January 27 in the morning final exchanges with Minerva
01:15The submarine landed the LV Merlo in the roadstead of Les Vignettes with great difficulty due to the storm, then returned offshore to carry out exercises in the diving sectors near Toulon (T65-T66).
07h30 Exercises are carried out with an aircraft of the Breguet-Atlantic type and focus on the implementation of airborne submarine detection systems: JULIE, MAD, and RADAR. They are approved throughout NATO and do not involve any particular risk. The ship was then 25 nautical miles (46 km) from the coast.
07:19 The Breguet-Atlantic FXCVA made contact with the submarine by UHF radio, and canceled the planned exercises due to unfavorable weather and replaced them with two simpler Radar calibrations.
07:25 The submarine broadcasts in UHF. The airplane detected the transmission in the 081 azimuth then came on an average route to the East to carry out evolutions intended to check its MAD.
07:33 Beginning of the rallying of the plane, heading at 090, on direction finding of the UHF emissions of the submarine.
07:34 The needle of the gonio[1] swings to the right, the "Proximity" light comes on which generally indicates that the submarine is less than 5 N. The plane ends its roll with a turn to the right. The submarine is not sighted, although it is close and snorkeling[2] at a position which is estimated by the aircraft
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at 164 Cap SICIE 24
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i.e. at Latitude 42° 39.8 N and Longitude 6° 00.5 E, i.e. at 9.5 N in the 110 SE corner of T65.
07:35-07:45 The aircraft deviates from the middle course to the south for a radar calibration. The objective for the radar operator of the Bréguet, is to define the radar signature of the submarine in periscopic immersion. Any surface building near the submarine will be obligatorily spotted.
The UHF link is poor. The sub reports that it is having difficulty on this link due to sea conditions and asks if it should continue to transmit ARUR levels. The plane replies that it is no longer necessary.
07:40 The aircraft identified a 6,000 ton freighter 15 N south of MINERVE.
07:43 The submarine detects Radar emissions from the aircraft in the 160 azimuth
07:45 The plane turns around and comes to 350
07:55 The aircraft commander decided not to continue the calibration tests:
"I intend to cancel the radar check at 0800 hours."
"I understand you are canceling this verification, did you hear me?"
"I heard you"
The plane moved away then passed abeam of an oil tanker en route to Marseilles.
07h55-08h09 The aircraft tries unsuccessfully to re-establish UHF contact to do homing according to the SUNLAMP procedure
08:24 The airplane repositions correctly on the PLANIER at the end of the mission.
Maritime map indicating the T5 and T66 exercise areas where operated La Minerve. Bottom depths are indicated.
Journey of the Breguet-Atlantique at the moment of its last contact with La Minerve (approximate scale and enlarged for readability). The blue dot indicates the last known position from the submarine.