Portable Ferris Wheel With a Cracked Tower Weld
You are a mechanic working for a ride owner at a county fair. A portable Ferris wheel has 12 gondolas, hydraulic drive, and a 60-ft tower. During a pre-opening inspection you find a 2-in. crack in a weld at the base of the No. 3 tower leg, a missing cotter pin on one gondola's restraint latch, and a daily inspection log that has not been signed for three days. The ride is scheduled to open in 45 minutes, and the operator says the crack has been there since last season. Wind forecast is 30 mph gusting to 40 mph; the manufacturer's operating manual limits operation to 25 mph. The ride has a current annual permit.
1. What immediate action should you take, and who must be notified?
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Stop the ride and keep it closed. Clear the queue and barricade the entrance. The cracked tower-leg weld is a structural defect, the missing cotter pin affects a restraint latch, the inspection log gap shows the daily checks were not performed, and the wind forecast exceeds the manufacturer's limit. Notify the ride owner and the IDHS State Fire Marshal Elevator and Amusement Ride Safety Section. Do not accept the operator's statement that the crack is old; a known crack still requires engineering evaluation. Document the crack length, location, log gap, and wind readings before any repair or movement.
2. What repair and verification should be required before the ride can reopen?
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The tower-leg weld requires evaluation and repair by a qualified welder under the manufacturer's or a engineer's direction, followed by the required inspection method, such as nondestructive testing, before the leg is loaded. Replace the missing cotter pin and inspect the restraint latch on that gondola and the matching hardware on the others. Review why daily inspections were missed and correct the records. Do not permit a field weld by unqualified personnel or a simple cotter-pin replacement to close out the structural issue. The owner must provide repair documentation and the ride must be retested.
3. What conditions must be met before the ride carries passengers again?
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The structural repair must be completed and accepted, the restraint hardware must be correct on every gondola, and the daily inspection must be current and signed. The wind must be within the manufacturer's limit at opening and monitored during operation. Confirm that any required reinspection or notification to the State Fire Marshal has been completed and that the annual permit remains valid. Document the repairs, tests, and weather readings. If any condition is unresolved, keep the ride closed rather than reopening on schedule.