It was another registration (now confirmed): CX-LAS
I've translated and transcribed parts of that:
Carrasco tower: TWR
Montevideo control: CTR
Several communications made by LAS are not heard in the recording.
Between brackets (), comments I added.
TWR: LAS, Carrasco. It's here (the flight plan). Carrasco - Ezeiza, level 100, transponder 6045, runway 24, 260 degrees 20 to 25 knots, setting 1023 (hPa).
TWR: Ok, can the departure be made a bit earlier, or it must be on the time?
TWR: Perfect, contact when ready to taxi. 7 degrees (C°) the temperature.
TWR: Via Charlie or Delta, as you wish, for runway 24. What's better for you?
TWR: Charlie and report ready holding short.
TWR: AS, copy?
TWR: Climb at your discretion to 100.
TWR: Affirmative, cleared for take-off, runway 24, 240 25 knots, I have a gust to 27 now.
TWR: LAS, 55 (7:55, take-off time), contact Montevideo on 128.5, have a nice flight.
LAS: 128.5, till later and thanks, LAS.
LAS: Montevideo, [unintelligible] LAS, good night.
CTR: Good night LAS, radar contact, right turn, direct SARGO, 100.
LAS: Is it Ok if we request FL 080 for LAS?
CTR: 080, cleared.
LAS: Cleared for 080, LAS
CTR: LAS, Montevideo
LAS: We are turning towards SARGO, LAS (that was the last com from the plane)
CTR: Very well.
CTR: LAS, Montevideo.
CTR: CX-LAS, Montevideo.
CTR: AS, Montevideo.
TWR: (calling to airplanes on ground) There is an aircraft that lost radio and radar contact with th radar (i.e. with Montevideo control) and we are waiting further instructions for your departure from them, hold on your positions until then.
Several airplanes acknowledge.
Then there is another voice (with background noise) saying "We have an airplane that the last known position was the Flores island, a little to the right of the Flores island, we lost radar contact and they don't replay the radio calls. Caution with the landing, we don't know where it may be now."
Two airplanes acknowledge.
In another call to an airplane on ground who asks for the fate of the airplane, the tower says that they lost radar contact and radio contact and cellular phone calls were unsuccessful too.
In another call the tower says: "In the last contact the plane was South of the field with 3000 feet. They've always been to the South."
- The Rio de la Plata showing several key points.
- A zoom-in around the Carrasco airport and the Flores island.
- A part of the Carrasco standard departures chart (SID) for runway 24
I don't understand how an airplane that departed towards the South-West (runway 24) going to Ezeiza via SARGO, that acknowledge a right turn to SARGO and later confirmed that they were turning to SARGO, can end near the Flores island some 8NM South-East of the airport (I added a red F in the SID chart that shows its approximate position)