POH 4.7 Landing Gear

Question 1

POH4.7.1 Operation

Question 2

How does the Seneca II increase cruise speed, climb and other performance?

Answer 2

Equipped with hydraulically operated, fully retractable, tricycle landing gear

Question 3

How is the landing gear constructed and what kind of braking system is it?

Answer 3

Rugged gear

heavy duty braking

Permits operation on a wide variety of ground surfaces

Question 4

POH.4.7.2 Normal Operation

How is the pressure for gear operation furnished?

Answer 4

by an electrically powered, reversible hydraulic pump.

Question 5

How is the pump activated?

Answer 5

by a two-position gear selector switch located to the left of the control quadrant on the instrument panel.

Question 6

How does the gear selector switch work?

Answer 6

wheel-shaped knob, must be pulled out before it is moved to the UP or DOWN position.

When hydraulic pressure is exerted in one direction, the gear is retracted; when it is exerted in the other direction, the gear is extended.

Question 7

How long does it take for the landing gear to extend or retract?

Answer 7

six to seven seconds.

Question 8

What must you exert caution about when the landing gear is in transit?

Answer 8

If the landing gear is in transit, and the hydraulic pump is running, it is NOT advisable to move the gear selector switch to the opposite position before the gear has reached its full travel limit, because a sudden reversal may damage the electric pump.

Question 9

What are the safety features the landing gear system incorporates to insure gear extension in the event of hydraulic failure?

Answer 9

Since the gear is held in the retracted position by hydraulic pressure, should the hydraulic system fail for any reason, gravity will allow the gear to extend.

When the landing gear is retracted, the main wheels retract inboard into the wings and the nose wheel retracts forward into the nose section. Aerodynamic loads and springs assist in gear extension and in locking the gear in the down position.

During gear extension, once the nose gear has started toward the down position, the airstream pushes against it and assists in moving it to the downlocked position. After the gears are down and the downlock hooks engage, springs maintain force on each hook to keep it locked until it is released by hydraulic pressure.

Question 10

What happens when the gear is fully extended or fully retracted and the gear selector is in the corresponding position?

Answer 10

electrical limit switches stop the flow of current to the motor of the hydraulic pump.

Question 11

Why do the three green lights directly above the landing gear selector switch illuminate ?

Answer 11

to indicate that each of the three landing gears is down and locked.

Question 12

How do we confirm the condition of the nose gear?

Answer 12

A convex mirror on the left engine nacelle both serves as a taxiing aid and allows the pilot to visually confirm the condition of the nose gear.

Question 13

What happens if the gear is in neither the full up nor the full down position=

Answer 13

a red warning light on the instrument panel illuminates.

Question 14

What if the throttle is placed in a low setting - as for a landing approach - while gear is retracted?

Answer 14

a warning horn sounds to alert the pilot that the gear is retracted.

The gear warning horn emits a continuous sound on earlier models and a 90 cycles per minute beeping sound on later models.

Question 15

POH.4.7.3 Annunciator Lights

Question 16

If the gear is in neither the full up nor the full down position?

Answer 16

A red warning light on the instrument panel illuminates

Question 17

The three green lights to the left of the landing gear selector switch illuminate….

Answer 17

to indicate that each of the three-landing gear is down and locked.

Question 18

If one or two of the three green lights do not illuminate when the gear down position has been selected:

Answer 18

any of the following conditions could exist for each light that is out:

The gear is not locked down.
A bulb is burned out.
There is a malfunction in the indicating system.

Question 19

How do we check the bulbs?

Answer 19

the square indicator lights can be pulled out and interchanged.

Question 20

POH.4.7.4 Warning Horn

Question 21

Should the throttle be placed in a low setting- as for a landing approach while the gear is retracted,

Answer 21

a warning horn sounds to alert the pilot that the gear is retracted

Question 22

A micro switch incorporated in the throttle quadrant activates the gear warning horn under the following conditions:

Answer 22

1. The gear is not locked down and the manifold pressure has fallen below 14 inches on either one or both engines.
2. The gear selector switch is in the UP position when the airplane is on the ground.

Question 23

POH.4.7.5 Safety Switch

Question 24

To prevent inadvertent gear retraction should the gear selector switch be placed in the UP position when the airplane is on the ground,

Answer 24

a squat switch located on the left main gear will prevent the hydraulic pump from actuating if the master switch is turned on.

Question 25

What do we do during the pre-flight check concerning the landing gear selector?

Answer 25

During the preflight check, be sure the landing gear selector is in the DOWN position and that the three green gear indicator lights are illuminated. On takeoff, the gear should be retracted before an airspeed of 108 KTS is exceeded. The landing gear may be lowered at any speed up to 130 KTS.

Question 26

POH.4.7.6 Emergency Extension

Question 27

To extend and lock the gears in the event of hydraulic failure,

Answer 27

it is necessary only to relieve the hydraulic pressure.

Question 28

What’s the maximum speed of emergency gear extension?

Answer 28

85 Kts

Emergency gear extension must not be attempted at airspeeds in excess of 85 KIAS

Question 29

How do we use the emergency gear extension knob?

Answer 29

An emergency gear extension knob, located directly beneath the gear selector switch is provided for this purpose.

Pulling this knob releases the hydraulic pressure holding the gear in the up position and allows the gear to fall free.

During normal operation, this knob is covered by a guard to prevent inadvertent extension of the gear.

Question 30

What do we do before pulling the emergency gear extension knob?

Answer 30

Place the landing gear selector switch in the “DOWN” position to prevent the pump from trying to raise the gear.

If the emergency gear knob has been pulled out to lower the gear by gravity, it may be pushed in again after the landing is completed and the source of the problem is corrected. Be sure that the landing gear selector switch is in the “DOWN” position before the knob is pushed in.

Question 31

POH.4.7.7 Ground Operation

Question 32

What’s the arc of the nose gear?

Answer 32

The nose gear is steerable through a 27-degree arc either side of center by use of a combination of full rudder pedal travel and brakes.

Question 33

What does prevent shummy tendencies?

Answer 33

A gear centering spring, incorporated in the nose gear steering system, prevents shimmy tendencies.

Question 34

What is the bungee assembly?

Answer 34

Reduces ground steering effort and dampens shocks and bumps during taxiing.

Question 35

What happens when the gear is retracted?

Answer 35

When the gear is retracted, the nose Wheel centers as it enters the wheel well, and the steering linkage disengages to reduce pedal loads in flight. The landing light turns off automatically when the gear is retracted.

Question 36

POH.4.7.8 Tires

Question 37

What’s the dimension of the wheels and its ply rate?

Answer 37

All three-landing gear carry 6.00 x 6 tires.

The nose wheel has a 6-ply tire
and the main wheels have 8-ply tires.

Question 38

POH.4.7.9 Brake System

POH.4.7.9.1 Normal Operation

Question 39

How’s the brake assembly?

Answer 39

Two single-disc, double puck brake assemblies, one on each main gear, are actuated by toe brake pedals mounted on both the pilot’s and the copilot’s rudder pedals or by a hand-operated brake lever located below and behind the left center of the instrument panel.

A brake system hydraulic reservoir, independent of the landing gear hydraulic reservoir, is located behind a panel in the rear top of the nose baggage compartment. Brake fluid should be maintained at the level marked on the reservoir.

Question 40

POH.4.7.9.2 Parking Brake

Question 41

Where is parking knob situated?

Answer 41

The parking brake knob is located on the lower left instrument panel.

Question 42

How is the parking brake set?

Answer 42

To set the parking brake, first depress and hold the toe brake pedals and then pull out the parking brake knob. To release the parking brake, first depress and hold the toe brake pedals and then push in on the parking brake knob.