As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AFTER TAKEOFF AND GEAR UP A LOUD RAPID KNOCKING FROM UNDER NOSE OF AC INCREASE IN SPEED NOISE LOUDER ALONG WITH KNOCKING. THE OPPOSITE EFFECT WITH DECREASE IN SPEED WITH GEAR DOWN NOISE AND KNOCKING STOPPED. JACKED AC AND SWUNG GEAR, FOUND GASPER FAN RCCB CLATTERING EXCESSIVELY. NO DISCREPANCIES NOTED WITH GEAR SYSTEM. OPS CHECKS GOOD ON GROUND.