[6] Marix learned to fly at the Bristol School on Salisbury Plain,[7] where he was awarded Royal Aero Club Aviators' Certificate No.

On 4 August 1914 Britain declared war on Germany, and three RNAS squadrons were soon deployed to Belgium and France primarily to fly reconnaissance missions, but also found themselves operating armoured cars.

For the first mission on 22 September, Baron Pierre de Caters provided a force of Belgian armoured cars which was sent out to create and defend a forward landing strip west of the Meuse, as the British aircraft did not have sufficient range to fly directly to their targets and back.

By the time the four aircraft crossed the River Roer, fog obscured the ground and Collet was the only pilot to find his target, the airship shed at Düsseldorf.

[16][17] On 28 September Antwerp came under attack by German heavy guns, and the RNAS aircraft assisted the Belgian defenders by flying artillery spotting missions.

[16] (Contemporary despatches and accounts state that Flight Lieutenant Sydney Vincent Sippe also took part in the raid, but was forced down before reaching German territory by a mechanical failure.

Marix had more luck, finding his target at Düsseldorf and dived from 3,000 to 500 feet before releasing his bombs, in the face of heavy rifle and machine fire from the ground.

Marix's aircraft sustained some damage from anti-aircraft fire, but he managed to fly to within 20 miles of Antwerp before having to land, and travelled by train and a borrowed bicycle to the aerodrome, which he found deserted apart from Grey, Sippe, and a party of Royal Marines.

The two men returned to the aircraft where Marix courteously lent his captive a revolver to administer the coup de grâce to his suffering mount, before taking him back to the British lines.

A further reconnaissance flight led the British to conclude that the Turks were preparing an attack on Anzac Cove, and as a result their assault of 19 May was effectively repulsed with great loss of life.

However, in May 1916, a new Anglo-French strategic bombing force was created, under the command of Wing Captain William Leslie Elder, of which Marix's squadron formed the nucleus.

3 Wing RNAS, the British aircraft were based at Luxeuil-les-Bains, close to France's eastern frontier, and comprised Sopwith 1½ Strutters and Breguet Bre.5 bombers.

Marix remained with the RAF post-war and on 1 August 1919 was awarded a permanent commission with the rank of major (later squadron leader).

[32] On 11 July 1922 he was awarded the Croix de Guerre avec palme by the King of the Belgians for his "valuable services rendered in connection with the war".

[3] On 3 September 1939, the day Britain declared war on Germany, Marix was granted the acting rank of air vice marshal.

45 Group in collaboration with the American Air Transport Command, in anticipation of increased activity in the South West Pacific theatre.

[64] Marix then served at the Headquarters of Transport Command,[65] until retiring from the RAF on medical grounds on 6 December 1945, retaining the rank of air vice marshal.

[3] In May 2016 his medals, logbook and service revolver were donated to the RAF Museum by his 91-year-old daughter-in-law Yvelene de Marcellus Marix in Washington D.C.[65]