Power's incident was the third of the day after 2016 Indianapolis 500 winner Alexander Rossi spun on the warm-up lane and four-time defending Indy winner Helio Castroneves spun out of the warm-up lane into the Turn 2 wall, prompting the test to be prematurely concluded.
The 2018 Indy 500 winner completed a 360-degree spin on the strip of grass that separates Turn 1 from pitlane exit. As he gathered up his Team Penske machine, its rear hung over the racing line at the apex of Turn 1 when Herta arrived on the scene.
The Andretti Autosport driver moved up half a lane to avoid contact, but that put his car into a drift that became a spin. Herta’s car tagged the outside wall with its rear wing, and slid broadside with wheels locked down to the inside of Turn 2, where he was narrowly avoided by a closely following Marcus Ericsson.
Power said that the incident “scared the absolute daylights out of me” and brought to mind Alex Zanardi’s life-changing accident at Lausitzring in 2001 when the Italian spun exiting the pits and was hit at full speed by Alex Tagliani.
“Scary, scary,” Power said. “It’s like my worst nightmare.
“It’s something you always think about as a driver because you’ve seen it. You saw what happened to Zanardi and it’s just something you’re aware of, and you’re cautious of during practice, and I just couldn’t believe it caught me out.”
Power explained that he had “zero warning” that his car was about to break away having “been taking it easy on the apron” after the day's earlier incidents.
“I told the engineer, ‘Look at the video, we’ve got to understand what happened there, because I don’t understand what happened,’” said the Australian.
“It’s just a bad situation. I want to know what I did wrong because I never want that to happen again.
“I don’t know if it’s something on the track because it felt like water. As soon as I finished spinning, I thought, ‘Man, there must be water there – something – because I’ve been out of that pitlane hundreds of times.
“It just surprised me, big time. Normally you’re ready for that stuff when you’ve had a whole career; you get some warning.
“I feel terrible for Colton to have to crash because of something that happened there by me.”
Power said IndyCar was right to call an end to the action for the day.
“Let’s really review the video and have a look at the track,” he said.
“I’m sure the [IndyCar officials] have inspected it to make sure there’s not a weeper or something. Because I asked my guys, ‘Did I hit the grass, did I hit the grass on the inside?’ And they said, ‘No, no’. It just looked like it went like that with zero warning.”
Castroneves explained that his Turn 2 impact aboard last year's winning Meyer Shank Racing machine was “very strange”.
“Talking to other drivers, like Colton, he said it almost happened to him too but he saved it,” said the Brazilian veteran.
“Very strange, not sure if it's because the temperature dropped just now.
Car of Helio Castroneves, Meyer Shank Racing-Honda after his crash
"I wasn't pushing, I wasn't even trying. Honestly we were just trying stuff on the track to make sure the car felt good.
“It was very unusual. You saw me looking at the car, I was like 'I can't believe it! What happened?’
“A driver has the knowledge, if you're trying to push, or do something different, but I'm not sure what happened."
Scott Dixon topped the speed charts for Chip Ganassi Racing, the 2008 Indy 500 winner turning a 227.187mph lap to finish up ahead of Conor Daly’s Ed Carpenter Racing-Chevrolet.
Although the foreshortened track time meant lap speeds were largely inconclusive, Juncos Hollinger Racing could be highly satisfied that its rookie Callum Ilott was third fastest in the 226mph speed bracket. The former Formula 2 ace had also topped the rookie and refreshers course, which also featured two-time Indy 500 winner Juan Pablo Montoya (Arrow McLaren SP-Chevrolet) and 2006 Indy 500 runner-up Marco Andretti.
Santino Ferrucci was fourth fastest for Dreyer & Reinbold Racing, ahead of Ganassi’s Ericsson and Rossi.
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