Naval Historywith Dr. Alex

Q&A · 4:50:30-4:51:19

How steam warships made smoke screens

Boiler crews could make smoke by changing combustion or adding material to the uptakes, and Iowa-class sight glasses let them inspect the result.

BoilersIowa Class BattleshipsNaval EngineeringSmoke Screens
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Question

How did smoke screens work in the age of steam and steel?

Short answer

Crews changed the fuel-air mixture or added material to the exhaust uptakes to produce visible smoke.

Notes

Steam warships could make visible smoke by changing the fuel-air mixture entering their boilers. Additives introduced into the uptakes provided another method. Iowa-class ships had periscope sight glasses that let boiler crews inside the citadel inspect the smoke leaving the funnels. The colour gave those crews a way to observe the result from their protected working spaces.