使用Confountry Resources的超广岛推测设计与制造

超轻型飞机的定义

1. The definition of ultra light aircraft varies from country to country the aviation regulatory body of the country decides the weight of an aircraft to be classifies as ultra light aircraft. However, the civil aviation authority of Pakistan has no such definition for ultra light aircraft. As a result we selected the empty weight of our aircraft closer to that used in India and set it to 800lb.

客观的

2. The aim of the project is to design and fabricate a full scale ultra light aircraft using in-country resources.
接下来的方法
a）市场调查和研究
b) Conceptual Design
c) Aerodynamic evaluation
d）详细设计，CAD建模
e）全规模制作

飞机的组件
1. Wing
2. Fuselage Cabin
3. Fuselage Truss
4. Horizontal Tail
5. Vertical Tail
6. Flaps
7. Control Surfaces (Ailerons, Elevators, Rudder)
8. Engine Mount
9. Wing Mount
10.连接器/关节
11.着陆装备
12.控制系统

机身
机身is responsible for the largest portion of overall drag for most of the airplanes. Thus it should be sized and shaped accordingly for minimum drag. It contributes to various drags:
•摩擦阻力。
• Profile drag.
• Base drag.
• Compressibility drag.
• Induced drag.
为减少摩擦拖累，可以使用两种选择：
• Shape the fuselage so that laminar flow is possible.
• Reduce the length and perimeter as much as possible.

电厂选择
该飞机的电源要求首先从初始设计中发现，即将出现为60 HP。虽然可以获得我们要求的航空发动机，但金融限制阻止了我们购买它们。因此，进行了市场调查，找到了一个适合满足我们需求的合适的汽车发动机。

替代引擎建议：
Despite promises made by engine suppliers an 1800cc VW engine as required was not made available. As a result a survey was done on the internet for alternate powerplants:
•Rotax Engine：二手双化油机Rotax 503发动机，以2万卢比的成本为5卢比。发动机飞过40小时。它提供了47 HP，但同时其重量为85磅，这几乎是VW发动机估计重量的一半。Rotax发动机的螺旋桨规格可直接在互联网上提供。对于驾驶重量的Rotax 503，在700-850 LBS的范围内，螺旋桨规度为：56×32，其中56是直径，32度是间距。

Fuel system
考虑了两种类型的燃料系统：
•重力喂养燃油系统
• Pressure fed fuel system
Gravity-Feed Systems use only the force of gravity to push fuel to the engine fuel-control mechanism. The bottom of the fuel tank must be high enough to provide adequate pressure to the fuel-control component. This type of system is often used in high-wing light aircraft. We have preferred gravity fed system as it is simple, does not need any installation of pump and suits our aircraft configuration i.e. high-wing light aircraft. However, we need to install two valves to ensure fuel supply at all time
Thus, our fuel tank has two valves to counter for every phase of flight. Fuel from these valves merged together before entering into the engine.
燃料系统组件：
• Tanks
• Lines
• Valves
• Fuel Flow-meters
• Filters and Strainers

结论
Full detail design of the aircraft was carried out which would ensure the integrity of the aircraft. Every possible aspect of design was taken care off from the selection of Bolt size to installation of aircraft engine. Due to shortage of time the fabrication could not be completed. However, the most important part of fabrication, aircraft structure, was fully completed. Material for aircraft covering and controls has also been acquired while the propeller has also been fabricated. The entire fabrication process was carried out using the most economical resources and it was proven that an aircraft can be fabricated in Pakistan using local resources and that too at an extremely low cost.
It is suggested that this project be continued. Inshallah by next semester this project would be fully completed and CAE would be able to claim that its students have successfully designed and flown their own aircraft.