Very Large Fire Fighting Tankers

[Franky]

Not used to doing this, hope the link sticks. These aircraft would have been well used in Qld in recent days..

 

[RooFlyer]

I was a bit surprised when I saw that on the news.

Yes, a big hit of water / fire retardant stuff, but against that:

* Cycle time to B737 capable airport, reload, return would be pretty long

* Need to keep height in hilly or mountainous terrain would limit effectiveness in those areas (winds blowing / dispersing the stuff)

* not sure how compatible with people the fire retardant is, limiting application where windy/ close up fire fighters

 

[samh004]

So, the DC10 has a 9k gallon tank (12k gallon according to wikipedia) that takes 15 minutes to refill (wikipedia disputes this to 8 minutes) through 3 hoses... though it is a completely external tank, which seems like a waste of internal space. The guy in the video said the advantage to not modifying the fuselage is it can still pressurise to high altitudes and fight fires all over the world, but also said the facilities onboard do not work.

On the other hand, the 747 (N744ST) has a 19k gallon tank that takes 30 minutes to refill through 2 hoses... and the tanks are internal. The system is not gravity-fed like on the DC10, but is pressurised, perhaps somewhat limiting its capacity. Supposedly the pressure system also needs to be recharged on the ground.

I would have expected the 747 to have a much higher capacity than the DC10, but due to the delivery methods being different I can perhaps see why it doesn't. That said, I see the new 737's have a 4k gallon capacity along with 63 seats for transporting firefighters, so it does seem like the 747 is perhaps a bad use of space.

Does anyone know why they haven't looked into modifying a KC10 or some of the newer air-to-air re-fuelers like the KC46/A330 MRTT into fire tankers? Just thinking about it logically, it would seem the work has already been done on making sure these aircraft are safe to fly and most fires where you look towards tankers helping out end up being funded by the government anyway... they may as well operate the tankers.

I also note that despite being a "global supertanker" it can only operate out of one airport. Sounds a bit like the baseball world series

 

[harvyk]

I also note that despite being a "global supertanker" it can only operate out of one airport. Sounds a bit like the baseball world series

It might take 17 hours to get to the fire front, but when it does.....

 

[Franky]

It might take 17 hours to get to the fire front, but when it does.....

Agree, just like life, there are upsides and downsides to most situations...

 

[Himeno]

I also note that despite being a "global supertanker" it can only operate out of one airport. Sounds a bit like the baseball world series

Where did you get that idea from? N744ST is based at Colorado Springs. It can operate from any airport with a 2,400 m runway.
It has operated out of MCC and SCL, as well as airports in Spain and Israel.

 

[samh004]

Where did you get that idea from?

That video claimed it was only capable of operating from one... I guess they might have meant in California though? There were a fair number of inaccuracies.

 

[trooper]

Does anyone know why they haven't looked into modifying a KC10 or some of the newer air-to-air re-fuelers like the KC46/A330 MRTT into fire tankers? Just thinking about it logically, it would seem the work has already been done on making sure these aircraft are safe to fly and most fires where you look towards tankers helping out end up being funded by the government anyway... they may as well operate the tankers.

I also note that despite being a "global supertanker" it can only operate out of one airport. Sounds a bit like the baseball world series

Not sure how much work it would take to modify a tanker to dump liquid rapidly rather than pumping it (relatively slowly, through relatively small pipes) but I would have thought some sort of portable pallet based system loaded into military cargo aircraft would be a logical method*.... Hell...you could even DROP a series of retardant filled (expendable) bladders with a stabilising drogue..... a variant on LAPES ?? (Low Altitude Parachute Extraction System)

* Yes, there are specialised C130 fire fighting aircraft..I was thinking of something standardised that ANY argo aircraft could carry...they already use standardised cargo pallets...

 

[jb747]

As far as I know, they aren’t retiring KC10s yet. New KC46 or 330 would cost a huge amount...well beyond anything reasonable. And I doubt that they are any more suitable than a second hand airliner.

It’s all a trade off between delivery amount, transit time and turnaround time. I guess they’d have pretty spectacular knock down capability too.

Dropping things doesn’t work unless you’re going to limit yourself to aircraft with rear ramp doors. A bladder within that sort of aircraft would probably be a better bet.

 

[smckay]

I was a bit surprised when I saw that on the news.

Yes, a big hit of water / fire retardant stuff, but against that:

* Cycle time to B737 capable airport, reload, return would be pretty long

* Need to keep height in hilly or mountainous terrain would limit effectiveness in those areas (winds blowing / dispersing the stuff)

* not sure how compatible with people the fire retardant is, limiting application where windy/ close up fire fighters

20 minute load time
Flight time same as commercial plane; LAT and VLAT operate out of Richmond NSW
120 metres is ideal drop height. Hills, mountains, ppffft they just go in and do it
A Cessna spotter is used with smoke trail to guide the big sucker in due to height
Gel is used, does hold the water up. Its not nice to get on you but does wash off. It will re-hydrate when wet so becomes slippery. Last many hours.
Ground crews usually stand aside with phones recording the action. The official advice is lie face down facing plane, cover face and hang on to something solid. Seriously, ground crews know it's coming and stand aside. You don't get any aircraft just pop above you by surprise.

Google a VLAT drop, pretty amazing to have this massive aircraft just above your head and it's not in crash mode.
Here's one I found with the lead plane

 

[jb747]

Certainly nothing to stop you flying a large aircraft down low....

0:14Armée de l'air - French Air Force KC-135 low pass

 

[Captain Halliday]

Certainly nothing to stop you flying a large aircraft down low....

0:14Armée de l'air - French Air Force KC-135 low pass

Yeah, that whole safety thing is over rated.

 

[trooper]

Dropping things doesn’t work unless you’re going to limit yourself to aircraft with rear ramp doors. A bladder within that sort of aircraft would probably be a better bet.

Well..in my defence I WAS talking about military cargo aircraft.... which IME are rear ramp types.... and I did ALSO mention the idea of a palletised system for them...other than the dropped type...

P.S. That's got to be the best low pass ever....so much more impressive than a fighter doing it...