As the flight approached Grozny, it entered thick fog, surviving passengers say.
They describe the pilot attempting to land the plane twice during these conditions.
It was on the third attempt, survivors say, that they felt a series of explosions hit the plane.
“The third time, something exploded… some of the aircraft’s skin had blown out,” one told Russian TV.
A flight attendant on the plane, Zulfuqar Asadov, told local media the impact of the strike “caused panic inside”.
“We tried to calm [the passengers] down, to get them seated. At that moment, there was another strike, and my arm was injured,” he said.
A video filmed in flight by a passenger showed oxygen masks hanging from the ceiling.
Azerbaijan’s transport minister Rashad Nabiyev said: “All [the survivors] without exception stated they heard three blast sounds when the aircraft was above Grozny.”
He said the plane was subjected to “external interference” and damaged inside and out as it tried to land.
In recent weeks, Ukraine has been targeting Chechnya and other parts of the Russian Caucasus with drone strikes.
After the crash, authorities in Moscow said such attacks had triggered a protocol to close the airspace above Grozny.
According to local officials, a drone was shot down by air defence above a shopping mall in Vladikavkaz, in nearby North Ossetia, that morning.
It is unclear whether the closed-airspace protocol – known as a “carpet plan” – was enacted before or while Flight J2-8243 was in Russian air space.