Seminole Systems

Question 1

Ignition system?

Answer 1

Impulse coupling- provides rotation for hot spark (450rpm).

Question 2

High pitch, low rpm?

Answer 2

Nitrogen, spring, counter weights.

Question 3

Unfeathering accumulator?

Answer 3

Stores engine oil under pressure.

Brings the prop out of the feathered position and reduces wear and tear on the starter.

Question 4

Feathering time?

Answer 4

10-17 sec.

Question 5

Anti-feathering pins?

Answer 5

Prevents the prop from feathering during shutdown. Doesn’t allow below 950 rpm.

Question 6

Semi ailerons?

Answer 6

Differential frise- reduces adverse yaw, adds drag (parasite).

23 degrees up and 17 degrees down.

Question 7

Describe the landing gear system?

Answer 7

Hydraulically operated, electrically powered, tricycle landing gear.

12 volt reversible pump.

Question 8

What limitations are associated with the landing gear?

Answer 8

Vle- gear extended speed (140)
Vlo- gear operation speed (140)
Vret- gear retract speed (109)

Question 9

Where is the hydraulic fluid stored for the landing gear?

Answer 9

Baggage

Question 10

Do the brakes and gear use the same hydraulic fluid? Are they taken from the same place?

Answer 10

Yes. No, brakes is located in the nose.

Question 11

What holds the landing gear up?

Answer 11

Hydraulic pressure - below 1300 psi the pump goes on again.

Question 12

What turns off the gear hydraulic pump during retraction?

Answer 12

Pressure switch at 1800 psi.

Question 13

What turns the 3 green indicators?

Answer 13

Down limit switches.

Question 14

What keeps the gear down and locked?

Answer 14

Downlock hooks and springs.

Question 15

What causes the gear unsafe light to illuminate?

Answer 15

• gear not full up or down
• MAP below 14” with the gear up
• flaps more than 2nd or 3rd notch

Question 16

How long does it take for the gear to be retracted or extended?

Answer 16

6-7 seconds.

Question 17

Why is there a thermal relief valve?

Answer 17

Protects it from temperature and pressure changes (3000 psi) by releasing excess pressure as the airplane climbs or descends.

Question 18

Alternators?

Answer 18

Two 14 volt 70 ampere.

Question 19

Battery?

Answer 19

12 volt 35 ampere-hour

Question 20

Overheat switch?

Answer 20

Approx 450 degrees (+/- 80)

Question 21

Where does the combustion heater take fuel from and how much?

Answer 21

Left fuel selector, 1/2 gal/hr.

Question 22

What are the limitations of the AP?

Answer 22

• 185 kts max
• 80 kts min
• no more 25 degrees flaps
• prohibited TO/LND
• missed appch and go around
• CAT I only
• no SE appch
• 200 ft below
• manual must be on board

Question 23

What type of engine Seminole has?

Answer 23

2 engines: 180 HP 2700 RPM
O-360-A1H6 (LO- right)
4 cylinder 
Direct drive 
Full feathered
Air cooled
Horizontally opposed
Carbureted

Question 24

What type of oil?

Answer 24

MIL-L-22851 Ashless Dispersant

Question 25

What type of prop?

Answer 25

``` 2 blade hartzell Constant speed Hydraulically actuated Full feathering 72-74" ```

Question 26

Low pitch, high rpm?

Answer 26

Oil and aerodynamic twisting force

Question 27

Unfeathering time?

Answer 27

8-12 seconds

Question 27

Why is the landing gear retraction speed slower then the extension speed?

Answer 27

Because the nose wheel will unlock and ram air will push the nose wheel back into the wheel well.

Question 28

What does the left squat switch do?

Answer 28

Prevents accidental gear retraction on the ground.

Question 29

What does the right squat switch do?

Answer 29

Activates the stall warning. Starts the MX Hobbs time.

Question 30

What does the up-limit switch on the nose gear do?

Answer 30

Turns off the heater blower.

Question 31

Brakes systems?

Answer 31

Two single-disc, double-puck brake assemblies.

Question 32

Electrical system?

Answer 32

Negative-ground, dual-fed, split-bus system.

Question 33

What does the ACU (alternator control unit) do?

Answer 33

It uses a voltage regulator and a overvoltage relay. Regulators- maintain 14 volts between the two (load sharing). Relay- will take the alternator offline if exceeds 17 volts.

Question 34

Six bus bars which distribute electricity?

Answer 34

- Battery bus (clock, flight times) - Avionics bus #1 (comm nav 1, xponder, pitch trim) - Tie bus - Main bus (lights, pumps, starter, pitot heat) - Avionics bus #2 (comm nav 2) - Non-essential bus (cabin heater, vent, blower)