1
NCCCO Mobile Crane Exam
(2025/2026) Questions and
100% Correct Verified
Answers | Grade A
1. When using a mobile crane load chart, what does the term "on-
rubber" lifting condition refer to? A. Lifting with outriggers fully
extended B. Lifting with tires on the ground and outriggers partially
retracted C. Lifting solely on outriggers without tire support D. Lifting
in high wind conditions
B Rationale: "On-rubber" indicates the crane is lifting with its tires
bearing weight, typically with outriggers partially or fully retracted,
reducing capacity due to instability compared to full outrigger
deployment. This is critical for site-specific load planning per ASME
B30.5.
2. In a telescopic boom crane load chart, how is the gross load
calculated if the actual load is 15 tons and rigging weight is 2 tons?
A. 15 tons minus 2 tons B. 15 tons plus 2 tons C. 15 tons divided by 2
tons D. 15 tons times 2 tons
B Rationale: Gross load includes the actual load plus all rigging,
attachments, and auxiliary equipment weights to ensure the total does
not exceed chart capacities, preventing overload per NCCCO core
examination standards.
3. What adjustment must be made to a load chart radius when the
crane is operating on a side slope of 3 degrees? A. Increase radius by
, 2
10% B. Use the chart as is, no adjustment C. Increase effective radius by
the cosine of the slope angle D. Decrease radius by 5%
C Rationale: Side slopes increase the effective load radius; the
adjustment uses the cosine of the slope angle (cos 3° ≈ 0.999, but
precisely calculated) to derate capacity, as required by ASME B30.5 for
accurate load moment calculations.
4. For a lattice boom crane, if the load chart specifies a capacity of
20 tons at 30 feet radius with 100 feet of boom, what happens to
capacity if boom length increases to 120 feet? A. Capacity increases
proportionally B. Capacity remains the same C. Capacity decreases due
to increased moment arm D. Capacity is recalculated based on jib length
only
C Rationale: Longer boom lengths increase the structural stress and
tipping moment, reducing allowable load at the same radius, as load
charts are interpolated for boom/jib combinations to maintain stability
margins.
5. When deducting for auxiliary hoist line, how many wraps are
typically considered in the load chart deduction? A. 5 wraps B. 10
wraps C. All wraps on the drum D. Only the working wraps
B Rationale: Standard deduction assumes 10 wraps of wire rope on the
drum for auxiliary lines, accounting for weight in gross load calculations
to avoid underestimating total suspended weight per manufacturer
guidelines.
6. In a load chart with multiple configurations, which factor
primarily determines the selection of the "A" or "B" chart? A.
Boom angle B. Counterweight configuration C. Wind speed D. Ground
bearing pressure
NCCCO Mobile Crane Exam
(2025/2026) Questions and
100% Correct Verified
Answers | Grade A
1. When using a mobile crane load chart, what does the term "on-
rubber" lifting condition refer to? A. Lifting with outriggers fully
extended B. Lifting with tires on the ground and outriggers partially
retracted C. Lifting solely on outriggers without tire support D. Lifting
in high wind conditions
B Rationale: "On-rubber" indicates the crane is lifting with its tires
bearing weight, typically with outriggers partially or fully retracted,
reducing capacity due to instability compared to full outrigger
deployment. This is critical for site-specific load planning per ASME
B30.5.
2. In a telescopic boom crane load chart, how is the gross load
calculated if the actual load is 15 tons and rigging weight is 2 tons?
A. 15 tons minus 2 tons B. 15 tons plus 2 tons C. 15 tons divided by 2
tons D. 15 tons times 2 tons
B Rationale: Gross load includes the actual load plus all rigging,
attachments, and auxiliary equipment weights to ensure the total does
not exceed chart capacities, preventing overload per NCCCO core
examination standards.
3. What adjustment must be made to a load chart radius when the
crane is operating on a side slope of 3 degrees? A. Increase radius by
, 2
10% B. Use the chart as is, no adjustment C. Increase effective radius by
the cosine of the slope angle D. Decrease radius by 5%
C Rationale: Side slopes increase the effective load radius; the
adjustment uses the cosine of the slope angle (cos 3° ≈ 0.999, but
precisely calculated) to derate capacity, as required by ASME B30.5 for
accurate load moment calculations.
4. For a lattice boom crane, if the load chart specifies a capacity of
20 tons at 30 feet radius with 100 feet of boom, what happens to
capacity if boom length increases to 120 feet? A. Capacity increases
proportionally B. Capacity remains the same C. Capacity decreases due
to increased moment arm D. Capacity is recalculated based on jib length
only
C Rationale: Longer boom lengths increase the structural stress and
tipping moment, reducing allowable load at the same radius, as load
charts are interpolated for boom/jib combinations to maintain stability
margins.
5. When deducting for auxiliary hoist line, how many wraps are
typically considered in the load chart deduction? A. 5 wraps B. 10
wraps C. All wraps on the drum D. Only the working wraps
B Rationale: Standard deduction assumes 10 wraps of wire rope on the
drum for auxiliary lines, accounting for weight in gross load calculations
to avoid underestimating total suspended weight per manufacturer
guidelines.
6. In a load chart with multiple configurations, which factor
primarily determines the selection of the "A" or "B" chart? A.
Boom angle B. Counterweight configuration C. Wind speed D. Ground
bearing pressure
