In a standard atmosphere and at the sea level the calibrated airspeed CAS is ?
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The parameter that determines the relationship between EAS and TAS is ?
With CAS and pressure altitude we can deduce ?
Speed of sound proportional to The square root of absolute temperature. 
The total air temperature tat The temperature resulting from aircraft motion in air. total air temperature tat the temperature that would be measured a temperature probe if all of kinetic energy of air resulting from aircraft's motion was totally recovered this can never be very accurately measured because 100% recovery of kinetic energy impossible a number of reasons. 
During a climb if total pressure head rapidly clogged up ice sensed total pressure remains constant and The static pressure decreases implying an increasing ias. 'total pressure hea = pitot tube (it senses dynamic pressure + static pressure) while climbing static pressure decreases if total pressure head clogged up ice airspeed indicator will then show an increasing speed indicated airspeed = (dynamic pressure + static pressure) static pressure since question states the sensed total pressure remains constant value '(dynamic pressure + static pressure)' does not change only 'static pressure' reduces consequence an increasing indicated airspeed. 
The static air temperature sat The ambient outside air temperature. in aviation terminology outside air temperature (oat) or static air temperature (sat) refers to temperature of air around an aircraft but unaffected the passage of aircraft through it. Question 45-8
The limits of green scale of an airspeed indicator are The ambient outside air temperature. in aviation terminology outside air temperature (oat) or static air temperature (sat) refers to temperature of air around an aircraft but unaffected the passage of aircraft through it. Question 45-9
Concerning pitot and static system static pressure error varies according to 1 altimeter setting2 speed3 angle of attackthe combination that regroups all of correct statements The ambient outside air temperature. the static port will be affected speed (compressibility effect) by angle of attack (air flow aournd fuselage will change) altimeter setting irrelevant to pressure sensed at static port. Question 45-10
The alternate static source used When static ports become blocked. the alternate static vent of an unpressurised aircraft senses air pressure in flight deck/cockpit in flight air outside flight deck accelerates over aircraft canopy (venturi effect) this causes a drop in static pressure air will always flow from a high pressure to a low pressure so air in flight deck flows outside this flow to outside causes pressure in cabin to be lower than undisturbed static pressure around aircraft. Question 45-11
The machmeter subject to position error this error varies according to 1 angle of attack2 oat3 tasthe combination that regroups all of correct statements When static ports become blocked. position (pressure) error varies with angle of attack speed but not with temperature. Question 45-12
The data output from adc are 1 barometric altitude2 mach number3 cas4 tas5 satthe combination that regroups all of correct statements When static ports become blocked. position (pressure) error varies with angle of attack speed but not with temperature. Question 45-13
An aeroplane cruising at fl 60 with a tas of 100 kt in standard atmosphere in these conditions 1 tas approximately 10% higher than ias2 difference between eas and cas negligible3 speed displayed on airspeed indicator a cas if position error and instrument error are zerothe combination regrouping all of correct statements When static ports become blocked. tas = ias + 2% per 1000 ft altitude eas cas corrected compressibility at low speed low altitude compressibility negligeable cas ias corrected position instrument errors. Question 45-14
The tas obtained from cas correcting the following errors 1 instrument2 compressibility3 position4 densitythe combination that regroups all of correct statements When static ports become blocked. tas = ias + 2% per 1000 ft altitude eas cas corrected compressibility at low speed low altitude compressibility negligeable cas ias corrected position instrument errors. Question 45-15
The cas obtained from ias correcting the following errors 1 position2 compressibility3 instrument4 densitythe combination that regroups all of correct statements When static ports become blocked. tas = ias + 2% per 1000 ft altitude eas cas corrected compressibility at low speed low altitude compressibility negligeable cas ias corrected position instrument errors. Question 45-16
The eas obtained from cas correcting the following errors 1 position2 compressibility3 instrument4 densitythe combination that regroups all of correct statements When static ports become blocked. tas = ias + 2% per 1000 ft altitude eas cas corrected compressibility at low speed low altitude compressibility negligeable cas ias corrected position instrument errors. Question 45-17
If static ports are completely clogged up ice during a climb vertical speed indicator shows When static ports become blocked. tas = ias + 2% per 1000 ft altitude eas cas corrected compressibility at low speed low altitude compressibility negligeable cas ias corrected position instrument errors. Question 45-18
Eas equal to Cas corrected compressibility error. tas = ias + 2% per 1000 ft altitude eas cas corrected compressibility at low speed low altitude compressibility negligeable cas ias corrected position instrument errors. Question 45-19
During a climb at a constant mach number below tropopause in standard atmosphere Cas corrected compressibility error. for those questions use very simple 'ertm' diagram the mach line vertical because question states climb at a constant mach number ertm e as/r as(rectified air speed or cas)/t as/m ach. Question 45-20
When climbing at a constant cas through an isothermal layer mach number Cas corrected compressibility error. for those questions use very simple 'ertm' diagram the cas line vertical because question states climbing at a constant cas ertm e as/r as(rectified air speed or cas)/t as/m ach tas will increase since density decreases with altitude mach = tas / local speed of sound local speed of sound varies only with temperature the question states 'isothermal layer' (temperature remains constant) thus lss increases. Question 45-21
If pilot increases reference pressure using sub scale setting knob altitude indicated the altimeter Cas corrected compressibility error. you have to turn altimeter setting adjustement knob in a clockwise direction to increase indicated pressure this will increase indicated altitude. Question 45-22
The alternate static source of a light non pressurized aircraft located in flight deck when used static pressure sensed likely to be Lower than ambient pressure due to aerodynamic suction. the alternate static vent of an unpressurised aircraft senses air pressure in flight deck/cockpit in flight air outside flight deck accelerates over aircraft canopy (venturi effect) this causes a drop in static pressure air will always flow from a high pressure to a low pressure so air in flight deck flows outside this flow to outside causes pressure in cabin to be lower than undisturbed static pressure around aircraft. Question 45-23
Eas can be obtained from following data Cas pressure altitude. eas cas corrected compressibility which you would work out from pressure altitude with eas density altitude we can deduce tas. Question 45-24
Cas equal to Ias corrected position instrument errors. an airspeed indicator displays ias the error in altimeter readings caused the variation of static pressure near source known as position error instrument error refers to combined accuracy precision of a measuring instrument or difference between actual value the value indicated cas ias corrected position instrument errors. Question 45-25
Eas equal to Ias corrected position instrument compressibility errors. eas cas corrected compressibility cas ias corrected position instrument errors therefore eas ias corrected position instrument compressibility errors position error error in altimeter readings caused the variation of static pressure near source instrument error refers to combined accuracy precision of a measuring instrument or difference between actual value the value indicated compressibility the error in readings of a differential pressure type airspeed indicator due to compression of air on forward part of pitot tube component moving at high speeds. Question 45-26
The altimeter subject to static pressure error this error results from Incorrect pressure sensing caused disturbed airflow around static ports. eas cas corrected compressibility cas ias corrected position instrument errors therefore eas ias corrected position instrument compressibility errors position error error in altimeter readings caused the variation of static pressure near source instrument error refers to combined accuracy precision of a measuring instrument or difference between actual value the value indicated compressibility the error in readings of a differential pressure type airspeed indicator due to compression of air on forward part of pitot tube component moving at high speeds. Question 45-27
The machmeter subject to position error this error results from Incorrect pressure sensing caused disturbed airflow around pitot tube and/or static ports. eas cas corrected compressibility cas ias corrected position instrument errors therefore eas ias corrected position instrument compressibility errors position error error in altimeter readings caused the variation of static pressure near source instrument error refers to combined accuracy precision of a measuring instrument or difference between actual value the value indicated compressibility the error in readings of a differential pressure type airspeed indicator due to compression of air on forward part of pitot tube component moving at high speeds. Question 45-28
The eas obtained from ias correcting the following errors 1 instrument2 position3 density 4 compressibilitythe combination that regroups all of correct statements Incorrect pressure sensing caused disturbed airflow around pitot tube and/or static ports. eas cas corrected compressibility cas ias corrected position instrument errors therefore eas ias corrected position instrument compressibility errors position error error in altimeter readings caused the variation of static pressure near source instrument error refers to combined accuracy precision of a measuring instrument or difference between actual value the value indicated compressibility the error in readings of a differential pressure type airspeed indicator due to compression of air on forward part of pitot tube component moving at high speeds. Question 45-29
When descending at a constant cas through an isothermal layer mach number Incorrect pressure sensing caused disturbed airflow around pitot tube and/or static ports. for those questions use very simple 'ertm' diagram the cas line vertical because question states climbing at a constant cas ertm e as/r as(rectified air speed or cas)/t as/m ach tas will decrease since density increases with altitude mach = tas / local speed of sound local speed of sound varies only with temperature the question states 'isothermal layer' (temperature remains constant) thus lss decreases. Question 45-30
In standard atmosphere at sea level eas Incorrect pressure sensing caused disturbed airflow around pitot tube and/or static ports. True air speed (tas) obtained from equivalent air speed (eas) correcting density error thus in a standard atmosphere at sea level eas = tas. Question 45-31
The alternate static source of a light non pressurized aircraft located in flight deck as alternate static source opened vertical airspeed indicator may Indicate a momentary climb. the terms 'vertical speed indicator' or 'vsi' or 'vertical airspeed indicator' are used the variometer an alternate source static pressure provided in some airplanes in event static ports become blocked this source usually vented to pressure inside cockpit because of venturi effect of flow of air over cockpit this alternate static pressure usually lower than pressure provided the normal static air source when alternate static source used following differences in instrument indications usually occur altimeter will indicate higher than actual altitude airspeed will indicate greater than actual airspeed the vertical speed will indicate a climb while in level flight. Question 45-32
Concerning pitot and static system static pressure error Is caused disturbed airflow around static ports. the terms 'vertical speed indicator' or 'vsi' or 'vertical airspeed indicator' are used the variometer an alternate source static pressure provided in some airplanes in event static ports become blocked this source usually vented to pressure inside cockpit because of venturi effect of flow of air over cockpit this alternate static pressure usually lower than pressure provided the normal static air source when alternate static source used following differences in instrument indications usually occur altimeter will indicate higher than actual altitude airspeed will indicate greater than actual airspeed the vertical speed will indicate a climb while in level flight. Question 45-33
The output data from adc are used 1 transponder2 efis3 automatic flight control system afcs the combination that regroups all of correct statements Is caused disturbed airflow around static ports. the terms 'vertical speed indicator' or 'vsi' or 'vertical airspeed indicator' are used the variometer an alternate source static pressure provided in some airplanes in event static ports become blocked this source usually vented to pressure inside cockpit because of venturi effect of flow of air over cockpit this alternate static pressure usually lower than pressure provided the normal static air source when alternate static source used following differences in instrument indications usually occur altimeter will indicate higher than actual altitude airspeed will indicate greater than actual airspeed the vertical speed will indicate a climb while in level flight. Question 45-34
Maintaining cas and flight level constant a fall in ambient temperature results in Lower tas because air density increases. lower temperature means an increase of air density (air mass contracting) it similar to a descent (to a lower altitude) you can use 'ertm' diagram the cas line vertical because cas constant ertm e as/r as(rectified air speed or cas)/t as/m ach cas = 1/2 rho v² density will increase during descent in order to maintain constant cas only v (tas) can be reduced. Question 45-35
If oat increases whilst maintaining a constant cas and flight level Mach number remains constant. if oat increases density decreases (with higher temperature air expanding density reduced) cas = 1/2 x density x tas² cas constant density decreases then tas must increase mach = tas / local speed of sound local speed of sound varies only with temperature (lss varies with square root of absolute temperature formula lss = 39 x square root of (oat+273)) thus if tas increases lss increases mach number remains constant. Question 45-36
If oat decreases whilst maintaining a constant cas and flight level Mach number remains constant. if oat decreases density increases (with lower temperature air contracting density increased) cas = 1/2 x density x tas² cas constant density increases then tas must decrease mach = tas / local speed of sound local speed of sound varies only with temperature (lss varies with square root of absolute temperature formula lss = 39 x square root of (oat+273)) thus if tas decreases lss decreases mach number remains constant. Question 45-37
The adc uses following parameters as input data Static pressure total pressure tat. if oat decreases density increases (with lower temperature air contracting density increased) cas = 1/2 x density x tas² cas constant density increases then tas must decrease mach = tas / local speed of sound local speed of sound varies only with temperature (lss varies with square root of absolute temperature formula lss = 39 x square root of (oat+273)) thus if tas decreases lss decreases mach number remains constant. Question 45-38
The total pressure head comprises a mast which moves its port to a distance from aircraft skin in order To locate it outside boundary layer. if oat decreases density increases (with lower temperature air contracting density increased) cas = 1/2 x density x tas² cas constant density increases then tas must decrease mach = tas / local speed of sound local speed of sound varies only with temperature (lss varies with square root of absolute temperature formula lss = 39 x square root of (oat+273)) thus if tas decreases lss decreases mach number remains constant. Question 45-39
In case of static blockage airspeed indicator Under reads in climb over reads in descent. the asi a sensitive differential pressure gauge which measures promptly indicates difference between pitot (total pressure) static pressure (total pressure static pressure = dynamic pressure) these two pressures are equal when aircraft parked on ground in calm air when aircraft moves through air pressure on pitot line becomes greater than pressure in static lines this difference in pressure registered the airspeed pointer on face of instrument thus while descending total pressure increases* the static pressure (from static source) does not your airspeed indicator will over read *while descending density increases so total pressure increases while climbing total pressure decreases the static pressure (from static source) does not your airspeed indicator will under read. Question 45-40
The machmeter subject to position error this error concerns Pitot tubes static ports. the alternate static vent of an unpressurised aircraft senses air pressure in flight deck/cockpit in flight air outside flight deck accelerates over aircraft canopy (venturi effect) this causes a drop in static pressure air will always flow from a high pressure to a low pressure so air in flight deck flows outside this flow to outside causes pressure in cabin to be lower than undisturbed static pressure around aircraft.
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