National Commission for the
Certification of Crane Operators
Committed to Quality, Integrity, and Fairness in Testing since 1995

CERTIFICATIONS

Mobile Crane Operator

Written Exam - Answers to Sample Questions

Grove (Truck Mount) - Telescopic Boom Crane-Swing Cab (TLL)

Following are the answers to the Grove TLL sample questions.

Sample Item #1

Configuration On Outriggers Fully Extended Extension N/A
Counterweight 7,800-lb. Removable Ext. Off-set / Angle N/A
Main Boom 70-ft. Block 15 Ton, 1 Sheave, 2-parts of line
Main Boom Angle N/A Ball 7.5 Ton, 10-ft. below tip
Radius 50-ft. Rigging 250-lb.
Other Auxiliary Boom Head Main Rope 1-lb./ft.
Other N/A Aux. Rope 1-lb./ft.

Note: For line in use, when wire rope deductions are required, the wire rope length will be measured from the boom tip to the ground.

What is the net capacity lifting off the main over the side?

A.   10,329 lb.
Incorrect. No deduct for excess main rope.

B.   10,422 lb.
Incorrect. No Auxiliary boom head deduction.

C.   10,779 lb.
Incorrect. Used over the rear chart.

D.   10,279 lb.
Correct.

Gross Capacity
11,450
Block
380
Ball
338
Rigging
250
Main Rope
50
Aux Rope
10
Auxiliary Boom Head
143
Total Deducts
1,171
Net Capacity
10,279

Sample Item #2

Configuration On Outriggers Fully Extended Extension Fixed Extension Stowed
Counterweight 7,800-lb. Removable Ext. Off-set / Angle N/A
Main Boom 70-ft. Block 15 Ton, 1 Sheave, 2-parts of line
Main Boom Angle N/A Ball 7.5 Ton, 10-ft. below tip
Radius 49-ft. Rigging 150-lb.
Other Auxiliary Boom Head Main Rope 1-lb./ft.
Other N/A Aux. Rope 1-lb./ft.

Note: For line in use, when wire rope deductions are required, the wire rope length will be measured from the boom tip to the ground.

What is the net capacity when lifting off the main boom over the side?

A.   10,262 lb.
Incorrect. Forgot rigging.

B.   12,312 lb.
Incorrect. Wrong radius at 45 ft.

C.   10,112 lb.
Correct.

Gross Capacity
11,450
Jib
267
Block
380
Ball
338
Rigging
150
Main Rope
50
Aux Rope
10
Auxiliary Boom Head
143
Total Deducts
1,338
Net Capacity
10,112

  
D.   10,162 lb.
Incorrect. No excess main rope deduct.

Sample Item #3

Configuration On Outriggers Fully Extended Extension Fixed Extension Stowed
Counterweight 7,800-lb. Removable Ext. Off-set / Angle N/A
Main Boom 68-ft. Block 15 Ton, 1 Sheave, 2-parts of line
Main Boom Angle N/A Ball 7.5 Ton, 10-ft. below tip
Radius 44-ft. Rigging 125-lb.
Other Auxiliary Boom Head Main Rope 1-lb./ft.
Other N/A Aux. Rope 1-lb./ft.

Note: For line in use, when wire rope deductions are required, the wire rope length will be measured from the boom tip to the ground.

What is the net capacity when lifting off the main boom over the side?

A.   12,061 lb.
Incorrect. Deducted the tele boom extension.

B.   12,017 lb.
Incorrect. Deducted excess rope.

C.   12,087 lb.
Correct.

Gross Capacity
13,350
Jib
267
Block
380
Ball
338
Rigging
125
Aux Rope
10
Auxiliary Boom Head
143
Total Deducts
1,263
Net Capacity
12,087

  
D.   12,337 lb.
Incorrect. Wrong gross at 70 ft.