It is a very simple test that consists literally in hitting the blade with a coin to produce sounds. The objective is to identify internal damages of the blade by recognizing sound changes.

Es el término que he conocido. Se trata de una inspección no destructiva, ya te redondeo que estoy desde mi smartphone

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Note added at 3 hrs (2016-07-08 18:32:57 GMT)
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Toque de moneda:

Para verificar el daño sospechado, use el método que da un toque de una moneda de determinar el tamaño y la forma de cualquier separación de obligación posible entre el corazón de la piel y de panal, la piel y controlar el cuerno, y la obligación de tira de abrasión áreas

Acá puedes leer en inglés y con gráficas qué es y cómo se hace el "coin tap test" en una pala de helicóptero

http://amt.epubxp.com/i/641928-jan-feb-2016/24



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Note added at 3 hrs (2016-07-08 18:54:04 GMT)
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The Coin Tap Test

Best practices include getting factory training and advice, along with making sure you understand overhaul requirements, inspection differences, repair criteria, and repair limits. One of the primary tests is a “coin tap” audible check of the blade body and the blade erosion shield to identify any discontinuities.

For the coin tap, you create a grid on the blade and use a round metal disc to tap the blade, listening for changes in the tone. You look for any de-bonding in the blade body and in the laminates. If you find issues, then you have to evaluate them from a size, depth, and location perspective. In some specific instances, an ultrasonic test may be needed, but that is very limited.
http://www.aviationpros.com/article/12160715/gauge-the-gouge...


Dean Ward is the director of aftermarket parts and service for Hartzell Propeller Inc. Through his 30+ years with Hartzell Propeller, Ward has gained wide ranging experience that uniquely qualifies him to lead the Aftermarket Parts and Service Team. His team is responsible for aftermarket sales and customer service, forecasting, export compliance, shipping and the Hartzell Service Center.

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Note added at 8 hrs (2016-07-08 23:46:10 GMT)
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My pleasure!