Earlier discovery of balloon flight

[cloistered scholar]

It really seems like something that could have been in use hundreds of years before it's eventual discovery.

Let's say balloons capable of carrying human passengers is invented in China between 1200 ce. The Mongol Khans spread the idea with there armies across eurasia.

How useful is military reconnaissance from ballons? Could airships work without internal combustion engines?

 

[PecuTheGreat]

So something like this?.

 

[Pesterfield]

Could airships work without internal combustion engines?

You'd need to understand air currents and how to get into one going a direction you want.

How useful is military reconnaissance from ballons?

A higher vantage point is always good, with telescopes even better. The problem is getting the information back down to the ground.
Either return and land or have some signaling device.

Or if you just go up but stay behind friendly lines dropping messages could work fine.

 

[Dathi THorfinnsson]

Mongolfier balloons sure seem to have been possible much, much earlier. So, yeah, tethered balloons for observation make sense.

As pointed out, communication with the ground is a problem , but a surmountable one.
Telescopes vastly improve the usefulness, but they should be usable without them.

The support infrastructure needed is significant. You ve got to know where the battle will be, and get the balloon there, firstly, then filled and up in the air. All that requires a fairly static battle - which many are, but many aren't, and you don't necessarily know which it will be ahead of time.
If the enemy win, or even just press to the balloon tether base you lose a very expensive balloon and skilled operators.

The basket and balloon envelope will be heavy and unwieldy, and any wagons used for it won't be carrying food or other military supplies.

Tlr
Definitely useful in the right circumstances, but there are a lot of constraints.