Jay wrote:
"......reflects poorly on the rest of the community, gets people killed, and tends to cause government to step in and regulate"
I should have been more clear about it but, this is precisely the point I was making. One of the things that has chased me from the sky (costs aside) is overregulation. My point about ABS and Lloyds was that they are obligatory for commercial ops whereas the homebuilder is absolutely free to pursue whatever he wishes without hindrance or oversight. This is both a blessing and a potential curse as you pointed out and is where people like yourself and Hugo can have the most impact, which is what I was saying.
The hatch story was both interesting and informative...thank you. In the future, I will attempt to be more to the point.
Joe
From: "Jay K. Jeffries" <bottomgun@mindspring.com>
Reply-To: personal_submersibles@psubs.org
To: <personal_submersibles@psubs.org>
Subject: RE: [PSUBS-MAILIST] Safety Concerns
Date: Wed, 4 Jan 2006 22:08:14 -0500
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Joe and others here,
I have been reading this forum for many years and have to agree with Hugo as to his concern that safety is taking second place to ingenuity and cost in many recent posts. History has made successful submarine designer and operators very conservative and cautious. Billy Deans, a friend and early innovator in technical diving, once said ?Sheer stupidity is self correcting?. Unfortunately sheer stupidity (even minor stupidity) reflects poorly on the rest of the community, gets people killed, and tends to cause government to step in and regulate.
Joe, your corollary is well founded when looking at the aviation community but the submarine operational environment is much less forgiving. I agree with you that while there are NTSB reports for aircraft incidents, there is no one source for submersible incidents. By shear numbers the aviation community is far larger than submariners and thus will have a much better communication network (also probably a higher incident rate per 1000 hours of operation because the threshold for entry into the aviation community is much easier). You separate out ABS and Lloyds (and der Norske Veritas SP??) from the PSUB community since these were supposedly developed for commercial applications. While this is true, the hard lessons learned to form these standards came from many previous hours of experimentation and operation in research and military subs?common lessons that apply to any submarine or submersible. While some of the standards may appear over restrictive, previous experience dictated this approach.
A good example is how a sub hatch opens. You will find that all US Navy sub hatches open to either the side or forward (not back as found on most PSUBs). The reason for this stems from some of the first experiences of John Holland while experimenting on his early prototypes (which were the size of many current day PSUBs). When he was first underway with some headway on the surface in open water, he encountered some moderate seas as he was navigating with his head out of the hatch on a sub with little freeboard. When he ducked down and attempted to close the hatch, the on-rushing water almost didn?t allow him to close the hatch as the sub was forced down by the additional unintentional ballast. After great effort the hatch was closed and a considerable amount of water had to be pumped from the bilges to regain control of buoyancy. If he wasn?t so lucky, the world of submarines might be completely different today (my great-great uncle Simon Lake might have prevailed J ). From that point on, hatch closure configuration was changed to avoid a similar situation.
The fatalities that have occurred throughout the history of submarines can be narrowed down to a few areas. This would be a good topic for conversation as it gets you to always think of contingency planning in your design and operation.
1. Failure of materials (Thresher and many others).
2. Failure of design (torpedo door interlocks numerous times, rather specific to military submarines but applicable to any sub with a lock-out capability).
3. Poor or no contingency plan (Johnson Sea-Link).
4. Operator error (S-5 main exhaust vent closure (also design issue), M-1 or 2 with their hanger hatch open (reserve buoyancy issue also), almost all of the steam-powered K-boats).
5. Delaying relief operations from within or without (Squalus, Thetis, Kursk, and almost the recent Russian submersible).
6. Inadequate reserve buoyancy (Alvin, Cousteau saucer, tourist sub supposedly under tow up from Mexico?may have been insurance fraud though, and nuke boat (Greenling ??) under construction at the pier at Mare Is. NSY?name escapes me currently).
7. Sea-air interaction (Greenville and many others while collisions while surfacing?this is the reason for the port in the hatch to be able to look up while ascending. Also included in this is the great hazard of launch and recovery of a small submersible).
While many of these are related to military submarines, the issues are still common throughout the submarine community as we all operate in the same environment and experience many of the same issues (other than nuclear power but I hear there is a mod in for the Euronaut to add a module at a later date J).
If memory serves me correctly (my submarine library is not in front of me right now as I am vacationing in the frigid, grey North just a few miles from a PSUB that was recently up for bid on eBay probably due to stability issues), MIT Sea Grants Office published a lengthy report in the late 70?s on submarine/submersible failure modes. In addition, a NOAA or NTSB report on then rapidly expanding tourist sub industry reported on possible modes of failure and mitigation.
It might first be better to ask why something is designed or done a certain way on submarines so that a firm base of understanding is built. This will better support the making of design or operational decisions that may not have obvious safety consequences.
Guess I have been on my soap box long enough.
Respectfully,
Jay K. Jeffries
One in a long line of submariners
Holder of a set of K-250 plans since 1976
Andros Island, Bahamas
Hugo wrote:
"It distresses me greatly when I feel that safety is given a second place ahead of cost and ingenuity, and I would hate to see any Psubber involved in a fatal accident."
I can't help but see another parallel to aviation here in terms of safety. In the course of my research for this project, I've come across relatively few fatal accidents among the amateur built submersible community. I attribute this to two things, local reporting which is lost to a wider audience, and a relatively small amateur submersible community.
The PSUBS website lists two tragedies. One involving JSL (hardly an amateur project) and an amateur prototype which was apparently planned for production, and resulted in a fatality during testing.
My point is that there are literally tens of thousands of homebuilt aircraft both flying and being built. There are thousands of accident reports and one can learn from the online NTSB reports from another's mistake or misfortune. There is no such body for this group, the amateur or homebuilt psub. ABS and Lloyds standards are designed for commercial applications. There is no FAA watching over us. As a pilot, I am lost in a sea of pilots.
What you have here is a unique opportunity for a relatively small group of people to help keep one another out of trouble so long as ego does not interfere. There are people here with truly impressive credentials and others with equally impressive success stories.
From time to time, I have sensed a degree of frustration among those most experienced, with those of us less so. To you I say, keep at it because anyone who pilots, builds or just "thinks" about personal submersible, is a member of a small unique fraternity. Really small!
Joe P