The small size and weight of quantum cascade lasers (only ~100 g for HHL housings) make them ideal candidates for integration into remote sensing devices. 
nullIn this paper published by EMPA an Alpes QCL emitting at 7.83 μm is integrated into a hexacopter drone, achieving a methane concentration measurement with a precision of 0.1 ppb. The system was flown in a field study to measure a vertical profile of methane concentration.