Request Information’s of the Forged Parts of Airplanes as Gear Land System

I would appreciate to know about problems with failures (broken) in forged parts of airplanes as land gear system due to metallic material defects (steel) and cracks.
The reason I have been asking these information is due to the fact that the aerospace industry is one of the field where happen the largest investigation and researches related with structural defects in metal parts. Any information would be important about historical problems.

My concern has related with parts denominated as front axle beams used in land vehicles (bus and truck), that has been classified as security parts even more critical that bracken system. The front axle beams with defects were supplied at the specific Assembling Truck Company for production lines: France, Brazil and Sweden. Its possible those parts could be with defects related with the material and cracks of the production process, which could decrease the fatigue resistance in its use for bus and trucks.

The problem was detected after 850 parts had been assembled in vehicles in Brazil and approximate 2000 parts in maritime route for Europe. All the parts has had defects of it burns of the steel, that happens when the steel and submitted to high forge temperatures for long periods, and this defect has as main characteristic the loss of carbon of the structure of the metal, decreasing its resistance . Along with that defect were finding out parts with cracks in the proportion of the 20% of the forged parts of this same batch.

After the detection of the defects were takings two actions by the manufacturing company of these parts:
A team of employees was send for the places of storage(warehouses) of the parts in Europe, before Its to arrive the Assembling Company, to inspect the parts with the objective of separating the parts with cracks of the remaining of the batch, but all those parts has had material defect;

It was identified the parts with the largest cracks in the batch, along with defect in the material to submit it’s at the tests of resistance to the fatigue in laboratory of the company, to determine the loss of durability of the parts. After the conclusion of this tests would be analyzed the real need to inform the customer about the production problems;

After two weeks of test in the laboratory, that it was accomplished correctly, the result was a pleasant surprise, even the parts selected for this test had the largest defect level among 1200 inspected, the result demonstrated that the parts had obtained a larger useful life, better than the parts of initial batch (product development) that customer approved according for the rules of ISO-TS. Due to this result the manufacturing company didn’t inform the Assembling Company (customer) about the problem and It had just decided to scrap the parts with cracks in Europe (Sweden and France) and along those were in the production process, while all the parts supplied with material defect for Europe and all the parts with cracks and material defect already in use in vehicles in Brazil would not be replaced.

All these facts had happened between July and July of 2007 and all vehicles (trucks and bus) with those parts has been working since then. The front axle beam rarely breaks or it is replaced. It will remain in operation while the vehicles has been used, in the Brazil case it could mean more than 20 years, accumulating several hundreds of thousands of Km in highways that most case the tracks resemble the lunar surface, what decreases the useful life when compared with highways of good quality. Due this aspect is possible to imagine that the first vehicles with broken front axle beam would happen in Brazil first, but this it’s only a supposition because the vehicles has been assembled in Europe and could be exported for others Continents.

I have had reasons to suspect that the parts had sent to the laboratory for analysis belong at the other production batch that hasn’t defects, and the decisions made were based on an incorrect information resulting of the fatigue tests of the part without defects.

I have been feeling haunted with the possibility of those parts will break and put lives in risk. Because this fact I have ask help of everybody that have information about break of forged parts in airplanes as the landing gear, that has characteristic as the front axle beams. My proposal is gather information’s to send for those companies about my concerning , once till now I haven’t been found the courage of exposing my suspects for the companies involved with it problems due my missing of knowledge .