The other driver who missed the 105 per cent mark was HVM Racing's Simona de Silvestro, with her Lotus engine still not delivering the raw power needed for oval races. While both de Silvestro and Hildebrand will still be able to start the race (unlike the equivalent situation in F1), any car that still does not meet the 105 per cent cut-off int he opening laps will be ordered to park on safety grounds - as happened to de Silvestro early in the Indianapolis 500 last month.
Josef Newgarden was not able to post any time at all, after his Honda engine failed in the earlier practice session and the team was still working to install a new one. He will start at the back of the field on Saturday along with de Silvestro, and Mike Conway will also start ten places back from the 8th place he posted in Friday's session because of an engine change penalty at Belle Isle last weekend.
There was considerable debate up and down pit road about the levels of downforce available to the teams at Texas, with opinion seemingly divided between those lobbying for less downforce on safety grounds and those frustrated that it meant less chance of overtaking and side-by-side racing.
"We're on a bit of a mission as drivers to try to improve the safety of the series," said Penske's Ryan Briscoe, one of those drivers wanting to reduce downforce in order to ensure that the race doesn't become dominating by pack drafting. "We want to make the right steps towards making it safer and get it away from having cars running right on top of each other."
The ability of cars to run closely together in packs was one of the factors deemed to have contributed to the disastrous fatal accident at Las Vegas Motor Speedway last October, the last time that the IZOD IndyCar Series ran on a 1.5-mile high-banked oval track like Texas.
However, not everyone agreed with the approach.
"Everyone is freaking out about the pack racing," said owner-driver Ed Carpenter. "I'm lobbying hard for more downforce [or else] it's going to be a follow-the-leader, the most boring race we've ever had at Texas."
Rubens Barrichello - who posted a lap of 213.949mph (48.9650s) to claim 14th position on the grid for tomorrow's race - indicated that the drivers would meet with Beaux Barfield at the end of Friday to discuss the situation and hopefully agree a way forward.
But Dario Franchitti has experience of such situations in the past, and said, "Put 10 drivers together, they won't agree on anything," adding wryly: "Same as the owners."
There is a final practice session at 6.45pm local time, closer to the evening conditions that the race itself will actually be run in. That allows the teams and drivers to start setting up their cars for the cooler evening and nighttime conditions for the Firestone 550k. After that session, the circuit hosts this weekend's NASCAR Camping World Truck Series race on Friday evening.
Full qualifying times