'Elmira' was a US gliderborne landing to deliver reinforcements to Major General Matthew B. Ridgway’s 82^nd Airborne Division after its 'Boston' (ii) assault and 'Detroit' initial reinforcement operations during 'Overlord' (6 June 1944).

On the evening of D-Day two additional gliderborne operations, 'Elmira' and 'Keokuk', had brought in additional support in 208 Waco CG-4A and Airspeed Horsa gliders towed by Douglas C-47 Skytrain twin-engined tug aircraft of Brigadier General Paul L. Williams’s IX Troop Carrier Command of Lieutenant General Lewis H. Brereton’s 9^th AAF.

Both operations were completed before the fall of night on 6 June, and were heavily escorted by Lockheed P-38 Lightning twin-engined, Republic P-47 Thunderbolt single-engined and North American P-51 Mustang single-engined fighters. 'Elmira' was essential to the 82^nd Airborne Division, for it delivered the 319^th and 320^th Glider Field Artillery Battalions with 24 howitzers to support the US 507^th and 508^th Parachute Infantry, which lacked artillery support, to the west of the Merderet river.

The operation comprised four serials of tug/glider combinations: the 50 aircraft of Colonel Frank J. MacNees’s 435^th Troop Carrier Group towed 12 CG-4A and 38 Horsa gliders as the fourth serial, the 50 aircraft of Colonel Adriel N. Williams’s 436^th Troop Carrier Group towed two CG-4A and 48 Horsa gliders as the third serial, the 26 aircraft of Colonel Cedric E. Hudgens’s 437^th Troop Carrier Group towed eight CG-4A and 18 Horsa gliders as the first serial, and the 50 aircraft of Colonel John M. Donalson’s 438^th Troop Carrier Group towed 14 CG-4A and 39 Horsa gliders as the second serial.

The first pair was to arrive 10 minutes after 'Keokuk' and the second pair two hours later at sunset. The first gliders, unaware that the LZ had been moved to LZ O, came under heavy Flak fire from German troops who occupied part of Landing Zone W. The C-47 tugs released their gliders for the original LZ, where most delivered their loads intact despite heavy damage. The second wave of 'Elmira' arrived at 22.55, and because no other pathfinder aids were operating, they headed for the 'Eureka' beacon on LZ O. This wave also came under severe Flak fire as it passed directly over German positions. One serial released early and its gliders came down near the German lines, but the second came down on LZ O.

Nearly all the men of both battalions had joined the 82^nd Airborne Division by the morning of 7 June, and 15 guns were in operation on 8 June.