At Reference In a pressurized aircraft whose cabin altitude is 8000 ft a crack in a cabin window makes it necessary to reduce the differential pressure to 5 psi The flight level to be maintained in ? Understand > airport
From table it can be seen that pressure at 8000 ft 10 92 psi
now we've been told because of crack in cabin window we can maintain a pressure differential of 5 psi
therefore air outside can only be 5 psi less than that inside cabin (ie 10 92 5 = 5 92)
again from table altitude where we get closest to 5 92 approximately 23000 ft (fl230).
The pressurisation system of an aeroplane ?
The pressurisation system of an aeroplane Has capability to maintain a cabin pressure higher than ambient pressure. From table it can be seen that pressure at 8000 ft 10 92 psi
now we've been told because of crack in cabin window we can maintain a pressure differential of 5 psi
therefore air outside can only be 5 psi less than that inside cabin (ie 10 92 5 = 5 92)
again from table altitude where we get closest to 5 92 approximately 23000 ft (fl230).
In a turbo compressor air conditioning system bootstrap system the supply of air behind the primary heat exchanger is ?
In a turbo compressor air conditioning system bootstrap system supply of air behind primary heat exchanger Compressed passed through a heat exchanger then across an expansion turbine. The term bootstrap refers to a self sustaining process that proceeds without external help. The purpose of cabin air flow control valves in a pressurization system to Maintain a constant sufficient mass air flow to ventilate cabin minimise cabin pressure surges. Cabin pressurization controlled during all phases of airplane operation the cabin pressure control system
the system uses bleed air supplied to distributed the air conditioning
system pressurization ventilation are controlled modulating outflow valve the overboard exhaust valve
pressurization outflow
cabin air outflow controlled the outflow valve the overboard exhaust valve a small amount also exhausted through toilet galley vents miscellaneous fixed vents by seal leakage
outflow valve
the outflow valve the overboard exhaust exit the majority of air
circulated through passenger cabin passenger cabin air drawn through foot level grills down around aft cargo compartment where it provides heating is discharged overboard through outflow valve
note the answer discharge cabin air to atmosphere if cabin pressure rises above selected altitude we are talking about pressure relief valves who provide safety pressure relief limiting differential pressure to a maximum of 9 1 psi a negative relief valve prevents external atmospheric pressure from exceeding internal cabin pressure. If pressure in cabin tends to become lower than outside ambient air pressure Negative pressure relief valve will open. All pressurised aircraft have negative pressure relief valves that will open enable cabin pressure to increase at same rate as ambient pressure should cabin/ambient differential try to go negative
aircraft are structurally designed a positive differential (cabin pressure higher than ambient)
under normal operation pressure controller can cope but in emergencies negative pressure relief valves will function. Cabin air cs 25 aeroplanes usually taken from The high pressure compressor from low pressure compressor if necessary. The air taken from engine at a suitable pressure temperature from compressors on a modern high bypass engine that would mean high pressure compressor but it really dependant on type. Under normal flight conditions cabin pressure controlled Regulating discharge of air through outflow valve(s). The air taken from engine at a suitable pressure temperature from compressors on a modern high bypass engine that would mean high pressure compressor but it really dependant on type. 8 Pneumatic mechanical ice protection systems are mainly used Regulating discharge of air through outflow valve(s). Pneumatic mechanical ice protection systems are mainly used wings more precisely leading edge wing tail surfaces
this a de icing system only it has to be turn on after a bit of ice has build up
when activated rubber boots are pressurized with air they expand breaking ice off leading edge surfaces
. 9 With regard to pneumatic mechanical devices that afford ice protection only correct statement They can only be used as de icing devices. Pneumatic mechanical ice protection systems are mainly used wings more precisely leading edge wing tail surfaces
this a de icing system only it has to be turn on after a bit of ice has build up
when activated rubber boots are pressurized with air they expand breaking ice off leading edge surfaces
. 10 Concerning electrically powered ice protection devices only true statement On modern aircraft electrically powered thermal devices are used to prevent icing on small surfaces (pitot static windshield ). Pneumatic mechanical ice protection systems are mainly used wings more precisely leading edge wing tail surfaces
this a de icing system only it has to be turn on after a bit of ice has build up
when activated rubber boots are pressurized with air they expand breaking ice off leading edge surfaces
. 11 The elements specifically protected against icing on transport aircraft are 1 engine air intake and pod 2 front glass shield 3 radome 4 pitot tubes and waste water exhaust masts 5 leading edge of wing 6 cabin windows 7 trailing edge of wings 8 electronic equipment compartment the combination regrouping all correct statements On modern aircraft electrically powered thermal devices are used to prevent icing on small surfaces (pitot static windshield ). Pneumatic mechanical ice protection systems are mainly used wings more precisely leading edge wing tail surfaces
this a de icing system only it has to be turn on after a bit of ice has build up
when activated rubber boots are pressurized with air they expand breaking ice off leading edge surfaces
. 12 The wing anti ice system has to protect The leading edge or slats either partially or completely. In jet aeroplanes thermal anti ice system primarily supplied bleed air from engines (bleed air from hp compressor)
the wing anti ice system has to protect leading edge or slats either partially or completely engine intake frontal area of elevator the vertical stabiliser. 13 In jet aeroplanes 'thermal anti ice system' primarily supplied Bleed air from engines. In jet aeroplanes thermal anti ice system primarily supplied bleed air from engines (bleed air from hp compressor)
the wing anti ice system has to protect leading edge or slats either partially or completely engine intake frontal area of elevator the vertical stabiliser. 14 The icing system which mostly used the wings of modern turboprop aeroplanes Bleed air from engines. In jet aeroplanes thermal anti ice system primarily supplied bleed air from engines (bleed air from hp compressor)
the wing anti ice system has to protect leading edge or slats either partially or completely engine intake frontal area of elevator the vertical stabiliser. 15 Concerning sequential pneumatic impulses used in certain leading edge icing devices one can affirm that 1 they prevent ice formation 2 they are triggered from flight deck after icing has become visible 3 a cycle lasts more than ten seconds 4 there are more than ten cycles per second the combination which regroups all correct statements Bleed air from engines. In jet aeroplanes thermal anti ice system primarily supplied bleed air from engines (bleed air from hp compressor)
the wing anti ice system has to protect leading edge or slats either partially or completely engine intake frontal area of elevator the vertical stabiliser. 16 Generally large aeroplanes electrical heating ice protection used on Bleed air from engines. In jet aeroplanes thermal anti ice system primarily supplied bleed air from engines (bleed air from hp compressor)
the wing anti ice system has to protect leading edge or slats either partially or completely engine intake frontal area of elevator the vertical stabiliser. 17 The wing ice protection system currently used most large jet transport aeroplanes a Bleed air from engines. On most modern jet aeroplanes thermal anti ice system primarily supplied bleed air from engines (bleed air from hp compressor)
the wing anti ice system has to protect leading edge or slats either partially or completely engine intake frontal area of elevator the vertical stabiliser. 18 Pneumatic mechanical devices that provide ice protection Are usually used as de icing devices. On most modern jet aeroplanes thermal anti ice system primarily supplied bleed air from engines (bleed air from hp compressor)
the wing anti ice system has to protect leading edge or slats either partially or completely engine intake frontal area of elevator the vertical stabiliser. 19 The anti icing method the wings of large jet transport aeroplanes most commonly used in flight Thermal (use of hot air). In large jet aeroplanes thermal anti ice system primarily supplied bleed air from engines (bleed air from hp compressor)
the wing anti ice system has to protect leading edge or slats either partially or completely engine intake frontal area of elevator the vertical stabiliser. 20 Windshield heating of a transport aeroplane Essential to improve strength of cockpit windows. Windshield heating system employs a windscreen of special laminated construction heated electrically to prevent not only formation of ice mist but also to improve impact resistance of windscreen at low temperatures. Exclusive rights: Content under private and protected license, reproduction prohibited and prosecuted.
