View Single Post
  #1   Report Post  
Robert Haston
 
Posts: n/a
Default Helicopter ferry design

I'm doing a project at work finding alternatives ways to evacuate our HH-60
helicopters (the 1-3 of them that can't fly due to being overhauled or other
maintenance problems) from Patrick AFB (Cocoa Beach, FL) during hurricanes.
We don't shelter them here due to storm surge threat. Right now we call in
C5 cargo planes from Delaware or New Jersey. Remember, this takes two round
trips, one to get them out, another to put them back. If you are wondering
where all your tax dollars go, there's a bunch.

----------------------INSERT LONG STORY HERE---------------------------

Flatbed truck to shelter the birds in the covered barge used to transport
the Space Shuttle external tank (or the convention center in Orlando when
the barge is out) looks like the #1 option. This involves hassles such as
disassembling the tail rotor and such, and still being a tall and wide load.
We would probably have to buy a $45,000 trailer to have it ready.

But as fate would have it, there is an old Navy (no not the clothes store)
dock on base, complete with loading ramp and 5+ feet of depth. If I find a
backup location on the mainland reachable by boat, the "two if by sea"
option looks better. I also stand a decent chance of finding a boat or
barge in the military inventory somewhere. Besides, if you had $45,000 to
spend, would you rather spend it on a trailer or a boat?

----------------------END LONG STORY HERE-----------------------------------

So finally to my point: What would be a good boat design to carry an HH-60?
Our version without gas weighs16,000 pounds. The main front wheels are the
widest point at 10 feet, and hold 90% of the weight. The tail wheel is 30
feet back from the mains, the nose is 11 feet forward, and the tip of the
refueling probe is 20 feet forward of the mains. The vertical center of
gravity is probably about 5' off the ground.

Here is a rather large web page from Sikhorsky detailing the helicopter.

http://www.sikorsky.com/file/popup/1,,167,00.pdf

The trip is only 20 miles, and would be on inland waters with less than 3'
seas, so a ferry or barge would work as well as a landing craft. The only
real difference here is a helicopter isn't square like a truck, it is
roughly sailboat shaped when you look at it tail first. Also, since we are
talking 16 million worth of helicopter here, you want a big stable loading
ramp.

My rough calculations say a hull that fit around the helicopter's shape
would draft less than 2 feet of water. So while I am looking for the
cheapest thing I can find through military or government channels, knowing
the "perfect" design would help.

I am thinking a decked two hull design that would haul two helicopters would
give the best lateral stability and loading ability, which is my #1 concern.
Also, it seems that with about a 12 meter boat and a meter draft, you could
have relatively fine hulls and a decent top speed. Pontoons and deck
sections might be easy to find. Somewhere the Army has hundreds of these
waiting around for WW III.

Aside from specific built designs, knowing ballpark numbers (particularly
horsepower) I could expect for a monohull, catamaran, pontoon or barge
designs that can ferry a 16,000# helicopter or two would be nice.

I'm also open to any other suggestions. One is an "ark" storage building
that would float in case of severe storm surge.


--
Robert Haston
Satellite Beach, FL