Completing his course at Cranwell in November 1939, Jeffrey returned to Australia the following January as Signals Officer with
No. 3 (Army Cooperation) Squadron at
RAAF Station Richmond, New South Wales. Along with most of his comrades, Jeffrey flew obsolescent
Gloster Gladiator biplanes in support of the Australian
6th Division during the
North African Campaign; he claimed no victories at this stage. Promoted
squadron leader, he took over No. 3 Squadron from Wing Commander
Ian McLachlan on 13 February 1941, by which time the unit had converted to
Hawker Hurricane monoplane fighters. Based at
RAF Benina in defence of
Benghazi when Jeffrey assumed command, No. 3 Squadron retreated eastwards only hours ahead of German tanks after
Rommel launched his offensive in April. The Australians were forced to use ten different airfields in as many days before the Allies regrouped. Jeffrey was flying a Hurricane when he claimed his first aerial victory on 15 April 1941. Following a flight of four German
Junkers Ju 52 transports back to their base near
Fort Capuzzo, Libya, he shot one down before it landed and strafed the other three on the ground, setting all on fire. He was decorated with the
Distinguished Flying Cross (DFC) for this exploit, as well as his "untiring efforts" and "high standard of efficiency ... under extremely trying conditions"; the award was promulgated in the
London Gazette on 13 May. After converting to
P-40 Tomahawks the same month, No. 3 Squadron took part in the
Syria-Lebanon Campaign. Jeffrey scored the unit's first victory in the new fighter when he shot down in flames an Italian
Junkers Ju 88 over the sea near
Beirut on 13 June 1941. Two days later he destroyed a
Vichy French Martin 167 bomber in southern Syria. Jeffrey was credited with another Ju 88 before the squadron returned to North Africa in September to support the Allied counter-attack against the
Afrika Korps. He was
mentioned in despatches on 24 September 1941. As commanding officer of No. 3 Squadron, Jeffrey came up with innovative ways of improving morale in the face of harsh living conditions. On one occasion he arranged accommodation for his men near a beach, well away from the din of night-time bombing that was causing them to lose sleep on a regular basis. Another of his more "radical ideas" and lasting legacies was a combined
mess for all pilots in the combat zone, whether
commissioned or
non-commissioned. The concept was initially frowned upon by
Royal Air Force units, but when Air Vice Marshal
"Mary" Coningham dined at the shared mess on 11 October 1941 and gave his approval, it took root across the entire
Desert Air Force; leading ace
Clive Caldwell later put the same idea into practice as commander of the RAAF's
No. 1 (Fighter) Wing in
Darwin, Northern Territory. One of No. 3 Squadron's
flight sergeants recalled that Jeffrey made it a rule for new pilots to get to know their ground crew to increase their sense of comradeship, and also gave one of his senior
warrant officers special responsibility for keeping track of the location of Allied airfields and petrol supplies to ensure that the unit was never short of fuel or places to land in an emergency. Having been promoted to temporary
wing commander and appointed
wing leader of
No. 234 Wing RAF earlier in the month, He scored his fifth solo victory during the engagement, shooting down a Bf 110, and damaged another. On 30 November, Jeffrey rescued one of his old comrades from No. 3 Squadron,
Sergeant Pilot Allan Cameron, who had crash-landed behind enemy lines. Nicknamed "Tiny", Cameron had the bulkiest frame of any man in the unit, and after landing Jeffrey had to ditch his parachute to make room for his passenger in the Tomahawk's cockpit. He nevertheless managed to take off and return to base, and Cameron went on to survive the war and become an ace in the process. For this and other achievements Jeffrey was awarded the
Distinguished Service Order on 12 December 1941. As well as his rescue of the downed pilot, the citation paid tribute to his "great success" as wing leader, his "fine fighting spirit" in returning to base after having been shot down himself, and to his "magnificent leadership, fearlessness and skill" that had "contributed in a large measure to the successes achieved". At the end of the month, Jeffrey was posted back to Australia to serve in the
South West Pacific. He was credited with a total of five aerial victories in the Middle East, plus one shared and one damaged, though he was considered to be "conservative" in his scoring.
South West Pacific Jeffrey arrived in Australia in January 1942, and the following month briefly took charge of
RAAF Bankstown, New South Wales. Although it included two other veterans of No. 3 Squadron in the Middle East, Flight Lieutenants
"Old John" Jackson and
Peter Turnbull, most of the unit's pilots were untried, and Jeffrey had only nine days to instil in them basic principles of combat flying, gunnery and tactics. He handed over command to Jackson on 19 March, but assisted in ferrying the Kittyhawks to Moresby two days later, only to be fired upon by nervous
anti-aircraft gunners as he came in to land with Turnbull and two other pilots. All four aircraft were damaged, and Jeffrey came within inches of death as a bullet flew past his skull and into the headrest of his seat. By 24 March, No. 75 Squadron had already shot down several Japanese raiders; having overseen its successful establishment, Jeffrey returned to Australia. He immediately began working up a second new Kittyhawk unit for service in New Guinea,
No. 76 (Fighter) Squadron. Based in Townsville at this stage, it was subsequently commanded by Peter Turnbull and joined No. 75 Squadron in the
Battle of Milne Bay. (second from rear), at No. 2 Operational Training Unit, Mildura, in June 1942.|alt=Four single-engined military monoplanes in flight In April 1942, Jeffrey was appointed to establish and command
No. 2 Operational Training Unit (No. 2 OTU). Jeffrey married Colleen Crozier at
Toorak Presbyterian Church in Melbourne on 14 May; his best man was fellow ace and No. 3 Squadron veteran
Alan Rawlinson. The couple had two sons. By this time, Japanese raids had declined in strength and frequency, and Allied forces in the NWA shifted from a defensive posture to assaulting Japanese positions in the
Dutch East Indies and
Western New Guinea. No. 1 Wing intercepted some raiders in late September but none came in October; the last Japanese attack on northern Australia took place on 12 November. Jeffrey was promoted to temporary
group captain in December. He led the wing in its first offensive
strafing operation on 18 April, attacking Japanese positions in the
Babar Islands. The next month, he deployed his headquarters and two squadrons to
Exmouth Gulf in Western Australia to protect facilities that had been established to refuel the British
Eastern Fleet before
Operation Transom. On 5 September 1944, Jeffrey led No. 1 Wing to the
Tanimbar Islands and strafed targets in
Selaru. Later he discussed the mission with Caldwell, who was then commanding
No. 80 (Fighter) Wing and had tagged along to determine if such long-range operations might be worthwhile for his squadrons. Jeffrey declared that the trip was a wasted effort and he had only undertaken it to prevent, in Caldwell's words, "the morale of his pilots going completely down the drain". The following month, Jeffrey was recommended to be mentioned in despatches for "gallant and distinguished service" in North-Western Area; the award was
gazetted on 9 March 1945. Departing No. 1 Wing, in November he returned to the command of No. 2 OTU, in which role he saw out the rest of the war. ==Post-war career==