Top Gun

Obviously Top Gun Maverick was last year's best movie. If you were wondering if those aircraft were even possible: if not they will be. Hereus presents turbojet to ramjet in the same chassis. h/t toughSF

This blog, we admit, is more space-focused. Such speeds as might take a payload to LEO/exosphere skim are Mach 10+ so, maybe - scramjet. You'll be sending the freight to the hypersonics by whatever means; maybe railgun. If that jet needs to abort the mission it slows its jets and coasts; the main mission (to scramjet speeds) is over. Tho' we might hope to keep the booster; so single-shot ramjets might work for passenger flights.

Anyway if you are going from slow-to-scramjet: Hereus isn't your choice.

You need this engine, rather, if you are going from aeroplane-to-ramjet, and back again, and back again. That means military.