A maintanence test is to blame for 5 E-8 Jstars receiving damage while on the ground,a single engine failure during maintanence test sent debris flying across the field into the the other aircraft.Most received minor damaged were repaired and back in service within 2 days,however one aircraft received more severe damage and will not be back in service until after the first of year.Fortunately during the incident,none of the canoe pods were damaged on any of the aircraft.