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Using a 747 to Fight Wildfires
RotJ writes "It's fire season again. And the government just grounded 33 aging air tankers on Monday due to safety issues. Looking for a modern solution, Evergreen Aviation has come up with a 747 supertanker with 24,000 gallons of tank space onboard, which allows it to cover seven times the area of today's largest existing airtanker. In addition to fighting fires, it will be able to contain oil spills and 'perform challenging homeland security missions' like neutralizing chemical or biological attacks. And think of how many John Goodmans you could cover with fire retardant. Be sure to watch the videos."
How will it protect us from a biological attack? By drowning us in more harmful anti-bodies instead?
I'm no aerospace engineer.... But I thought 747's weren't particularly strong. How much does all that water weigh compared with what a 747 could carry?
I've got more mod points and GMail invi
Well, ofcouse, I dont know if the guy is accurate or not.
n s. pdf
But he claims about 170mph for takeoff.
I would see this as a lowest for flying speed at low altitude.
But that's still pretty damn fast
http://pupgg.princeton.edu/~phys103/quiz97/q7_a
Cost - even the smaller water bomber's are expensive. Operating cost of a 747 would be even higher again.
Accessability - a 747 doesn't operate from small dirt airfields or remote areas. I can see one of these trying to fly from a larger area to a remote area to drop water. (See costs)
Speed - they'd be running a lot faster than most water bombers. I can here the STALL STALL warnings now.
Accuracy - See Speed.
They might be good for fast burning "California or OZ" fires but I not sure they would be much use for most medium size forest fires. IMHO
Interesting is that it covers "7 times" of what a normal air tank covers. As amateur I would assume that it takes similar time to cover the burning area, it just takes makes re-fitting faster. It is probably harder to fly as whell.
Beside that the chemical and biological "homeland" security aspect is ridiculous. You dont have such planes equipped in time fight such attacks.
Some people might get a little wet... and appropriately ticked off; but, it's better to get suddenly drenched than to have a 747 crash land on your head.
Oh I think that water would probably hurt pretty good when it reached the ground. Sure it would probably be less messy than the plane crashing but you would definitely have some casualties. Go stand at the bottom of the Empire State Building while I dump a swimming pool worth of water on you.
Exactly, and I would rather have a C130 do that work instead of a 747. Hercules can fly half as fast as those big commercial jets when needed. One even landed on a carrier.
Maybe we deserve this world ?
They could also use baffles to keep the water from sloshing around.
When I was in high school, I routinely hauled water to cattle in an old truck with a thousand gallon water tank.
The only time that it got dicey was if I used part of the water in one location and the rest in another.
With the tank half empty, the sloshing was unbelievable. If you weren't careful, it was entirely possible to turn the truck over.
Sure, if it all came out in one big lump. That's not how they're designed, though. They'll dump using the sprayers, so yeah, you'll get soaked if you're in the path, but it beats 100 tons of water all at once.
Drop tanks, now, are another story.
Besides all the discussions about flying a 747 at very low speed and about the manouvrability at low altitude, what happens to the plane when in a few seconds it becomes 100 tons lighter? Don't know the ratio between the empty and full weight of the plane, but loosing weight that fast doesn't seem to be a situation when I would like to be a pilot. And definitely not one when you are low speed, low altitude.
Browsers shouldn't have a back button!! It's all about going forward...
I might also agree with you if I knew the details of these:
1. How much does the maintance of a 747 cost? During operation and non operation (fuel, repairs, metal fatique, parts)
2. How much would the maintance cost of a smaller plane? My guess is that it would be cheaper.
3. If smaller planes maintance is cheaper then a 747 then maybe you can get a fleet of smaller planes compared to one big one.
4. Are 747's ok to use in all terain types?
-- I don't buy it, I grow it.
Rather than cutting them up, why not cut a deal with the Russians and keep a few B52H bombers in water tanker service? With the appropriate firefighting gear in the bomb bay, it would be difficult if not impossible to revert back to a bomber; heck, give the Russians the contract for the firefighting mods.
After all, the BUFF has a proven track record of being stressed properly for low-altitude flight; there are plenty of retired USAF pilots and navigators out there who have 1000+ Time-in-Type, as well as mechanics, spare parts, etc.
...-.-
Try this gedanken experiment: Fill a bucket about half full of water. Now grab the bucket with both hands and run down the street. Once you get up to speed, try to stop or turn quickly without spilling any water. In fact, try to do it without letting the weight shift inside the bucket.
You see, as soon as you try to quickly change speed or direction, the weight shifts. When 24,000 gallons of water shifts, you have a lead sinker on your hands.
Watch the videos of those planes crashing. That is exactly what it looks like happened. The pilot tried to pull up, but the water shifted, and the plane lost it's wings under the intense weight shift.
This reminds me of a friend in highschool who's dream car was a hearse with a waterbed in the back. Sounds like a good idea untill you try to turn a corner at any speed greather than 5 mph!
By the way, Shane, if you are reading this, contact me.
At least a military aircraft would be designed for the maneuvers required to fight forest fires.
But really, these machines are VAST, and are turbojets the right engines for low-altitude use? I don't think so. You want an engine optimized for close-to-the-ground operation, that will spool up quickly so you have power when you need it.
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