Vayudoot Aviation

1. Because the VSI measures rates of change of static pressure and not actual values of static pressure, position error:

may cause errors in VSI indications whenever airspeed is changed, if at the same time there is a change in position error.

may cause errors in VSI indications whenever airspeed is changed, even if there is no change in position error.

never affects VSI indications

may cause errors in the VSI during the take-off run.

2. If the static vent becomes blocked during a climb

the VSI will stop at the rate of climb of the aircraft at the time of blockage.

the VSI will return to zero.

the VSI will indicate an increasing rate of climb

the VSI will indicate a decreasing rate of climb.

3. Change of temperature as an aircraft climbs or descends

will affect VSI readings whenever temperature lapse rate differs from standard conditions.

has no effect on the VSI as only static pressure is used in this instrument.

may be allowed for by use of tables or computer.

is compensated at the metering unit by means of a capillary and orifice

4. The vertical speed indicator indications may be in error for some seconds after starting or finishing a climb or descent. The error is a result of:

manoeuvre induced errors only.

a combination of time lag and manoeuvre induced errors.

a combination of position error and manoeuvre induced errors.

a combination of time lag and instrument error.

5. The advantage of having the VSI dial presentation in logarithmic spacing rather than in linear spacing is that

a greater range of rates of climb and descent is shown.

readings are instantaneous.

at low rates of climb or descent the pointer movement is much larger and so is more easily read.

the internal mechanism is simplified by deletion of the calibration choke.

6. Permissible limits of accuracy of the VSI are ....... when ....... within a temperature range of ....... and ....... outside this range

+ 200 fpm, on the ground, -20°C to +50°C, + 300 fpm

+ 250 fpm, on the ground, -20°C to +50°C, + 300 fpm

+ 200 fpm, at any height, -20°C to +30°C, + 300 fpm

+ 250 fpm, at any height, -20°C to +50°C, + 300 fpm

7. When entering a steep turn, an IVSI is likely to show

a slight descent.

no change in altitude.

a slight climb.

a slight descent at high airspeed only.

8. During a missed approach and go-around procedure the change of aircraft attitude plus raising of the landing gear and changing of flap settings can cause short term unpredictable errors in certain instruments. The instruments most likely to be affected in this case are

the machmeter, airspeed indicator, altimeter and vertical speed indicator

the airspeed indicator, machmeter and vertical speed indicator.

the altimeter, artificial horizon and vertical speed indicator.

the vertical speed indicator, airspeed indicator and altimeter.

9. In conditions of clear air turbulence

both types will react the same.

the standard VSI is more sensitive.

the IVSI is more sensitive.

the vertical acceleration pump will not be affected.

10. In the IVSI, lag error:

is virtually overcome by using a special dashpot accelerometer assembly.

is only overcome when initiating a climb or descent.

is overcome by the use of logarithmic presentation.

is overcome by feeding a sample of static pressure to the case and delaying it to the capsule.

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Questions for VERTICAL SPEED INDICATOR