Fuel

Question 1

176. Describe location and capacity of hopper tanks.

Answer 1

Inside each wing tank, adjacent to centerline rib, is a hopper that holds approximately 1267 pounds of fuel.

Question 2

177. What’s the purpose of ventilation system?

Answer 2

It protects from over and under pressurization by allowing air, fuel vapors, and fuel to move about or flow freely.

Question 3

178. Vent tubes are connected to empty chamber or plenum which is located at wing tip, just outboard of fuel tanks. What’s the capacity of plenum and vent tubes?

Answer 3

They provide for 2% fuel expansion.

Question 4

179. What’s indicated if HIGH LEVEL WARN lights illuminate on refuel panel?

Answer 4

High level sensors are wet and Fuel Quantity Signal Conditioner (FQSC) has closed respective refueling valve.

Question 5

180. What happens when REMOTE FUEL SHUTOFF switch is selected on OHPTS?

Answer 5

Switch label turns green and both pressure fueling shutoff valves close.

Question 6

181. What are the different methods of refueling?

Answer 6

Single point pressure fueling or over-the-wing.

Question 7

182. How is automatic refueling controlled?

Answer 7

From Touch Screen Controller (TSC) or refuel panel located at fueling station.

Question 8

183. How many methods are there for maintaining fuel balance?

Answer 8

Two: by moving fuel from hopper to hopper through intertank valve, or by directing fuel from one hopper to opposite engine using crossflow valve.

Question 9

184. How many boost pumps does GVIII have and where are they located?

Answer 9

There are four (4) identical and interchangeable fuel boost pumps in main wheel wells attached to aft portion of each hopper.

Question 10

185. What’s the purpose of fuel boost pumps?

Answer 10

They deliver fuel to engines and APU at relatively low pressure through various fuel distribution lines and shutoff valves.

Question 11

186. How does fuel flow into hopper?

Answer 11

Through ejector pumps and flapper type check valves.

Question 12

187. How do ejectors operate?

Answer 12

They require only fuel boost pump pressure to operate: they’re low pressure, high volume jet pumps. As long as there’s boost pump pressure, ejector pumps deliver steady flow of fuel into each hopper.

Question 13

188. What happens when crossflow valve is opened?

Answer 13

Boost pump manifolds are joined allowing pressurized fuel from functioning pumps to flow to both engines.

Question 14

190. What happens when intertank valve is opened?

Answer 14

Fuel gravity flows between two hopper tanks allowing the tanks to balance.

Question 15

191. What action does Gulfstream recommend before opening intertank valve?

Answer 15

Establish sideslip (i.e., rudder trim in direction of heavy tank)

Question 16

192. What happens when Fuel Return switch defaults to green Auto on power up?

Answer 16

The system allows heated fuel into tanks when fuel tank temperature is ≤ 0°C. When tank temperatures warm to approximately +10°C, heated fuel stops flowing to the tanks.

Question 17

193. There are several abnormal conditions which inhibit heated fuel return system from operating (e.g., fire handle pulled, low fuel pressure signal, low fuel quantity signal). What types of normal conditions inhibit this system from operating?

Answer 17

Crossflow valve open or engine at high power setting.