Naturally fingers are being pointed at Israel following the exchange of drone/missile strikes last month. Apparently the chopper made a hard landing, so currently not much can be surmised beyond that.
But Iranian aircraft, particularly Western-supplied models such as the US-made Bell 212 helicopter carrying Raisi, are notoriously unsafe and in a state of disrepair as the Islamic Republic has long been subject to Western sanctions that prevent access to desperately needed spare parts.
https://www.dailymail.co.uk/news/ar...e-Islamic-regime-supports-Hamas-Gaza-war.html.
Giveth and taketh away I guess.