Under water propulsion for a torpedo

[Chas]

I was recently reading about a previous MTB used as a houseboat in Chelsea (pictured above, MTB 219 during her sea-trials) and got to wondering what provided the propulsion under water for a torpedo?

 

[Firewout]

Afaik Batteries + electric motor or a combustion engine + fuel + oxidiser or steam

 

[StarCruiser]

Isn’t it compressed air?

 

[stumog]

Star cruiser is right

 

[StarCruiser]

Star cruiser is right

Hmm, thanks Stu, but according to Wiki, https://www.google.co.uk/search?q=h...lled&ie=UTF-8&oe=UTF-8&hl=en-gb&client=safari
I’m a bit behind the times. Around 100 years ago it was compressed air, then they started injecting kerosene and igniting it. Interesting subject. Looks like Wout is a bit more up to date than I.

 

[stumog]

Hmmm wiki is wrong.....

 

[BobMurphy]

They used a four cylinder diesel motor with the cylinders radiating out in a square formation.

At launch the motor was spun with compressed air to start it. The exhaust exited via four 'flap valves' which produced a characteristic rasp that could be heard by an ASDIC Operator.

However, I guess all sorts of propulsion systems were tried.

Bob.

 

[StarCruiser]

Hmmm wiki is wrong.....

Still compressed air then?

 

[Chas]

With compressed air it's range must have been limited, if it had any sort of combustion engine where did it get air from, I've never seen one with a snorkel.

 

[Richard Turner]

The Russians used Hydrogen Peroxide to make the oxygen. Then it is mixed with Kerosene and burnt.

I don't think other Navy use Hydrogen Peroxide though as it is terribly dangerous, it was the Hydrogen Peroxide exploding that sunk the Kursk, blew the bows off and it sank.

https://en.m.wikipedia.org/wiki/Kursk_submarine_disaster

The problem with using compressed air is that it left a trail of bubbles on the surface meaning ships could manouvere to avoid it, the compressed air didn't just shoot out of the back it drove a propeller.

 

[IRLGW]

Really. So they didn't used to wind up rubber bands then? That's just ruined my day..

 

[stumog]

It's a very complex system not something that you would really come across in any thing apart from defence business. Can't really say more then you can read on the internet sorry.

 

[Higgy]

Our Grandad, Who recently passed away would tell tales of the Atlantic crossings. He was on a ship called the Honeysuckle and were always targets for Subs and he said he use to watch the Torpedo spinning towards them but they would loose momentum after a while and slowly rise to the surface, and just 'Thonk!' into the side of the ship without going off.. Not going fast enough to detonate.. He even said after a while he knew they were never going to detonate, I Guess one never did go off, he died aged 94 in Eastbourne..

 

[Firewout]

Really. So they didn't used to wind up rubber bands then? That's just ruined my day..

Well some early version used a clockwork...
Happy again?

 

[StarCruiser]

You know, I can’t help wondering what brought this up Chas. Are you considering some additions to HMS Phoenix?

 

[Chas]

You know, I can’t help wondering what brought this up Chas. Are you considering some additions to HMS Phoenix?

See original post Rich.