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Alan Gideon's avatar

I was part of the DDG-1000 (then DDGX) concept design team. No, that is not a confession, because we naval architects glued together all of the requirements placed before us - but it does give me a place at the table when discussing design risks. As a point of reference for those who have never designed a ship, please note that any addition or subtraction of an installed system or major change thereto can have ripple effects far out of proportion to the size, weight, power, manning, and cooling numbers advertised by that object/system’s proponent. In other words, advocate numbers never foreshadow what ship designers may be forced to do in order to shoehorn that additional toy into the toy box.

Shortly after being assigned to the Northrop-Grumman team, I showed my boss an interesting number. In addition to the known solid physics of existing hardware, we initially had 23 acknowledged technical risk areas. If a person is the ultimate optimist and assumes a success rate of 90% for each technical risk, the odds of all those risks not coming up as failures is calculated as 0.90 raised to the 23rd power. Your calculator will tell you those odds are a bit less than 9%. A whole 9% chance you won’t have to throw away your design and start over. If you had only six risks with that degree of optimism, you will just barely clear a 50-50 chance of redesign.

So we had that major redesign. And some of those risks turned into failures even after the redesign. And all of the redesign meant delay and additional cost. The Navy spent over $3B in RDT&E money in dealing with risk items and redesign, only to end up with a ship that can’t afford ammunition for its main guns. The Navy could decide to impose only 2, 3, or 4 sizable technical risks on a new design, but that would run afoul of all the system program offices that need to prove their relevance and all of the Congressional offices pushing something from their districts.

And all of this is separate from the mathematical flaws in DoD’s method of risk evaluation and measurement. But that is a discussion for another day.

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Ravi's avatar

Thank you for putting in words the unease I have been feeling for decades. I enjoy reading your thoughts and sharp observations

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