After receiving flight training in New Zealand and Canada, he was sent to England to serve with the Royal Air Force.

In June 1942, he was sent to Malta as a reinforcement pilot, flying a Supermarine Spitfire off the flight deck of HMS Eagle to the island where he joined No.

[1][2] The family lived in the Auckland suburb of Parnell and Stenborg was educated at King's College, where he played in the school's first XI.

[3] In July 1940, Stenborg joined the Royal New Zealand Air Force and underwent initial training at Whenuapai on Blackburn Baffin and Vickers Vildebeest aircraft.

[2] With mostly New Zealand flying personnel and equipped with Spitfires, this was based at Kenley and engaged in the RAF's Circus offensive.

In early June 1942, Stenborg, now a pilot officer, was sent to Malta, sailing aboard the aircraft carrier HMS Eagle as a reinforcement for the squadrons operating from the island, besieged by the Luftwaffe and Regia Aeronautica (Royal Italian Air Force).

He flew a Spitfire off the flight deck of Eagle early in the morning of 9 June and on arrival at Malta was assigned to No.

[8][9] One of four pilots from the squadron scrambled in the evening of 15 June to deal with a bombing raid on a convoy off Malta, he damaged two Junkers Ju 88 medium bombers and destroyed an escorting Messerschmitt Bf 109 fighter.

[7][10] He shot down two Bf 109s on 5 July; they were part of a group of between 15 and 20 fighters escorting Ju 88s making a bombing raid on Malta.

[7][11] Another two Bf 109s were destroyed by Stenborg on 9 July, when he was part of a group of 30 Spitfires that intercepted six Ju 88s and escorting fighters raiding Takali.

[13] The citation, published on 28 July in the London Gazette, read:Pilot Officer Stenborg has displayed great determination and keenness to engage the enemy.

He was eventually able to bale out, landing in the sea 8 kilometres (5.0 mi) from Malta and taking to his inflatable dinghy before being rescued.

185 Squadron, Stenborg returned to England in late August and spent a period of time on instructing duties at No.

[2][4] This was based at Hawkinge and was equipped with Mk XII Spitfires, flying on offensive sorties to German-occupied Europe and escorting bombers.