2017 American Formula 1 Grand Prix - Second free practice

21:31
We will be back for final practice at 11:00 local time tomorrow!
21:31
Stay tuned to the website for a full report, results, news and photos
21:31
We have a Mercedes, Red Bull and Ferrari in the top three!
21:31
Hamilton finishes on top, four-tenths clear of Verstappen
21:30
Out comes the chequered flag
21:30
Ferrari's session has been a little disjointed with Vettel's troubles
21:30
We not know fuel loads and exact run plans, of course
21:29
We have been keeping an eye on the lap times and it is looking pretty close between Mercedes and Red Bull in race trim
21:28
Vettel heads back out - let's hope the jelly has settled...
21:26
Hartley brings his session tally up to 38 laps - that's the joint-highest total, along with Hulkenberg
21:24
Ferrari took the seat out of Vettel's car in a bid to get to the bottom of the issue he reported on his latest run
21:23
It's still very busy out there - all bar Vettel, Hulkenberg and Ericsson are lapping
21:19
21:17
"It feels a bit like jelly at the front," reports Vettel, as he returns to the pits
21:15
Verstappen is expected to join them with PU changes of his own tomorrow
21:15
Vandoorne is one of three drivers, along with Hulkenberg and Hartley, who will take power unit-related grid penalties this weekend: https://www.gpupdate.net/en/f1-news/359977/grid-drops-for-hulkenberg-vandoorne-hartley/
21:15
Vandoorne has a big moment through the Esses - he catches the car and continues on his way
21:12
A breakdown of Hamilton's rapid lap on Ultra Softs:
21:11
Replays show Hulkenberg's car sparking through the Esses - teams are pushing the limits with ride heights, as usual
21:08
A change of tyres for Raikkonen, as he splits up his race run:
21:04
Vandoorne is told to avoid the sausage kerbs dotted around the track
21:02
Hartley, still getting to grips with Formula 1, locks up and runs deep into Turn 12
21:02
We're into the final half an hour in warm and sunny weather, the bulk of drivers working through long runs
21:00
20:59
Hamilton reports that he is getting some derates on this run
20:57
There's still a piece of bodywork sitting on the start/finish straight - as mentioned earlier, that came from Alonso's car
20:56
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20:55
Remember, you can check out the latest photos in our rolling gallery: https://www.gpupdate.net/en/f1-photos/15398/2017-american-formula-1-grand-prix-friday/
20:52
Most drivers have settled into longer runs now - the race will be in full swing at this time on Sunday afternoon
20:49
Stroll is the next to run wide at the penultimate corner
20:49
20:47
Only Sainz Jr. and Hulkenberg are yet to use Ultra Softs
20:47
Vettel has gone third, ahead of Bottas and Ricciardo
20:45
Replays show something flying off Alonso's car on the main straight
20:44
20:44
He would have been a little closer without that moment
20:43
...but still goes second, four-tenths slower than Hamilton
20:42
Verstappen runs very wide at the penultimate corner...
20:40
Alonso pops up to fifth position, between the Red Bulls - Ricciardo and Verstappen have yet to try the Ultra Softs
20:40
Raikkonen goes third, the best part of a second down on Hamilton's time
20:39
More drivers are making the switch to Ultra Softs now
20:37
20:36
Hamilton goes a second quicker than Bottas on the same tyre compound
20:35
20:33
Bottas duly goes quickest with a 1:35.596
20:33
Moments after we include that tweet, Bottas heads out on Ultra Softs
20:32
20:29
It's a truly incredible spot to watch a Formula 1 car in action - particularly the 2017-spec machines
20:28
Hulkenberg has the track to himself at the moment - he uses a healthy amount of kerb as he tackles the high-speed Esses
20:25
Vettel is the only driver without a time after that spin
20:22
20:19
"I think you saw that," he tells his engineer over the radio
20:19
Replays show Vettel's car getting away from him at the penultimate corner
20:19
He manages to keep the car moving, rejoins the track and pits
20:18
Vettel is in the gravel!
20:18
Verstappen's renewal with Red Bull is the big story of the day at COTA - he'll be staying at the team through 2020
20:17
Ricciardo made an improvement on his latest lap to leapfrog Verstappen
20:16
Verstappen, Hamilton and Alonso used Softs - the others Super Softs
20:15
Current top 10: RIC, VER, HAM, RAI, BOT, PER, OCO, VAN, ALO, SAI
20:14
Some drama at Haas...
20:13
Verstappen (Softs) and Ricciardo (Super Softs) form a Red Bull 1-2
20:10
Raikkonen, also on Super Softs, goes three-tenths quicker than Bottas - Hamilton, on Softs, slots into third position
20:09
Bottas, on Super Softs, moves to the front with a 1:36.976
20:07
20:07
He just about kept it out of the gravel and continued on his way
20:06
Replays show Magnussen going for a spin at the penultimate corner
20:06
Kvyat slots into second, from Hartley, Grosjean, Sainz Jr. and Magnussen
20:06
Remember, the FP1 benchmark was Hamilton's 1:36.335, posted on Super Softs
20:05
Alonso, on Softs, is the early leader with a 1:39.023
20:03
Hamilton is sporting a special USGP helmet:
20:02
Plenty more drivers are quick to emerge - fully dry conditions now
20:00
Kvyat is the first driver to hit the track - his first metres in a Formula 1 car since crashing out of the Singapore Grand Prix
20:00
Green light! FP2 begins
19:58
As it stands, air and track temperatures are 25°C and 29°C
19:55
Pascal Wehrlein will also get back in his Sauber, which was driven by Ferrari-backed Charles Leclerc earlier today
19:53
After Sean Gelael's FP1 run, Daniil Kvyat will return to action in FP2:
19:52
In terms of DRS, there are two zones in place - on the main straight and on the back straight
19:51
As a reminder, Pirelli has brought its Ultra Soft, Super Soft and Soft tyres here - the Ultra Soft is pink, rather than purple, as part of F1's push to raise breast cancer awareness
19:49
There is an interactive Facebook panel on the right-hande side of this page, while we can be found on Twitter via the @GPUpdate handle
19:48
Who will come out on top this weekend? And who will claim the title? Be sure to join in the discussion with fellow readers
19:46
Lewis Hamilton set the early pace, ahead of title rival Sebastian Vettel - remember, 59 points separate them, in the Briton's favour, with four races to run
19:45
Missed FP1? Here are the highlights...
19:44
After this morning's wet/dry opening session, conditions have improved, with blue sky breaking through the clouds!
19:43
Welcome to live coverage of second practice for the United States GP!