Russia opened an investigation Friday after a passenger aircraft was forced to land due to a technical malfunction, the latest incident to highlight safety concerns in Moscow’s aviation industry. Sanctions over the conflict in Ukraine have effectively cut Russia off from Western plane manufacturers Airbus and Boeing, making it difficult for Russian airlines to import and maintain plane parts. The plane, a Boeing 737-800 operated by S7 airlines, was traveling from the Siberian city of Novosibirsk to Moscow on Friday before an engine failure forced it to turn back to the airport, investigators s…