Flood Vehicle ?

[raafif]

just been watching the news about our floods across all of east Australia (north to south).  There seems to be a need for many more helicopters for rescue but also for an amphibious vehicle to go thru rapid flood waters up to 6ft deep -- (where are our Larc 5's ).

Hovercraft are too vulnerable to trees & rapid currents.

Apart from the old DUKW & the Russian PTSM there only seems to be a smattering of possiblilities out there & not many of those types are built.

Any Whif's out there ?

[Nick]

There's always the US Marines Amtracs or the Water Buffaloes they had at D-Day. The original "Landing Vehicle, Tracked" came from the Alligator which was designed for rescuing civilians in the swamps of southern US states.

Or you go for trucks. The classic British Alvis Stalwart is exactly what you need as it was designed to cross the German rivers to reupply forces fighting the Soviets. How about the German Pinz Gauers? with their high wheels?

http://www.amphibiousvehicle.net/index.html is your best resource.

[rickshaw]

The LARC 5s were retired of the Australian Army decades ago.  Never replaced. 

[Hobbes]

Hovercraft are too vulnerable to trees & rapid currents.

I'd think that the Hovercraft is the only vehicle capable of operation in high currents. Thanks to the air cushion, the current can't exert a force on the Hovercraft. In the Seventies, there was a National Geographic expedition using an SR.N6 up the Amazon which iirc went up rapids that were previously thought unpassable by boat.

For rescue ops you'll want one with good position control, maybe using those front thrusters the LCAC has.  

Amphibians aren't too good in flooding conditions: currents can be faster than the top speed of the craft (amphibs are usually slow), the square hull and protruding wheels mean lots of pressure when the current is side-on, and the wheels can get snagged on underwater obstacles.
In these conditions you want either levitation or a shallow hull with powerful water jets.

[beowulf]

could always borrow a few jet boats off the kiwis 

[scooter]

In these conditions you want either levitation or a shallow hull with powerful water jets.

Some Vietnam-era PBRs with their twin jet drives might be doable as well.

Curse the blue water admirals who stopped thinking riverine and littoral warfare after that cruddy little war

[Old Wombat]

Yep, something like a PBR with a reinforced lower hull & keel might do the job, but they'd be a bit expensive to have hanging around just for once in 35/40 years floods.

However, if someone really thought about it, I'm pretty sure modern technology could come up with a fairly reliable & effective amphibian vehicle, which could be used for smaller-scale floods, too.

[raafif]

Wouldn't say it's a once in 50yrs thing -- Nth Queensland & Nthen NSW flood every year to some extent where major roads are cut for at least a few days.

I saw 2 LARCs get bogged in a black-clay channel while practising at my local yacht club years ago -- one pulled the other out but the 2nd got stuck overnight until a recovery truck towed it out  

Was thinking that PBRs etc are too small but the larger NZ jet-boats may have the capacity.

There was the Argosy & the Neptune, a British design that looked very like an LVT-3 Amtrak but was slightly larger & very different in many technical aspects -- ie. powered by an under-floor Meadows flat-12 engine.

In March 1947, Neptunes were used in England when the river Ouse flooded and seven were used to block the gap in a failed dyke while a canvas & sandbag repair was put in place -- some were also used in the Suez Canal in April 1947. One Neptune was given to the Bovington Tank Museum but scrapped in 1959.

Italy modified a M-548 with bouyancy cells, ducted props & water jets and the current British Aquatrack - rather like a larger M-548 cargo-carrier able to swim in Sea State 5 is a progression of this idea & seems to be the best option currently.

[Old Wombat]

Wouldn't say it's a once in 50yrs thing -- Nth Queensland & Nthen NSW flood every year to some extent where major roads are cut for at least a few days.

Yes, they do but this is a once in 35/40 year event, which is why I think boats are less likely to be effective under normal Qld/NSW flood conditions that amphib's. Under current conditions you could almost run an Armidale class patrol boat inland to Toowoomba.

Whatever Flood Event Rescue Vehicle (FERV) anyone comes up with, remember;

1. it will have to be tough enough & manoeuvrable enough to cope with heavy water-borne debris, such as trees, cars & houses;
2. it will be required to have sufficient power to advance up-stream, against the current, at speed (say 20kts against 20kts, so 40 kts max?);
3. it will need to be able to move quickly from one flood affected area to another quickly & probably by road;
4. it should be able to carry approximately 20 people (including crew) &/or up to 3 tonnes of supplies; &
5. it must be extremely reliable & fuel efficient (to minimise the fuel & spares taking up room necessary for emergency supplies for the victims).

[rickshaw]

Wouldn't say it's a once in 50yrs thing -- Nth Queensland & Nthen NSW flood every year to some extent where major roads are cut for at least a few days.

Yes, they do but this is a once in 35/40 year event, which is why I think boats are less likely to be effective under normal Qld/NSW flood conditions that amphib's. Under current conditions you could almost run an Armidale class patrol boat inland to Toowoomba.

Might be a bit of portage involved.  Toowomba is on the otherside of the Great Dividing Range watershed, to the ocean, mate.

Whatever Flood Event Rescue Vehicle (FERV) anyone comes up with, remember;

1. it will have to be tough enough & manoeuvrable enough to cope with heavy water-borne debris, such as trees, cars & houses;
2. it will be required to have sufficient power to advance up-stream, against the current, at speed (say 20kts against 20kts, so 40 kts max?);
3. it will need to be able to move quickly from one flood affected area to another quickly & probably by road;
4. it should be able to carry approximately 20 people (including crew) &/or up to 3 tonnes of supplies; &
5. it must be extremely reliable & fuel efficient (to minimise the fuel & spares taking up room necessary for emergency supplies for the victims).

One of the local Sheriff departments in the US after Hurricane Katrina was using an 8 wheeled, amphibious APC which they'd acquired from somewhere.   It could carry 10 passengers plus a crew of two.  Seemed to work OK for them.   Can't find a picture of it but it was one of the failed contenders for the Stryker program IIRC.

[Old Wombat]

Might be a bit of portage involved.  Toowomba is on the otherside of the Great Dividing Range watershed, to the ocean, mate.

This I know, old son, but, given how much water is covering Qld, I though it wasn't a huge stretch of reality...... for a "whif" site, anyway.

[deathjester]

How about the LAV-25 Piranha? Doesn't that carry 15 -20 people, and have full amphib capability, with water jets?

[Weaver]

Wanna go shopping? Here's Hans Rosloot's excellent Amphibians site, which has just about the most comprehensive list I've ever seen, though he's a bit shaky on some of the pure military vehicles:

http://www.amphibiousvehicle.net/frame.html

[Weaver]

Personally, I think you'd be mad to take any surface vehicle out on a rescue mission during the initial phase of a flash flood when the waters are moving fast and full of debris: even a hovercraft can be hit by a car/tree/house. The only vehicle that should be doing rescues in those conditions is a helicopter. Once the flash is over and you're dealing with "simple" flooding with low-energy water, then most amphibious vehicles become more useful.


This looks good: http://www.amphitruck.com/Index.htm

[nebnoswal]

The LARC 5s were retired of the Australian Army decades ago.  Never replaced. 

I wouldn't say decades ago, they went to east timor in 1999.  And I remember coming ashore on the back of one at Cowley beach on exercise back in 2004.  They were retired not long after, most finding new homes in the tourist industry.

How about the LAV-25 Piranha? Doesn't that carry 15 -20 people, and have full amphib capability, with water jets?

More like 8, at a tight squeeze.  They used in the NT back in early 2000's when Katherine flooded.  There are plenty based in Bris, 2/14 QMI, but it depends on how many personnel have been recalled from leave to operate them!