The plural form of 'Hovercraft' is-

কতগুলো শব্দ আছে যাদের singular এবং plural form একই রকম থাকে।
যেমন- Sheep, Deer, Score, Swine, Canon, Corps, Offspring, Series, Carp, Cod, Pair, Dozen, Species, Aircraft, Hovercraft, Spacecraft, Dice, Public, Pair, Pike, Gross, Hundred, Thousand, Million ইত্যাদি।