OOC: No, you will have to try to evade the horse creatures somehow. They are coming in at an angle such that running to the jetcopter is also running toward them. Since it is less than a kilometer away, you could try running to the artifact or taking some other means. Bartja may be able to glide some.
Given the hungry dinosaur cat, your characters may be thinking that the safest place is inside the artifact.
Here's a diagram. Horses are running ESE according to this diagram.
<dinosaur>
<jetcopter>
<horses>>
<horses>> <you>
<horses>>
<artifact>