Navigation path

Decrease textIncrease textDividerPrint versionRSSDivider

Improved ReliabIlity Inspection of Aeronautic Structure through Simulation Supported POD

Tags: Air

State of the Art - Background

With ageing engines and the expected increase of air traffic in the next 20 years, a central challenge in the aeronautical industry will concern the increase of efficiency in maintenance which still represents around 20% of an operator's indirect operating costs. This challenge is particularly important for metallic parts within the engine and aircraft industry. Maintenance is directly related to the concept of Probability of Detection (POD) curves which are obtained by expensive experimental campaigns.

Furthermore, the aeronautics regulations and expectations regarding safety are really increasing, imposing enhanced expectations on Probability of Detection (POD) sizing. In particular, new aeronautic regulations require appropriate damage tolerance assessments for critical parts (for example compressor and turbine disc), to address the potential for failure from material, manufacturing and service induced anomalies within the Approved Life of the part.

Within the PICASSO project, we propose to evaluate the concept of using Non Destructive Testing (NDT) low cost simulations to obtain POD curves.


The aim of PICASSO is to build a new and original concept of "simulation supported POD curves-based on NDT simulation in addition to existing experimental data base".

The main objectives of the PICASSO project are to increase the accuracy, and reduce the cost of, a Probability of Detection campaign with Non-Destructive Testing simulation techniques.

This will be achieved by:

- Completing experimental NDT inspections by simulated NDT inspections - suppressing the needs of manufacturing expensive samples with defects;

- More representative samples of the population for the POD campaign - enhancing the accuracy of the POD samples and increasing their numbers thanks to simulation techniques;

- Delta POD approach - suppressing the need of a new POD campaign for similar parts or inspection configurations.

The main impacts of the project will be:

- To improve the answer to FAA/EASA damage tolerance requirements with higher knowledge and accuracy on NDT inspection PODs;

- Savings in costs concerning aircraft maintenance and engine development.

Description of Work

The project is divided into four technical Work Packages (WPs).

WP1 aims to procure the initial inputs of the project (material properties, defect description, data from equipment) and the validation cases to be used as experimental data for the comparison, with model-based POD calculations.

WP2 gathers the tasks concerning the modelling. NDT simulation software have to take into account the complexity of real situations: the complexity of parts, materials and defects, and the fluctuations coming from a large number of influential parameters.

In this WP2, the models will be highly improved by developers to achieve accurate and numerically efficient simulation tools, and to be reliable enough for intensive use for POD calculations.

WP3 focuses on POD issues and deals with the introduction of simulated data in POD studies. The objective of WP3 is to develop a simulation supported POD methodology. Common methodologies and tools for low cost POD determination using a simulation supported strategy will be developped. Major expected results is the development of a prototype POD software platform.

WP4 is concerned with the assessement and validation of the new simulation supported POD methodology developed in WP3. It will be performed by the comparison between experimental and simulation of POD data.

Expected Results

The main result of the project will be the validation of the concept of 'simulation supported POD' by first realistic results, implementation and methodologies.

Through realistic industrial applications, design offices and maintenance departments will have at the end of the project a clear overview of the potential impacts.

Methodology recommendations obtained as a result of the project on simulation supported POD determination will enable to establish the basis and recommendations for a future European standard for qualification and reliability of inspection for the aircraft industry.

In this context, Aircraft European industry will increase its competitiveness and the aircraft safety level.

Its intensive use and the building of a future EU standard on simulation supported POD will be the next step towards the entry into service of such tools.

Example of POD curve
Example of POD curve