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DOWNLOADIssue No 66, 31 March 2025
By: Anthony O. Ives
Airspeed can be defined in different ways such as True Airspeed (TAS), Calibrated or Rectified Airspeed (CAS/RAS), Equivalent Airspeed (EAS), Indicated Airspeed (IAS) and Mach number. This article aims to describe the relationship between each of the airspeeds and how to convert between them using equations or a mechanical flight computer such as the CPR-5.
Numerical Intergration and Simpson's Rule
Issue No 65, 3 March 2025
By: Anthony O. Ives
Integration was introduced in an earlier article. One of the most useful applications of integration is determining areas or volumes specifically if you know the mathematical relationships of the bounding curves. However, this article looks at using numerical methods, which makes it possible for anyone even if you hate mathematical equations and integration to determine areas or volumes by simply taking a set of measurements around your odded shaped area or volume.
Introduction to Sail Aerodynamics
Issue No 64, 14 October 2024
By: Anthony O. Ives
Aerodynamics is as important in sailing as it is aviation more so than in any other application of aerodynamics. The sail functions as wing and parachute in a way with the exception that the aerodynamic forces are used to move the sailboat forward through the water instead as in as aircraft to fly. Probably not known to many people not familiar with sailing a sailboat can use the wind to move in any direction regardless of wind direction because of the sail's ability to function like an aircraft wing.
Issue No 63, 16 September 2024
By: Anthony O. Ives
CFD stands for Computational Fluid Dynamics a more accurate title might be Numerical Fluid Dynamics as CFD uses numerical methods to solve the complex equations of fluid dynamics via computing. CFD is useful in aircraft design as it allows you to calculate more accurately things like lift and drag however, it also good at determining more detail about aerodynamic behaviour in general. This blog articles hopes to introduce and discuss CFD including it's pros and cons as well as the fact sometimes it can be overkill and the simpler aerodynamics can give just as good results.
Hydrodynamics: Wave Generating Drag
Issue No 62, 20 May 2024
By: Anthony O. Ives
In a previous article, buoyancy was looked at when sizing helicopter floats but the same princple applies to anything including boat hulls. However, when a boat or float starts moving through the water it generates a resistance force similar to an aircraft which can also be called drag generally referred to as hydrodynamic drag. There are two main types of hydrodynamic drag, skin friction drag and wave generating drag.
Boats and Floats: Archimedes Princple
Issue No 61, 6 May 2024
By: Anthony O. Ives
Boats or building a set of floats is a simple, fun way to use mathematics to build something accurately to do exactly what you want it to do. Archmedes principle defines how and why a objects floats. Archimedes principle states that for an object to float it must displace a volume of fluid equivalent to the weight of object which is partially or fully submerged in the fluid. Archimedes principle does not just apply to boats it also applies lighter than air aircraft such as airships and balloons.
Issue No 60, 22 April 2024
By: Anthony O. Ives
Traditionally before computers engineering components were usually designed with pencil and paper. The disadvantage of designing using pencil and paper if the design changes it requires a lot of work to redo the drawing, even small design changes can require a lot of work. With the development of computers, software programs where created to design in same way as pencil and paper was used. These software programs are usually referred as CAD (Computer Aided Design) packages.
Issue No 59, 8 April 2024
By: Anthony O. Ives
The aircraft structure is obviously an important part of the aircraft without it the aircraft could not fly. Aerodynmics and Aircraft Structural Design is the two core topics in aeronautical engineering with aeronautical engineers specialising in one of these topics. Aeronautical engineers specialising in aircraft structures are usually called stress engineers. Unlike other structures an aircraft most be designed to be lightweight but also withstand all the forces applied to the structure without failing. Aircraft structural failure in most cases can have fatal consequences.
Issue No 58, 25 March 2024
By: Anthony O. Ives
Aviation is one of the most regulated if not the most regulated activity and industry in the world. The regulation of aviation is very complex generating complicated legal requirements. Most countries base their aviation regulations on those defined by the Chicago convention in 1944 and establishment of ICAO (International Civil Aviation Organisation) a UN (United Nations) organisation set up to make and manage international aviation law and regulations.
Helicopter Hazard Flight Conditions
Issue No 57, 11 March 2024
By: Anthony O. Ives
The two most common hazards of engine failure and vortex ring were covered separately and in more detail previously. The less common but possibly just as serious and dangerous hazardous flight conditions are covered in this article. Some hazardous flight conditions such as ground resonance can only experienced in certain helicopter designs so the type of helicopter the hazard is most relevant to will be described as will be the most suitable recovery procedure.
Issue No 56, 26 February 2024
By: Anthony O. Ives
Autorotation is the emergency procedure to land a helicopter safely after an engine failure, the basic procedure was covered in an earlier article. This article will discuss some more advanced procedures that will allow the pilot to vary his chosen touchdown point depending where the engine failure occurs.
Helicopter Confined Area Operations, Low and High Reconnaissance
Issue No 55, 5 February 2024
By: Anthony O. Ives
A helicopter's main advantage over fixed wing aircraft is that it can land anywhere. The helicopter could be referred as the off road vehicle among other aircraft. However, landing anywhere comes with lots of problems due to unprepared areas containing lots of hazards. Therefore all helicopter pilots train to do a landing site reconnaissance also known as a 'Recce'.
Issue No 54, 22 January 2024
By: Anthony O. Ives
At the time writing the environmental impact of transportation technology such as cars, aircraft, etc was getting a lot of attention in the media. Aircraft noise is also grouped in with environmental impact even though it does not environmentally pollute it is considered a form of pollution somethings referred to as noise pollution. Aircraft noise is one of the reasons why airports face resistance when there are plans to expand them usually from residents who live beside them. Helicopters are perceived as being very noisy however, compared with jet aircraft, a jet aircraft would be a lot noisier than helicopter. Helicopters other the hand operate at lower altitudes so they are more noticeable as being noisy.
Issue No 53, 8 January 2023
By: Anthony O. Ives
Search and rescue operations is something helicopters are very good at, you could say they were nearly invented to do search and rescue operations if you consider Igor Sikorsky's quote “If you are in trouble anywhere in the world, an airplane can fly over and drop flowers, but a helicopter can land and save your life.”. However, even fixed wing aircraft in co-operation with a ground units greatly improve the chance of a search and rescue operation being successfully. Before the helicopters were a practical search and rescue asset, a typical airborne search and rescue operation would involve searching for survivors from the air, and then when survivors are located parachuting rescue personnel into that location. The rescue personnel would then provide medical treatment if necessary and arrange extraction usually by ground. We will review how rescue operations have advanced from parachute operations to helicopter operations and look at how tiltrotor aircraft could possibly improve search and rescue operations in the future.
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