Issue 78

C. Vendittozzi et alii, Fracture and Structural Integrity, 78 (2026) 519-540; DOI: 10.3221/IGF-ESIS.78.30

Field FBG monitoring of helicopter landing gear: data integrity screening and time–frequency characterization of operational events

Cristian Vendittozzi Sapienza University of Rome, Italy

cristian.vendittozzi@uniroma1.it, https://orcid.org/0000-0003-0793-4052 Angela Brindisi, Antonio Concilio, Salvatore Ameduri CIRA (Centro Italiano Ricerche Aerospaziali, Italian Aerospace Research Centre), Italy

a.brindisi@cira.it, http://orcid.org/0000-0002-8526-3015 a.concilio@cira.it, http://orcid.org/0000-0001-8150-147X s.ameduri@cira.it, http://orcid.org/0000-0001-6238-3594 Emilia di Micco, Filippo Berto, Stefano Natali Sapienza University of Rome, Italy

emilia.dimicco@uniroma1.it, https://orcid.org/0009-0007-3166-0334 filippo.berto@uniroma1.it, http://orcid.org/0000-0001-9676-9970 stefano.natali@uniroma1.it, https://orcid.org/0000-0002-2742-0270 Daniele Tittoni CNVVF (Corpo nazionale dei Vigili del Fuoco, Italian National Firefighter Corps), Italy daniele.tittoni@vigilfuoco.it

Citation: Vendittozzi, C., Brindisi, A., Concilio, A., Ameduri, S., di Micco, E., Berto, F., Natali, S., Tittoni, D., Field FBG monitoring of helicopter landing gear: data integrity screening and time–frequency characterization of operational events, Fracture and Structural Integrity, 78 (2026) 519-540.

A BSTRACT . Operational monitoring of helicopter landing gear can benefit from direct strain measurements able to resolve transient contact and roll-out dynamics. This work presents a field demonstration of a fiber Bragg grating (FBG) measurement and processing workflow applied to the main landing gear of an Erickson S-64 Skycrane operated by the Italian National Fire Brigade. Four gratings were bonded to the landing-gear structure, and wavelength data were acquired at 1 kHz during operational activities. The study does not aim to perform damage detection, health-state assessment, or hard-landing classification; rather, it evaluates whether field-acquired FBG signals affected by realistic acquisition imperfections can be transformed into interpretable time–frequency descriptors. Raw wavelength records were

Received: 18.06.2026 Accepted: 16.09.2026 Published: 24.09.2026 Issue: 10.2026

Copyright: © 2026 This is an open access article under the terms of the CC-BY 4.0, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.

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