Supervisory control of uninhabited aerial vehicles requires vigilance, also termed sustained attention. This pilot study investigated the efficacy of short duration vibrotactile signals presented on the waist at intermittent periods as a countermeasure for sustaining performance in auditory and visual vigilance tasks that were equated in discrimination difficulty. Performance with the vibrotactile stimulation countermeasure was compared against performance with a rest break countermeasure. Participants were randomly assigned to one of eight groups. The groups were defined by combinations of sensory modality (auditory or visual), and type of countermeasure (control, rest break, low vibrotactile signals, or high vibrotactile signals). For each sensory modality, participants performed a monitoring task that was comprised four 10-minute vigils. The administration of the rest break and vibrotactile countermeasures occurred following the third vigil for each sensory modality. The results of the pilot study showed greater performance improvement in the auditory modality than the visual modality. In the auditory modality, the two vibrotactile countermeasures appear to have some benefit for sustaining performance but not as much as the rest break, whereas, in the visual modality, the three countermeasures had no benefit for sustaining performance. These preliminary findings encourage further investigation of the efficacy of vibrotactile stimulation as a countermeasure for sustaining performance in a vigilance task for both auditory and visual modalities.