What is an aerofoil chord line?
What is an aerofoil chord line?
A straight line conecting the leading edge with the trailing edge of an aerofoil.
What is the speed of sound at sea level according to ISA?
What is the speed of sound at sea level according to ISA?
662 kts
Local speed of sound = 39 x √(Temperature in Kelvin)
15°C in Kelvin is (15 + 273) = 288
So the local speed of sound = 39 x √288 = 662 kts
What effect does a wet runway have on V1?
What effect does a wet runway have on V1?
V1 is lower when the runway is wet than when the runway is dry, because of the longer ASDR on a wet runway.
What is the typical range of an NDB?
What is the typical range of an NDB?
Average range over land 20 - 25 miles.
Range for an NDB can be calculated with:
2√power output in Watts = Range (Land) 3√ power output in Watts = Range (Water)
What are the benefits of a free turbine?
What are the benefits of a free turbine?
A free turbine is a turbine that is not directly connected to the compressor. This allows the compressor to rotate at a different speed than the turbine. Since the turbine speed is coupled with the propeller, this allows for the propeller to be maintained at a constant ideal speed.
Another advantage is that free turbine engines can be designed to be more compact than their single shaft counterparts
Why do we measure speed as a Mach number?
Why do we measure speed as a Mach number?
Mach number describes the speed of sound, which changes with the density of the medium it is travelling through.
When you reach the speed of sound, the compressibility effect creates a supersonic flow along the wing if you exceed a certain mach number.
This causes airflow separation and flutter.
It is therefore much safer and much easier to use a Mach number to express a limit at which compressibility effects start to tear the aircraft apart, as it is a constant value at all altitudes.
Does the N1 compressor produce thrust?
Does the N1 compressor produce thrust?
Yes, with the modern high bypass turbofans the N1 compressor works as a huge propeller, it takes a big mass of air and gives it a relative small acceleration.
Around 70% of the air will bypass the core of the engine, only 30% of air will be compressed further and will eventually go through the combustion chamber.
How much thrust comes from the N1 fan?
How much thrust comes from the N1 fan?
Depends on the engine.
In the case of the 737-800 CFM56, 27,300lbs total thrust at a ratio of 5.5:1
What do the abbreviations TSRA and MIFG mean?
What do the abbreviations TSRA and MIFG mean?
TSRA: Thunderstorm with rain
- MIFG: Shallow fog
How would you load an aircraft for max range?
How would you load an aircraft for max range?
The position of the CG directly influences the fuel consumption of an aircraft. An aft position of the CG makes the aircraft less stable, requiring less lift to be generated in both the horizontal stabilizer and wings, reducing the overall drag of the aircraft, and increasing the max range.
You want to load the the aircraft so that the CG is at, or as close as possible, to the aft limit (Without exceeding it).