Water in fuel-good catch by SW personnel

[pelmet]

A good reminder on a possible indication of fuel contamination...

"C-FYJD, a Boeing 737-800 aircraft operated by Sunwing Airlines, was conducting flight SWG737 from Montego Bay/Sangster Intl, Jamaica (MKJS) to Calgary Intl, AB (CYYC). After the refueling procedure was completed during the pre-departure set up, the flight crew noticed an abnormal behavior of the fuel gauges. The operator’s Maintenance Control Centre (MCC) was consulted and
instructed the flight crew to have the fuel verified for contamination. The sample revealed that the fuel was contaminated with water by more than 30%. The passengers were deplaned and maintenance personnel proceeded to drain all water from the reservoirs. The flight subsequently departed and reached its destination without further event.

[fish4life]

Good catch but it is disturbing on something the size of a 37 how many hundreds of gallons of water got in there.

[atphat]

Very good catch by the crew. That's an incredible amount of water. Very scary indeed.

[5x5]

Kind of curious - what kind of abnormal behaviour would fuel gauges exhibit to indicate the presence of water?

[kilpicki]

Must me a short version of the story. If water is in fuel it can't be drained out with the sumps as it would take hours to settle out.

[av8ts]

.

[GyvAir]

Must me a short version of the story. If water is in fuel it can't be drained out with the sumps as it would take hours to settle out.

Agreed.. something doesn't add up. If it was 30% suspended, that would require more than a quick sump draining, for sure.

Kind of curious - what kind of abnormal behaviour would fuel gauges exhibit to indicate the presence of water?

When water coalesces in the capacitors (fuel quantity probes) it affects the readings. Suspended water in large quantities presumably would change the dielectric properties of the fuel as well, thus giving unexpected readings.

Good catch but it is disturbing on something the size of a 37 how many hundreds of gallons of water got in there.

from Montego Bay/Sangster Intl, Jamaica

Sometimes perceptions are different as to safe fuel handling practices in less developed countries. Fuel truck/water truck... Potato/potahto.

[cgzro]

Yes the fuel guages if they use two depthwise parallel rods separated by fuel or air operate by measuring the charge between the rods. Air creates one ability to store charge and fuel another. By comparing all air to all fuel you get a level indication of empty and full. Water has different properties when it separates the two rods and the charge stored will be different. As a result the final reading will be much higher (or much lower, cant remember).

No doubt they were surprised that either all the readings were too low or the guage is designed to flag when it reads over full.

[kilpicki]

Not sure about Jamaica but in other less developed places (some African countries) aviation fuel is heavily guarded as it is used for cooking etc. Back in the day it was not uncommon to find the fuel replaced with water. In the bowzer and in the aircraft.

[Heliian]

Probably from heavy rain or a bad valve selection. Usually, the airport fueling system would have protections to avoid such an ingress of water, who knows, maybe they left the fuel cap open on the overwing.

They are more than capable in Montego bay and have many aircraft through each day. Someone made an error somewhere, glad they fixed it.

[BMLtech]

Had a similar incident many years ago with a 727 freighter that picked up a load of fuel in YXX that turned out to be heavily contaminated with water. All fuel qty gauges malfunctioned. Required complete defueling /scrapping of fuel, and removal of fuel probes to be cleaned in alcohol. Jet fuel is somewhat hydroscopic and heavy water contamination will result in water entrained in the fuel that can't be removed by sumping.

[co-joe]

Not sure about Jamaica but in other less developed places (some African countries) aviation fuel is heavily guarded as it is used for cooking etc. Back in the day it was not uncommon to find the fuel replaced with water. In the bowzer and in the aircraft.

Just like dad's liquor bottles in high school.