NCCCO Tower Crane Operator Test 1 4 — Questions and Answers
Question 1: On a luffing jib tower crane, how is the working radius changed?
- By moving a trolley along a horizontal jib
- By raising or lowering the angle of the entire jib (Correct answer)
- By extending telescoping boom sections
- By repositioning the counterweight along the counter-jib
Correct answer: By raising or lowering the angle of the entire jib
A luffing jib changes radius by varying the jib's angle of inclination rather than moving a trolley.
Question 2: When climbing a tower crane using an internal climbing frame, what must be verified before beginning the climb?
- The jib must be fully retracted and parallel to the mast
- The crane must be in travel mode with all brakes released
- The slewing ring must be locked, load removed, and climbing frame properly seated (Correct answer)
- The counterweight must be removed to reduce mast stress during climbing
Correct answer: The slewing ring must be locked, load removed, and climbing frame properly seated
Before internal climbing, the slewing must be locked, the hook must be empty, and the climbing frame must be properly engaged to safely insert a new mast section.
Question 3: What is the function of the counter-jib on a top-slewing tower crane?
- It provides a walkway for maintenance personnel to access the hoist drum
- It carries the counterweight and hoist machinery to balance the load jib (Correct answer)
- It houses the electrical panel and control systems for the crane
- It acts as a braking surface for the slewing drive during emergency stops
Correct answer: It carries the counterweight and hoist machinery to balance the load jib
The counter-jib extends opposite the load jib and carries counterweights plus the hoist motor to balance the crane.
Question 4: According to OSHA 1926.1416, how often must a tower crane's wire rope be inspected?
- Monthly by the crane owner's insurance carrier
- Annually during the crane's major overhaul
- Before each shift by the operator and periodically by a qualified person (Correct answer)
- Every 500 operating hours by a third-party inspector
Correct answer: Before each shift by the operator and periodically by a qualified person
OSHA requires a visual inspection by the operator before each shift and periodic inspections by a qualified person based on service conditions.
Question 5: A tower crane is equipped with a 'dead man' control. What does this mean?
- Controls automatically return to neutral when the operator releases them (Correct answer)
- The crane shuts down completely if the operator leaves the cab
- Emergency brakes activate if load line tension drops to zero
- The crane cannot be operated without a second qualified person present
Correct answer: Controls automatically return to neutral when the operator releases them
Dead man controls require continuous operator pressure; releasing them causes all motions to stop and brakes to engage.
Question 6: What information is found on a tower crane's load chart that is NOT found on a mobile crane load chart?
- Maximum line pull and drum capacity
- Capacities at various radii for the specific jib length and configuration
- Tip height and hook height clearances
- Specific mast height configurations affecting maximum tip capacity (Correct answer)
Correct answer: Specific mast height configurations affecting maximum tip capacity
Tower crane load charts often include capacity reductions tied to specific mast heights because taller free-standing configurations affect structural ratings.
Question 7: During tower crane operations, a signal person gives a circular motion of the finger pointed upward. What does this signal mean?
- Hoist the load (Correct answer)
- Swing the boom
- Travel in a circle
- Raise the boom
Correct answer: Hoist the load
A circular upward finger motion is the standard ASME B30.3 signal for 'hoist' — raise the load.
NCCCO Tower Crane Operator Test 1 4
On a luffing jib tower crane, how is the working radius changed?