Стоит только изменить направление, как дротик попадает в другой сектор.

This is a common Russian pattern meaning:

• one only has to ... and ...
• as soon as ... , ... happens
• it takes only ... for ... to happen

So:

Стоит только изменить направление, как дротик попадает в другой сектор.

means something like:

• You only have to change the direction, and the dart lands in another sector.
• As soon as the direction is changed, the dart goes into another sector.

The idea is that one action immediately leads to another.

No. Here стоит is from стоить, not стоять.

Compare:

• стоять = to stand
• стоить = to cost, and in this structure also to be enough / to be worth / to only take

In стоит только изменить..., the verb is being used impersonally:

• стоит только сделать X = one only has to do X

So this is not about physically standing at all.

Because this is an impersonal construction. Russian often leaves the doer unspecified in patterns like this.

Стоит только изменить направление...
literally feels like: It only takes changing the direction...

It is very natural when the sentence expresses a general rule or typical result, rather than something tied to one specific person.

If needed, Russian can make the person explicit in other ways, but here the sentence is deliberately general:

• whenever the direction is changed, the dart ends up in another sector.

Изменить is perfective, and that fits well here because the sentence refers to a single completed change that triggers a result.

• изменить направление = to change the direction as a completed action
• изменять направление = to be changing / to change repeatedly

In this pattern, Russian often uses the perfective infinitive because it focuses on the action being carried out once, after which the next event happens.

So the logic is:

• make one change to the direction
• and the dart goes into another sector

Направление is the direct object of изменить:

• изменить что? → направление

That means it is in the accusative case. But since направление is a neuter inanimate noun, its accusative singular looks exactly like its nominative singular.

So:

• nominative: направление
• accusative: направление

Even though the form does not change, the function is still accusative.

Correct: here как does not mean how.

In this pattern, как is a conjunction meaning something like:

• and then
• when
• and immediately
• ... and as a result ...

It is part of the fixed structure:

• стоит только ..., как ...

So in this sentence, как introduces the result that follows immediately from the first action.

Because как introduces the second clause.

The sentence has two parts:

1. Стоит только изменить направление
2. как дротик попадает в другой сектор

Russian normally separates these clauses with a comma.

This punctuation is standard in the construction стоит только ..., как ....

Попадает is imperfective present tense, and here it expresses a general repeated result or a rule.

So the sense is:

• Whenever you change the direction, the dart ends up in another sector.

Russian often uses the present tense this way for general truths, demonstrations, instructions, or repeated behavior.

If the sentence were about one specific future event, попадёт could be possible in a different context:

• Стоит только изменить направление, как дротик попадёт в другой сектор.

That would sound more like:

• Just change the direction, and the dart will land in another sector.

But попадает makes it sound more like a regular principle.

Because aspect in Russian is not only about whether there is a result; it is also about how the speaker presents the event.

Here попадает is imperfective because the sentence describes what generally happens in such situations, not one single completed instance.

Compare:

• попадает = ends up landing / lands in a habitual or typical sense
• попадёт = will land in one specific future case
• попал = landed in one completed past case

So even though the action has an endpoint, the imperfective is natural because the sentence is about repeated predictable behavior.

Because the sentence describes motion into a sector.

With в:

• в + accusative = motion toward/into somewhere
• в + prepositional = location inside somewhere

So:

• в другой сектор = into another sector
• в другом секторе = in another sector

Since the dart is moving and ending up in a different area, Russian uses в другой сектор.

Here другой means another or a different.

So:

• в другой сектор = into another sector
• into a different sector

It implies a change from one sector to a different one.

Дротик means dart.

It is a masculine noun. In this sentence it likely refers to a dart moving into a different sector, possibly in a target-like setup or some technical/modeling context.

Its basic forms are:

• nominative singular: дротик
• accusative singular: дротик for an inanimate object

Here it is the subject of попадает.

The word order is natural and emphasizes the trigger first, then the result:

• Стоит только изменить направление, как ...
• One only has to change the direction, and then ...

This order works well because Russian often puts the condition or triggering action first.

You could rearrange things in other contexts, but this version is very idiomatic and clear. It highlights the cause-and-effect relationship.

Not very naturally. A word-for-word translation would sound awkward in English.

Roughly:

• Стоит только = it is enough only / one only has to
• изменить направление = to change the direction
• как = and then / when
• дротик попадает в другой сектор = the dart lands in another sector

A natural English translation is better than a literal one, because стоит только ..., как ... is a set Russian pattern rather than something English mirrors exactly word for word.