Editing Battle of Dien Bien Phu (section)

=== Trench warfare ===
[[File:Dien Bien Phu002.jpg|thumb|French troops seeking cover in trenches.]]

On 5 April, after a long night of battle, French fighter-bombers and artillery inflicted particularly devastating losses on one Viet Minh regiment<!-- which one?? -->, which was caught on open ground. At that point, Giáp decided to change tactics. Although Giáp still had the same objective – to overrun French defenses east of the river – he decided to employ [[trench warfare|entrenchment and sapping]] to achieve it.{{sfn|Davidson|1988|pp=254–55}}

On 10 April, the French attempted to retake ''Eliane'' 1, which had been lost eleven days earlier. The loss posed a significant threat to ''Eliane'' 4, and the French wanted to eliminate that threat. The dawn attack, which Bigeard devised, began with a short, massive artillery barrage, followed by small unit [[infiltration tactics|infiltration attacks]], then mopping-up operations. ''Eliane'' 1 changed hands several times that day, but by the next morning the French had control of the strong point. The Viet Minh attempted to retake it on the evening of 12 April, but were pushed back.{{sfn|Davidson|1988|p=265}}

At this point, the morale of the Viet Minh soldiers was greatly lowered due to the massive casualties they had received from heavy French gunfire. During a period of stalemate from 15 April to 1 May, the French intercepted enemy radio messages which told of whole units refusing orders to attack, and Viet Minh prisoners in French hands said that they were told to advance or be shot by the officers and non-commissioned officers behind them.{{sfn|Davidson|1988|p=256}} Worse still, the Viet Minh lacked advanced medical treatment and care, leading a US general commenting on the war to observe that "Nothing strikes at combat-morale like the knowledge that if wounded, the soldier will go uncared for".{{sfn|Davidson|1988|p=257}}

During the fighting at ''Eliane'' 1, on the other side of camp, the Viet Minh entrenchments had almost entirely surrounded ''Huguette'' 1 and 6. On 11 April the garrison of ''Huguette'' 1, supported by artillery from ''Claudine'', launched an attack with the goal of resupplying ''Huguette'' 6 with water and ammunition. <!-- Confusing to start this paragraph by describing Viet Minh actions and suddenly shift to describing French actions&nbsp;– but without naming the forces in question. --> The attacks were repeated on the nights of the 14–15 and 16–17 April. While they did succeed in getting some supplies through, the French suffered heavy casualties, which convinced Langlais to abandon ''Huguette'' 6. Following a failed attempt to link up, on 18 April, the defenders at ''Huguette'' 6 made a daring break out, but only a few managed to make it to French lines.{{sfn|Davidson|1988|p=258}}{{sfn|Fall|1967|p=260}} The Viet Minh repeated the isolation and probing attacks against ''Huguette'' 1, and overran the fort on the morning of 22 April. After this key advance, the Viet Minh took control of more than 90 percent of the airfield, making accurate French parachute drops impossible.{{sfn|Fall|1967|p=270}} This caused the landing zone to become perilously small, and effectively choked off much needed supplies.{{sfn|Davidson|1988|p=259}} A French attack against ''Huguette'' 1 later that day was repulsed.{{sfn|Windrow|2004|pp=532–533}}