While the McConnells were in New York their son, Rogers, died of a fever. Following his untimely death Sarah McConnell became a "nervous invalid," who relegated the responsibilities of her youngest children to her daughter, Julia. Eventually the McConnell's were divorced, and in 1902 Judge McConnell married Mayo Methot, a domestic servant. From that union another son and two daughters were born. While still in his pre-teens, young James McConnell spent a portion of his childhood in France with his mother and two small sisters. And it was there that he had learned to speak French fluently. In his youth he had suffered from muscular rheumatism which again surfaced with savage intensity in his adult life.

Although he continued to fly for several days after his accident, soon he could not dress himself and could only walk with a cane. He took a brief Paris leave, hoping the condition would abate. But by the time he returned to Bar-le-Duc he could not walk. On 26 August Capitaine Thenault ordered him to hospital. McConnell vigorously protested, saying: "Not being able to walk does not prevent my flying." Thenault merely replied, "Jimmy, go to bed." and ordered McConnell to the auxiliary hospital at Vitry-le-Francois. While in hospital McConnell wrote a 19 September 1916 letter to a friend in Paris. "I am getting discouraged about my back," he had said. "It seems to be getting well and then flop, she drops back to first condition. If it doesn't build up soon, I am going to tell them I am well." McConnell became ever more anxious to rejoin the Squadron upon hearing of the death on 23 September of Kiffin Rockwell, his closest friend. But he knew that physically he could not. He requested his doctor's permission to journey to Paris to continue his recuperation at the residence of Mrs. Alice Weeks. McConnell arrived in Paris on the 27th and recuperated for 45 days at Mrs. Weeks's apartment at 80 Rue Boissiere. He used the time to work on the book he had begun in the hospital concerning his experiences with the Escadrille Americaine.

On 11 November, although not yet well, he left Paris to rejoin the Squadron at Cachy in the Somme sector. Inclement weather had kept the Squadron grounded through much of November and early December. Mrs. Weeks had booked passage to the United States, and McConnell hurried to complete his manuscript, hoping she could deliver it to Doubleday Page & Company, his New York publisher. Unable to make the deadline for her departure, he sent on an article with her for "World's Work" magazine while making other arrangements for the manuscript. He wrote this explanation to her in a 11 December letter: "Between a bad cold, the general cold and the fact that Whiskey chewed up my fingers, I have been unable to write and will have to send over the rest of copy for my book by Dudley." (Escadrille pilot Dudley Hill from Poughkeepsie, New York who was soon to return home on leave.) Throughout the month of January 1917, McConnell fought two undecisive combats. On the 26th the Squadron was transferred from Cachy to Saint-Juste. Upon returning from a Paris leave, on 7 February, Sergeant McConnell wrote a letter to Mrs. Weeks, now in the United States, detailing life at the new aerodrome. "We have much better barracks but just now it is fearfully cold. The machines freeze up while one is flying. ... I have never seen such a spell in France before. Worst winter since 1870. Whiskey ate up my fatigue cap and last night my kepi. Yes, Page (Frank C. Page, editor of Doubleday Page & Company) got the manuscript. Book will be out the 20th of this month."The aching cold that had nestled in around the aerodrome aggravated the rheumatism in McConnell's back, and by the second week of February Thenault had ordered him back to the hospital. While he was there his book, titled Flying For France, was released by Doubleday. It was favorably received in the United States and helped to elevate the patriotic sentiment in a nation about to enter the War. It is a marvelously well-written book and clearly indicated that McConnell had genuine ability as a writer. Compelled by his sense of duty, McConnell left the hospital a virtual cripple against his doctor's orders. By 21 February he had returned to the Squadron to fly volunteer missions with Lieutenant deLaage against enemy observation balloons.

While there, he required help to dress and had to have his mechanics lift him into his fighter. The rheumatism in his back had dangerously restricted the head movement required for total vision, an essential for survival in the air. The day following his return to the Squadron, Sergeant McConnell wrote a letter dated 23 February to Frank Page, his editor at Doubleday, thanking him for his first royalty check of 861 francs. He went on to say: "Had rotten luck the other day. Caught a fat Boche five kilometers in our lines and my machine gun wouldn't work. I stayed near him trying to fix it until he regained his lines. I could have cried." McConnell concluded by saying he hoped to so on transfer to the American Aviation Service with anticipation of a high rank, since he and William Thaw were the senior men in the Lafayette Squadron.

The eve before McConnell's 30th birthday, 13 March 1917, found him in a pensive mood. The last sentence in his diary that day suggested he had a prescient sense of his fate: "This war may kill me, but I have it to thank for much." Edwin Parsons later recalled how the morning of 19 March 1917 had been a "lowering, gray day with storm-driven scud." He, Sergent James McConnell, and Caporal Edmond Genet had been scheduled for the 10 a.m. patrol over the Somme battlefield. McConnell and Genet left the airstrip first, followed by Parsons. Parson's oil line clogged shortly after he had cleared the field, immediately burning up his motor. He brought his fighter down two kilometers from his aerodrome as his two friends continued on toward German territory. Deep inside enemy lines McConnell and Genet ran upon two German two-seaters north of Ham. Genet later related the events in a letter to his mother. The last sight Genet had of McConnell as Edmond attacked the nearest German bus was of his friend pursuing the second enemy plane. Genet fought a fierce combat between clouds and mist which saw his fighter heavily damaged and his left cheek cut open by a bullet fragment. Stunned, Genet still remained in the zone of combat for fifteen minutes, searching for McConnell. Bleeding, in pain, his fighter in danger of losing its upper wing, Genet only reluctantly returned to the aerodrome, hoping that McConnell had already returned to the field. When McConnell failed to appear from patrol, his comrades began the long wait on the tarmac. Capitaine Thenault hovered near his phone anxiously awaiting word of McConnell's fate. At day's end their only hope was that their friend had been shot down and taken prisoner.

On the night of 23 March, all hope was dashed when Commandant Fequant, head of Croupe de Combat 13, received a telephone call from the Front that a French cavalry patrol had discovered a crumpled Nieuport bearing McConnell's number 2055 on its rudder. The wreckage was in a small apple orchard at the southern edge of the little village of Detroit Bleu. Nearby was a dead pilot, his body stripped by the Germans of his outer clothing, boots, i.d., and watch. Thenault, Lieutenant deLaage, and several American pilots drove to the crash site to take charge of McConnell's body. En route, deLaage was grieving openly and recalled the previous Christmas at Cachy when the pilots had dined together in their barracks. There had been thirteen men at the table, and McConnell had made reference to this superstitious number. When deLaage had asked his friend what that superstition was, McConnell had explained how "with thirteen at table it was supposed that one of the assembly would die within the year." deLaage had remembered how he had laughed that Christmas, while this day his words returned to haunt him. "Well," he had told his friend, McConnell "it will hold good with this crowd. But unfortunately there will probably be more than one." deLaage's words proved prophetic. He himself would also be killed, on 23 May 1917, just two months from that very day they had gone to recover McConnell's body. As McConnell's friends gently picked up his remains for burial, they witnessed several bullet holes in his body, any one of which would have proved fatal. A peasant woman came forward who had seen McConnell's last combat. She related how she had watched him engage a German airplane when a second enemy plane had dived on him from behind and had shot him down. Capitaine Thenault, upon first learning of McConnell's death, had opened a note the pilot had left to be read in the event of his death. As a last gesture of his generous nature and concern for others, McConnell had willed his sleeping bag to Edwin Parsons, knowing his friend hadn't the francs to purchase one and had suffered from the bitter winter's chill. The note also contained McConnell's last simple request: "My burial is of no import. Make it as easy as possible for yourselves. I have no religion and do not care for any service. If the omission would embarrass you, I presume I could stand the performance. Good luck to the rest of you. God damn Germany and vive la France." In conjunction with McConnell's wishes, Capitaine Thenault assembled the pilots where their comrade had fallen, and together they gently and quietly placed him in the devastated earth at Petit-Detroit, southeast of Ham. The French 165th Infantry used stones from a nearby ruined village to erect a monument to McConnell. Eventually, the citizens of Ham raised the funds to provide a cement tomb and a memorial stone for McConnell. Sergent McConnell was posthumously awarded France's Croix de Guerre, with Palm. The accompanying citation spoke of a "pilot as modest as he is courageous." Paul Rockwell, Kiffin's brother, came to the Squadron to see to Jim's effects. He was heart struck by McConnell's death and said of him "I never had a better friend except Kiffin."

On 2 April 1917, morning services were held in McConnell's honor at the American Church in Paris. Many dignitaries were present including American Ambassador, William G. Sharp. Also represented were members of the Lafayette Flying Corps and the American Ambulance Service. Three tearful mesdemoiselles also attended, each one believing she was McConnell's fiance. One would later marry another Lafayette Escadrille pilot. The speech delivered by Bishop C.H. Brent spoke eloquently of McConnell's devotion. But perhaps the most fitting eulogy was delivered several weeks later by Emil Marshall, McConnell's comrade, in a 1 May 1917 letter to a mutual friend: "I often think of you and poor Jim...He had done so much for me. One of my greatest pleasures would have been to show him some day how much I appreciated it. I had so looked forward to that. Now it is impossible. All I can do is to always remember him as the best and bravest comrade one could have wished." James McConnell was the first University of Virginia alumnus to die in World War One. A statue in his honor titled Aviator rests on the University grounds. It was sculpted by Gutzon Borglum, who later planned the South Dakota Mount Rushmore Memorial. In 1928, McConnell's body was placed in the crypt at the Lafayette Escadrille memorial near Paris, there to rest in eternity with his comrades.