UNID Italian speaking OMs 6610 kHz 6610.0 kHz 6.610 MHz USB mode October 15th 2018 - operating within the aircraft band, they sound like the Portuguese guys usually heard on 6925 kHz LSB and similar frequencies, lots laughing, mention of "Francia" and "Espania" several times at 2225 UTC.
The band is quite open and there's lots of weird traffic in the 6 MHz region this evening. This might be Italian or Portuguese. Either way, the OMs who are chatting away on 6610 kHz 6.610 MHz are talking really fast.
They're also a nice legit 3 kHz channel step away from the strong aeronautical HF station on 6607 kHz USB. I distinctly heard "gratzi!" at 2223 UTC. These guys are Italians and are quite talkative.