The Art of Measurement


Whether intensive use or natural wear and tear, each tool undergoes alterations that can cause its malfunction. This problem is all the more true when it comes to measuring instruments that may be subject to disturbances invisible to the naked eye.

In order to ensure optimum accuracy, which is essential for the reliability and traceability of the proposed results, each instrument must be audited or calibrated - according to the desired level of compliance -.

Together, let's take a look at these two recognized but often confused metrological practices...

AIR SUPPORT - Aircraft component MRO - Verification vs calibration

According to the metrological definition of the term, VERIFICATION, is the provision of objective evidence that a given item fulfils specified requirements, taking any measurement uncertainty into consideration.*

It ensures that deviations between the values indicated by a measuring device and the corresponding known values of a measured quantity are all lower than the maximum permissible errors (MPE).

AIR SUPPORT - Aircraft component MRO - Verification

Unlike the calibration that will provide encrypted data, the verification provides a binary response: compliant / non-compliant. This sanction is recorded in the verification report.

, for its part, is an operation that, under specified conditions:

> In a first step establishes a relation between the quantity values with measurement uncertainties provided by measurement standards and corresponding indications with associated measurement uncertainties

> In a second step, uses this information to establish a relation for obtaining a measurement result from an indication*

AIR SUPPORT - Aircraft component MRO - Verification

A calibration may be expressed by a statement, calibration function, calibration diagram, calibration curve or calibration table.

In order to meet quality requirements, verificatons and calibrations must be carried out at establishments accredited by the French Accreditation Committee (COFRAC). This acronym brings the guarantee of an expertise on the subject and ensures that each instrument will be analyzed by the book.

* Definition of the International Bureau of Weights and Measures

AIR SUPPORT - Aircraft component MRO - Best practices

AIR SUPPORT, a certified Part 145 MRO actor, has 25 years of expertise and an exemplary customer satisfaction rate. In order to maintain this level of excellence, the quality of our tooling is a key element, which is why we have put in place a rigorous monitoring of each tool used in our workshops.
In addition to the responsibility assigned to each of our technicians when using a tool for repairing a part, AIR SUPPORT's Quality Department ensures that regular maintenance is guaranteed from the purchase to the end life of all tools.

AIR SUPPORT - Aircraft component MRO - CVI Responsable Etalonnage

Christophe VIGNAL, Production Assistant, is in charge of the management of the measuring instrument fleet for AIR SUPPORT. Dealing with a set of more than 600 measuring instruments distributed in our various workshops, he can rely for this mission of an automated system allowing to follow each piece individually.
The two metrology processes are underway in our organization, although the verification is more regularly acclaimed.

With regard to the calibration acts, three different solutions are used:

> Internally. Christophe carries out these exercises thanks to our own measurement standards - themselves certified by authorized service providers -.

> At the contractor's site. AIR SUPPORT uses a selection of qualified service providers (regular audits) to calibrate our instruments in their workshops

> By the provider, in our workshops. In some cases, it is impossible to send our tools outside because this would result in immobilization of our test machine over too long, so we call on a service provider who will intervene directly on site.

Our increased vigilance on these metrology issues allows us to meet the requirements of the Part 145 certification but also meet the criteria of the EN9110 certification which sanctions the quality of our services.

For more information, contact us!

AIR SUPPORT - Aircraft component MRO - Pried à coulisse