GPDA director, Sebastian Vettel insists that lessons must be learned from Lando Norris' horrific crash in Q3.

Among the first out for the final phase of the session, despite being on full wets, Vettel advised his team: "They should red flag, too much water." "Quite a bit of aquaplaning," added Norris moments later.

Shortly after, the McLaren driver lost control exiting Eau Rouge into Raidillon, another horrific, violent incident at one of the sport's true black spots.

As Vettel headed down the hill from La Source, he was advised by his team to reduce speed due to Norris' crash.

"Yeah? Well what the f***- did I say?" he shouted. "What did I say!? Red flag! Unnecessary."

After asking if the youngster was OK, the German slowed alongside the wrecked McLaren where Norris gave him the thumbs up signal that he was alright.

Vettel's anger over the decision to allow the session to go ahead had not abated by the time he arrived back in the pits, and he immediately sought out race director, Michael Masi.

"I think Michael is not proud of what happened either," the German subsequently told Sky Sports. "It's always easy to play Captain Hindsight," he added. "I think we need to find a way that we listen more to the information that we have.

"Inside the garage, it's very limited, it's like looking out of a window... three kilometres that way, I have no clue. When I went down to Eau Rouge and up the hill, it was a lot of water and was calling for a red flag.

"The truth is, the session should not have started at all," he insisted. "I think the people that were standing on the Kemmel Straight, they were in the rain and maybe we should have listened to those."

Asked if he was angry at Masi for not stopping the session, Vettel said: "Angry, I think it's very difficult to be... it's always easy afterwards. The main thing is that we learn from what happened. It could have been a different outcome with the crash. I think we were lucky that nothing bad happened."

"There were things we could have done better," he added, "it's better to be safe one time too many than one time too little. It's good that nothing happened, that's the main news, but it could've been a different outcome for Lando. I'm not sure there is anything he could've done.

"Of course, we are in control and you can say 'if you feel unsafe, box'. But it's sort of a weird situation because everyone is in the same situation and you don't want to get kicked out, you want to progress. That decision shouldn't entirely be up to us.

"We delayed the session at the start when there was less water so I'm not entirely sure why we just didn't start the session. As I said, it's always easy afterwards, but the main thing is it doesn't happen again."

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