Photon torpedoes

[Captain Seafort]

Just how powerful are photons? Part of the problem is that we usually see them against shields, which have various strength estimates and so aren't a good benchmark. Thus far I've found three different answers from the TNG TM alone

First the best known:

the maximum payload of antimatter in a standard photon torpedo is...about 1.5 kilograms

Assuming an equal about of matter and using E=mc^2 and a figure of 4.184E15 J for 1 megaton, this gives a theoretical maximum yield of 64.53 Mt.

Fair enough. But then, later in the same book we have this:

*the primary auto-destruct system produces* an energy release on the order of 10^15 megajoules, roughly equivalent to 1,000 photon torpedoes

This information gives a practical yield for a torpedo of 239 Mt - almost four times the theoretical maximum suggested ealier.

But we haven't finished yet. Further down the same page:

The release yield of the secondary sytem is calculated to be 10^9 megajoules, roughly equivalent to 500 photon torpedoes.

This gives a torpedo yield equivalent to just 478 tons of TNT - less than one twentieth of the yield of the device dropped on Hiroshima.

Ideas anyone? Can we reconcile these figures or do we pick whichever one we like best?

[Crushproof]

Torpedoes do exactly what the plot commands them to do. There are times when ships have taken repeated direct hull hits from Photon (and Quantum) Torpedoes without significant damage, and other times when one was enough to do the thing in. (Both of those events occurring in the space of 5 minutes in ST: Generations =P)

[Bryan Moore]

Here's a relevant related question: Do we have an accurate idea of what sort of yield any antimater explosion would have?

[Captain Seafort]

Here's a relevant related question: Do we have an accurate idea of what sort of yield any antimater explosion would have?

Assuming 100% efficiency (which is impossible) half a kilo of antimatter reacting with half a kilo of normal matter would release the total rest energy of that mass - 9E16 Joules, or about 20 Megatons.

[Teaos]

Maybe they are different sizes or ment to do different things?

Like modern day bombs. Some are ment to blow up and cause a lot of damage other are ment to be powerful but very limited kill zone.

[Captain Seafort]

Maybe they are different sizes or ment to do different things?

Like modern day bombs. Some are ment to blow up and cause a lot of damage other are ment to be powerful but very limited kill zone.

Makes sense, especially given we've seen or heard of even wider variations - the cannonball torpedo in "The Final Frontier" and low-gigaton torpedoes suggested by "Pegasus."

[Teaos]

So the different types could be like shield busters and ship damage. Sometimes we see a torpedo blow a ship up usually in battle situations other times they do superficial damge. There seems to be different types or at least yeilds in use.

[Captain Seafort]

The problem is figuring out to what extent the differences are due to different torpedo yields (I can't image a ship in battle setting its torpedoes for less than maximum yield, although there's Bird's of Prey having less powerful weapons would account for some) and to what extent the're due to the damage caused. The tendency of early Galaxy warp cores to go bang if you so much as look at them is but one example.

[Teaos]

Quite often in battle you dont want to destroy the enemy ship just send them running. Thus maximum yeild would not be wise.

[Mikey]

It seems that the yield is set by the operator at the time of launch - presumably by adjusting the quantity of matter and antimatter contained in the torpedo.

[Bryan Moore]

It seems that the yield is set by the operator at the time of launch - presumably by adjusting the quantity of matter and antimatter contained in the torpedo.

Makes sense, as you can't just dump antimatter after firing or anything like that.

Doesn't it say in the TNG Technical Manual that it fires at the speed of light? That doesn't make a lot of sense to me.

[Mikey]

Can't be - maybe 1c faster than the launch vehicle, but that even sounds a little light.

[Teaos]

I would presume the speed can be changed to. I mean look at what we can do with our "smart" bombs. Surely they would have huge control over theirs.

[SolkaTruesilver]

I am not so sure. A photon torpedoes isn't a smart bomb, trying to hit a fix target, it's a missile.

Firing a photon torpedoes at warp speed is like firing a missile when your aircraft is at Mach 6. I think you loose some control over it.

[Crushproof]

Photon torpedoes when launched will go slightly faster than whatever speed the ship is moving at. If the ship is stationary they will move rather slowly (Generations), but at warp they will move even faster thanks to inbuilt Warp sustainer engines (Best of Both worlds, I think).