Ascent:
Mont Blanc du Tacul is easily accessible from Aiguille du Midi tram, which makes it a very popular summit. The E slope of this summit is crossed by several routes including Couloir Jager, which after Couloir Gervasutti is the second corridor to have been climbed on this face. The first climb was made by Pierre Barthélémy and Claude Jager on 12 June 1964.

Couloir Jager shoot is an already long route which proceeds in altitude and can be considered as a training route for a more serious route. You reach it via Aiguille du Midi in around an hour. There is no escape route steps, other than descending the corridor.

From Aiguille du Midi, descend the ridge completely to the E until the altitude of 3670m. From there, pass the bergschrund and go between the large Rognon and Pointe Lachenal. Skirt the S face of Pointe Lachenal and head towards the base of the corridor. Couloir Jager is situated to the right of the more evident Couloir Gervasutti.

Pass the bergschrund which is more or less open depending on the season and go up the corridor primarily via its left bank. It steepens the last 100 meters to reach 60°. At the top out of the corridor, you go to the easier cornice. It takes approximately 3 hours to go up this corridor. This time frame can vary depending on the quality of the snow. Once past cornice, go up the snow ridge until the summit of Mont Blanc du Tacul  (1 h).

Bibliography: - "Neige, glace et mixte" - Publisher Editions Ice Connexion - Itinéraire n° 67g

Descent:
From the summit, head towards the shoulder of Mont Blanc du Tacul and around 4080m, descend completely N then in the direction of the base of the triangle of Tacul by passing successively 2 bergschrunds which can be steep depending on the conditions or the season. From here it is easy to reach Col du Midi then to go back up to Aiguille du Midi  (2h30).

The entire corridor faces E so it gets the sun as soon as it comes up. You need to take this into consideration when deciding when to start. At the altitude of 4,100m, you arrive on the ridge which leads to the NNE facing summit.

There are 200m of HD to reach the foot of the corridor, 600m for the corridor (the steepest -60°- is located at the top of the corridor) and 150m to reach the summit of Mont Blanc du Tacul. To that, add 250m for the return to Aiguille du Midi, for a total of 1200m.

It is necessary to start this route before the sun comes up because of its orientation. This route can be regarded as an acclimatization route before a more serious outing.

Access:
Chamonix -Aiguille du Midi tram as far as the summit. Round trip 34 euro.



Accommodation:
Cosmiques refuge (04.50.54.40 16). Attended from 15 February to 15 October. Half-board for 42 euro.

Crampons, 2 technical ice axes, rings, slings, quickdraws, 2 rappel bits 50m each. Avoid carrying out this route after a snowfall because of the risks of sluffs.