747 Water Tankers

[torrence]

Impressive pix of tanker 747s dropping water on current So Cal fires today on TV.  Without trying to complicate things too much, maybe PSX could include a 'tanker' version where the water drop could be simulated by a very fast decrease in gross wt. ?

Cheers,
Torrence
KLAX

[Hardy Heinlin]

I guess that would be extremely simplified. I'm sure this would also require zillions of modifications in the weight & balance system, EICAS, FMC, electrical etc.

Maybe something for PS11 ... :-)


Cheers,

|-|ardy

[Phil Bunch]

Also need an autopilot mod to handle the sudden, rapid loss of weight as the water cargo is dumped.

Similarly, one needs to be able to (carefully!) drive the 747 along the surface of a lake or ocean to scoop up a fuselage of new water and then take off.

At least this is how a 4-engine propeller tanker did it, on a recent TV documentary show I watched (grins).  It was impressive to watch the pilots fly the thing at low altitude as they dumped their water onto a fire while holding a constant height above the ground/fire.

"Amateur pilots need not apply..."

[Avi]

Similarly, one needs to be able to (carefully!) drive the 747 along the surface of a lake or ocean to scoop up a fuselage of new water and then take off.

Are you sure this is how it done?
Don't they land for "refueling"?

Propeller is one thing, jet (and especially the 747) is a different story.
It can't fly slowly and it should take very long time to refill the tanks (comparing the small aircrafts). This is sound very dangerous to me.

Thanks,

[torrence]

I'll see if I can find some of the information about how these things are flown.  I think I looked into it a couple of years ago.  First I suspect that this is not autopilot territory.  Flights are low, slow, in steep terrain.  TOGA probably used once water is dumped.  Phil - I don't think they fill these by scooping like the smaller craft, but don't know for sure.  It would sure seem dicey to me to fly a 747 just feet above GL, scooping up water.  Whatever, these guys do an unbelievable job.

Cheers,
Torrence

[Shiv Mathur]

http://www.youtube.com/watch?v=GBmZ4AcMb7w&feature=related
http://www.youtube.com/watch?v=Ialg6SSZwTg

Lots of similiar stuff on youtube. The key search words would be
'super scooper'.

[Jeroen Hoppenbrouwers]

I believe there's just one company, Evergreen, who operates these 747 tankers.
http://www.youtube.com/watch?v=uUEqbLVfpGc
You see large water buckets being used to fill the plane with (red) test liquid; I presume this is also more or less how they fill it for fire suppression. Not by scooping. This isn't a fast turnaround option.

If you search on YouTube and related sites for "747 tanker" you get lotsa material, including recent stuff.

I wonder what it'll cost you if you call Evergreen and order a full dump at coordinates X,Y in an hour.


Jeroen

[OKD]

Just going back on a few statements being made previously concerning about the C of G when the water is being dumped.

Isn't the operational procedures are almost the same as "Fuel Balancing" during flights? Of course normal flight would have more time and stability to perform the procedure, but just wondering..

I am just imagining that as the water is being dumped out, the pilot would just release the valves of each water tank in a timely and "balanced" manner...say within 10 seconds flying over the affected area or zone?

Please give me a few cents worth of your knowlege, guys?

thanks

[Jeroen Hoppenbrouwers]

I'm sure there will be a fully automatic dumping system aboard, no pilot operation needed, just push the button. What's inside the plane I have no clue and I am not sure it is even publicly known -- this is a private company, after all. Of course the FAA must have certified the modification, but that does not mean it is public, is it?

I guess the displacement of the C/G must be within strict limits, so that either the pilot or some trim assistant system can guaranteed follow it up. The only good answer would come from the guys operating this plane.

Jeroen

[Hardy Heinlin]

No -400?

No PS :-)

[Jeroen Hoppenbrouwers]

Certainly no -400, but certainly no standard -100, -200, or -300 either. Funny blue bar graph displays very prominently placed, likely tank content (balance!). Likely 747-380   :mrgreen:

[OKD]

That's a good one, JH!!

Or perhaps is something to think about for Hardy's future PX X.1 for year 2013 on a 747-801?

[OKD]

Sorry...PS X.1

[brian747]

No -400?

No PS :-)

Well there seems to be a 744 now. Allegedly...      (Although I'm not sure why in some shots someone has painted "944" on the tail...).   

But the blurbs do seem to think it's a 744:—

"The B747-400 SuperTanker is the true "Next Gen" air tanker.  It joins the worlds fleet of aerial firefighting tankers not only as the youngest VLAT (VERY LARGE AIR TANKER) but with almost twice the capacity of the next largest aerial tanker.  The two separate, but identical constant flow systems are pressurized which allows for either continuous discharge or up to 8 segmented drops.  Coverage levels range from CL2 to CL8 and above.  The system is approved for retardant, gel, foam and water drops or the combination of any two of these agents and ground servicing for another sortie takes approximately 30-35 minutes.

The SuperTanker operates without any speed, altitude or operational restriction and provides a level of safety to ground personnel, property and natural resources unmatched by any other tanker, civilian or military.  The exceptional and superior performance of the SuperTanker is such that it departs 200,000+ pounds below maximum allowable gross weight and can land immediately without dumping fuel or retardant if the operation is cancelled."

"The eight main tanks can carry 74,200l (19,600gal) of water, retardant or oil dispersant. Powered by four General Electric CF6-80-B1F engines, the 747-400 can carry that load over 4,000nm (7,400km) at speeds approaching 520kt (960km/h)."


3D interior display:

https://my.matterport.com/show/?m=aTr7JdsujKk&f=0

Story:

http://www.popularmechanics.com/flight/a22299/747-firefighting-virtual-experience/

Web page (with 8 minute video):

http://globalsupertanker.com/b747-400-supertanker/

Some short videos:

https://vimeo.com/user47808920


So what do you think, Hardy: if this really is a true 744, might there perhaps be a potential option for a "Dispersing Control Station"??     

Cheers,

Brian

[Hardy Heinlin]

Perhaps-maybe-possibly when my todo list gets shorter :-)

Unfortunately it's getting longer and longer every day ...


Cheers,

|-|ardy

[John H Watson]

Don't show this stuff to Chemtrail Conspiracy Theorists 

[Phil Bunch]

Revealing my total ignorance about water pumping and dispersal, I don't see how they could reload this 747 in 30 minutes with the 20,000 gallons mentioned in the article.  I also don't understand how they could dump it in 10 seconds.  Finally, I don't understand how they could safely fly the plane while suddenly losing that much weight!

Perhaps it is just the magic of computers to help fly the plane while dumping, but it must take one heck of a pumping system on theh ground to refill within 30 minutes.  How many gallons per minute does a large fire truck pump?

[G-CIVA]

Revealing my total ignorance about water pumping and dispersal, I don't see how they could reload this 747 in 30 minutes with the 20,000 gallons mentioned in the article.  I also don't understand how they could dump it in 10 seconds.  Finally, I don't understand how they could safely fly the plane while suddenly losing that much weight!

Perhaps it is just the magic of computers to help fly the plane while dumping, but it must take one heck of a pumping system on theh ground to refill within 30 minutes.  How many gallons per minute does a large fire truck pump?

Here is your answer, the actual flight into & over head the target is, as it always has been a manual & visual manoeuvre but the flexibility behind the electronic wizardry is state of the art.  Of course the 747 proves once again how flexible it is.

https://vimeo.com/189948533

[Jeroen Hoppenbrouwers]

US fire engines seem to do 1500 gpm.

http://www.fireapparatusmagazine.com/articles/print/volume-15/issue-8/departments/pump-talk/history-brings-us.html

[John H Watson]

 

I don't see how they could reload this 747 in 30 minutes with the 20,000 gallons mentioned in the article.

20,000 US gallons = 75,000 litres = 75 metric tonnes (water). I guess it depends on how many pumping trucks are hooked up. You can easily pump that much fuel (75,000 litres/60,000 tonnes) with two fuel trucks in 30 minutes.