Patent ID: 7441670

Claim:
A derrick crane having a main boom ( 10 ), an auxiliary boom ( 40 ) connected to a tip of the main boom ( 10 ) at a joint therebetween, said auxiliary boom ( 40 ) having a portion at which a lifting cable is disposed, a derrick boom ( 20 ), a stay cable assembly ( 30 ) to guy the main boom ( 10 ), said stay cable assembly ( 30 ) being attached at a first connection point to the main boom ( 10 ) and at a second connection point to the derrick boom ( 20 ) without boom strut(s) in the stay cable assembly ( 30 ) between said first and second connection points, a first auxiliary stay cable ( 50 ) attached to the auxiliary boom ( 40 ) and extending from the auxiliary boom ( 40 ) to the stay cable assembly ( 30 ) wherein the first auxiliary stay cable ( 50 ) is attached to and terminates at the stay cable assembly ( 30 ) at a connection point of the first auxiliary stay cable ( 50 ) between first and second ends of the stay cable assembly ( 30 ), and an additional auxiliary stay cable ( 60 ) being provided between the connection point of the first auxiliary stay cable ( 50 ) on stay cable assembly ( 30 ) and the main boom ( 10 ).