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Old December 12th 09, 06:33 PM posted to rec.aviation.military,sci.military.naval,rec.aviation.military.naval
Jack Linthicum
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Posts: 301
Default just curious The Melting Deck Plates

On Dec 12, 12:30*pm, D Wright wrote:
Jack Linthicum wrote:
On Dec 12, 11:43 am, D Wright wrote:
ONR is looking for thermal management technologies that can keep the
deck surface temperature below 300ºF when exposed to MV-22 exhaust
plumes for 90 minutes before takeoff, and F-35B exhaust plumes for 2
minutes when landing. And cooling the deck is not enough - any
solution has to be compatible with the deck's non-skid coating. It
also has to be affordable and capable of being installed below deck or
retrofitted above deck. Tall order.
“Structural Evaluation of an LHD-Class Amphibious
Ship Flight Deck Subjected to Exhaust Gas Heat from a MV-22 Osprey
Aircraft,” they note that deck buckling occurs at a temperature of
160oF to 170oF. Where does the 300oF limit originate?
Response: The 300 degree F is derived from the temperature limit of
the tires on aircraft.
How concentrated is the heat flux, how large an area is involved in
the 24,000BTU/min heating? I have had difficulty getting any numbers
and the information heat flux given in the BAA did not include an area
component.
Response: A range of 3-foot to 10-foot diameter is suggested.
Max exhaust temperature anticipated?
Response: This is tightly controlled. A range of max temperatures
could be 1000– 1700 deg. F.
http://www.onr.navy.mil/~/media/File...ements/BAA/09-....
With hot aircraft tires being an additional concern, what about the
impact on the feet of the flight deck crew, refueling hoses, "mule"
tires, etc? *It seems like this heat issue may take on the dimensions of
a "systemic" problem.


It's just the nature of naval air ops that once an aircraft (weapons
system) is established, it will become heaver, more powerful, and the
tempo of operations will increase.


3-10 feet in diameter, just like the spec said.


Is the 'spec suggesting temps of 1,000+ F are of no consequence outside
of a ten foot circle? *Where is residual heat in the equation? *What if
the ten foot circle moves?


Then the Osprey is moving