Poor bonding to blame for errant winglets admits Haas team boss.

It's fair to say that today's opening day of its first home Grand prix weekend was a bit of a let-down, if not a major embarrassment for Haas.

Perhaps the day was best summed up by the moment near the end of FP1 when both cars lined up at the end of the pitlane to perform practice starts but subsequently had to be rescued and pushed back to their garages.

And while Red Bull claims to give you wings, the American outfit had great difficulty holding on to theirs, both Romain Grosjean and Esteban Gutierrez losing winglets over the course of the two sessions resulting in the deployment of the VSC and even a red flag.

"We didn't do good today," admitted team boss Guenther Steiner. "We need to do better tomorrow because we had a few issues with some rear winglets breaking off. It happened three or four times, always the winglet, but we realise now what it is and we'll fix it for tomorrow.

Much like Sebastian Vettel's mirror, which was seen to come lose after a ride over the circuit's unforgiving kerbs damaged a vane, the Haas duo also suffered after running wide.

"It seems like the vibration meant they broke off where they are bonded, so we need to make a mechanical fix and then a better part for the future," he said.

Referring to the moment at the end of FP1 when both cars needed to be rescued, the Italian said: "One stalled and the other couldn't find reverse, so we pushed them both back in. Nothing dramatic, it was just a mapping issue on the engine side, the first stalled, and the second one we did for safety reasons instead of Romain trying to engage a gear and breaking the box.

"To add to this, there was also a general lack of overall performance," he admitted. "We know where to go, but the lack of stable running doesn't help to find performance and the set-up. That's the biggest problem we've got, so with the engineers and the limited amount of data we've got we need to find a solution for FP3."

Check out our Friday gallery from Austin, here.