jsoceanlord
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747 fire bomber
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Two large aircraft are under development for that purpose right now; the B747, and the DC-10.
The real problem lies in that such a platform has some limited application on large project fires, but not on tactical missions or early starts. Additionally, the facilities from which these aircraft can operate is limited, as their application in the fire environment.
The concept of the "supertanker" has been bantied about for years. What's not considered is that just like the caliber of a weapon, it's not the size, it's how you use it.
Firefighting isn't about dumping all the water or retardant you can on a fire. That can serve to make things worse, if it's not done properly.
Firefighting is seldom done on a nice, flat plain in calm conditions. In fact, from an aerial attack standpoint, it's never done. It's generally done in very hilly or mountainous terrain in very low visibility in high winds, often with severe to extreme turbulence. The aircraft involved often must make tight turns, or have the capability of doing so. Drop altitude is within a narrow range; too close and damage can occur to the surface (including pushing the fire, shadowing in which only part of the fuel is covered, risk to personnel on the ground, etc). Too high and there is excessive drift, the inability to target or build line, and the likelihood of dissipation and ineffectiveness of the drop.
An aircraft dropping the volume described for the B747, as put out by Evergreen, will need a minimum drop height of 800' or higher, making controllability of the retardant or water/wet-water very difficult. It may have value in generally cooling a large flame front, but those who have been in a real fire, with 300' flames and temperatures in excess of 2,500 degrees, know that there's nothing mankind can do to really cool that kind of a fire. Direct attack is not the answer.
The 747 in close quarters in rough air at slow airspeeds (necessitated for proper use of retardant) in near zero visibility may present a number of problems, both due to maneuverability, the swept wing, the turbofan engines over a fire, the quantity of drop material, etc.
The turbofan engines must also be considered; during the last spat of fires in Southern California, six tankers had their windscreens shattered on the first day, by flying trees and debris. Try fodding out the engine on the airliner you fly with a tree, and see what happens. Think of it this way; if you ingest a large object in your airplanes engines, are you going to return and load, and come back again without a very thorough maintenance check and release? On a fire, speed is time is life, and there isn't time to down the aircraft because you hit something...if that's going to be an issue, don't go to the fire in the first place.
Dispatch locations are an issue. While the 747 has a high cruise speed in the flight levels, it would be operating at lower levels most of the time; slower speeds, high fuel consumption. The number of tanker bases that can accomodate an aircraft at that weight are few and far between; the tanker would need to ferry a very long distance, adding to long turn around times and increased costs. Much better to have several single engine air tankers or even P2V's and DC-4's nearby to hit the fire repeatedly in a shorter time, for less money.
The ability to operate the airplane would be very limited due to facilities, and a host of other factors. I'm not saying it's not a good idea, but it's certainly not the panacea that one might think. If it is viable, it will be one more tool to be used over the fire, albeit a very limited tool with few applications.
The real problem lies in that such a platform has some limited application on large project fires, but not on tactical missions or early starts. Additionally, the facilities from which these aircraft can operate is limited, as their application in the fire environment.
The concept of the "supertanker" has been bantied about for years. What's not considered is that just like the caliber of a weapon, it's not the size, it's how you use it.
Firefighting isn't about dumping all the water or retardant you can on a fire. That can serve to make things worse, if it's not done properly.
Firefighting is seldom done on a nice, flat plain in calm conditions. In fact, from an aerial attack standpoint, it's never done. It's generally done in very hilly or mountainous terrain in very low visibility in high winds, often with severe to extreme turbulence. The aircraft involved often must make tight turns, or have the capability of doing so. Drop altitude is within a narrow range; too close and damage can occur to the surface (including pushing the fire, shadowing in which only part of the fuel is covered, risk to personnel on the ground, etc). Too high and there is excessive drift, the inability to target or build line, and the likelihood of dissipation and ineffectiveness of the drop.
An aircraft dropping the volume described for the B747, as put out by Evergreen, will need a minimum drop height of 800' or higher, making controllability of the retardant or water/wet-water very difficult. It may have value in generally cooling a large flame front, but those who have been in a real fire, with 300' flames and temperatures in excess of 2,500 degrees, know that there's nothing mankind can do to really cool that kind of a fire. Direct attack is not the answer.
The 747 in close quarters in rough air at slow airspeeds (necessitated for proper use of retardant) in near zero visibility may present a number of problems, both due to maneuverability, the swept wing, the turbofan engines over a fire, the quantity of drop material, etc.
The turbofan engines must also be considered; during the last spat of fires in Southern California, six tankers had their windscreens shattered on the first day, by flying trees and debris. Try fodding out the engine on the airliner you fly with a tree, and see what happens. Think of it this way; if you ingest a large object in your airplanes engines, are you going to return and load, and come back again without a very thorough maintenance check and release? On a fire, speed is time is life, and there isn't time to down the aircraft because you hit something...if that's going to be an issue, don't go to the fire in the first place.
Dispatch locations are an issue. While the 747 has a high cruise speed in the flight levels, it would be operating at lower levels most of the time; slower speeds, high fuel consumption. The number of tanker bases that can accomodate an aircraft at that weight are few and far between; the tanker would need to ferry a very long distance, adding to long turn around times and increased costs. Much better to have several single engine air tankers or even P2V's and DC-4's nearby to hit the fire repeatedly in a shorter time, for less money.
The ability to operate the airplane would be very limited due to facilities, and a host of other factors. I'm not saying it's not a good idea, but it's certainly not the panacea that one might think. If it is viable, it will be one more tool to be used over the fire, albeit a very limited tool with few applications.
furloughfodder
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http://www.evergreenaviation.com/supertanker/index.html
Check out the Promo Video.
I have seen it in operation on the ground during testing. VERY impressive.
Check out the Promo Video.
I have seen it in operation on the ground during testing. VERY impressive.
Last edited:
furloughfodder
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2000flyer
EASY FLYER
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Take a look at the bottom left picture. Looks an awful lot like the World Trade Centers to me. I hope I'm wrong, but if not, that has to be the tackiest ad I've seen.
http://www.evergreenaviation.com/supertanker/images/montage_2.jpg
http://www.evergreenaviation.com/supertanker/images/montage_2.jpg
You're right, it does appear to be the WTC. Those are artists renderings, but in each case the drop would be completely ineffective (to say nothing of the inappropriate suggestion that the tanked 747 would have any effect on the WTC events or subsequent fires).
As for the other pictures...water on the burning oil tanker...aaah, did anyone consult a firefighter before drumming that one up? Anybody ever throw water on a grease fire??
The retardant drop some half mile or more away from the fire line, with what appears to be better than fifteen hudred feet of altitude is impressive. Wasteful, but impressive. In fact, all the pictures look rather silly.
I hope they succeed, I really do. I had hopes that the A-10 program might make some headway...but until something better comes along than the way we do it now...those concepts may not be as viable as the excitement they generate.
As for the other pictures...water on the burning oil tanker...aaah, did anyone consult a firefighter before drumming that one up? Anybody ever throw water on a grease fire??
The retardant drop some half mile or more away from the fire line, with what appears to be better than fifteen hudred feet of altitude is impressive. Wasteful, but impressive. In fact, all the pictures look rather silly.
I hope they succeed, I really do. I had hopes that the A-10 program might make some headway...but until something better comes along than the way we do it now...those concepts may not be as viable as the excitement they generate.
VNugget
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DC4boy
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Hey Avbug, through the rumor mill I've heard they're gonna try a drop speed (cringe) of 120 KIAS and the idea of mixing mud in flight.
Nobody's ever mentioned the de-mob of the fire thats going to be nessasary for this thing to drop.
Can the structure of this aircraft handle loosing an engine on take off and dropping the whole load at once?
I've heard that they're only going to run fuel in the center section fuel tank.
Nobody's ever mentioned the de-mob of the fire thats going to be nessasary for this thing to drop.
Can the structure of this aircraft handle loosing an engine on take off and dropping the whole load at once?
I've heard that they're only going to run fuel in the center section fuel tank.
Only time will tell. I find it hard to believe that they'll have adequate controllability in a 3,000 fpm downdraft behind a ridge at 120 KIAS and gross, with rotors that exceed anything put out by a heavy aircraft on final...but what do I know?
As for dropping compartmentalized loads such as with the balloon concept, it may have merit, but I can only imagine the liability of one ever contacted a person, house, whatever.
Such concepts have been tried before, long ago. Many ideas have been tried, from retardant bombs made of drop tanks, to large droptanks full of retardant, with glass ends that are detonated with explosive squibs.
In my opinion, the miriad systems presently in use are hard to improve on.
The PB4Y-2 was the only tanker built which ever conformed to the drop standard and met the requirements of all the tests, anyway.
As for dropping compartmentalized loads such as with the balloon concept, it may have merit, but I can only imagine the liability of one ever contacted a person, house, whatever.
Such concepts have been tried before, long ago. Many ideas have been tried, from retardant bombs made of drop tanks, to large droptanks full of retardant, with glass ends that are detonated with explosive squibs.
In my opinion, the miriad systems presently in use are hard to improve on.
The PB4Y-2 was the only tanker built which ever conformed to the drop standard and met the requirements of all the tests, anyway.
furloughfodder
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"At no time in flight will the Evergreen Supertanker operate outside the Boeing 747’s normal operating parameters. The drop speed is approximately 140 knots. This provides a 30% cushion over the Boeing 747’s stall speed."
That was a quote from the website. They won't be operating at 120 kts.
So what are some other suggestions for fighting massive forest fires? The last 2 years have been devastating, and the present method of combating these blazes doesn’t seem to be working. From the previous posts you sound pessimistic about the chances of this succeeding.
That was a quote from the website. They won't be operating at 120 kts.
So what are some other suggestions for fighting massive forest fires? The last 2 years have been devastating, and the present method of combating these blazes doesn’t seem to be working. From the previous posts you sound pessimistic about the chances of this succeeding.
flyingwildfires
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It has to be able to get to the fire
Avbug is right, fires never burn on nice flat spreads that look like Kansas. It can be hard as h*ll to get down near the fireline in rugged terrain, and sometimes impossible. I've been on fires (on the ground) where we begged the tankers NOT to drop, as it was so frigging steep it would have blasted the fire all over the side of the mountain, instead of just the 200' duffy square we had. The advantage I would see for a massive tanker like this would be in open country, with relatively easy drops, in lighter fuels. Bigger is not always better... accuracy beats volume any day. As for the mega-water-balloon concept, that's where aerial delivery all got started way back when, if my memory serves me. It's not too good at all. Any drop has the potential to injure ground personnel, hence drop heights that need to be high enough to allow the retardant to "mist" and then rain down to coat the fuels, yet low enough to not drift away in turbulent air. It's a lot more complicated than just buzzing by in a roar and trying to hit something with luck... these pilots are good, and are working for the ground pukes. I know I was always happy as h*ll to hear 'em coming.... that rumble of round engines can be heard a long ways in the mountains.. some of my best memories...
Avbug is right, fires never burn on nice flat spreads that look like Kansas. It can be hard as h*ll to get down near the fireline in rugged terrain, and sometimes impossible. I've been on fires (on the ground) where we begged the tankers NOT to drop, as it was so frigging steep it would have blasted the fire all over the side of the mountain, instead of just the 200' duffy square we had. The advantage I would see for a massive tanker like this would be in open country, with relatively easy drops, in lighter fuels. Bigger is not always better... accuracy beats volume any day. As for the mega-water-balloon concept, that's where aerial delivery all got started way back when, if my memory serves me. It's not too good at all. Any drop has the potential to injure ground personnel, hence drop heights that need to be high enough to allow the retardant to "mist" and then rain down to coat the fuels, yet low enough to not drift away in turbulent air. It's a lot more complicated than just buzzing by in a roar and trying to hit something with luck... these pilots are good, and are working for the ground pukes. I know I was always happy as h*ll to hear 'em coming.... that rumble of round engines can be heard a long ways in the mountains.. some of my best memories...
If you believe I'm being pessimistic by seeing this as anything other than a very limited-option tool, then yes, I am.
With regard to "devastating fires," one should note that most of the serious fires we've had have been man-made. First line of defense, stop lighting forest fires.
Second, anybody who has ever fought fire, especially wildland fire, comprehends in a way that cannot be explained that a fire can be well beyond anything mankind can field to put it out. Nothing we have, including the "supertankers" are anything more than a drop in the bucket. We don't go direct on fires; we redirect them, light back burns, choke them cut off their fuels.
We allow them to burn into natural barriers. We do a lot of things with fire, but actually putting it out is often out of the question. It's not a sensible or safe way to do it.
A bigger issue is fire prevention. Most of the homes that burned this time around in Southern California shouldn't have burned. Not because aerial assets weren't on scene fast enough, not because there wasn't enough retardant capability. The homes burned because people have been told for 30 years not to let oak grow up underneath their redwood decks, to build defensible spaces around their homes, and to plan for such fires. The homes burned because people are stupid and stubborn, and never seem to think it will happen to them.
High winds drove those fires, typical of many wildland fires. I've chased fires doing drops in winds over 50 knots. If you've ever seen a 300' fire moving at 50 knots, especially from the ground, you'd think you'd met God. You'd think that you'd met him, and that you were the subject of His wrath, The noise, the heat, the speed, the destruction...cannot be described. Putting a few thousand gallons of retardant on that, or water or foam on that will make the smoke change color for a few minutes...if it gets to the fire at all.
You don't stand in front of a semi truck on the road to assert your right as a pedestrian, and you don't get in front of a fire like that, either. Physics.
If you don't like fire, then prevent it.
Fire in many cases is benificial. With respect to loss of life and structures, much of that can be prevented by using some common sense in removing trees, scrub, and creating defensible spaces around structures. Any firefighter who has had to do urban interface defensive firefighting has seen homes side by side; one burns one doesn't; one had defensible space cut around it while the other didn't. Sad, but people just don't listen, no matter how many times they hear it can happen to them.
Fire is benificial to wildlife, to plant life. It kills diseases, removes deadwood, causes seeds to open, sterilizes soil in some cases where the soil is disease ridden.
Environmentalists have severely damaged the logging industry. The logging industry had become very environmentally friendly, planting as much as was harvested, being a vital part of managing forests. With logging removed to protect often non-existant spotted owls (tastes like chicken), bug kills and excessive old growth take over, leading to prime fire conditions.
Log and manage, and the liklihood for the kinds of fires we've been seeing are decreased.
We're seeing significant changes in weather patterns, with attendant changes in long term fuel moistures...leading to more red-flag days when fire behavior is most likely to be high or extreme. We've seen fires in concert with the santa ana winds that have driven them, often in times of high pressure, with smoke laying low, reducing the chance to fly on them. Flying budgets have been curtailed by congress; we're spending money to bomb the living crap out of third world countries that could be spent bombing forests, or providing lunches for schoolchildren...all to make a sagging president look like he knows what he's doing.
Is the answer to put twenty thousand gallons of water on an aging airliner that was never built for tactical missions, fly it four hundred miles to a fire at ten times the cost of existing tankers, to fly high, be incapable of close low level support, in conditions that present considerable risk to the airplane and those on the ground? In my opinion, it has it's place, but it's a limited one.
As for operating with a 30% cushion over stall...Last year I lost count of the number of times during a run into a fire the rotors and wind shears left me below stall speed, and then in excess of flap speed, and back again, ever second or two as I approached the drop. It's not like flying an instrument approach. It's real world, rubber-meets-the-road kind of flying. Serious business. High drops over the tundra are great, but it's not a realistic scenario for the demands of tactical firefighting.
With regard to "devastating fires," one should note that most of the serious fires we've had have been man-made. First line of defense, stop lighting forest fires.
Second, anybody who has ever fought fire, especially wildland fire, comprehends in a way that cannot be explained that a fire can be well beyond anything mankind can field to put it out. Nothing we have, including the "supertankers" are anything more than a drop in the bucket. We don't go direct on fires; we redirect them, light back burns, choke them cut off their fuels.
We allow them to burn into natural barriers. We do a lot of things with fire, but actually putting it out is often out of the question. It's not a sensible or safe way to do it.
A bigger issue is fire prevention. Most of the homes that burned this time around in Southern California shouldn't have burned. Not because aerial assets weren't on scene fast enough, not because there wasn't enough retardant capability. The homes burned because people have been told for 30 years not to let oak grow up underneath their redwood decks, to build defensible spaces around their homes, and to plan for such fires. The homes burned because people are stupid and stubborn, and never seem to think it will happen to them.
High winds drove those fires, typical of many wildland fires. I've chased fires doing drops in winds over 50 knots. If you've ever seen a 300' fire moving at 50 knots, especially from the ground, you'd think you'd met God. You'd think that you'd met him, and that you were the subject of His wrath, The noise, the heat, the speed, the destruction...cannot be described. Putting a few thousand gallons of retardant on that, or water or foam on that will make the smoke change color for a few minutes...if it gets to the fire at all.
You don't stand in front of a semi truck on the road to assert your right as a pedestrian, and you don't get in front of a fire like that, either. Physics.
If you don't like fire, then prevent it.
Fire in many cases is benificial. With respect to loss of life and structures, much of that can be prevented by using some common sense in removing trees, scrub, and creating defensible spaces around structures. Any firefighter who has had to do urban interface defensive firefighting has seen homes side by side; one burns one doesn't; one had defensible space cut around it while the other didn't. Sad, but people just don't listen, no matter how many times they hear it can happen to them.
Fire is benificial to wildlife, to plant life. It kills diseases, removes deadwood, causes seeds to open, sterilizes soil in some cases where the soil is disease ridden.
Environmentalists have severely damaged the logging industry. The logging industry had become very environmentally friendly, planting as much as was harvested, being a vital part of managing forests. With logging removed to protect often non-existant spotted owls (tastes like chicken), bug kills and excessive old growth take over, leading to prime fire conditions.
Log and manage, and the liklihood for the kinds of fires we've been seeing are decreased.
We're seeing significant changes in weather patterns, with attendant changes in long term fuel moistures...leading to more red-flag days when fire behavior is most likely to be high or extreme. We've seen fires in concert with the santa ana winds that have driven them, often in times of high pressure, with smoke laying low, reducing the chance to fly on them. Flying budgets have been curtailed by congress; we're spending money to bomb the living crap out of third world countries that could be spent bombing forests, or providing lunches for schoolchildren...all to make a sagging president look like he knows what he's doing.
Is the answer to put twenty thousand gallons of water on an aging airliner that was never built for tactical missions, fly it four hundred miles to a fire at ten times the cost of existing tankers, to fly high, be incapable of close low level support, in conditions that present considerable risk to the airplane and those on the ground? In my opinion, it has it's place, but it's a limited one.
As for operating with a 30% cushion over stall...Last year I lost count of the number of times during a run into a fire the rotors and wind shears left me below stall speed, and then in excess of flap speed, and back again, ever second or two as I approached the drop. It's not like flying an instrument approach. It's real world, rubber-meets-the-road kind of flying. Serious business. High drops over the tundra are great, but it's not a realistic scenario for the demands of tactical firefighting.
jsoceanlord
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dash8driver
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furloughfodder
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dash8driver said:avbug,
maybe you should write to evergreen and advise them of their mistake. its obvious that they havent put much thought or research into this project.
I can tell you right now that Dell Smith at Evergreen doesn't put money into something unless it is going to work. It is a done deal.
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