As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AFTER TAKEOFF AT APPROXIMATELY 200-250 FEET AGL THE ENGINE POWER DECREASED AND SUBSEQUENTLY WOULD NOT GO ABOVE IDLE. AIRCRAFT MADE AN EMERGENCY LANDING SAFELY PAST THE END OF THE RUNWAY IN A GRASSY AREA. TROUBLESHOOTING REVEALED CARBURETOR TO BE CONTAMINATED WITH A JELLY TYPE SUBSTANCE. CARBURETOR WAS REPLACED AND ALL ENGINE PERFORMANCE CHECKS WERE FOUND TO BE GOOD.