Gear/Brakes

Question 1

What type of brakes are installed on the Global 7500?

Answer 1

Carbon Disks (4 per wheel).

Question 2

How are the wheel brakes powered and actuated?

Answer 2

Electrohydraulic Brake-by-Wire Control System.

Question 3

How is Weight-on-Wheels sensing accomplished?

Answer 3

Via 6 proximity sensors total, 2 sensors mounted on each gear.

Question 4

How is Normal Extension and Retraction of the Landing Gear controlled?

Answer 4

Electrically controlled by the LGSCU (Landing Gear & Steering Control Unit).

Question 5

What should the Brake Accumulators pre-charge pressure be when the Hydraulic System is Depressurized?

Answer 5

650psi +/- 100psi.

Question 6

Which Hydraulic Systems operate the Landing Gear?

Answer 6

• Hydraulic System 2: Nose Landing Gear + NWS.
• Hydraulic System 3: Main Landing Gear Extension & Retraction.

Question 7

How is excessive Air Pressure due to Heat built-up in the main wheel/tire assembly released?

Answer 7

4 Heat-Sensitive Fuse Plugs on each MLG wheel.

Question 8

How is a Main Landing Gear Overheat condition detected in the Gear bays?

Answer 8

Single Loop Heat sensing elements.

Question 9

How are the MLG doors and NLG doors operated?

Answer 9

• MLG Outboard doors and NLG aft door are attached to the gear;
• MLG Inboard doors and NLG Forward are operated by Hydraulic System 2.

Question 10

How are the Gear Doors opened for Gear Bay inspection on the ground?

Answer 10

• Pull the LG Manual Release Handle in the flight compartment;
• Note: Pins & collars are available to secure the doors.

Question 11

How are the Gear Doors closed after the Gear Bays have been inspected on the ground?

Answer 11

• The LG Manual Release Handle is returned to the Normal Position;
• Hydraulic System 2 pressure is applied;
• The Main Gear Inboard doors will close immediately;
• The Nose Gear Forward doors are closed with a pushbutton on the Forward External Service Panel.

Question 12

What is the Maximum operating Altitude with Landing Gear Extended?

Answer 12

20,000 ft.

Question 13

What is the Maximum Speed for Landing Gear Operation and Extended?

Answer 13

• VLO = 200 Kt.
• VLE = 250 Kt.

Question 14

When is the “TOO LOW, GEAR” aural Warning sound?

Answer 14

• 1. Any Landing Gear is Not down and locked, and
• 2. Radio Altimeters are Less than 500 ft AGL, and
• 3. Speed Less than 190 Kt.

Question 15

When is the Gear aural mutable?

Answer 15

• 1. Any Gear is Not down and locked, and
• 2. Aircraft Altitude below 16,500 ft, and
• 3. Radio Altimeters below 600ft or invalid, and
• 4. Both TLA (Thrust Lever Angle) are below 25° set to Approach, and
• 5. Aircraft speed below 190 kts.

Question 16

What happens when the LG Manual Release Handle is pulled?

Answer 16

• 1. Shutoff and Dump Valves are mechanically actuated;
• 2. Uplocks for all MLG and NG and their doors are Released;
• 3. Alternate Power Valve is mechanically actuated to pressurize the down side of the MLG Retraction
     Actuators to assist free fall.

Question 17

After a Manual Landing Gear Extension, which Caution CAS messages are displayed?

Answer 17

• L MAIN GEAR DOOR;
• R MAIN GEAR DOOR;
• NOSE GEAR DOOR.

Question 18

How will the NWS operate after Manual Gear Extension?

Answer 18

Free-Caster Mode.

Question 19

How is the NWS System normally controlled and actuated?

Answer 19

• Electrically controlled by the LGSCU;
• Hydraulically actuated by Hydraulic System 2.

Question 20

What are the NWS Limits for the Tiller and Rudder?

Answer 20

• Tiller: +/- 82.5°
• Rudder: +/- 9°

Question 21

What is the recommended procedure regarding the Nose Gear before Towing Operations?

Answer 21

• FCOM1 / Chapter 11 / Airplane Servicing / 07.Towing, 01.General.
• Disconnect the Nosewheel Steering Torque Links;
• Ensure minimum of 5,000 lbs is loaded in the tanks or the load on the Nose Gear is not less than 1,900 lbs;
• The CG envelope is within limits.

Question 22

How are the brake wear indicator pins normally checked?

Answer 22

Parking brake or Pedal brake applied with Hydraulic System 2 & 3 pressurized.

Question 23

Which Brakes are operated from the PARK/EMER Handle?

Answer 23

All 4 Brakes.

Question 24

Which Hydraulic Systems operates the Brakes when using the PARK/EMER Handle?

Answer 24

Hydraulic Systems 2 & 3.

Question 25

Which Hydraulic Systems operate the Normal Brake System?

Answer 25

• Hydraulic System 2: Outboard Brakes;
• Hydraulic System 3: Inboard Brakes.

Question 26

How is the PARK/EMER Brake actuated?

Answer 26

Mechanical Linkages to the parking brake valve.

Question 27

If Autobrake is selected ON, under what conditions will it Disarm?

Answer 27

• 1. AUTOBRAKE Rotary switch selected OFF or RTO;
• 2. Brake Pedal application greater than 20%;
• 3. Failure of the BCS or loss of critical input data to BCU from other airplane systems.

Question 28

Describe the Autobrake Deceleration rate.

Answer 28

• Low: 4ft/sec²;
• Med: 8ft/sec²;
• High: 13ft/sec²;
• RTO: 15ft/sec²

Question 29

Describe the Brake Monitoring System relation Color/Range/Action

Answer 29

• Green : 00 – 08 = No Action Required;
• White : 09 – 23 = See AFM (typically wait 35 min).
• Red : 24 and Above = No Takeoff (maintenance action required).
• Magenta: - - Invalid Data.
  Note: Each unit is equal to an increase of 25°C (starting with 00 = -25°C).
  Whenever the brake is applied heavily (i.e. RTO), wait at least 15 min for the brake temp to peak,
  Then go to the AFM 06-06-5 (Maximum Permissible Quick Turn-around Table).

Question 30

When will the Autobrake RTO function be applied?

Answer 30

• 1. The Autobrake Rotary Switch is selected in RTO;
• 2. RTO will be active when Speed > 60 Kt during takeoff;
• 3. Engine Thrust Levers are at idle or Thrust Reversers are applied.