One of the mysteries of physiology is the large differences that are seen between individuals in their ability to cope with the reduced oxygen levels experienced above around 2,500m. Simply being fit is no guarantee that someone will cope well at altitude and there is currently no way of prediciting who will have difficulties and who will not. The only guaranteed way of finding out is to go up there. However, with the risk of altitude sickness, this mustn't be rushed, so a gradual programme of height gain is required.
Given that Karl has never been to altitude before (I have been to 4,200m with no ill effects), we need to start gently. Our first trip will be up the Albert Premier hut (at 2,700m) to stay the night. We will walk in from Le Tour, at 1,400m, allowing us to acclimatise psychologically to the scale of the place - this walk is only just over 3km long but gains the height of Ben Nevis, Britain's highest mountain, in that distance. It should sort our legs out! The following day we will climb Aiguille du Tour, at 3,500m, before descending back to Le Tour. This should give us some clues as to Karl's reaction to altitude, as well as to our overall level of fitness, and help in our acclimatisation.
After a few day's rest we will take an early morning cable car up to the Aiguille du Midi ski station at 3,800m. We will spend all day up high and sleep in the Cosmiques hut at around 3,600m. Sleeping at altitude is a great way of letting your body get used to the thinner air, without making too many demands on it. From here we will have a look at our route up. As Karl did very well in the training - not being psyched out by the exposed positions and being competant with ice axes, ropes, harnesses etc. - it should be possible to follow the route in the picture below.
1. Cosmiques hut (3,613m) - leave at 1am
2. Mont Blanc du Tacul (4,248m) around 3.30am
3. Mont Maudit (4,465m) around 5am
4. Mont Blanc (4,9810m) around 8am
Return the same way, catching a cable car back down to the valley floor for mid afternoon.
If the weather, our legs or our lungs are not ready for a summit bid, we will try and do Mont Blanc du Tacul in order to get more altitude in, before returning to the valley floor and resting for a few more days and trying again. We have 2 weeks to do this in, but the longer we take, the less time we will spend with our families - something we are not that keen on!
As I write this, a British climber has been killed on La Tour Ronde (on the other side of the mountain to this picture). An experienced climber who slipped and fell, this acts as a salutory reminder that, no matter how many people say Mont Blanc is easy, all mountians are potential killers - knowing this allows us to understand the risks and make informed decisions. If we are not sure, we won't push it.