Hi all! thanks for sharing the news! At Quaternium we are very excited to see that our project is raising so much interest! There are already many accurate comm

Hi all! thanks for sharing the news! At Quaternium we are very excited to see that our project is raising so much interest! There are already many accurate comments on this thread. But just to give you some context. Quaternium was the first company in the world to demonstrate a hybrid power system for a drone, with a flight over 3 hours back in 2015. Right now, our latest record is over 10 hours of hovering flight with HYBRiX multirotor (with an experimental setting with more fuel and no payload). A key element of this news is that the drone is <25 kg MTOW, (bigger aircrafts have obviously longer flight times). The fuel engine acts as a range-extender, it is a series hybrid, like the BMW i3. And we develop the power system, in collaboration with Löweheiser company (https://loweheiser.com/ https://loweheiser.com/) using a 2-stroke Zenoah engine that we adapt to the drone needs. Our product uses the engine on a very different duty-cycle, comparing to the standard application, so we do a lot of work on it and got a much better performance compared to other competitors. Multirotors are the most popular drones for several reasons, that some users have already mentioned. They are much more versatile because they can hover, do not need launching platforms and are quite easy to operate. They are also mechanically simpler than helicopters, reducing failure points. Our goal with HYBRiX is to being able to replace manned helicopters for aerial imaging operations, not to replace planes or fix-wings, which are more efficient for the applications that do not require hovering. As for convertible VTOLS / fix-wings, they are cool but not so versatile, because their hovering endurance is very limited, only useful for VTOL take-off / launch. That makes it possible to take-off from smaller areas than planes, but do not have a performance comparable to a multirotor. Hope this clarifies some doubts mentioned on the thread.