A motorcyclist appeared to grab his front brake as a US servicewoman emerged from a junction across his path, before he struck her car and was fatally injured, a court has heard.

Airman first class Mikayla Hayes, 25, pulled out to turn right when motorcyclist Matthew Day was “10 to 15 metres” from her car, according to the testimony of witness Graeme Pratt.

Father-of-one Mr Day, who was travelling south on the A10 on a red-and-white Yamaha motorbike, collided with the defendant’s maroon-coloured Honda Accord on August 26 last year.

The 33-year-old died of his injuries later that day, Norwich Crown Court was told.

Hayes, who had been travelling from RAF Lakenheath in Suffolk to her home in Downham Market in Norfolk, had emerged from the B1160 Lynn Road turning right onto the A10 at Southery in Norfolk.

She denies causing Mr Day’s death by careless driving.

Mr Pratt was riding his motorbike behind the Honda driven by Hayes as it approached the junction with the A10.

He told the court that the Honda was being driven “normally, it wasn’t veering across the road”.

Mr Pratt said that at the junction “I pulled up behind the car, it sat there – I could see the person in the driver’s seat looking both ways”.

He said: “There was heavy traffic – they just sat there looking.”

Mr Pratt said it “felt like four or five minutes sat there waiting to get out, that would be an estimate”, adding: “It felt a long time.”

He said a car travelling south on the A10 indicated left to turn off at the Southery junction, the motorbike was behind it and “my thought process was once that bike was past us there was sufficient gap for both of us to get out”.

“I recall the Honda moving forward, I stayed where I was, I looked up and I could see the Honda pulling out and the motorcycle still travelling down the A10,” he said.

Asked by prosecutor Rachel Scott what the gap between the motorcycle and the Honda was when the car moved forward, he replied: “I would estimate as 10 to 15 metres.”

Questioned about what the motorbike did as the Honda moved forward, Mr Pratt said: “I’m presuming the rider grabbed the front brake – I watched the front of the bike dip, which is normally pulling the front brake.”

Asked how soon after the Honda pulled out he saw the bike dip, he replied: “Seconds, I couldn’t give an exact time.”

It happened so fast. I didn’t register any real time between the car moving off and the motorcyclist hitting the car

He said that as he saw the Honda move forward “I shouted ‘no’ in my helmet”.

“It was a reaction,” he said. “I was shouting ‘no’ to the woman to stop, I could see what was going to happen.”

He said that when the Honda moved forward “there was no urgency to fly across the road”.

Mr Pratt said he saw the Yamaha motorbike strike the side of the Honda, with the bike and rider thrown into the air.

Driver Derek Cummings, who was also queuing for the junction and witnessed the collision, said: “It happened so fast.

“I didn’t register any real time between the car moving off and the motorcyclist hitting the car.”

He said he asked the woman in the Honda if she was hurt and she “pointed to her head and suggested she had hurt her head”.

Mr Cummings added that the woman was “clearly very upset, very emotional”.

Gary Pammenter, a driver who stopped to help after the crash, said he asked Hayes if she was injured and she said her “neck was hurting and her right temple”.

“I initially spoke to her to try to calm her down, then when she said about her head I held her head to prevent any movement,” he said.

Mr Pammenter said she was wearing US Air Force physical training kit, a grey T-shirt and blue tracksuit bottoms with the Air Force crest on, and he told her he was ex-RAF.

“She told me she was a mechanic, she told me she was based at RAF Lakenheath,” he said.

Mr Pammenter said she told him she had been “over here for approximately three months”.

“She asked me if somebody could let her husband know,” he said.

Mr Pammenter said she “kept repeating ‘I didn’t see him, I looked and didn’t see him’”.

“I asked what she could remember in case anything had happened – she said ‘I stopped, I looked and I didn’t see him’.”

He said she was “crying”.

I wouldn’t describe Matthew as a risk taker and he would wait for gaps in traffic to overtake, for example

Driver Leona Palmer said she was travelling south on the A10 and when she indicated left for the Southery junction, the motorbike behind her carried straight on.

“I saw a car come from the Southery turning turn right and I just saw a lady in a red car and she was flapping her hands,” she told jurors.

“I thought ‘what’s happened?’

“I had my radio on, I think I heard a bang but I can’t be certain.”

She said she stopped her car and went to “reassure” the motorcyclist in the road, putting a sheet over his leg which was in a “terrible state”.

She said the motorbike had stayed behind her while she was on the A10, adding: “I don’t think we got up to 60mph as there was a bit of traffic.”

Mr Day’s partner Jenny Smith said, in a statement read by the prosecutor, that she had been with him for four-and-a-half years and “ever since I knew Matthew he rode motorbikes”.

She described him as a “good rider”, adding: “I wouldn’t describe Matthew as a risk taker and he would wait for gaps in traffic to overtake, for example.”

She said she was aware that he smoked cannabis, describing him as a “casual user”, and said she did not know when he last smoked the drug.

The trial continues.