[1] Langlais distinguished himself as a promising young battalion commander in the bitter house-to-house fighting prevalent throughout this battle, which eventually resulted in the French reoccupation of Hanoi.

[1] Returning to France, in October 1951 Langlais was given command of the 1st Colonial Para-Commando Demi Brigade (1 DBCCP), training replacements for Indochina.

In order to take this assignment Langlais, who had only ever served in the Compagnies Méharistes or light infantry regiments, trained as a paratrooper.

[1]: 15–6  Langlais returned to Dien Bien Phu with his foot in plaster on 12 December 1953 to take command of all airborne forces in the valley.

The operation was a failure; GAP 2 was repeatedly ambushed along the Pavie Track and reached Muong Pon after the garrison had been overrun.

[1]: 68–71  On 21 December GAP 2 launched another reconnaissance raid called Operation Regate to the Laotian town of Sop-Nao to link up with a Laotian-Moroccan-French force coming from Laos.

[1]: 78–82  On 17 February, faced with ongoing losses to the garrison, General René Cogny ordered that henceforth only light reconnaissances be conducted by limited numbers of personnel.

[1]: 84  On 11 March Langlais led GAP 2 on its last large reconnaissance operation against Viet Minh trenches being dug on Hill 555 overlooking Strongpoint Beatrice, only 3.2 km from the central position.

[1]: 138–9 As the French position in the valley came under increasing pressure, de Castries became withdrawn from the men under his command and began to rarely leave his underground headquarters.