ANALISIS PERBEDAAN KECEPATAN PERAHU DENGAN PENAMBAHAN MESIN INBOARD DAN MESIN OUTBOARD PADA PERAHU SOPEK DI PERAIRAN TAMBAK LOROK SEMARANG - Rosyida, Irma Nur; Pramonowibowo, -; Sardiyatmo, - (Fakultas Perikanan dan Ilmu Kelautan, Universitas Diponegoro, 2015)
Kecepatan merupakan jarak yang ditempuh dalam kurun waktu tertentu, begitu juga dengan kecepatan perahu. Beberapa perahu terdapat tiga mesin yaitu satu mesin utama (mesin inboard) dan dua mesin tambahan (mesin inboard dan mesin outboard). Penelitian ini bertujuan untuk mengetahui perbedaan kecepatan perahu pada penambahan mesin inboard dan mesin outboard berdasarkan pengukuran rpm, kecepatan angin dan konsumsi bahan bakar. Metode penelitian yang digunakan adalah metode eksperimental dan metode deskriptif. Metode eksperimental yang dilakukan yaitu uji coba perbedaan kecepatan perahu berdasarkan penambahan mesin inboard maupun outboard guna memperoleh data primer, sedangkan metode deskriptif yang digunakan yaitu mendeskripsikan hasil uji coba. Analisis data diolah menggunakan Ms. Excel dengan uji Z dan regresi. Hasil analisa data menunjukkan bahwa penambahan mesin inboard dan mesin outboard berpengaruh terhadap kecepatan perahu. Hubungan dan pengaruh rpm terhadap kecepatan perahu yaitu saat putaran rpm rendah, transmisi rendah, momen torsinya tinggi sehingga tenaganya lebih kuat karena tidak mengusahakan gigi transisi, suara mesin kasar dan laju perahu lambat. Saat gas besar pada posisi gigi tinggi, putaran lebih tinggi tetapi momen torsinya rendah sehingga laju perahu cepat dan suara mesin lebih lembut. Hasil kecepatan pada penambahan mesin inboard sebesar 11,84 knot, pada penambahan mesin outboard sebesar 12,49 knot dan penambahan mesin outboard sekaligus inboard yang paling cepat yaitu 12,75 knot. Prosentase efisiensi konsumsi bahan bakar terhadap waktu tempuh 30 menit yang paling efisien sebesar 79,30% pada penambahan mesin inboard. Hal ini berarti bahwa pada penambahan mesin inboard paling hemat dibandingkan dengan penambahan mesin outboard dan penambahan mesin outboard sekaligus inboard.Â The speed is distance in a certain period of time, as well as the speed of boat. There are three engines on several boat, the one engine is main engine (inboard engines) and the two engines are the additional engine (inboard engine and outboard engine). This study aims to determine the differences in the speed of the boat on the addition of inboard engine and outboard engine based on the measurement of rpm, wind speed and fuel consumption. This study method used is experimental method and descriptive method. Experimental method were conducted to test the differences in the speed of the based on the addition of the engine inboard and engine outboard to get the primary data, while descriptive methods used describing the test results. Analysis of the data is processed using Ms. Excel with the test Z and regression. The results of the data analysis showed that the addition of inboard engine and outboard engine affected the speed of the boat. Relation and influence of the rpm of the boat's speed during low rpm rotation, low transmission, high moment torsi so the energy is stronger because it does not animate the transition gear, rough engine noise and the rate of the slow boat. When the gas on high gear position higher rounds but moments torsi low so the pace fast boat and engine noise is softer. The result from additional comparison inboard engine was 11,84 knot. And the additional comparison outboard engines result was 12,49 knot. While the additional adding of outboard engine as well as inboard creates the fastest speeds, the speed reached 12,75 knots. The percentages of the fuel efficiency from 30 minutes travel are the most efficient by 79,30%, on the addition of inboard engines. That means that the addition of inboard engines is the most economical compare with the addition of outboard engines and additions as well combination inboard outboard engine.