"Je ne vais pas pouvoir monter sans échelle."

Translation: I'm not going to be able to climb up without a ladder.

[JamesPyrah]

Why not "a" ladder?

[Ronnie-JA]

https://www.lawlessfrench.com/grammar/sans/#:~:text=Sans%20is%20usually%20followed%20directly,with%20no%20article%20in%20between.

Sans is usually followed directly by a noun, with no article in between

[EvaZelen1]

Why this could not be translated simply as " I won't be able to climb up ....etc"?

[waakak]

In reality it could be, but Duolingo usually likes to preserve tense between the languages (they're very selective about applying this rule, however). In this sentence, it's more literal to translate it in the English near future since it's in the French futur proche.

[William402349]

....without ladders?

[InvertedGo]

Do you really need multiple ladders? Wouldn't it be difficult to use them all at the same time? Or maybe you'd be using them serially?

[AlfBarc]

This is such a weird structure....or je ne vais monter or je ne peut monter is a lot more realistic, I don't think people talk about "je ne vais pouvoir fer...." Maybe it's grammatically correct....but totally unuseful.

[Ronnie-JA]

Well, je ne vais monter is definitely incorrect when writing formally.
Even if we are being a bit more casual, surely it would be "je vais pas pouvoir ..." etc. The sentence does require recognition of ability to do something, so pouvoir is preferable if not essential.

Realistic "Je peux pas monter...".