The Prince of Wales will visit the Bombardier train-building factory and Rolls-Royce later today to show support for British manufacturing.
Charles will be given a tour of Bombardier and meet members of the workforce at the plant in Litchurch Lane, Derby.
He will then go on to Rolls-Royce where he will view the aero-engineering production assembly area before meeting apprentices.
Bombardier has endured a period of uncertainty after the firm lost a lucrative Government contract to build new trains, which was awarded to Germany company Siemens.
The firm has guaranteed the short term future of the Derby factory, although union officials fear jobs could still be lost unless new contracts are won.
Bombardier is the sole producer of trains in the country. It employs around 3,250 people at production facilities in Derby and Plymouth and 39 centres across the UK.
The firm is responsible for the maintenance of some 5,200 vehicles in the UK.
Speaking ahead of today's visit to Derbyshire, union leaders said it would be "great boost" to the workforce.
Unite assistant general secretary Diana Holland said: "We welcome Prince Charles' support for British manufacturing and British skills. This visit will be a great boost for the workforce who have had to endure a lot of uncertainty over the last 12 months.
"It would be nice if Prince Charles announced that the royal family wanted to commission a new royal train. Not only could it be used by the Royal family but it could be used for the benefit of the nation.
"Clearly one train won't support the Bombardier factory in the long-term, but it will be a recognition of the skills of the workforce and their ability to build state-of-the-art trains."
Unite said it was "crucial" that Bombardier wins orders for the Crossrail project through central London.
Meanwhile, Rolls-Royce is set to open a new state-of-the-art Apprenticeship Academy in Derby this year, allowing the company to train up to 200 additional apprentices.
The company, which employs some 21,000 in the UK including 12,000 people in the Derby area, already takes on around 200 apprentices each year and also runs a young apprenticeship scheme.
Last year it invested £908 million in research and development, two thirds of which had the objective of further improving the environmental performance of its products, in particular reducing emissions.
It customer base includes more than 500 airlines, 4,000 corporate and utility aircraft and helicopter operators, 160 armed forces, more than 4,000 marine customers, including 70 navies, and energy customers in nearly 80 countries.
The Prince will round off his visit to Derbyshire by visiting Haddon Hall and Gardens in Bakewell to look at restoration work that has taken place.
Last year the Fountain Terrace was restored and the Bowling and Orchard terrace will be the focus of restoration efforts over the next two years.
The areas around the Hall, which are not contained within the terraced gardens, are being reclaimed as wildflower meadows, which will include reintroducing the almost extinct native Derbyshire orchids.
Charles will meet supporters and long-serving volunteers from the Hall and the Peak District National Park Authority at a reception.Suggest a correction