The inverse operation is easily performed however, and absolutely no
precision exports are required :-). Simply:
1. Open the throttle too fast, even on a "non-cavitation" screw
2. Run over a log while exiting port
3. Bump the sill of the floating dry-dock on the way out
4. Back into the divers' barge
The submarine I was on rarely did number 1 (and no throttle-man ever did it
twice, let me tell ya) but did 2-4 all in the space of about 6 months.
Computer milling of a blank of phosphor-bronze of the appropriate diameter
and thickness for an SSN's screw ain't cheap...
I was told that a 1/32" broad x 1/32" deep by 6 inch scratch was enough to
render our screw effectively worthless. It would "sing" due to cavitation
along the scratch even under normal, non-cavitating use.
---
Scott Gomez
-----Original Message-----
From: Gary Edwards [mailto:garyetx@xxxxxxxxx]
Subject: Re: [OM] OT Low Flying, was an OM weekend
<snip>
The big flap a dozen years ago over Toshiba's illegal sale of computer
controlled milling machines to the Soviet Union was based on the fact that
that technology allowed them to better build complex, non-cavitating (thus
quieter) submarine screws.
Gary Edwards
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