Center Tank Pumps Failure and ZFW Limit
Hello. Need some input on the following scenario.
- B 737-300
- ZFW limit 48.3 tons
- Center Tank Fuel 7 tons
- Main Tanks 9 tons total (4.5 either side)
- Takeoff at 60 tons
- Soon after takeoff the center tank pumps stop working.
According to the checklist you may not be able to continue your flight to destination because of not enough fuel. So going to destination is out.
Now if your maintenance base is at a distance which is within your reach but leaves you with 2.5 tons of fuel in your main tanks. Would it be better to land at the departure aerodrome or continue to the maintenance base.
If one continues to the maintenance base how will he calculate not to bust the ZFW limit.
If (hypothetically) flight is continued and main tanks are emptied the weight would be 60 - 9 = 51 tons i.e. 2.7 tons above ZFW limit. Busted!
That means if no fuel in main tanks leads to a situation that exceeds the ZFW limit by 2.7 tons then the ratio that causes a ZFW structural concern
would be achieved at a point where you still have fuel in your main tanks.
Is there a way to calculate how much fuel remaining in the main tanks would ring the bells? or its better to land back.
The checklist only mentions that going to destination might not be possible and does not say anything else. Thank you.