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"Pesawat terbang merupakan wahana udara yang dirancang untuk memenuhi kebutuhan manusia akan transportasi yang lebih cepat. Dalam merancang pesawat terbang satu di antara beberapa bidang ilmu penting yang perlu diperhatikan adalah memodelkan dan mengontrol gerakan pesawat terbang yang terdiri dari kinematika, dinamika, dan stabilitas, sehingga pesawat mampu bermanouver sesuai dengan yang diinginkan. Sistem gerak pesawat merupakan sistem MIMO (Multi Input Multi Output), di mana masing-masing input saling mempengaruhi (berinteraksi) sehingga relatif kompleks untuk dianalisa. Oleh karena itu penerapan metode decoupling pada sistem gerak pesawat akan mengurangi (bahkan menghilangkan) pengaruh interaksi tersebut. Data pesawat dalam penelitian tesis ini diambil dari pesawat CHARLIE [2]. Hasil perhitungan menunjukkan bahwa, sebelum adanya pengendali, gerak pesawat mempunyai karakteristik tidak stabil, karena ada nilai eigen yang positif yaitu 3,4 0.0006 0.0512i l = ± . Tetapi gerak pesawat masih dapat dikontrol (controllability) dan dapat diamati (observability) secara lengkap, karena matriks controllability dan matriks observability mempunyai full rank yaitu 4. Kemudian, setelah menggunakan pengendali dengan metoda decoupling gerakan pesawat sangat setabil, karena output w dapat mengikuti set-point setelah sekitar 12 detik, dan output q dapat mengikuti set-point setelah sekitar 14 detik.

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Aircraft is mode air transportation faster movement. For designing model an aircraft need sufficient knowledge field of controls such as kinematic, dynamics and stability to fulfill requirement as needed. Parameters data for calculation and simulation longitudinal motion to be used in this thesis are taken from CHARLIE aircraft [2].

Before using controller, aircraft has unstable characteristics, because it has two positive eigen value i.e. 3,4 0.0006 0.0512i l = ± . Aircraft still both controllable and observable, because has full rank controllability and observability matrix i.e. 4. Design controller in this thesis using decoupling method because this method can be able elimination interaction multi input multi output. After using controller, motion of aircraft is very stable, both output, vertical velocity w and angular speed q match set-point."

"The numerical simulation of heat transfer and pressure drop characteristics was carried out on the airflow through a rectangular channel-mounted vortex generator (VG). The VG was installed on a plate that was attached to the heater. The inlet velocity of the airflow varied from 0.4 to 2.0 m/s. The VGs used in this study were concave delta winglet pairs (CDWPs) with the attack angle of 30° and with variation in the number of rows: one pair, two pairs, and three pairs. The CDWPs are predicted to produce the longitudinal vortex (LV), which increases the intensity of turbulence resulting in better mixing of flow. This, in turn, can improve the heat transfer between the plate surface and the airflow in the rectangular channel. The results showed that the installation of CDWPs does improve the overall heat transfer performance. However, it has the consequences of a greater pressure drop. Based on the variation in the number of rows, the greater the number of pairs of VGs was the greater the convection heat transfer coefficient (h) in both laminar and turbulent flows. The h value was based on the number of row of CDWPs: one pair, two pairs, and three pairs exhibited increases of 65.9-108.4%; 34.4-71%; and 42.2-110.7% compared to the baseline, respectively. A great number of rows of VGs also led to an increasing pressure drop value in laminar and turbulent flows. The percentage increases in pressure drop for CDWPs with one pair, two pairs, and three pairs, as compared to the baseline, were 70.1-92.1%; 123.6-161.3%, and 180-266.9%, respectively."