[2] The 12th Reconnaissance Squadron originated at Kelly Field, Texas in May 1917 when the unit was organized from men picked from about 5,000 aviation recruits being drilled in provisional training companies.

After a week waiting at Halifax Nova Scotia, the trans-Atlantic crossing was made without incident, and the ship arrived at Liverpool, England on 25 December.

The squadron then took a train to Southampton, and made the cross-channel crossing to Le Havre, France, arriving at a British Rest Camp the next day.

[1] After two weeks at St. Maixent, where the squadron largely performed guard duty and drills, orders were received to move to Chaumont-Hill 402 Aerodrome, arriving on 16 January.

In combat, the mission of the 12th Aero Squadron was general surveillance of the enemy rear areas by means of both visual and photographic reconnaissance.

[1] With few exceptions, the 12th’s pilots had never flown combat, but most of the observers had spent a number of weeks flying with French squadrons on active missions.

Returning from a bombing raid on Saarbrücken, the aircraft in which Lt Thompson was operating the rear guns was attacked by German Albatross pursuit ships.

"[6] The 12th’s operations in the Toul Sector was a seasoning period for the squadron as it gained experience over a relatively inactive front with almost no enemy air opposition.

"On the other hand," according to an Air Service report after the war, "the enemy antiaircraft fire in the sector was exceedingly dense, active and accurate.

On 10 June, the 12th Aero Squadron moved to the Baccarat Sector and to the unfinished Flin Aerodrome, from which they supported the 42d American and 167th French Divisions.

This front, too, was considered "stabilized" or quiet, but the opposing German air force, while not flying the latest types, was active and aggressive.

The 12th flew visual and photographic reconnaissance, adjusted artillery fire, and staged "infantry-contact patrols" to locate the front lines.

On 5 July, the squadron moved again to a neighboring field at Francheville in support of the 26th Division, but because of its distance from the front, what would later be known as a "forward operating location," or FOL, was established at Ferme de Moras Aerodrome.

The Allied counteroffensive was launched on 18 July and the squadron's support was vital in photographing targets ahead of the advance according to priorities set by corps intelligence.

The Ferme de Moras location was upgraded to a full airfield on 22 July when the squadron occupied it to participate in the Chateau-Thierry offensive, during which it lost five officers.

Two aircraft, one piloted by Major Lewis Brereton, commander of the I Corps Observation Group and former 12th C.O., were lost, but all four crewmembers survived after landing inside friendly lines.

[9] Personnel at Colombey were subsequently assigned to the Commanding General, Services of Supply and ordered to report to the Le Mans, France, staging camp on 5 May 1919.