THE VERTICAL SPEED INDICATOR

Question 1

1. 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:

Answer 1

a. a combination of time lag and manoeuvre induced errors.

Question 2

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

Answer 2

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

Question 3

3. In the IVSI, lag error:

Answer 3

b. is virtually overcome by using a special dashpot accelerometer assembly.

Question 4

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

Answer 4

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

Question 5

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

Answer 5

b. a slight climb.

Question 6

6. If the static vent becomes blocked during a climb:

Answer 6

c. the VSI will return to zero.

Question 7

7. In conditions of clear air turbulence:

Answer 7

b. the IVSI is more sensitive.

Question 8

8. Change of temperature as an aircraft climbs or descends:

Answer 8

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

Question 9

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

Answer 9

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