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Show K:Mei Safer A new inspection technique Employed by the Ogden Air logistics Center is added in-.jiance in-.jiance for a pilot making a Jit turn in a modified F-4E tiantom jet. HE KNOWS that the 1,200 'nit holes that fasten the slats si the wings of his craft have been scientifically inspected ml found A.O.K. Tie inspection technique, j unfiled by the Physical Sciwvcfe laboratory at Ogden ALC is known as Non-Des-luctive Inspection (NDI). NDI IS used extensively throughout the Air Force logistics Command. X-ray eddy current, ultrasonic sound, magnetic particles and other techniques are ised. A project to install slats on wings of F-4Es has been underway un-derway at Ogden ALC since June 1973. THE SLATS look like spoilers on sports cars. They are attached to the forward part of each wing and make a decided difference in the F-4E's F-4E's turning capability. To install a slat kit on each F-4 requires drilling 1,200 bolt holes in the wings. EACH BOLT hole needs a " personal inspection to insure that it is free from critical defects. Stress, corrosion or fatigue cracks around the holes could cause wing failure and loss of a plane and crew. The previous inspection method done manually, required 100 manhours per aircraft. AN INSPECTOR had to stand under the wing, extend his arms upward, insert the probe, turn it manually and watch a dial for fluctuations from norm. He then had to stop the machine, locate the position, length and direction of any crack and record the data. By the end of the workshift, the employee was exhausted. A new NDI technique changed that. THE PHYSICAL Science' Laboratory, headed by Dr. Charles Bock, gave the ' problem of tedious inspection of the F-4E bolt holes a top priority. A commerical concern had developed a prototype of an automatic eddy current scanner and the firm was interested in various industrial indus-trial applications. THE LAB and the contractor, contrac-tor, working together, developed an automatic eddy current scanner for use in the bolt holes. The new system uses a hand-held unit which rotates a probe within the hole. The condition of the hole's interior is recorded on both an os-cilliscope os-cilliscope screen and strip-chart strip-chart recorder. The recording device provides a readout that can be stored for future reference. DR. BOCK said that the unit provides a continuous scan of the fastener holes and is extremely accurate in locating defects. The unit weighs about four pounds. The periscope-type probe can turn up to 100 rpm. UTILIZING THE device has become a real cost saver. It takes about 50 manhours to do an inspection of an F-4E --half --half the time it did previously. Dr. Bock said that the Ogden Og-den ALC NDI technique is being adapted for Air Force-wide Force-wide use on such aircraft as theC-5, C-141 and F-lll. |