On Tue, May 6, 2008 at 11:48 AM, Doug LaRue <[EMAIL PROTECTED]> wrote:
> ** Reply to message from Legatus <[EMAIL PROTECTED]> on Tue, 6 May > 2008 > 11:27:05 -0500 > > > You know air water drops as a means of fire suppression is not generally > > effective. They are often used simply as a very expensive (sometimes at > the > > cost of pilots life) PR method. People think that is what they should > see, > > so that is what they are given. Not to say that they don't have a place, > > just that most of the time, they are for show, while all the real > > firefighting still happens on the ground. > > I don't know about the "for show" part but it's pretty obvious that when > the > winds pickup and the fire fronts expand, it becomes a spot protection > fight > and cleanup once the winds subside. If they are so much for show, are all > those involved in air support so naive to be risking their lives for show? > Can > they all be that gullible to be fooled into thinking they are doing > something > helpful when it is just a marketing game? Just trying to get a handle on > this. > > I do know there are some pretty strange reactions which cause me to > question > the intelligence behind some decisions. For instance, I also remember two > helo's spending over an hour on one burning home in Julian where they > just kept dropping water on the roof of the home. The water shed off the > roof > as should be expected from a functional roof. Only when the fire gutted > the > inner structures and the roof collapsed, did water drops knock down any > flames. Over an hour of wasted time for two helo's when the last 15 > minutes > of water drops did the job. > > If indeed the water drops are more show than go, then we are wasting > billions > on these fire fighting mechanisms and it is wide spread. After all, air > drop > equipment gets called in from all over the state and country from/to many > different firefighting organizations. That's one heck of a conspiracy > theory > but I am open to data listing the lack of effectiveness. > > I work with the NWCG, and they are quite aware of the value, and lack of value to water drops. They also know the value of keeping the politicos out of their business. Water drops keep the politicians and public happy with the efforts. They don't hesitate to shift these resources to a place that the water drops would be helpful, when it is appropriate. The pilots are not naive about their role and when it is effective, and when it is not. Basically they will deliver water drops constantly, because if they don't, then they have to deal with the political and PR fallout. When there is a useful place for the drops, then that is where they will happen. There is also constant experimentation with chemical fire suppressors that may increase the effectiveness of air drops by large margins. Water drops are most effective when they can reach the fuel source, and saturate it. That way the fuel either burns slowly or not at all. When the drops are done of the center of large fires, or away from the edges of the fire the water evaporates before it reaches the fuel. Its effects are negligible at that point. Yes increasing the airs humidity can slow the fire, but the evaporation happens so quickly that the humidity rise is only temporary, so the effects are not enough for effective fire suppression. -- KPLUG-List@kernel-panic.org http://www.kernel-panic.org/cgi-bin/mailman/listinfo/kplug-list
