot of XR1 sinking and being towed back eventually by our chase boat which was a big bertram and a luhrs.
I worked on the SES 100A from 1968-1971 at the El Monte facility for Aerojet. I was a liaison engineer with Dr. Richard Wade and would take his hydrodynamic formulas and create drawings that our experimental machinists, Pete and Dave, would then create 1/32 scale models that we would then take to Cal Tech and run in their water tunnel. We also created a 1/8 scale model of the ship to test in the David Taylor Model Basin in Carderock, Maryland. I also worked on the Data Acquisition System, the on board computer, that took a reading of over 100 transducers every 1/10 of a second on the test runs. It's strange that In two different articles, one in Encyclopedia Brittanica that never mentioned the SES 100 and another from Wikipedia on Suerface Effect Ships that never mentioned Aerojet.Wow! I was informed of this thread by swimmer1. He and I worked for Aerojet back in 1973-4 as scuba divers in Sitcum Waterway in Tacoma, Washington. I was 18, then turned 19 during this time. We had many adventures, from spending literally hundreds of hours working on rigging and air bags under the testcraft, to training missions, to finding parts dropped off the pier by our august band of technicians. We even got to jump out of a helicopter into the Straits of Juan De Fuca during a storm when the testcraft hit a log at about 40 knots with a bunch of senators and high ranking Navy personnel on board, using long screwdrivers to pry out splinters of wood that were restricting intake flow of water for the waterjets. We received letters of commendation for that, a write up in the company newspaper and free beer. Did I mention I was I was 19? Probably the best and most adventurous job any young man could have, Aerojet treated us both right in retrospect. The photos in the thread are interesting, the ones with the raised covers over the engine bays are later than the one with no covers. Also, this was a 100 ton craft, built in Tacoma, WA, at Tacoma Boatbuilding Co., long since deceased. The 100B was built in Louisiana by Bell Aircraft, utilizing some different technologies to see which was more efficient. These ships were going to be the precursors to the 100 knot Navy, but got smacked in the teeth by the first gas crisis during the time I was there.
The 100A utilized thin catamaran type sidewalls to provide stability as it ran through the water. There was a "bow seal" (seen in black in the photos) on the front to contain air pumped under the vessel to provide lift, then tilt back underneath as it hit waves to reduce drag. In the stern was a similar rubber membrane wall which performed the same function as the bow seal, with the difference that it had several adjustible sheets of aluminum to provide strength and prevent blowout of the cushioning air. This could be tilted to raise or lower the stern seal as a means to trim the ship. Visible on the photos, on the surface about 3/4 of the way back, are louvers, connected to barometric sensors, located under the hull, to direct these louvers to open and close as waves ran under the craft and thereby mitigating displacement of the air cushion. In this way, porpoising of the testcraft was reduced, providing a very smooth ride, and allowing speeds of up to 100+ knots.
Also visible on the cut away view, in the lower corner, is shown the portside engine room, where I began my adventure with Aerojet as an oil wiper. These spaces were inspected before every test run, literally with white gloves (this is TRUE!), to make sure nothing was ingested by the motors. We used to crawl around on these damn things while they were running occasionally, and subsequently, I'm a bit deaf today. OSHA didn't exist back then.
I see no one has been on this thresd for about a year, so I'll stop now to see if anyone is interested in anything else about the SES100A.
Just found this thread as I research my Grandfather’s past at Aerojet. His name is Robert Thomson and moved to Tacoma as an engineer for Aerojet and retells the fun he had working on the SES100A.Wow! I was informed of this thread by swimmer1. He and I worked for Aerojet back in 1973-4 as scuba divers in Sitcum Waterway in Tacoma, Washington. I was 18, then turned 19 during this time. We had many adventures, from spending literally hundreds of hours working on rigging and air bags under the testcraft, to training missions, to finding parts dropped off the pier by our august band of technicians. We even got to jump out of a helicopter into the Straits of Juan De Fuca during a storm when the testcraft hit a log at about 40 knots with a bunch of senators and high ranking Navy personnel on board, using long screwdrivers to pry out splinters of wood that were restricting intake flow of water for the waterjets. We received letters of commendation for that, a write up in the company newspaper and free beer. Did I mention I was I was 19? Probably the best and most adventurous job any young man could have, Aerojet treated us both right in retrospect. The photos in the thread are interesting, the ones with the raised covers over the engine bays are later than the one with no covers. Also, this was a 100 ton craft, built in Tacoma, WA, at Tacoma Boatbuilding Co., long since deceased. The 100B was built in Louisiana by Bell Aircraft, utilizing some different technologies to see which was more efficient. These ships were going to be the precursors to the 100 knot Navy, but got smacked in the teeth by the first gas crisis during the time I was there.
The 100A utilized thin catamaran type sidewalls to provide stability as it ran through the water. There was a "bow seal" (seen in black in the photos) on the front to contain air pumped under the vessel to provide lift, then tilt back underneath as it hit waves to reduce drag. In the stern was a similar rubber membrane wall which performed the same function as the bow seal, with the difference that it had several adjustible sheets of aluminum to provide strength and prevent blowout of the cushioning air. This could be tilted to raise or lower the stern seal as a means to trim the ship. Visible on the photos, on the surface about 3/4 of the way back, are louvers, connected to barometric sensors, located under the hull, to direct these louvers to open and close as waves ran under the craft and thereby mitigating displacement of the air cushion. In this way, porpoising of the testcraft was reduced, providing a very smooth ride, and allowing speeds of up to 100+ knots.
Also visible on the cut away view, in the lower corner, is shown the portside engine room, where I began my adventure with Aerojet as an oil wiper. These spaces were inspected before every test run, literally with white gloves (this is TRUE!), to make sure nothing was ingested by the motors. We used to crawl around on these damn things while they were running occasionally, and subsequently, I'm a bit deaf today. OSHA didn't exist back then.
I see no one has been on this thresd for about a year, so I'll stop now to see if anyone is interested in anything else about the SES100A.
Nice cutaway of the 100B. That vessel utilized rather thick, planing hulls in a catamaran type configuration with the front and rear seals to contain air to provide lift. The flat bottom of those hulls was to provide a planing surface to see if it, instead of the knife edge hulls of the 100A, was faster, and also to determine if they helped increase load bearing abilities. Also, instead of steerable nozzle water jets, the 100B used twin propellers, rather in the shape of a sunflower, that were designed to supply thrust while only half submerged, without cavitation.
I believe the 100A was faster. I don't know about load carrying differences, if any.
Someone asked if there were any follow on designs for this technology, and in Tacoma, there are two fireboats using the knife edged SES configuration to this day, along with the waterjets for propulsion. The downside was that their building was outsourced to England, rather than being built in this area, utilizing some of the excellent skilled craftsmen who were still of working age at that time. These fireboats are roughly 50-60 feet long, whereas the 100A was 40 fett wide by 80 feet long. These craft are also fiberglass in construction, rather than aluminum. They are yellow. But I'm not sure if that affects function or not :0)
I'm lobbying to get swimmer1 to blog and post some excellent photos of the testcraft from back in the day, along with some shots of the capazons and octopi we caught and ate during our travels up and down Puget Sound.
Anyway this post is really old so I doubt anyone will notice my little addition
I remember Bob - I hung out with the engineers more than the work crews as my dad was the head of the SES QA department in Rancho Cordova and Tacoma. I blew my knee out in late 1973 so I missed the last of the tests but I was there when the boat became a submarine....Just found this thread as I research my Grandfather’s past at Aerojet. His name is Robert Thomson and moved to Tacoma as an engineer for Aerojet and retells the fun he had working on the SES100A.