What is this

[Vit]

There is the photo of very interesting thing that pilots had in cabin.

Do you know what is this?

Vít

[VincentB]

The pilot put a pea in each box like a checklist

[Orionis]

C'est un calendrier de l'avent!
It's a kind of an Advent calendar!

[Vit]

[Petr Mikolasek]

To vím opět naprosto přesně. Je to manuál pro začínající letce za polárním kruhem

It is manual for beginners pilots in Arctic areas.

[VincentB]

That's a rosary for the co-pilot, he prays when he fly
more seriously, strange object you must put something in the box? finger? it's for security?

[de Schaetzen Harold]

Some kind of dictionary / language help?
Used when you are landing in the field.

Or a a checklist, as already explained by Vincent?

Is it fixed in a sailplane? You found it in a museum?

Harold

[Thierry Cavalié]

I don't know what it is exactly but I think to a kind of talisman dedicated to a pilot of a german world war two bomber like a Ju 88 because the "Rechts" (Right) cell just before the "Motor" (Engine) one.
In fact, this thing sums up well enough the motives to crash with such aircraft...

Je ne sais pas exactement ce que c'est mais je pense à une sorte de talisman dédié à un pilote de bombardier allemand de la 2ème guerre mondiale comme un Ju 88 à cause de la case "Rechts" (Droite) juste avant la case "Motor" (Moteur).
Cet objet résume assez bien en effet les motifs pour se casser la gueule avec un tel engin...

[Vit]

Hello

I am sending solution of my guess.

On-board accident log for reporting the cause of an accident,late
1920s-early 1930s
Atypical part of aircraft equipment, called Unfallmelder, a sort of counterpart of today´s "black box", was produced and used in Germany. In the event of an accident, the aviator was expected to report its cause. The investigation commitee could later use this "testimony from the grave".

Vít

[VincentB]

Ahoj Vít,
It was a very interesting riddle
but how he marked the box? with a token in the cell? or the background is in paper and he made a hole with finger?