Learn Spanish (Latin America): Me entristece que tú hayas sufrido un percance en el viaje. - It saddens me that you informal have suffered a mishap on the trip.

The phrase me entristece que (it saddens me that) is an emotion trigger, which requires the subjunctive. We use the present perfect subjunctive here because the emotional reaction is happening now in the present, but the mishap itself already happened and is completed. If you used sufras, it would mean 'It saddens me that you are suffering'.

Could I use the simple past indicative here, like Me entristece que sufriste?

No. In Spanish, main clauses expressing emotion (like me entristece que, me alegra que, or me molesta que) must always be followed by the subjunctive in the dependent clause. Using the indicative (sufriste) sounds grammatically incorrect to a native speaker in this structure, even though the event happened in the past.

Does tú have to be included before hayas?

No, it is completely optional. Hayas can only correspond to tú, so the subject is already obvious. Including the pronoun here simply adds a bit of personal emphasis or sympathy, making it feel more like 'It saddens me that you (specifically) had a mishap'.

How severe is a percance compared to an accident?

A percance is a setback, mishap, or minor accident. It is usually something unexpected and annoying, like losing your luggage or a delayed flight, rather than a full-blown tragedy. It is an excellent B2-level vocabulary word for describing travel issues!