Posted on 06/23/2009 11:19:06 AM PDT by SERKIT
Too fast and they rip the scoop plumbing out of the bottom.
Too slow and they simply get too heavy, stop flying and must land.
I believe Canada got 4 of the flying boats. One was lost in a accident, one was lost in a typhoon. The also got all the spare parts which I believe included 60 spare engines. I think they paid $50,000 for the whole lot.
The Martin Museum put in a bid for one of the planes, but lost to the current owner. There are stories in Canada about these planes putting out fires before the firefighters could get to them up there. Also because the planes skim over the lake to pick up a load of water, they can actually put more water on a fire than that DC-10 that CalFire uses.
I remember watching these aircraft landing and taking off from San Francisco Bay back in 1951-2 when I was 5 years old and my Dad was recalled to the Navy and stationed at Oakland Naval Air Station (Now Oakland International). They were sure impressive!
Because the Mars can reload itself and continue fighting fire without having to land, stop, and get refilled, it can put more water/retardant mix on a fire in an hour than ANY OTHER AIRCRAFT, bar none.
This is especially true when there is a large lake, wide river, or the ocean near a wildfire.
Sure, the 747 can drop more in one pass, but it GETS only ONE pass.
Don’t kid yourself, 25 tons of water is a LOT of water!
When the doors open, the aircraft seems to climb 2000 feet in 15 seconds as the water leaves the tanks. It is a sight to behold indeed!
http://www.evergreensupertanker.com/
But wait, there;s more!
From Pistolshot's link at reply #7
http://www.martinmars.com/
The most frequently asked question regarding the Mars is "How do they pick up their water?".
This part of the flying operation is, perhaps, the most demanding in terms of teamwork among the crew.
The Captain executes a normal landing, keeps the the aircraft "on the step" and allows the speed to decrease to 70 knots.
He then passes engine power to the Flight Engineer and selects the scoops to the "down" position.
The ram pressure for injecting the water into the tanks is such that the aircraft is taking on water at a rate in excess of a ton per second.
To account for this added weight, the Flight Engineer must advance the throttles to maintain a skimming speed of 60-70 knots to ensure the aircraft remains on the step.
Pickup time is, on average, 25 seconds.
When the tanks are full, the Captain will have the scoops raised, call for takeoff power from the Flight Engineer and carry out a normal loaded takeoff.
Once airborne, the foam concentrate is injected into the water load (normally, 30 US gallons of concentrate into the 7,200 US gallon water load) where it is dispersed and remains inert until the load is dropped.
Once dropped, the tumbling action causes expansion which converts the water load into a foam load.
This process is repeated for each drop.
In other words, this vital team work is carried out, on average, every 15 minutes per aircraft.
For a Gel drop , the concentrate is injected during the scooping process to allow even mixing.
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That is a hoot..thanks..
Anyone have info as to how this compares with the Spruce Goose, and why the military was developing TWO similar aircraft during the war..?
Yep. The Mariner and the PBY Catalina both had two engines.
I never saw one of these four engine monsters. That is one big airplane!
In the desert west there are also few places that would require the services of airborn firefighting. Sand and suguaros seldom catch fire.
You’re also claiming that Lake Mead is often stormy? If it’s stormy enough to stop the Mars from re-tanking, it’s surely stormy enough to prevent a low pass by a 747, since the 747 was designed to fly at high speed and altitude, while the Mars is in its element at low altitude.
Yes, I slightly underestimated the 747, but stand by the Mars as a far superior platform. 20K gallons in one go, cool. An hour between tank drops, not so good.
The Mars has done yeoman’s service in aerial water drops for years. Granted, only 7K gallons per drop, but only 15 minutes between drops means that less water is needed to contain a fire simply because leaving a fire for an hour (or more) allows that fire to get totally out of hand.
Rather than sniping at each other, let’s agree that it’s a good thing this resource is available for fire supression RIGHT NOW.
BTW just a couple of years ago, the Mars was used to put out a fire 6 miles (and growing closer) from my house, which may have a minor effect on my esteem for it. I love those planes!
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Regards
alfa6 ;>}
I worked at Texas Instruments in Dallas back in the P5M days when we built APS-80 ASW radars for them. One of the ASW engineering group tried to arrange to have one of the P5Ms brought to Mountain Creek Lake by Dallas NAS, but they would not do it, because they said the boats leaked so much that they would probably sink in a day or two. They were expected to be pulled up on the beach any place they landed, amd the beaching facilities at Dallas NAS had been decommisioned, if there were any. I recall seeing big flying boats passing over on the east-west airway through Dallas during WW2 though.
When the 5 missing TBF’s off of Florida in 1945 a Martin Mariner was lost during the search. It was believed to have exploded in the air with no survivors or wreckage ever found.
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