Ye olde enginemen
Printed From: Rontini Submarine BBS
Category: General
Forum Name: U.S. Submarine Related
Forum Description: Submarine Related Topics
URL: http://RontiniSubmarineBBS.com/forum_posts.asp?TID=4538
Printed Date: 24 Apr 2024 at 11:25pm
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Topic: Ye olde enginemen
Posted By: Runner485
Subject: Ye olde enginemen
Date Posted: 07 Apr 2018 at 11:32am
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I also put the same question on Gentry's BBS. Over the years, after I got out of the navy and began participating on these BBS's, I heard about "airless" starts of our engines, which were Fairbanks. Never having been involved in one of these evolution's, I am interested in finding in how to do one. I understand it has something to do with reversing the generators?? Has anyone been involved an airless start?  ------------- DBF Joe SS485,CVA42 Holland Club Mid-Atlantic Base |
Replies:
Posted By: Palm Bay Ken
Date Posted: 07 Apr 2018 at 2:14pm
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Been aboard for a few, but not back in maneuvering. As I recall, the OOD got us up to Standard on the battery and then ordered all stop. The controller men then did some magic with the sticks which caused the still turning shafts, which were still turning the motors, which then became generators to provide amps to motorize the generators which rolled the diesels. Probably not the best explanation, but it's all my 80 year old memory can recall. ------------- Ken Wiltshire K4HBE SS-206/SS-523/S1C/SSN-578/Ole Miss(NESEP)/DLG-14/SS-563/SS-567/SSN-584/CSS6/NavSafCen/ York County Public Schools/Virginia Beach City Public Schools/Retired |
Posted By: Runner485
Date Posted: 08 Apr 2018 at 8:15am
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Thanks Ken. I knew it had something to do with the generators that spun the engine, instead of the normal air process. ------------- DBF Joe SS485,CVA42 Holland Club Mid-Atlantic Base |
Posted By: oldsubs
Date Posted: 08 Apr 2018 at 12:48pm
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Same answer that I put on the other board If the air banks are depleted enough so engine air starting pressure/volume cannot be provided the engine must be started by an airless start. An airless start is done by energizing the generator as a motor to spin the engine for starting. The energizing voltage/current is supplied from one of three places. 1. The main motor spinning and acting as a generator. Boat comes up to some relatively fast speed. The motor lever is shifted to stop and the motor continues to spin driven by the screw moving through the water. 2. Another generator with a running engine. 3. The battery All three methods require interlocks being defeated/bypassed, for example the interlock that prevents a dead generator (not running) being attached to the motor bus. There are others. Defeating these interlocks is in direct violation of BuShips and/or NavSea instructions. Thus the operation needs Captains approval and he is liable to answer for the violation. I remember discussing and rehearsing the operation of airless starts and being asked as a Senior Controllerman qualification question to describe the procedure. However that was 50 years ago and that part of my mental notebooks seems to be deficient in details. I would refer a person who wants to figure it out to go to HNSA website, look in the fleet submarine manual, electrical section and wade through the interlock portion of the cubicle discussion. The airless start has been done and is possible however, the chance of killing a generator, motor, cubicle section or all three is not insignificant. Be Well Oldsubs |