midterm 2 Flashcards
when and where did the first trans oceanic supersonic passenger flight took off
London Heathrow Airport in 1976
flight that is faster than the speed of sound.
super sonic flight
The ratio of an aircraft’s speed divided by the speed of sound is known
Mach number
- The Concorde cruised at about
Mach ____when not over land. Some
military aircraft fly at even higher supersonic speeds.
2.02 (roughly twice the speed of sound)
Flight faster than Mach 5 is known as
Hypersonic
moves. The
disturbance includes air flow around the aircraft as well as traveling pressure
waves that humans perceive as____
sound
In subsonic flight, sound waves may be
emitted in
all directions
In supersonic flight, because the aircraft is flying faster
than sound travels, all disturbances are
behind the aircraft
Disadvantages of High-Speed Flights
Cost
Noise
Profitability
how many Concorde were made
20
14 for british airways and air france
6 for prototypes and testing
advantage of high speed flights
speed and range
is the main attraction for supersonic flights
however due to air traffic constraints, a supersonic aircraft will not be able to
achieve meaningful time savings for flight less than 800 NM.
speed
is caused by the desynchronization of the normal
sleep and wakefulness cycle of the body with local time. The problem presents
itself to travelers as lowered efficiency and malaise, the inability to sleep during
local sleeping hours after a journey and fatigue when one is re quired to be
alert. This problem is even more pressing for the crew who have to rest in an
allotted time so as to be fit to fly the aircraft again.
Circadian dysrhythmia
HIGH SPEED FLIGHT LIMITATIONS
Circadian dysrhythmia
high altitude
Radiation
4-in. diameter
hole would cause the cabin altitude to rise to
30000ft
6-in. hole
42,500 ft
8 in. diameter hole,
53,500 ft
It has been estimated that an
average dosage of can be expected on transatlantic routes.
1-5 mrem/hr
The International Commission on Radiation Dosage advises a limit of
5
rem/year
trans siberian flight radiation
3.9 mrem per flight
The intensity of the boom
will depend on the
size shape and weight of an aircraft
a shock wave of pressure created by compression of sound waves
as the air is displaced by the airframe traveling at or above Mach 1.0.
sonic boom
The Concorde was louder than the aircraft
meeting ICAO’s
stage 2 standards.,
is used to refer to the shocks caused by the supersonic flight of
an aircraft.
sonic boom
Newly designed aircraft certified after December 31, 2017, must
meet US Stage 5 standards which requires aircraft to be at least 7 dB quieter
than required by Stage 4 noise standards or 17 dB less than required by the
Stage 3 standards cumulatively across three noise measurements (flyover,
sideline, approach). As a comparison to Stage 2 compliant aircrafts, the
sound produced by Stage 5 compliant aircrafts are on the order of one-
fourth the sound intensity of aircraft operating on Stage 2 standards.
explain sonic boom relation 1. Aircraft weight, shape and length
The bigger the aircraft is, the more air molecules push aside. Thus, a
big aircraft will produce a stronger sonic boom.
Aircraft altitude
The altitude of the aircraft and the strength of the sonic boom are
reciprocal. As the altitude increases, the strength of the sonic boom
decreases.
Aircraft maneuvers
Maneuvers such as pushovers, S-turns and accelerating can amplify
the intensity of the shock wave. Hills, valleys and other topographic features
can create multiple reflections of shock waves thus affecting intensity.
Location in sonic boom carpet
Special topographic features in each area such as mountains, hills
and valleys can create multiple reflections of shock waves thus affecting
intensity.
