Aircraft engine performance
Aircraft engine performance refers to factors including thrust or shaft power for fuel consumed, weight, cost, outside dimensions and life.
[1] Aircraft engines are part of the propulsion system of an airplane, helicopter, rocket or UAV which produce rotary power transferred to a propeller or kinetic energy as a high-velocity gas exhaust stream.
Thrust,[1] Shaft power,[1] Fuel consumption,[1] Weight,[1] Cost,[1] Installation envelope,[1] Overhaul life,[1] Operability, Noise, Exhaust pollutants.
Small turboprop and business aircraft may be approved for a limited running time on avgas to allow refuelling at remote airstrips with no jet fuel supply.
Aviation gasoline is highly volatile and very flammable, with a low flash point,[5] which makes it unsuitable for use in gas turbine engines.
[8] TEL has been banned by the European Union for automotive use due to environmental concerns, but remains approved for use in aircraft.
In order to power rockets, a fuel and an oxidiser are mixed within the combustion chamber, producing a high energy propulsive exhaust as thrust.
The main uses for rocket fuel are for space shuttle boosters in order to propel the craft out of the atmosphere, or for missiles.
There are a multitude of personal UAV's and drones available for purchase without a licence or age restriction globally, capable of high speed manoeuvres and agile flight characteristics.
Currently, pressurised tanks to hold the hydrogen fuel with sufficient volume and a low enough weight are not available for large commercial aircraft, but have been successfully implemented on smaller personal aircraft such as the Boeing Fuel Cell Demonstrator by Boeing Phantom Works and on launch rockets for space shuttles when stored cryogenically.
Hydrogen fuel cells create electrical power through hydrolysis and are in various stages of research for applications in environmentally friendly engines as they emit no toxic exhaust.
Researchers from MIT (Massachusetts Institute of Technology) have developed an ion drive propulsion system with no moving parts.
This new form of aircraft propulsion would be completely silent and require far less maintenance than conventional fossil-fuel powered engines.
[13] Atmospheric conditions are an important consideration in the analysis of the factors contributing to differing aircraft engine performance.
However, cooling capacity will decline on both combustion and electric motors at high altitude due to the lower density of air.
This phenomenon is why the operating limit of helicopters is constrained, as propeller thrust returns to a value of 0 when the air becomes too thin at high altitude.
Pilots account for the ambient temperature on the day of a flight in order to calculate the takeoff distance required.
With cold temperatures, air is denser and a larger mass of air/fuel mixture is combusted, leading to higher efficiency and greater power.
If the hail is severe enough, engine inlet guide vanes or compressor blades can bend or break under impact.
The glass-like silicate compound found in volcanic ash has a lower melting point than the combustion temperature of fuel and air in a jet engine.
