u8

Question 1

explain how a high density altitude results in bad performance for lift, thrust and power

Answer 1

less air molecules over wing = less lift
less air molecules for propeller to push back = less thrust
less air molecules to engine = less power

Question 2

what is Vx
- how does it change with an increase in altitude
- what is Vx at the absolute ceiling

Answer 2

most altitude gain in a given distance
high altitude = Vx increases
at absolute ceiling Vx = best L/D speed

Question 3

what is Vy
- how does it change with an increase in altitude
- what is Vy at the absolute ceiling

Answer 3

most altitude gain in a period of time
- high altitude = Vy increases
- at absolute ceiling Vy = best L/D speed

Question 4

why do lighter planes have lower Va

Answer 4

plane flies at low AoA when it’s lightweight so we don’t want to exceed the LF before reaching the critical AoA

Question 5

flying for range
- what is it
- is it affected by wind

Answer 5

distance we can fly per unit of fuel
yes -> headwind = slower ground speed = decrease range

Question 6

flying for endurance
- what is it
- is it affected by wind

Answer 6

time we can stay in the air with a given amount of fuel
not affected by wind

Question 7

t/f: indicated stall speed increases with altitude

Answer 7

FALSE

Question 8

indicated vs true stall speed
do either of them change with altitude

Answer 8

indicated stall speed always stays the SAME regardless of altitude because it’s due to the critical AoA
- you’ll stall at 15º AoA at sea level or 10 000 ft
- the only thing that changes indicated stall speed is the LF

true stall speed INCREASES with altitude
- less air molecules at 10 000 ft so need to fly faster to get the same amount of lift

Question 9

the faster the plane, the _____ the bank angle required to maintain a standard rate turn

Answer 9

steeper

Question 10

fast planes have a ______ turn radius and _____ rate of turn

slow planes have a ______ turn radius and _____ rate of turn

Answer 10

fast: large radius and small rate turn

slow: small radius and large rate turn

Question 11

wing loading equation

Answer 11

wing loading = total weight plane (lbs) / wing area (sq ft)

Question 12

high wing loading = _______ aspect ratio = ______ wing compared to body = _____ lift = _____ stall speeds

for _____ planes

Answer 12

high wing loading = low aspect ratio = small wing compared to body = less lift = high stall speeds

for fast planes

Question 13

low wing loading = _______ aspect ratio = ______ wing compared to body = _____ lift = _____ stall speeds

for _____ planes

Answer 13

low wing loading = high aspect ratio = large wing compared to body = more lift = low stall speeds

for slow planes

Question 14

planes with high wing loading have ________ takeoff and landing distances. why?

Answer 14

large to and landing distances because those planes need to go faster

Question 15

CRFI
0.1 =
1.0 =

Answer 15

0.1 = slippery
1.0 = dry