The Melting Deck Plates Muddle - V-22 on LHD deck....

On Dec 9, 11:22*pm, Mike wrote:
StrategyPage.com
December 2, 2009

The Melting Deck Plates Muddle

by James Dunnigan

Earlier this year, the U.S. Navy discovered that the heat from the
MV-22's gas turbine engines, which blow their exhaust right on to the
deck of the LHD while waiting to take off, caused high enough
temperatures to the steel under the deck plates, to possibly warp the
understructure. This was already a known potential problem with the
new F-35B vertical takeoff jet fighter.
So now the Navy has two hot new aircraft that require an innovative
solution to the melting deck problem. The Navy also discovered that
the exhaust heat problem varied in intensity between different classes
of helicopter carriers (each with a different deck design.)

The Navy is looking for a solution that will not require extensive
modification of current carrier decks. This includes a lot of decks,
both the eleven large carriers, and the ten smaller LHAs and LHDs.
This is shaping up as another multi-billion dollar "oops" moment, as
the melting deck problem was never brought up during the long
development of either aircraft.

Previously, the Harrier was the only aircraft to put serious amounts
of heat on the carrier deck, but not enough to do damage. But when you
compare the Harrier engine with those on the V-22 and F-35B, you can
easily see that there is a lot more heat coming out of the two more
recent aircraft. Someone should have done the math before it became a
real problem.

Here is the problem laid out in numbers


F-35 and V-22: Keeping it Cool on Deck
Posted by Graham Warwick at 6/24/2009 8:43 AM CDT

We've heard how the stealthy F-22 and F-35 are flying thermos bottles,
struggling under the huge heat loads imposed by their powerful engines
and systems. Well it seems the latest generation of vertical-lift
aircraft is turning the flight decks of US Navy amphibious assault
ships into frying pans.

blog post photo

Photo: US Navy

The initial culprit is the MV-22 tiltrotor, but the big concern is the
STOVL F-35B, which is due on deck after 2012. With nacelles tilted and
rotors turning, hot exhaust from the Osprey's engines is buckling the
decks, and Navy studies warn repeated buckling will cause deck failure
at 40% of planned ship life. F-35B exhaust plumes are expected to have
a "severe thermo-mechanical impact" on the structure and non-skid
surface of the flight deck.

That's according to a new solicitation from the Office of Naval
Research, which is looking for new ideas for flight deck thermal
management. The solicitation is looking for alternatives to a DARPA/
ONR program that is already looking at "cooled heat pipe technologies"
to overcome the thermal issues.

It's not a trivial problem. For the MV-22, where the exhausts are
close to the deck when the nacelles are vertical, buckling has been
observed after just 10min of sitting on the deck, rotors turning. The
F-35B will be in STOVL mode for a fraction of that time, but is
expected to cause even more heating of the deck.

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.

blog post photo
Photo: Lockheed Martin

Based on measurements taken during recent hover-pit tests, Lockheed
Martin does not believe there will be an issue with deck temperatures.
One acknowledged area of concern is the combined auxiliary/emergency
powerpack, or IPP, which exhausts downwards on the STOVL aircraft. (It
exhausts upwards on the F-35C carrier variant to protect deck crew,
but downwards on the F-35B and CTOL F-35A to save weight and gain fuel
volume.)

The IPP has two modes: bleed and bleed-and-burn. In bleed mode the
exhaust is relatively cool, Lockheed says. In bleed-and-burn, fuel is
burned in the IPP to generate more power, and exhaust temperature
rises. Because of operator concerns about surface heating, Lockheed
says the pilot will have the ability to switch the IPP back to bleed
mode if holding on the runway, or deck.

http://www.aviationweek.com/aw/blogs...6-08049291946b

In article a12ee279-bf71-45e8-8d2e-2ee21c1d9159
@m38g2000yqd.googlegroups.com, says...
On Dec 10, 12:23*am, "Malcom \"Mal\" Reynolds" atlas-
wrote:
In article
3f72b032-2be2-4377-a180-01d7a81404fe@d2
1g2000yqn.googlegroups.com,


*Mike wrote:
StrategyPage.com

The Navy is looking for a solution that will not require extensive
modification of current carrier decks. This includes a lot of decks,
both the eleven large carriers, and the ten smaller LHAs and LHDs.
This is shaping up as another multi-billion dollar "oops" moment, as
the melting deck problem was never brought up during the long
development of either aircraft.

Previously, the Harrier was the only aircraft to put serious amounts
of heat on the carrier deck, but not enough to do damage. But when you
compare the Harrier engine with those on the V-22 and F-35B, you can
easily see that there is a lot more heat coming out of the two more
recent aircraft. Someone should have done the math before it became a
real problem.

Use what NASA uses for the shuttle?
Wouldn't cost that much at all

It is a BIG f-ing "oops", and I think that the Navy's RFP is a little
silly. They want a product that doesn't require alteration to the
flight deck, is easily applied and repaired, and doesn't cost much.
Presumably it has to be environmentally friendly too. It wouldn't
surprise me if someone asked for it to be organic as well.

I dunno, I'd assume that NASA could provide some expertise there, but
whether or not the Navy actually is willing to ask for it is another
story.

Maybe they need the mil-spec version of the nanoparticle insulating
paint:

http://www.industrial-nanotech.com/n...me_protect.htm


Mark Borgerson

"Mark Borgerson" wrote in message
...

Maybe they need the mil-spec version of the nanoparticle insulating paint:

AFAIK, that stuff is snake oil.

Vaughn

On Thu, 10 Dec 2009 15:53:26 +0200, "Roger Conroy"
wrote:


"Bill Kambic" wrote in message
.. .
On Thu, 10 Dec 2009 02:57:36 -0800 (PST), Jack Linthicum
wrote:

snipped for brevity

Or use the rocket launch technique and spray water across the take-off
area.

Probably less than optimal. Large clouds of hot, salt water steam
would be an annoyance (at a minimum) to the deck crew. It would also
be a highly corrosive material that could serious complicate
maintenance of both ship and aircraft.

Use of fresh water would likely be an excessive demand on the
evaporators.

The piping of cooling water suggested earlier would be a better idea.
It would likely be cheaper that major modifications such as a "ski
jump" and permit the continued use of the vertical capability of the
aircraft.

A water cooled heatsink built into a part of the deck designated for "hot"
aircraft makes a lot of sense.

Indeed. And since naval architects know a LOT about piping cooling
water for lots of stuff the area could be quite large giving use for
most, if not all, of the deck. That's a major boost for opertional
efficiency.

On Dec 10, 8:53*am, "Roger Conroy"
wrote:
"Bill Kambic" wrote in message

...



On Thu, 10 Dec 2009 02:57:36 -0800 (PST), Jack Linthicum
wrote:

snipped for brevity

Or use the rocket launch technique and spray water across the take-off
area.

Probably less than optimal. *Large clouds of hot, salt water steam
would be an annoyance (at a minimum) to the deck crew. *It would also
be a highly corrosive material that could serious complicate
maintenance of both ship and aircraft.

Use of fresh water would likely be an excessive demand on the
evaporators.

The piping of cooling water suggested earlier would be a better idea.
It would likely be cheaper that major modifications such as a "ski
jump" and permit the continued use of the vertical capability of the
aircraft.

A water cooled heatsink built into a part of the deck designated for "hot"
aircraft makes a lot of sense.

You could have a place underneath to stash beer, like the old sub-
mariners did.

On Dec 10, 7:24 am, Jack Linthicum
wrote:
On Dec 10, 8:53 am, "Roger Conroy"
wrote:



"Bill Kambic" wrote in message

.. .

On Thu, 10 Dec 2009 02:57:36 -0800 (PST), Jack Linthicum
wrote:

snipped for brevity

Or use the rocket launch technique and spray water across the take-off
area.

Probably less than optimal. Large clouds of hot, salt water steam
would be an annoyance (at a minimum) to the deck crew. It would also
be a highly corrosive material that could serious complicate
maintenance of both ship and aircraft.

Use of fresh water would likely be an excessive demand on the
evaporators.

The piping of cooling water suggested earlier would be a better idea.
It would likely be cheaper that major modifications such as a "ski
jump" and permit the continued use of the vertical capability of the
aircraft.

A water cooled heatsink built into a part of the deck designated for "hot"
aircraft makes a lot of sense.

You could have a place underneath to stash beer, like the old sub-
mariners did.

In electronics, we have similiar problems, we usually solve using Al
heat sinks, fan air cooled, as the cheapest. Screw a few Al heat sinks
to the bottom of the locations of the deck permited to take the heat
and engage any fluid to cool it, even water if space is tight, yawn.
Ken

On Dec 10, 2:00*pm, "Ken S. Tucker" wrote:
On Dec 10, 7:24 am, Jack Linthicum
wrote:



On Dec 10, 8:53 am, "Roger Conroy"
wrote:

"Bill Kambic" wrote in message

.. .

On Thu, 10 Dec 2009 02:57:36 -0800 (PST), Jack Linthicum
wrote:

snipped for brevity

Or use the rocket launch technique and spray water across the take-off
area.

Probably less than optimal. *Large clouds of hot, salt water steam
would be an annoyance (at a minimum) to the deck crew. *It would also
be a highly corrosive material that could serious complicate
maintenance of both ship and aircraft.

Use of fresh water would likely be an excessive demand on the
evaporators.

The piping of cooling water suggested earlier would be a better idea.
It would likely be cheaper that major modifications such as a "ski
jump" and permit the continued use of the vertical capability of the
aircraft.

A water cooled heatsink built into a part of the deck designated for "hot"
aircraft makes a lot of sense.

You could have a place underneath to stash beer, like the old sub-
mariners did.

In electronics, we have similiar problems, we usually solve using Al
heat sinks, fan air cooled, as the cheapest. Screw a few Al heat sinks
to the bottom of the locations of the deck permited to take the heat
and engage any fluid to cool it, even water if space is tight, yawn.
Ken

Troll them in the water, saves having all those pipes.

Bill Kambic wrote in
:

On Thu, 10 Dec 2009 15:53:26 +0200, "Roger Conroy"
wrote:

A water cooled heatsink built into a part of the deck designated for
"hot" aircraft makes a lot of sense.

Indeed. And since naval architects know a LOT about piping cooling
water for lots of stuff the area could be quite large giving use for
most, if not all, of the deck. That's a major boost for opertional
efficiency.


Just take a Mk7 JBD and mount it appropriately. It probably would not
need the hydraulics to raise/lower as for conventional takeoffs.

scott s.
..

On Dec 10, 2:23*am, Dan wrote:
David E. Powell wrote:
On Dec 9, 11:22 pm, Mike wrote:
StrategyPage.com
December 2, 2009

The Melting Deck Plates Muddle

by James Dunnigan

Earlier this year, the U.S. Navy discovered that the heat from the
MV-22's gas turbine engines, which blow their exhaust right on to the
deck of the LHD while waiting to take off, caused high enough
temperatures to the steel under the deck plates, to possibly warp the
understructure. This was already a known potential problem with the
new F-35B vertical takeoff jet fighter.
So now the Navy has two hot new aircraft that require an innovative
solution to the melting deck problem. The Navy also discovered that
the exhaust heat problem varied in intensity between different classes
of helicopter carriers (each with a different deck design.)

The Navy is looking for a solution that will not require extensive
modification of current carrier decks. This includes a lot of decks,
both the eleven large carriers, and the ten smaller LHAs and LHDs.
This is shaping up as another multi-billion dollar "oops" moment, as
the melting deck problem was never brought up during the long
development of either aircraft.

Previously, the Harrier was the only aircraft to put serious amounts
of heat on the carrier deck, but not enough to do damage. But when you
compare the Harrier engine with those on the V-22 and F-35B, you can
easily see that there is a lot more heat coming out of the two more
recent aircraft. Someone should have done the math before it became a
real problem.

Make a designated VTOL area and add shuttle style tiles there.

* *It wouldn't stand up to mechanical abuse. While the tiles will
withstand heat they would crumble under the weight of taxiing aircraft
and deck vehicles.

Dan, U.S. Air Force, retired- Hide quoted text -

- Show quoted text -

Use carbon composite plates. They're the materials on the wingtips
(not the infamous bottom that killed Columbia). Those are more heat
resistant, and less brittle if I'm not mistaken.

On Dec 10, 2:00*pm, "Ken S. Tucker" wrote:
wrote:
In electronics, we have similiar problems, we usually solve using Al
heat sinks, ...
Ken-

In my country we put the electronics on the other end of the
airplane.