Aerospace 730: Aerospace Systems Study Notes

Definition of Aircraft: According to Section 2 of the New Zealand Civil Aviation Act, 1990, an aircraft is defined as: "any machine that can derive support in the atmosphere from the reactions of the air otherwise than by the reactions of the air against the surface of the earth."
An aircraft functions as a part of a larger aviation system which includes: - The atmosphere - Other aircraft - Aviation operations

Historical references to the evolution of flight and designs: - Leonardo da Vinci's flying machines (illustrated designs) - The significant advancements that have marked the timeline of aerospace engineering.

Overview: Current aircraft operate as part of complex systems that integrate various components and technologies.
The State of Modern Aviation: - Numerous commercial aviation routes and global connectivity. - Comprehensive data on global air traffic, highlighting 10,000 airports and over 67,663 connected air routes.
Economic Impact of Aviation (2019 Pre-COVID): - Passenger Statistics: 4.5 billion trips taken globally. - Employment: Approximately 87.8 million jobs in aviation and related tourism sectors. - Economic Contribution: Aviation contributes significantly to the global economy, with figures showing a mean contribution 4.3 times greater than other job sectors. - Capital Investment: $1 trillion invested in aircraft over a decade (2009-2019). - Civil aviation constitutes approximately 61% of the overall aerospace industry.
Key Categories of Economic Activity in Aviation: - Manufacturing of aircraft, engines, and parts - Operations of airlines and airports - Manufacturing of avionics (aircraft electronics) - Research and development in aviation technologies - Air freight and courier services - General aviation operations

Estimations indicate: - Approximately 2.19 million people employed in the defense sector, with 600,000 directly in aeronautics/aircraft manufacturing. - $909 billion generated in revenue with $148 billion in exports; average compensation: $102,900 (1.4% of the workforce). - Noted USA defense expenditure for 2020 estimated at $1.9 trillion.

Projected figures for 2024 predict 12.7 million international air passengers.
Responsibilities encompass: - Large Flight Information Regions (FIRs) - Search and Rescue (SAR) - Emergency relief operations - Aviation Manufacturing and Maintenance - Training missions, restoration, and autonomous systems development

Various Australia’s Air Operator Certificates (AOC) subdivided into categories, including: - Unmanned Aircraft Operator Certificates - Regulated Air Cargo Operations - Adventure Aviation - Foreign and General Aviation operational permits
Each category entails different operational regulations and certifications within New Zealand Airspace.

Task: Create a System Design for maritime awareness across the South Pacific, considering limitations in RNZAF's capabilities and exploring civilian operational options.

Forces in Flight: Fundamental forces include Lift, Drag, Weight, Thrust, and Buoyancy.
Aircraft characterized by six degrees of freedom: Three translational axes and three rotational axes.

Overall equilibrium necessitates: - All forces summing to zero. - All moments also equating to zero.
Weight must be countered by lift developed through aerodynamic forces.

Characteristics: Use lift for flight; require relative motion to generate lift, composed of fixed-wing, rotary-wing, and ornithopter designs.
Lift is generated against weight, involving drag countered by thrust for effective flight.

Lift is the force counteracting the weight, with coefficients relating to angle of attack (AoA) and aerodynamic efficiency.
Drag arises from the resistance against motion, influenced by lift generation and includes both induced and parasitic components (skin friction, form, and interference).
The minimum drag speed can be calculated using the appropriate drag coefficient equations and forces.

Lift Equation: L = C_L imes rac{1}{2} ho U^2 S_{ref}
Drag Equation: D = C_D imes rac{1}{2} ho U^2 S_{ref}
Where: - $U$ = relative airspeed - ho = air density - $S_{ref}$ = reference area (typically plan area).

Consider an aircraft with specific characteristics flying at a cruise speed, examining lift generation, mass, AoA, and wing area needed for desired performance outputs.

This type of aircraft depends on buoyancy rather than lift, requiring air displacement to offset weight.
Types include non-rigid, semi-rigid, and rigid structures (e.g., blimps and airships).

Governed by Archimedes’ Principle, which states that an object immersed in fluid experiences an upward force equal to the weight of the fluid it displaces.
Example equations for buoyancy with respect to specific gas densities.

Equation of State: The relationship is described through the Ideal Gas Law: p = ho R T, where:** - $p$ = pressure - ho = density - $T$ = temperature - $R$ is the specific gas constant for air (287 [J kg-1 K-1]).

Density variations with altitude and temperature can be calculated using known formulas and applying ideal gas relationships across conditions.

The ISA provides a model of the atmosphere, detailing behavior and physical processes that vary through distinct layers up to outer space: 1. Troposphere: 0 - 11 km 2. Stratosphere: 11 - 50 km 3. Mesosphere: 50 - 90 km 4. Thermosphere: Beyond 90 km up to exosphere.

Understanding of the forces acting on aircraft during flight.
The principles governing lift, drag, and buoyancy as distinctive forms of flight dynamics.
Awareness of fluid property definitions and implications of the International Standard Atmosphere.