I tried asking this before but I don't think I sent it correctly.
My question was, due to my novel I am using several vehicles and was curious as to whether I can mention their makes. E.g. one of my characters drives a sports car whilst another uses an army truck. Also is the same for aircrafts as well? I am just concerned about copyrighting issues.
Many thanks. Answer:
It's not a question of copyright, but of the trademark a manufacturer has on the name of its products. Trademark is designed to prevent one company from capitalizing on another company's brand. Companies protect the reputation of their trademarks.
However, you are generally free to use trademarked names of products in your fiction if you use them correctly (for instance, don't call a sports coupe a Range Rover or refer to all online searching as "googling"). Companies usually don't mind their products being mentioned because this actually gives them free advertising in your book (similar to product placement in films). It helps them in their effort to make their products into household names. (The difference is that I have never heard of a novelist getting a fee for using the name of a company product in a book, though film companies will sometimes get fees for product placement).
The other thing to avoid is saying anything defamatory about trademarked products. For instance, if you have a character, who is a mechanic, going on at length about how Company X hasn't made a decent car since 1983 and a person would have to be a sucker to buy one, Company X might take issue with that. Even if that's your honest and expert opinion, you're writing a novel not a product review.
Of course, if you want to have a company in your book that makes terrible cars, you can simply invent a fictitious company. That is the best choice if the company plays a major role in the story. If the company or its products are just part of the landscape, specified for the sake of authenticity, you are likely safe.
(As always, I should remind you that I am not a solicitor and if you think you are in a grey area with a book that is expected to sell like hotcakes, you or your publisher might want to consult one.)