Go to the "Research by Subject" tab on the Library's home page. Then choose "Mechanical Engineering."
You can go to the "Mechanical Engineering Research Guide" and search using the "Find Books" or "Find Articles" tabs.
Or, you go right to the "Core Resources" and choose Applied Science & Technology and Computers & Applied Sciences Complete databases.
Try to come up with a list of search terms before you begin your search. For instance, you might use "aircraft" or "airplanes" or "aviation"coupled with "hydrogen" and be able to find something under each. Will the hydrogen power a jet engine? Then use "jet engine" as a search term, too. Here you can find suggested Library databases for where to search for articles. In this case, you can find a number of articles on your topic in both of these databases.