Chapman's archipelago frigates provided better protection for their crew than the galleys they replaced, and up to three times the capacity for stores and provisions. They could operate in the narrow, shallow waters around skerries in all weathers and in open water in all but the worst storms. They had a deeper draft than galleys, but considerably shallower draft than traditional sailing warships. The new ship types also increased the archipelago fleet's firepower, provided it with better defensive capabilities, and made possible more efficient fire support in amphibious operations.
Hemmemas served in the Finnish squadrons during the war of 1788–1790. They supported amphibious operations and conducted raids on the Russian archipelago fleet, while at the same time acting as sea-borne flank support for the Swedish army on the Finnish mainland. Hemmemas fought in the first and second Battles of Svensksund. During the first battle in 1789, one hemmema complemented the similar turumas, and in the second battle in July 1790, two hemmemas made up the defensive center and provided a considerable percentage of the firepower.
Like the other specialized archipelago vessels, the hemmema had specific strengths and weaknesses. Although it had superior firepower relative to galleys, its sailing qualities were somewhat mediocre and while highly manoeuvrable under oars, it was still difficult to propel while rowed. A hemmema had the potential to be an effective weapon against galleys, matching their forward firepower and severely outgunning them with its broadside armament. Inside an enemy galley formation, it could wreak considerable havoc, but such a maneuver was never achieved in an actual battle, leaving that tactical role untested.