# How do you start a BIG engine? **URL:** \ **Category:** Factual Questions\ **Created:** [September 8, 2009, 4:09pm UTC](https://boards.straightdope.com/t/how-do-you-start-a-big-engine/509299 "2009-09-08T16:09:13Z")\ **Posts on this page:** 11\ **Page:** 3
**Author:** ![Princhester](https://avatars.discourse-cdn.com/v4/letter/p/3e96dc/32.png) [@Princhester](https://boards.straightdope.com/u/Princhester)\ **Post date:** [September 10, 2009, 11:13am UTC](https://boards.straightdope.com/t/how-do-you-start-a-big-engine/509299/41 "2009-09-10T11:13:53Z")
> [@Snnipe\_70E](#): > > A cruise ship needs mobilty. with AZIPODS and bow thrusters a cruise ship can do turn end for end. a freighter or tanker does not need to make those kinds of turns. Yes they do. Swinging such vessels is commonplace. In the vast majority of ports of which I have experience, you can’t go out the same way you came in. Because it is easier to swing a vessel in ballast (rather than loaded) ships come into the loadport, swing head down and berth, then load and depart, and do the opposite at the disport. ---
**Author:** ![Cicero](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/cicero/32/3594_2.png) [@Cicero](https://boards.straightdope.com/u/Cicero)\ **Post date:** [September 10, 2009, 11:41am UTC](https://boards.straightdope.com/t/how-do-you-start-a-big-engine/509299/42 "2009-09-10T11:41:59Z")
So how do they start a nuclear powered aircraft carrier? ---
**Author:** ![Princhester](https://avatars.discourse-cdn.com/v4/letter/p/3e96dc/32.png) [@Princhester](https://boards.straightdope.com/u/Princhester)\ **Post date:** [September 10, 2009, 11:51am UTC](https://boards.straightdope.com/t/how-do-you-start-a-big-engine/509299/43 "2009-09-10T11:51:35Z")
Very very carefully ---
**Author:** ![Cicero](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/cicero/32/3594_2.png) [@Cicero](https://boards.straightdope.com/u/Cicero)\ **Post date:** [September 10, 2009, 12:01pm UTC](https://boards.straightdope.com/t/how-do-you-start-a-big-engine/509299/44 "2009-09-10T12:01:35Z")
I was fission for an answer. ---
**Author:** ![Rocketeer](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/rocketeer/32/4437_2.png) [@Rocketeer](https://boards.straightdope.com/u/Rocketeer)\ **Post date:** [September 10, 2009, 3:18pm UTC](https://boards.straightdope.com/t/how-do-you-start-a-big-engine/509299/45 "2009-09-10T15:18:37Z")
…moan… ---
**Author:** ![Pushkin](https://avatars.discourse-cdn.com/v4/letter/p/ee59a6/32.png) [@Pushkin](https://boards.straightdope.com/u/Pushkin)\ **Post date:** [September 10, 2009, 3:56pm UTC](https://boards.straightdope.com/t/how-do-you-start-a-big-engine/509299/46 "2009-09-10T15:56:44Z")
> [@Cicero](#): > > So how do they start a nuclear powered aircraft carrier? I’m curious, is there a big starter button in engineering/the bridge on any ship? Something that would make a land lubber like me think “Ah, so simple”. ---
**Author:** ![Whack-a-Mole](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/whack-a-mole/32/141_2.png) [@Whack-a-Mole](https://boards.straightdope.com/u/Whack-a-Mole)\ **Post date:** [September 10, 2009, 5:07pm UTC](https://boards.straightdope.com/t/how-do-you-start-a-big-engine/509299/47 "2009-09-10T17:07:01Z")
> [@Cicero](#): > > So how do they start a nuclear powered aircraft carrier? > [@Pushkin](#): > > I’m curious, is there a big starter button in engineering/the bridge on any ship? Something that would make a land lubber like me think “Ah, so simple”. Well, there is the initial start of the reactor but once running I think it is always running to some extent till it needs to be refueled. I certainly do not know the ins-and-outs of reactor startup but I imagine it involves putting the fuel in and moving the control rods which slow the reaction enough to allow fission to start. Pretty sure fission will start naturally in the reactor with the fuel in proximity to each other like that. No doubt a lot of things need to be happening parallel with this (coolant pumps running and so on). Doubtless there is more than a button push but perhaps it is that simple with a computer running things (and humans closely monitoring to make sure all goes as planned). After that the nuclear reactor is really just a fancy way to boil water to make steam to turn turbines. Want the ship to go I guess you increase the reaction in the reactor and start boiling more and more water. Build up pressure, get the turbines spinning and away you go. ---
**Author:** ![Princhester](https://avatars.discourse-cdn.com/v4/letter/p/3e96dc/32.png) [@Princhester](https://boards.straightdope.com/u/Princhester)\ **Post date:** [September 11, 2009, 3:53am UTC](https://boards.straightdope.com/t/how-do-you-start-a-big-engine/509299/48 "2009-09-11T03:53:10Z")
> [@Pushkin](#): > > I’m curious, is there a big starter button in engineering/the bridge on any ship? Something that would make a land lubber like me think “Ah, so simple”. There is a lot of variety but generally speaking no. The big diesels used on commercial vessels are started by the engineers from the engine room, and there are a series of steps to go through involving turning on various pumps, closing this, opening that, before you can start it. ---
**Author:** ![Snnipe\_70E](https://avatars.discourse-cdn.com/v4/letter/s/b5a626/32.png) [@Snnipe\_70E](https://boards.straightdope.com/u/Snnipe_70E)\ **Post date:** [September 11, 2009, 4:10am UTC](https://boards.straightdope.com/t/how-do-you-start-a-big-engine/509299/49 "2009-09-11T04:10:49Z")
The captian tells the Chief Engineer when he wants to leave port. If the Chief agrees he will inform the engineering watch officer when to be ready to answer bells. The closest thingf to a start button is the EOT (engine order telegraph). The bridge will ring up stand-by engines as they single up lines. ---
**Author:** ![Oslo\_Ostragoth](https://avatars.discourse-cdn.com/v4/letter/o/a9a28c/32.png) [@Oslo\_Ostragoth](https://boards.straightdope.com/u/Oslo_Ostragoth)\ **Post date:** [September 13, 2009, 4:59am UTC](https://boards.straightdope.com/t/how-do-you-start-a-big-engine/509299/50 "2009-09-13T04:59:28Z")
> [@Deereman](#): > > Small gasoline engines were used to crank over hard starting large diesel engines, back when the electric starters weren’t up to snuff. > > They’re usually called pony starts, donkey engines, or cranking engines and were used on John Deere diesel tractors from 1949-1960. Tiny opposed two cylinder engines or tiny V4s, depending on the tractor. > > And on Caterpillars too, as was mentioned > > Here is a video of a pony start Deere, being started: > [Photo Storage](http://s108.photobucket.com/albums/n8/weirddeere/?action=view¤t=70DStart.flv) A Johnny Popper? (Two cylinders opposed?) ---
**Author:** ![Oslo\_Ostragoth](https://avatars.discourse-cdn.com/v4/letter/o/a9a28c/32.png) [@Oslo\_Ostragoth](https://boards.straightdope.com/u/Oslo_Ostragoth)\ **Post date:** [September 13, 2009, 5:11am UTC](https://boards.straightdope.com/t/how-do-you-start-a-big-engine/509299/51 "2009-09-13T05:11:12Z")
Excellent links in this thread. Why, yes, in fact I am a Big Machinery geek. [Previous page](https://boards.straightdope.com/t/how-do-you-start-a-big-engine/509299.md?page=2)