Air tech

Question 0

Avgas 100/130 means?

Answer 0

100 normal octane

130 best octane if best lean

Question 1

ISA

Answer 1

1013.2 hPa (-1hPa/30ft)
15C (-1.98C/’000ft) temp lapse rate
Density 1.225 kg/m3

Question 2

Types of carb ice

Answer 2

Refrigeration ice from fuel vapourisation
Throttle ice from from Venturi
Impact ice in air inlet - note carb heat won’t solve, but is alternate air source

Question 3

Bernoulli theorem

Answer 3

Dynamic energy + static pressure = constant

As air speeds up in Venturi it gains dynamic pressure, so static pressure decreases.

Question 4

Oil type for Robin

Answer 4

20W50 dispersant oil
SAE100
Good engine should use 1/6 litre per hour

Question 5

V speeds

Answer 5

Vs0 - 48kts - stall speed flaps down power off
Vs1 - 57kts - stall speed flaps up power off
Vfe - 97kts - max speed flaps extended
Va - 129kts - max manoeuvring speed for full/abrupt control movement
Vno - 129kts - max structural cruising speed (end of green)
Yellow caution range - still air manoeuvre only
Vne - 155kts - never exceed speed (red line)

Question 6

Total drag comprises

Answer 6

Induced drag -from production of lift

Parasite drag - all other drag