Rotorcraft Design: The Crucial Influence of Safety from Concept to Fleet Support The 41st Alexander A. Nikolsky Honorary Lecture

It is an immense honor to have been selected to hold the prestigious 41st Nikolsky Lecture and to have the opportunity to synthesize my experiences with regards to the most important principle that permeates aeronautical engineering—“the concept of safety.” Having worked in the rotary-wing field for 39 years, with growing levels of involvement and responsibilities, I have been involved in the design, development, and certification of many helicopter models at the Leonardo Helicopters Division (LHD; formerly Agusta and then AgustaWestland), such as A109, A119, EH101, A129, NH90, AW609. More recently, I had the full responsibility of design, development, certification, and entry into service of three new helicopter types within the “AW Family concept”, specifically the AW139, AW189, and AW169. I am profoundly grateful for the mentors encountered in my professional life—Bruno Lovera and Santino Pancotti, both of whom were also honored with the Nikolsky Lectureship. In working with them, not a single day passed where the word “safety” was not mentioned. They taught me that “safety” shall be the mantra of every aeronautical engineer because it is our principal duty and responsibility, towards those who travel in, work on, and work with our products and entrust their lives to our work and professionalism daily. I have tried hard never to forget this lesson, and to convey this to the young engineers that I have had the chance and pleasure to work with. If I have been able to pass on this lesson successfully, through my work with others through this lectureship, it would be the greatest achievement of my life. In this vein, this paper is organized in three parts: (i) definitions and principles, along with some “philosophical” concepts; (ii) the application of these principles at Leonardo in the design of the latest generation of helicopters, and finally (iii) a discussion of emerging “safety technologies” that promise to improve the safety of future helicopters and operations.

A New Scoring System for use in Capture-Recapture Studies for Bowhead Whales Photographed with Drones

Effective management of animal populations requires knowledge of life history parameters and estimates of population abundance. One method commonly used to estimate abundance is capture/recapture analyses of photographs. Small, relatively inexpensive, rotary-wing drones have become an effective platform for obtaining high-quality aerial photographs of whales. To conduct capture/recapture analyses the animal needs to be defined as marked or unmarked and the photographs must be of high quality. While a system for scoring quality and markedness has previously been developed for bowhead whales (Balaena mysticetus) (Rugh et al. 1998), a revised scoring system was needed to incorporate increased information in photographs taken by drones. We present a revised scoring system that enlarges two of the previously defined areas of the whale examined for markings and incorporates smaller markings into the definition of marked whales. We scored 30 whales using the previous criteria and the revised criteria developed in this paper. More whales were identified as marked (23%) and mark scores were higher for 30% of the zones scored using the new system. Increasing the number of marked whales during capture/recapture studies increases the precision of estimated parameters and permits us to make those estimates with smaller samples of photographs.

Perancangan Sistem Pengendalian Menggunakan Kontroler PID pada Gerakan Pitch dan Roll untuk Stabilitas Attitude Hexacopter

Drone Hexacopter merupakan salah satu jenis UAV tipe rotary wing. Hexacopter memiliki 6 buah motor penggerak, biasa disebut multirotor. Drone Hexacopter memiliki sistem yang kompleks dan nonlinear. Sifat sistem hexacopter menyebabkan proses pengendalian sulit dilakukan saat sistem kontrol tidak dirancang dengan baik sehingga menjadi tantangan untuk penelitian mendatang. Dibutuhkan perancangan sistem kontrol hexacopter yang dapat menjaga kestabilan gerak attitude saat drone berada di udara yaitu variabel pitch dan roll. Tujuan dari penelitian ini ialah menentukan parameter PID untuk gerakan pitch dan roll pada hexacopter. Penelitian ini, pemodelan sistem untuk mendapatkan transfer function dilakukan dengan engineering tools black-box modeling yaitu Autoreggresive Moving Average eXogenous (ARMAX). Metode ini menggunakan data input dan output drone berupa sudut perintah dan sudut aktual (pitch dan roll). Perancangan kontroler dilakukan dengan mencari parameter PID lalu dilakukan simulasi menggunakan software komputer. Hasil setelah perancangan diharapkan mengalami improvisasi atau lebih baik dari sistem sebelumnya setelah dilakukan simulasi.

Coupling Mid-Fidelity Aerodynamics and Multibody Dynamics for the Aeroelastic Analysis of Rotary-Wing Vehicles

A mid-fidelity aerodynamic solver based on the vortex particle method for wake modeling, DUST, is coupled through the partitioned multi-physics coupling library preCICE to a multibody dynamics code, MBDyn, to improve the accuracy of aeroelastic numerical analysis performed on rotary-wing vehicles. In this paper, the coupled tool is firstly validated by solving simple fixed-wing and rotary-wing problems from the open literature. The transient roll maneuver of a complete tiltrotor aircraft is then simulated, to show the capability of the coupled solver to analyze the aeroelasticity of complex rotorcraft configurations. Simulation results show the importance of the accurate representation of rotary wing aerodynamics provided by the vortex particle method for loads evaluation, aeroelastic stability assessment, and analysis of transient maneuvers of aircraft configurations characterized by complex interactional aerodynamics. The limited computational effort required by the mid-fidelity aerodynamic approach represents an effective trade-off in obtaining fast and accurate solutions that can be used for the preliminary design of novel rotary-wing vehicle configurations.