I've just finished writing a book about the Viscount and in the course of this, I've come across a number of unexplained accidents in which the type was involved, including one of which I witnessed myself. (G-AMOL at Speke).
I find it odd that Aer LIngus' maintenance would be questioned. I worked a lot with them in the 60s and 70s, including numerous trips to Dublin, and although I'm not n engineer, I always thought their maintenance to be very good. Lingus also lost a Viscount on a training flight under mysterious circumstances:
