Post by CoolP on Mar 20th, 2011 at 12:00pm
Thanks for answering, Pete.
I'm running onto two problems when talking about the current fuel dump procedure.
First, I think that the Center Tank has to be the first one to get emptied, just because it's the last one to be filled. Later on, the 2&3 mains have to follow, until they've reached a certain level where their fuel equals the amount of the outer 1&4 + Reserve.
That's the schedule you have to follow when just burning fuel on the 707. Why alter it when dumping?
Second, the unequal dumping produces large imbalances. Look at the gauges. If Tank 1 goes empty while Tank 4 stays full (this currently happens), you'll get 15.000 lbs of imbalance.
Later, when Tank 2 goes down and Tank 3 stays full, you'll earn 27.000 lbs. That's over 12 tons!
Also, since the plane is meant to feed its engines from Tanks 1,2,3,4 (=Mains) until the end of the flight, this dumping might lead to starving engines, because the current process gives you a full Center Tank but empty mains and wings.
Here are some docs where the fuel setup for burning fuel and also for filling your tanks is described. All of them show the importance of no imbalance and also the one of the main tanks, which are 1-4.
Still convinced that the fuel dump works as intended? :)
I'm running onto two problems when talking about the current fuel dump procedure.
First, I think that the Center Tank has to be the first one to get emptied, just because it's the last one to be filled. Later on, the 2&3 mains have to follow, until they've reached a certain level where their fuel equals the amount of the outer 1&4 + Reserve.
That's the schedule you have to follow when just burning fuel on the 707. Why alter it when dumping?
Second, the unequal dumping produces large imbalances. Look at the gauges. If Tank 1 goes empty while Tank 4 stays full (this currently happens), you'll get 15.000 lbs of imbalance.
Later, when Tank 2 goes down and Tank 3 stays full, you'll earn 27.000 lbs. That's over 12 tons!
Also, since the plane is meant to feed its engines from Tanks 1,2,3,4 (=Mains) until the end of the flight, this dumping might lead to starving engines, because the current process gives you a full Center Tank but empty mains and wings.
Here are some docs where the fuel setup for burning fuel and also for filling your tanks is described. All of them show the importance of no imbalance and also the one of the main tanks, which are 1-4.
Still convinced that the fuel dump works as intended? :)