Aldo Costa joined Mercedes as engineering director in 2011 © Sutton Images Enlarge

Former Ferrari technical director Aldo Costa says some of the blame for Ferrari's current failings should be put at the feet of president Luca di Montezemolo.

Costa was the man given the daunting task of replacing Ross Brawn as technical director for Ferrari but was sacked in 2011, and has since moved across to work for Mercedes. Costa thinks Ferrari's current problems stem from a multitude of errors made over a long term period.

"Strategic mistakes were made - I'm talking here about errors of vision - very serious ones," Costa told leading Italian F1 journalist Leo Turrini. "And of course they haven't always taken the best decisions regarding people. I'll give you an example: In 2008 we in the racing department put in a request to construct a new wind tunnel. We considered it essential to remain competitive. We were told that this was not the case and that there was no need.

"In Ferrari all the decisions, on strategy and people, have always been taken by the president, Montezemolo. To be fair, he took them when Ferrari was winning everything and he also took them when Ferrari stopped winning."

Costa, who says working at Mercedes is "professionally a happy time", thinks the contrasting manner of his dismissal in 2011 says a lot about Ferrari at the moment.

"I'm not happy about it. I worked for a company that is a myth. It doesn't please me to see how it is reduced, in Formula One terms, even though they fired me and in a way that I don't consider very elegant. Let me say that there are a lot of people working in Maranello, for whom I feel affection and it pains me that they are in such a complicated situation. It is not good, I left many friends there, should I be happy to see them in such trouble?"

Speaking of his time at Ferrari, Costa says it made him appreciate the talent of Fernando Alonso as a driver but admits he found the Spaniard a difficult man to fathom.

"I consider Fernando a true great when he is in the car, driving. Out of the car, I was never able to understand him; to me he is an indecipherable character, an enigma. However he will not be coming to us at Mercedes, I do not see why Hamilton should want to leave a team like ours."

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