Learn Swedish: Kämpande mot snöstormen fortsatte helikoptern räddningsaktionen. - Fighting the blizzard, the helicopter continued the rescue operation.

This is a reduced clause (satsförkortning). It replaces a full subordinate clause, such as Medan den kämpade mot snöstormen (While it fought the blizzard). Using the present participle kämpande to show two actions happening simultaneously makes the sentence more dynamic and is especially common in written Swedish.

Why is the word order fortsatte helikoptern instead of helikoptern fortsatte?

Even though the introductory phrase Kämpande mot snöstormen is a reduced clause without a subject of its own, it still counts as the first position in the main sentence. To satisfy the V2 (verb-second) rule, the main verb fortsatte must come immediately after it, pushing the subject helikoptern after the verb.

How do I know whether to use -ande or -ende to form this participle?

It depends on the verb's infinitive. Verbs that end in -a in their infinitive form (like kämpa) take -nde, resulting in the -ande ending (kämpande). Verbs that end in any other vowel (like bo or tro) take -ende, becoming boende or troende.

Why do we need the preposition mot here when the English translation is just "Fighting the blizzard"?