View Full Version : EverGreen 747 Water Drop movie
This was found on www.airtanker.com and I thought you all would get a kick out of it:
www.everzone.org/down/highaltitudedrop.wmv
Yeah sure it was awesome !
Never seen a photo of a 747 doing tha job.
Only question is, why at such a high altitude ?????
Any guesses ?
YA
Joles:D
No comment
9th Apr 2004, 20:29
Think the drop was at high altitude because the 747 was in the process of being certified as a water bomber.
Better to do it at high altitude as the weight and balance changes dramatically when the water/retardant is dropped - you've got a bit more air to play with!
Notso Fantastic
9th Apr 2004, 20:53
I'm surprised it is thought to be effective. Loading time must be considerable. The 747 is not a beast to be landed quickly, or departed quickly with the potential for massive trim problems. Frequency over target would not be very high. Now that Russian Beriev flying boat, loading up by skimming over a lake or in a high speed run in the water, then lifting off would be back over target far more rapidly (if there was a lake!) with a good load.
PAXboy
10th Apr 2004, 12:19
This topic was running in a different thread last week. IIRC, the conversion is setting up multiple container tanks for faster loading and selected drop. i.e. you might have some with retardant and some with water and can release part load on each pass.
The conversion also plans to keep the a/c within it's original design parameters. This means dropping at a higher altitude (obviously not as high as in the test) and so the tanks are pressurised to make the drop more focused and this appears to be the case with the test shown in the movie. You can see a jet directing downwards.
They hope that the capacity of the a/c, dropping sequentially in two (or more) passes, will offset the limiting factors of loading. But I sit to be corrected on all of the above.
Why do this? Hey, what else are they gonna do with all those '47s when the 380 takes over ... :E
sidman
10th Apr 2004, 22:26
I know the crew that is doing the test flying and was told that there are no real trim problems... The film clip is just a normal drop no pressure.. They are now at low level pressure drops and things are still going well.