The SAT HAT

 Copyright © by Gary L. Harris

The Sat Hat was originally designed and developed between 1976 to 1978 by Donald Rodocker and Chris DeLucci, two California commercial divers who founded the company Saturation Systems Inc. The Sat Hat was a very creative attempt to build a rugged, stainless steel dive hat whose focus was primarily saturation and mixed-gas (helium-oxygen) diving operations. The Sat Hat’s tooling was manufactured by John Clark of Ocean Products, a SCUBA equipment manufacturer, and the shell and components were constructed by the method of Investment-Casting. This is a process whereby a plug (mandrel) of meltable material, such as hard wax, is machined into the  desired shape. Then the wax plug is encased in ceramic, or other suitable material that can be broken. The wax is then melted out of the ceramic casement leaving behind a perfect mold of the original machined plug. Molten stainless steel is then poured into the ceramic mold and allowed to cool. The ceramic is then broken off the stainless steel and a helmet component of near perfect shape results. 

As one might guess, Investment-Casting is a very involved and expensive process, as a result so was the Sat Hat. On the other hand, Investment-Casting can create very complex metal shapes such as compound curves. Shapes that otherwise could only be manufactured in composite materials like glass fiber in resin, at least back in 1978.  Of course, this was in the days before Computer Aided Manufacturing  ( CAM ). Nowadays a computer, tied into a 3-D capable lath machine, would be used to create the same shape in metal; however, the cost is still very high for either process. Investment-Casting does still have its advantages over CAM in that it can make lighter, hollow metal components, which is very difficult for CAM .  

Rodocker and DeLucci built the Sat Hat to be highly versatile: a kind-of do-it-all approach. The helmet had a demand regulator, it also was equipped with a return line Push-Pull regulator for mixed-gas reclaim capability. In addition, the hat was capable of being used with a semi closed-circuit recirculator or even in an open circuit, free-flow mode. If the reader will look at the photos provided, he will see on the left side of the hat (port side) the demand regulator and a connector for closed-circuit operation (inlet port). On the right side is the check valve and push-pull attachment. Below that is the other recirculator/closed circuit connector, which would also double as an exhaust valve in demand or free-flow mode. The hat used an oral-nasal mask to limit carbon dioxide build-up in the respiration cavity (face area) during demand and closed circuit mode. The rubber mask also housed the microphone. The helmet’s head pad was a padded, sewn, nylon snoopy cap, not unlike that of the modern Superlite. Since the helmet was neutrally buoyant (in the demand mode), the tight fitting cap allowed the hat to move with the diver’s head; this negated the use of a jocking harness.    

The Sat Hat has a neck dam modeled directly from that of the Com Hat, which was originally designed by Mike Carson, who also now manufactures the stainless steel Carson dive hat (see: http://www.carsondivetech.com).  The pad on the top of the helmet shell is for the attachment of cameras and lights and the pad-eye on the back of the hat is for a small shackle. According to Donald Rodocker he and DeLucci borrowed a number of what they saw as good ideas from the Joe Savoie helmet and integrated them into the Sat Hat. For example, the Sat Hat has a stainless steel face port guard and an internal chin strap, similar to Joe’s hats. 

Additionally, the Sat Hat has a flip-up face visor, a concept also borrowed from the early Savoie helmets; a feature that would, in my opinion, turn out to have a minor affect on the way history sees the Savoie dive hat. Joe Savoie of Boutte , Louisiana USA was an Acadian (Cajun) of French heritage who invented the modern diving helmet back in 1963-64. He innovated the detachable neck dam (neck seal) principal, which is the seminal piece of technology that makes all modern dive hats possible. A debt is owed to the late Joe Savoie by all modern commercial divers and helmet manufacturers. 

Joe was a creative, complex, obstinate genius and he pioneered the way for the rest of us and freed following generations of professional divers to work more efficiently and safely.  Starting in 1964 Joe built twelve (he latter built a thirteenth in the 1990’s) early helmets that had a similar flip-up feature, latter borrowed by the Sat Hat’s designers. In the Saturation Systems catalog a diver was shown with the Sat Hat donned and with the flip-up visor in the raised position. The diver was holding a cup of coffee and smoking a cigarette. While this bit of advertisement did not create the myth that Joe Savoie incorporated a flip-up visor in his early helmets so a diver could sit on deck and smoke and drink coffee with his helmet on, it did help to perpetuate the fiction somewhat. In fact, Joe employed the flip-up feature for more complex reasons that had to do with the neck dam principal , but I will not go into that here.  Suffice it to note that I am presently searching for a publisher for my 4th book, titled: Cast A Deep Shadow: Joe Savoie, The Early Oil-Field Divers and The Invention Of The Modern Diving Helmet.  If the reader wants to know the answer to the above question, I suggest he purchase the book when it is available (Hey, I’m not above a shameless plug). 

A total of 36 Sat Hats were built. Of that number 18 were sold to Seaway Diving, now called COMEX-Stoltz, and the rest went to Taylor Diving and Salvage and Helinaut in the United States . The Sat Hats that were purchased by COMEX have the title: COMEX impressed into the top, front shell of the hat.  Donald  Rodocker was also the creator of the “Gas Miser” deep diving gas reclaim system. This is a helium-oxygen diver gas recovery system that takes expired gas from the diver’s helmet and passes it back up a return line, ganged to the diver’s umbilical. The gas is then cleansed of its carbon dioxide, small particulates and excess moisture. Oxygen is then added and the gas is pumped back down to the diver. The very creative Donald Rodocker still lives in California and continues to also be involved with remotely operated vehicle (ROV) design and manufacture.  

Gary Harris is a guest editor and frequent contributor to the Diving Heritage web site. He is a commercial diver and life support equipment designer of nearly three decades experience and an alumnus of the Ocean Corporation of Houston, Texas, BCC and the University of Central Florida. Mr. Harris has written for Underwater Magazine, Immersed, Spaceflight Magazine and Smithsonian Air and Space Magazine. In addition, he is the author of four books:  Ironsuit: The History of the Atmospheric Diving Suit, The Origins And Technology Of The Advanced Extravehicular Space Suit, An alternate View Of The Space Age and Cast a Deep Shadow: The Early Oil-Field Divers and the Invention of the Modern Diving Helmet. He lives near Cape Canaveral, Florida, USA.

Incoming free flow gas passed quietly through a silencer which directed the air flow across the face plate. This made communications very clear. The extra large lexan front plate allowed wide peripheral vision. A stainless steel protector prevented the face plate from beeing damaged or scratched.

Stainless steel SatHat with Comex decal. Photo courtesy: Magnus Lundbeck.