How does the elevator work on this UAV?

[Broncazonk]

Look at the first photo (click on it,) both rudders on this UAV are pressed up against the elevator and they have no inboard mechanical freedom at all. How does that work? What is this thing anyway, it's Israeli.

Bronc

 

[flateric]

they have no inboard mechanical freedom at all.

They have as elevator ends are cropped on Heron.

 

[chuck4]

Even if the elevator sides were not cropped, each rudder only being able to deflect to its own outboard side would still allow them to serve their purposes.

 

[Stargazer]

Look at the first photo (click on it,) both rudders on this UAV are pressed up against the elevator and they have no inboard mechanical freedom at all.

Wrong. It's an optical illusion. Look closer to the starboard rudder. You'll notice that despite the proximity of the elevator, you can still see some space at that angle. It means that if you look from the rear the space is even wider (the elevator's ends are slanted).

I'd say this configuration is pretty generic on all twin-boomers, and I think even aircraft with a regular tail configuration often have a similarly relatively limited latitude for the rudder. Nothing here strikes me as terribly unusual.

How does that work? What is this thing anyway, it's Israeli.

Do I sense a hint of condescendence in your words? It is an Israeli product indeed, an IAI Heron I think. Israel is one of the world's top leaders in UAVs... and don't you worry, I bet their designers know what they're doing!

 

[flateric]

Even if the elevator sides were not cropped, each rudder only being able to deflect to its own outboard side would still allow them to serve their purposes.

complicated controls+uneffective

 

[chuck4]

Even if the elevator sides were not cropped, each rudder only being able to deflect to its own outboard side would still allow them to serve their purposes.

complicated controls+uneffective

Not complicated if controlled through FBW. Yaw authority based on the substantial asymmetrical drag of deflecting just one of two widely spaced rudders is not necessarily less then conventional yaw authority of both rudders deflecting in unison.

But in this case the rudders are clearly designed to be able to deflect in unison.

 

[flateric]

of course we should install FBW on UAV instead of cropping tips on elevator...that's not complicated

 

[chuck4]

of course we should install FBW on UAV instead of cropping tips on elevator...that's not complicated

Given the cost of these UAVs it would be amazing if they didn't come with FBW.

 

[DWG]

of course we should install FBW on UAV instead of cropping tips on elevator...that's not complicated

Considering my next-door neighbour fits programmable auto-stabilisation systems on his metre-long remote control helicopters, there's probably no reason you couldn't squeeze one into a Heron
A long-endurance UAV pretty much needs a full blown autopilot/FBW flight control system, no matter how stable you make the airframe you don't want to be reliant on a pilot with hand on stick at the wrong end of a datalink to keep it in the air.
While I've no doubt the Heron's rudders operate in conventional fashion, there's no reason that twin rudders couldn't operate in an asymmetric fashion, that's pretty trivial to implement in a flight control system. In fact ISTR reading something, probably in the last year or so, about Boeing looking at using asymmetric spoiler deployment to answer some control issue on either 777 or 787.