Ineffectual

ineffectual \in-ih-FEK-choo-uhl\, adjective:
Not producing the proper effect; without effect; weak; useless; futile; unavailing.

Rush, the aging black Labrador that had waited patiently outside during lunch, ran joyfully on the beach, splashing in the water, making ineffectual attempts to catch a seagull.
-- Annabel Davis-Goff, The Dower House