Her racing helmet is a touching tribute to her Isle of Lewis home: the colours reflect the turquoise waters of Tolsta Beach, inky black night skies dotted with shimmering stars, a splash of tartan and her personal mantra – ‘Just keep going’.

As Isla Mackenzie puts her foot to the floor and races around the iconic Silverstone race track, the spirits of her two late grandfathers and a dearly departed close friend are in her sights – their names are stuck onto the inside frame of her car.

With a need for speed that defies the rather more sedate image of her Stornoway crofting roots and having physically pushed her slight frame to cope with the rigours of racing, she has now entered a crucial lap in her own ‘drive to succeed’ bid for F3 glory.

And, it turns out, the motto on her helmet – ‘just keep going’ – could scarcely be more pertinent.

One of a handful of women to work behind the scenes in the exclusive world of F1 engineering, the determined 29-year-old’s hopes of becoming a professional racing driver have been captured in a powerful documentary, which reveals the adrenalin-fuelled highs and multiple lows of trying to take the chequered flag.

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Filmed as she prepares for her first races in her new deep blue single seat racing car, with its patriotic saltire, her number 11 and her name emblazoned on the side, there is the excitement of tackling Silverstone’s world-famous Silverstone corners, and the brutal disappointment as her hopes of competing come crashing down.

And, as the film shows, succeeding as a young woman in the high stakes and high-cost world of motor racing takes more than passion, driving skill and hours of strenuous training - it also requires cold, hard cash and a very thick skin.

The Herald: Isla Mackenzie grew up riding horses on the beaches of the Outer Hebrides. Isla Mackenzie grew up riding horses on the beaches of the Outer Hebrides. (Image: Credit: Isla Mackenzie)

Screened this Friday on BBC One, Fast Track to Glory, made by Stornoway-based Mac TV and directed by award-winning director, Daibhidh Martin, is part of the channel’s acclaimed Our Lives series, which tells stories of people across Britain pursuing extraordinary dreams, overcoming odds or coming together to achieve remarkable accomplishments.

It tracks Isla’s story from growing up in the rural idyll of the Outer Hebrides where she honed her love for speed first by riding horses on the sweeping sands of her favourite beach, to careering over bumpy farm tracks on a quad bike and getting behind the wheel of her first Ford Fiesta.

The wild beauty of the island is in stark contrast to the sleek surroundings of the Mercedes-AMG Petronas F1 Team factory, where she is one of a handful of dyno technicians working on Sir Lewis Hamilton and teammate George Russell’s cars and dreams of making the leap from karts to racing cars.

Her that seemed suddenly achievable after she was talent spotted by racing team, IMC Motorsport, to race in the Monoposto Formula 3 championship, while continuing her full season behind the wheel of Senior Rotax (karts) in the IKR Championship, competing of karting tracks where Lewis Hamilton honed his skills.

While training for both pushes her physically and occupies almost all her spare time, the film reveals blow after blow as her hopes to race  at Silverstone and then at Donnington are cruelly dashed by a string of technical issues.

With just a handful of races left this season, time as well as finances are now stretched if she is to make her F3 debut this year.

Now back home on holiday while the F1 season halts for summer, Isla says she is now considering what next – and whether her future lies even further from her family’s Stornoway home and instead, in the fierce, high-octane world of US IndyCar racing.

“I was ready, but unfortunately for Silverstone and Donnington the car was not ready for racing,” she says.

“I’ve got options and I’m not rushing into the remainder of the season. I’m going back to karting after my holiday and Formula 3 is TBC – to be confirmed.

“The reality is that I think can still compete, but there might come a point where I think I have to let this season go.”

The Herald: Isla Mackenzie is featured on BBC One's Our Lives series. Isla Mackenzie is featured on BBC One's Our Lives series. (Image: Credit: Isla Mackenzie)

But, she adds, she is not giving up on her dreams yet.

“I think it’s definitely going to happen though - if not this year, then next year.

“I’m very determined, although there have been lots of highs and lows in this journey.

“But I sit here thinking how lucky I am that I have a documentary coming out that and who knows who will see my story and what I’m trying to achieve? I’m optimistic.”

Although hooked on the thrill of speed – from quads to karts – Isla had originally planned to study zoology, only to arrive at university and realise she had made a mistake.

When she switched courses to study for an HNC in engineering systems at a local college, she realised that, despite being the only female on the course, she had found her niche.

At just 23 was picked to become the first female technician in F1 team Williams’ Prototype and Test department, but as the programme shows, there have been a string of challenges to overcome – from challenging sexist perceptions over women working and participating in motor racing to the sheer expense involved in taking part.

“When other women approach me it’s hard because I don’t want to say it’s all amazing,” she says. “It has been tough in some instances.

“The trouble is not everybody thinks a woman’s place is in motorsport or engineering.

“It’s better than it was, but the fact I’ve had some bad times means I’m better prepared for it. I just don’t care any more.”

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When her Donnington race hopes collapse, however, Isla’s tough shell cracks and she is seen fighting back tears as she explains that, along with the disappointment, is the loss of more than £500 she had paid to be there.

While the costs associated with racing – and the financial hit should the car sustain damage – have a direct impact on performance, with Isla conscious of holding back on the track for fear a bump could prove costly.

The Herald: Isla is now considering entering the world of IndyCar racing. Isla is now considering entering the world of IndyCar racing. (Image: Credit: Isla Mackenzie)

Yet despite it all, she says she remains hopeful of becoming a professional racing driver, possibly taking her skills to the United States of America where there is a thriving community of high level women drivers and the opportunity of taking part in the huge NTT IndyCar Series.

“I’m lucky to have faced most of the challenges in my engineering journey, and it prepared me to have a thicker skin when it came to racing side,” she adds.

“Women get paid to race in the US, that’s where I am aiming for,” she adds.

“And I’d love to be associated with some kind of motorsport team whether that’s F1 or another high-level motor sport perhaps as a racing ambassador for a team pushing women in engineering and women in racing,” she adds.

“I have big dreams.”

Fast Track to Glory: Our Lives is on BBC One on Friday, August 11, at 7.30pm