The great Mississippi River flood of 1927 was one of the worst natural disasters in American history. It inundated 27,000 square miles, an area about the size of New England, killing as many as 1,000 people and displacing 700,000 more. At a time when the entire budget of the federal government was barely $3 billion, the flood caused an estimated $1 billion in damage. Although National Guard aviation units had been regularly called upon to assist civil authorities since early in that decade, the 1927 flood marked the first time that an entire Guard flying unit and its government-issued aircraft had been mobilized to help deal with a major natural disaster.
Governor John E. Martineau called up the 10 officers and 50 enlisted members of the 154th Observation Squadron, Arkansas National Guard, to help locate stranded flood victims as well as to deliver food, medicines and supplies to them and relief workers. The unit also conducted aerial patrols along the Mississippi River scouting for weakened or broken levees. Its JN-4 Jenny aircraft flew some 20,000 miles during the mobilization which lasted from 18 April through 3 May 1927. Members of the unit also worked to strengthen and repair river levees.

Flood relief operations took a toll on the 154th. Two aircraft crashed and at least three aviators were injured. The unit's remaining aircraft were grounded for maintenance and repairs at one point. Because of the heavy burden of flight operations, five of the unit's aging JN-4s had to be replaced by PT-1 trainer aircraft in mid-May 1927. The flood relief work of the 154th underscores the long-standing but little understood history of Air National Guard units and their pre-World War II antecedents in supporting civil authorities.