1、Lessons Learned Entry: 0937Lesson Info:a71 Lesson Number: 0937a71 Lesson Date: 2001-01-01a71 Submitting Organization: KSCa71 Submitted by: Malcolm GlennSubject: Mobile Crane Mishap Description of Driving Event: A three-man crane operating crew was assisting a three-man crane overhaul crew to refurbi
2、sh a 140-ton crew and to refurbish a 110-ton government owned mobile crane on September 15, 2000. On this day, the overhaul crew was to install new boom pendants, requiring the cable bridle and its associated cables to be moved from its temporary stowage location behind the cab of the crane to a poi
3、nt on the boom where it could be attached to the boom pendants. To move the bridle with its associated cables forward along the length of the boom, a second 65-ton government owned mobile crane was used to lift the cable bridle assembly and pull it to the new location. The cable bridle (weighing app
4、roximately 1100 pounds) was attached to the hook of the 65-ton crane with a web sling (rated for 10,000 pound capacity in the vertical choker configuration) used in a horizontal choker configuration.The crane operating personnel were performing the following duties: One member operated the 65-ton cr
5、ane used to lift the cable bridle assembly and pull it to its new location. A second member operated the 140-ton crane in order to play out cable while the bridle assembly was being pulled. The third member was on the ground acting as the signalman for the two crane operators. With the three crane o
6、perating crew members in position and the overhaul crew members observing the operations, the cable bridle was lifted and slowly pulled along the boom of the 140-ton crane. During this movement the cable bridle underwent several yawing motions due to the cables binding on the sheaves as the cable un
7、spooled from the take-up drums. The sheaves were binding because the cables were being pulled at an angle and the choker hitch configuration did not keep the bridle straight and level with the direction of pull.The web sling failed allowing the bridle to fall. The bridle assembly impacted the butt s
8、ection of the boom of the 140-ton crane before it landed on the ground. At the same time, the block of the 65-ton crane swung back striking the stowed jib boom attached to the main boom of the 65-ton crane. The Provided by IHSNot for ResaleNo reproduction or networking permitted without license from
9、 IHS-,-,-jib boom of the 65-ton crane was a total loss because a portion of the main support section was severely damaged beyond repair. The butt section of the boom of the 140-ton crane was slightly bent and the bridle was damaged in several places. The falling cables cracked the overhead glass on
10、the cab of the 140-ton crane.Lesson(s) Learned: a71 Follow all procedures/instructions for handling and operation of materials and equipment. Ensure edge protection devices are used.a71 A single person is to be designated as the person in charge for all crane and hoist operations; as such, shall con
11、duct a pre-task briefing, establish a safety zone, ensure all equipment is in safe working order and the load properly rigged, prior to commencing operations.a71 Ensure written procedures are available and used for all crane and hoist operations involving complex configurations and/or requirements.
12、Prior to use, the written procedures shall have been reviewed and approved by appropriate levels of Management, Engineering, Safety and Health, and Quality.a71 Prohibit the use of cranes and hoists for pulling, dragging or any operations that would cause side loading unless the crane or hoist is spe
13、cifically designed to do so.Recommendation(s): Follow all procedures/instructions for handling and operations of materials and equipment. Ensure edge protection devices are used.Evidence of Recurrence Control Effectiveness: N/ADocuments Related to Lesson: N/AMission Directorate(s): a71 Exploration S
14、ystemsa71 Space Operationsa71 Aeronautics ResearchAdditional Key Phrase(s): a71 Ground OperationsProvided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-a71 Lifting Devicesa71 Packaging Handling Storagea71 Safety & Mission AssuranceAdditional Info: Approval Info: a71 Approval Date: 2001-05-17a71 Approval Name: Eric Raynora71 Approval Organization: QSa71 Approval Phone Number: 202-358-4738Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-
