International audience Risk prevention related to complex extended cavities raises often strong economic, social and/or technical issues for local authorities and decision-makers. Remote monitoring offers a median way of vulnerability mitigation. However relevant monitoring of those geohazards calls for innovative volumetric methods to meet reasonable cost/benefit ratios, as microseismic and aerial acoustic monitoring techniques. Aerial acoustic technique has been developed and tested by INERIS in several underground contexts. This paper presents feedback from both experimental and operational case studies, presents results and recommendation for proper field application