Failed to download HIL SIMULATOR

I try to upload Arduplane HIL stable, but I cannot upload it.
Please tell me the solution.

apm 2.6 or pixhawk?

pixhawk don’t have hil options

HIL is now builtin to all plane firmwares, for all board types.
Just load the normal firmware and then set the parameter HIL_MODE to 1. Then reboot
Don’t forget to change HIL_MODE back to 0 before flying a real aircraft!

Thanks a lot!!