One of the more unusual things is you may be asked to do when taking a European flight is to lift the window shade before and after takeoff. On reflection, this may seem completely and utterly pointless. However, there is a bit more to this strange request than meets the eye.

You must lift your window blind when taking off or landing in Europe at night. Photo: Triple Tree via Wikimedia Commons

A popular theory about the window shade instruction is that it prepares passengers for a potentially jolty landing when the wheels hit the concrete runway. On one level, this would seem to make some form of sense, but it doesn't really explain why the window shade needs to be lifted prior to takeoff.

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Aircraft evacuation

The primary reason is instead related to the evacuation of an aircraft. In the case of an emergency evacuation, cabin crew are allotted just 90 seconds in order to ensure that everyone vacates the airplane. Naturally, this is a pretty tight deadline, so some sensible preparation is required ahead of an evacuation.

Of course, this primarily involves the cabin crew preparing passengers for rapid evacuation, but the aircraft must also be prepped by the crew as well. So the lifting of the window shades makes it possible for emergency personnel stationed outside of the aircraft to see into the cabin in order to assess a potential evacuation situation.

And this scenario only applies when taking off and landing, as an emergency evacuation will never occur at the height of 20,000 feet.

Photo: Getty Images

Passenger experience

One can understand the curiosity about this issue, and it is indeed this curious nature of passengers that can prove particularly useful in an emergency. Somewhere down the line, airlines realized that passengers actually make perfect extra sets of eyes, ensuring that if anything is going wrong with the evacuation process, then it is spotted rapidly.

There is another explanation for this policy as well, and it also relates to emergency situations. When you're sitting within the cabin of an aircraft, natural acclimatization into lower-light conditions is an automatic functioning of the human retina. This can then cause problems in an evacuation scenario if you are forced to disembark from an aircraft rapidly.

While European airlines require window shades to be lifted, this often doesn't apply in the US. Photo: Ryanair.

Not standard procedure

So there is a common-sense reason for the lifting of the window shade. Thus, what is also interesting is that this procedure isn't a standard policy on every airline and isn't required by carriers in the United States. Once you understand the reasoning behind this, it's hard to understand why, and certainly, there is no official explanation given for this currently.

Several pilots have commented that passengers have picked up some technical issues with aircraft on rare occasions and that this can be a valid reason in itself for having the window shades open. But it seems that this is one area in which European and American airlines see things differently.

What do you think of opening window shades during take-off and landings? Let us know in the comments.