Looking on the internet deeply has found these results:

the train was going at full speed is the most popular phrase on the web.

the train was going in full speed 10 results on the web	the train was going at full speed 123 results on the web More popular!
Some examples and use cases from the internet:	Some examples and use cases from the internet:
It doesn't look like this phrase is very popular! The search could not find any examples on the internet.	... while the train was going at full speed, or performed any of the other little stunts which Cleo Madison undertook as all in the day's work during the filming of the�... Jul 3, 2005 ... But nobody jumped. The train was going at full speed with no stops. Even the bigger stations were ignored and we went fast towards the west. Oct 26, 2015 ... Many have said that the train was going at full speed, but if that had been the case the result would have been much worse," said Hedstr�m. Dec 20, 2007 ... Scroll down for more... He said: "The train was going at full speed. Then there was a sudden jerk and we felt the train sinking into the earth.

the train was going in full speed

10 results on the web

the train was going at full speed

123 results on the web

More popular!

It doesn't look like this phrase is very popular! The search could not find any examples on the internet.

... while the train was going at full speed, or performed any of the other little stunts which Cleo Madison undertook as all in the day's work during the filming of the�...
Jul 3, 2005 ... But nobody jumped. The train was going at full speed with no stops. Even the bigger stations were ignored and we went fast towards the west.
Oct 26, 2015 ... Many have said that the train was going at full speed, but if that had been the case the result would have been much worse," said Hedstr�m.
Dec 20, 2007 ... Scroll down for more... He said: "The train was going at full speed. Then there was a sudden jerk and we felt the train sinking into the earth.