The ‘JANUS IV’ Sea-Dwellers

From 1968 to 1977 COMEX conducted a series of experimental dives in conjunction with the French Navy, to a variety of depths ranging from 150m, to the famous 501m world record.

John McKenna was one of 8 divers selected for the pre world record JANUS IV dive to 460m.

Please refer to attached newspaper article and page 11 of the COMEX 2000 essay 36 years of deep diving and submariner technique development (below).

Of the 8 divers used in the Janus IV Phase A dives, 6 were then selected (based on age, fitness and weight) for the final Janus IV Phase B dive to 501m

The newspaper article below ‘The Heroes of JANUS’, describes the feat and pictures the 8 divers, as follows (Clockwise from left to right)

Jaques Verpeaux
Patrick Roude
Gerard Vial
Louis Schneider
Phillip Clottas (supervisor)
Emile Sevellec
John McKenna
Phillipe Jeantot
Vito Lentin


I met with John for the first time in the summer of 2007 after many months of correspondence, and spent several very enjoyable hours speaking about his career and the Janus IV dives that he participated in.

I also acquired from him the watch he was given on selection for the JANUS IV dive, which was subsequently engraved to commemorate the achievement.

The watch (pictured below) has clearly seen better days, although that is not a surprise, considering its constant use as a dive watch from 1976 to 1993 (+ during this time it was never serviced).

It is a Rolex Double Red Sea Dweller model ref. 1665 DRSD with a 4 million serial matching numbers and case back inscription of

DEC 1976

The watch was presented to the divers on initial selection and engraved after the dives.

Its current condition is also rather secondary in comparison to its originality and significance, i left the watch untouched, simply cleaning the movement and freeing the dial of any debris.

John McKenna’s Personal Biography

Born in 1938, John McKenna started diving for universal divers in 1964 (unqualified)

Whilst working offshore as a barge engineer on a jet barge in 1972, during force 9 gale a passenger fell overboard; John followed the passenger into sea and rescued him without the aid of any diving equipment or fins.
As an acknowledgement for his bravery and skill, the diving superintendent of the barge at that time offered John further diving work with him, which then led to his eventual employment with COMEX, Aberdeen.

In 1976 COMEX Marseille were recruiting for a French Speaking British diver for some experimental dives that they were conducting.

In spite of his age John applied and passed all of the required selection tests with flying colours (Having recently won his green beret at the Royal Marines Commando Training Centre in Limpston) and so was selected for the Janus IV Phase A experiment, successfully diving to 460m.

John McKenna continued working as a diver until the age of 55, before taking a well earned pension. He then emigrated with his family to Hatyai in Thailand, where he worked as English teacher at the Hatyai University, spending his time between his family’s home in Thailand and his native Liverpool.

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