No GPS?
Instruction manual, page 18:
WARNING: Home Mode only works when the TYPHOON has a suitable
GPS signal/lock. If the TYPHOON loses GPS signal/lock it will switch to
Angle (Pilot) Mode automatically. This is why we strongly recommend
learning to fly in Angle (Pilot) Mode as soon as possible. Otherwise, if you
lose GPS signal/lock and are not able to properly control the TYPHOON in
Angle (Pilot) Mode the aircraft may crash or even ‘fly away’.