Vettel returned to the cockpit in Melbourne after missing the opening two races of the season due to COVID-19, with Nico Hulkenberg stepping in as his replacement.
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Four-time world champion Vettel crashed in FP3, compromising his qualifying session, and then went off again early in the race. His team-mate mate Lance Stroll also hit the barriers in FP3.
Krack insists the incidents were not due to the German missing the previous races and thus lacking cockpit time, and admits the team has to take responsibility for the behaviour of the car underneath him.
“I'm happy that Seb is fine first of all, after all these incidents,” said Krack.
“But I think if someone like him, a four-time world champion, has these issues that he was having this weekend, this is not down to not driving - because he has driven the car.
“This is something that we need to really look at, what car we provide him, what feedback he gets from the car. Because you will agree with me that him being off so much as he has been this weekend is not normal.
“And I do not think that this is related to having missed two races. I mean, he has been a multiple winner in Melbourne. He knows where he is here. He has had some tests with the car.
"So I think it will be really easy to say, ‘Ah, he was not there for two weekends.’ A driver of that class, we really need to check what tool we are giving him.”
Krack says that Aston Martin knows why it has not been competitive so far this year, with the team languishing in 10th place in the championship having failed to score a point in 2022.
“In F1, if you're not performing, it's normally quite easy to identify,” said Krack.
“The reasons why teams are performing and others are not are lying with aerodynamics and car weight at the moment.
"So, while we make progress on the weight side, we struggle on aerodynamics. So this is something we need to really focus on.
“I don't want to go into the complete detail, but the reasons for the performance are normally in that area, and for us, it's the same. And then everything becomes much more difficult.
“So the better aero you have, the easier everything gets, the drivers are happy, the results are better, so everything gets easier. And, if not, you put everything in doubt.”
Asked if the team had gone the wrong way when developing the AMR22, he added: “I think there was a decision on concept at a certain point, and how you have to operate the car.
"And you see the issues that we're having around porpoising or oscillations like other teams are having, and this is a little bit the thing that does not allow us to move forward.
“We make progress, but to exploit it, we go to this barrier of porpoising, which does not allow us to exploit the progress that the guys have made.
"So it's quite frustrating also, that you know you have progress down the line, but you cannot exploit it on track.”