NCCCO Service Truck Crane Questions and Answers
with Rationale Latest Edition 2026/2027
Section 1: General Technical Information & Wire Rope
Question 1
What is the primary operational consequence when the number
of layers of wire rope wound on a hoist drum increases?
A. Allowable line pull increases proportionally.
B. Allowable line pull decreases.
C. Breaking strength of the rope increases automatically.
D. Drum torque capacity is enhanced.
Correct Answer:
B
Rationale:
As successive layers of wire rope wind onto a hoist drum, the
effective drum diameter increases, which leverages a mechanical
disadvantage against the winch motor/gearbox, thereby
decreasing the allowable line pull rating for upper layers.
Question 2
According to standard safety requirements for running wire
ropes, how many randomly distributed broken wires in a single
,lay must be present to warrant removing the wire rope from
service?
A. 2 broken wires
B. 4 broken wires
C. 6 broken wires
D. 12 broken wires
Correct Answer:
C
Rationale:
ASME B30.5 and OSHA guidelines dictate that running wire
ropes must be removed from service if there are 6 randomly
distributed broken wires in one rope lay, or 3 broken wires in
one strand of one lay.
Question 3
When installing new wire rope from a storage reel onto a crane’s
hoist drum, what is the preferred method to prevent twisting and
birdcaging?
A. Top-of-reel to top-of-drum, or bottom-of-reel to bottom-
of-drum (matching manufacturer flow).
B. Top-of-reel to bottom-of-drum.
C. Random cross-winding under heavy load.
, D. Spooling manually across open air without tension.
Correct Answer:
A
Rationale:
To maintain proper internal stress layout and prevent the
introduction of reverse bends or twist memory into the wire
rope, matching the spooling direction (top-to-top or bottom-to-
bottom) from reel to drum is standard practice.
Section 2: Setup & Site Safety
Question 4
When setting up a service truck crane equipped with
outriggers/stabilizers on soft or questionable ground, what is the
most effective initial step to distribute the machine's load safely?
A. Retract outriggers halfway to lower the center of gravity.
B. Use adequately sized outrigger pads, wood blocking, or
timber cribbing under the pads.
C. Rely solely on the factory-welded float pads regardless of
soil conditions.
D. Lower the truck tires completely off the ground without
mats.
Correct Answer:
B
, Rationale:
Spreading the load over a larger surface area using solid timber
mats or outrigger pads reduces ground bearing pressure,
preventing sinkage or structural tipping incidents.
Question 5
Within what maximum percentage of level must a telescopic
boom service crane be maintained for its load chart ratings to
remain valid?
A. Within 1% to 1.5% level (or strictly following the
manufacturer’s specification).
B. Within 5% level.
C. Within 10% level.
D. Leveling accuracy does not affect telescopic chart
parameters.
Correct Answer:
A
Rationale:
Cranes rely heavily on a level chassis to prevent side-loading
components and shifting centers of gravity. Most manufacturers
specify precise leveling criteria (frequently within 1% slope) via
integrated bubble levels.
Question 6
with Rationale Latest Edition 2026/2027
Section 1: General Technical Information & Wire Rope
Question 1
What is the primary operational consequence when the number
of layers of wire rope wound on a hoist drum increases?
A. Allowable line pull increases proportionally.
B. Allowable line pull decreases.
C. Breaking strength of the rope increases automatically.
D. Drum torque capacity is enhanced.
Correct Answer:
B
Rationale:
As successive layers of wire rope wind onto a hoist drum, the
effective drum diameter increases, which leverages a mechanical
disadvantage against the winch motor/gearbox, thereby
decreasing the allowable line pull rating for upper layers.
Question 2
According to standard safety requirements for running wire
ropes, how many randomly distributed broken wires in a single
,lay must be present to warrant removing the wire rope from
service?
A. 2 broken wires
B. 4 broken wires
C. 6 broken wires
D. 12 broken wires
Correct Answer:
C
Rationale:
ASME B30.5 and OSHA guidelines dictate that running wire
ropes must be removed from service if there are 6 randomly
distributed broken wires in one rope lay, or 3 broken wires in
one strand of one lay.
Question 3
When installing new wire rope from a storage reel onto a crane’s
hoist drum, what is the preferred method to prevent twisting and
birdcaging?
A. Top-of-reel to top-of-drum, or bottom-of-reel to bottom-
of-drum (matching manufacturer flow).
B. Top-of-reel to bottom-of-drum.
C. Random cross-winding under heavy load.
, D. Spooling manually across open air without tension.
Correct Answer:
A
Rationale:
To maintain proper internal stress layout and prevent the
introduction of reverse bends or twist memory into the wire
rope, matching the spooling direction (top-to-top or bottom-to-
bottom) from reel to drum is standard practice.
Section 2: Setup & Site Safety
Question 4
When setting up a service truck crane equipped with
outriggers/stabilizers on soft or questionable ground, what is the
most effective initial step to distribute the machine's load safely?
A. Retract outriggers halfway to lower the center of gravity.
B. Use adequately sized outrigger pads, wood blocking, or
timber cribbing under the pads.
C. Rely solely on the factory-welded float pads regardless of
soil conditions.
D. Lower the truck tires completely off the ground without
mats.
Correct Answer:
B
, Rationale:
Spreading the load over a larger surface area using solid timber
mats or outrigger pads reduces ground bearing pressure,
preventing sinkage or structural tipping incidents.
Question 5
Within what maximum percentage of level must a telescopic
boom service crane be maintained for its load chart ratings to
remain valid?
A. Within 1% to 1.5% level (or strictly following the
manufacturer’s specification).
B. Within 5% level.
C. Within 10% level.
D. Leveling accuracy does not affect telescopic chart
parameters.
Correct Answer:
A
Rationale:
Cranes rely heavily on a level chassis to prevent side-loading
components and shifting centers of gravity. Most manufacturers
specify precise leveling criteria (frequently within 1% slope) via
integrated bubble levels.
Question 6
