Though it was the actress and Gurkha campaigner's first visit to the country from which the fearless warriors originate, locals described it as a "homecoming".
Such was the excitement that it took the Absolutely Fabulous star more than 15 minutes to make her way the short distance through the crowd out of the terminal.
Many well-wishers waved Union flags and carried placards with the words "daughter of Nepal" and "thank you".
Other banners said "Ayo Goddess Joanna" in an echo of the traditional war cry "Ayo Gurkhali!" – meaning "the Gurkhas are coming!".
It's a slogan Joanna has used many times in her high-profile battle to win the right for former Gurkha soldiers to settle in Britain after serving with the British Army.
And after emerging from the intense crush she stood in the doorway of her car to greet the throng of delighted supporters with that time-honoured cry.
"It's a very warm welcome. I'm very emotional. If it wasn't for a Gurkha who saved my father's life I'd never have been born, which is a grim thought," said the 62-year-old.
Joanna, the daughter of a British Army officer who fought in Burma alongside Gurkha troops during the Second World War, initially began her fight because her father would have been "overwhelmed with shame" at their treatment.