747-400 Liquid from Tail?
Jun 18, 2016, 11:14 am
#1
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Join Date: Dec 2010
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747-400 Liquid from Tail?
Moments ago I watched what I believe was UA838 (NRT->SFO) a 747-400 at ~6,200 ft directly overhead (per flightradar24) on approach to SFO. From the tail, was streaming some sort of liquid. It was not a contrail.
Any ideas what this was?
Any ideas what this was?
Jun 18, 2016, 4:03 pm
#3
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Initially I thought it might have been fuel dump for an emergency landing, but upon determining the flight was likely NRT->SFO (and not something that had just taken off) thought unlikely the plane would be overweight. Further, I believe dump is from the wings, not the tail.
Jun 18, 2016, 4:27 pm
#5
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Jun 18, 2016, 4:37 pm
#6
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Initially I thought it might have been fuel dump for an emergency landing, but upon determining the flight was likely NRT->SFO (and not something that had just taken off) thought unlikely the plane would be overweight. Further, I believe dump is from the wings, not the tail.
Jun 18, 2016, 5:35 pm
#7
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I'm curious how at over a mile vertical distance (plus any addl X/Y distance) you could see liquid dripping, especially if it took well under a second to disapate.
Jun 18, 2016, 6:00 pm
#8
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Jun 18, 2016, 6:01 pm
#9
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I too am curious about what you saw.
It's just hard to imagine how, if it was not a cloud of vapor, a real liquid stream would be visible that far away -- and moreover, how a plane could be putting out so much liquid to make it visible that far away? If only we could have a picture or a picture similar to what you were seeing? One stream, you say?
Is it possible that a reflection or refraction of the sun at a certain angle into a vapor trail made it look like liquid?
It's just hard to imagine how, if it was not a cloud of vapor, a real liquid stream would be visible that far away -- and moreover, how a plane could be putting out so much liquid to make it visible that far away? If only we could have a picture or a picture similar to what you were seeing? One stream, you say?
Is it possible that a reflection or refraction of the sun at a certain angle into a vapor trail made it look like liquid?
Jun 18, 2016, 6:18 pm
#10
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Join Date: Dec 2010
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I too am curious about what you saw.
It's just hard to imagine how, if it was not a cloud of vapor, a real liquid stream would be visible that far away -- and moreover, how a plane could be putting out so much liquid to make it visible that far away? If only we could have a picture or a picture similar to what you were seeing? One stream, you say?
Is it possible that a reflection or refraction of the sun at a certain angle into a vapor trail made it look like liquid?
It's just hard to imagine how, if it was not a cloud of vapor, a real liquid stream would be visible that far away -- and moreover, how a plane could be putting out so much liquid to make it visible that far away? If only we could have a picture or a picture similar to what you were seeing? One stream, you say?
Is it possible that a reflection or refraction of the sun at a certain angle into a vapor trail made it look like liquid?
Jun 18, 2016, 6:36 pm
#12
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I'm further south on 280 near Sand Hill / Alpine. Hawaii flights start the turn directly overhead, Asia slightly earlier and Pac NW earlier still. 789 from HND just passed straight up (x/y=0) @ 6,200 ft (net 6,000 ft).
Jun 19, 2016, 12:31 am
#14
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