U.S.S. America (LHA-6)

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"SNA 2014: Heat From F-35, MV-22 Continue to Plague Big Deck Amphibs"
by Carlo Muñoz
Published: January 15, 2014 5:39 PM

Source:
http://news.usni.org/2014/01/15/sna-2014-heat-f-35-mv-22-continue-plague-big-deck-amphibs

The Navy is continuing to wrestle with landing deck issues aboard its amphibious ships, tied to flight operations with the F-35B Lightning II Joint Strike Fighter (JSF) and MV-22 Osprey.

Naval Sea Systems Command have drafted a plan to cope with the problem, using a combination of limited operations and deck modifications to allow the JSF and Osprey to fly off the service’s large deck amphibious warships.

Program leaders are working through 14 different ship modifications aboard the USS America (LHA-6), the first ship in the Navy’s new class of large-deck amphibs, designed to preserve the warship’s landing deck, Capt. Chris Mercer, head of Navy’s amphibious warfare shop, said Tuesday.

Along with those modifications, Navy leaders are also limiting the number of flight operations being conducted off of America, as part of deck preservation plan, Mercer said during a briefing at the Surface Navy Association’s annual symposium in Crystal City, Va.

But Mercer did note the strategy in place for the America will not be necessary for the next two of the LHAs in the class.

USS Tripoli (LHA-7) and the yet-unnamed LHA-8, “will be able to carry out “complete unrestricted operations” with the F-35 and MV-22, Mercer said.

The B variant of the F-35 is a short take-off and vertical landing (STOVL) aircraft that produces much more heat when it lands and takes off than the current AV-8B Harrier fighters currently flown off of big decks. Likewise, the exhaust heat from the nacelles of the Osprey has damaged flight decks in the past.

Both warships will be able to handle the deck heat issues, based on the lessons learned from the strategy in place aboard the America, Mercer said.

Deck damage issues related to jet engine downwash from the Osprey and F-35 have long plagued the Navy’s efforts to get those aircraft aboard the amphib fleet.

That said, Navy leaders “fully understand . . . the stresses and failures that the flight deck can accept,” Mercer said.

But when pressed as to why service officials have yet to come up with an answer for the deck heat issue, he said program officials were still struggling with finding a “cost-effective solution” to the problem.

However, Mercer was adamant the operational restrictions aboard America would not affect the combat effectiveness of the ship, given its mission.

The caps “are not going to be a problem” since the primary mission for the Navy’s amphibs was quick assault operations, not sustained warfare missions carried out by the service’s aircraft carriers,” Mercer said.

Since the LHA is not designed to support a sustained air campaign, the deck modifications and operational caps will not affect deck reliability aboard the America“as long as we spread [combat sorties] out,” he said.
 
It is a real surprise that they should have problems with USS America. Laid down in July 2009, after the F-35B had flown.
 
Published on Nov 13, 2013

The amphibious assault ship America (LHA 6), built by Ingalls Shipbuilding in Pascagoula, MS, sails the Gulf of Mexico on builder's sea trials, Nov. 7-9, 2013.

http://youtu.be/WKDyvjek0BY
 
So they've built a class of really good looking powerful ships that unfortunately can't embark most of the proposed air component? Sounds interesting. Well I suppose they can at least throw CH53, Huey's and Cobras off them?
 
The solution that I've heard of for the Osprey has been in place for a while. If the engines have to be run for an extended period prior to launch, they just change the tilt angle of the engines every so often.
 
A random question.
a lot of these LHDs the USMC operates, will operate or already operate STOVL aircraft, namely the harrier or F-35.
Was there no interest in adding ski-jumps to them? like say on the Canberra or Juan Carlos which are also LHDs with ski jumps?
 
A random question.
a lot of these LHDs the USMC operates, will operate or already operate STOVL aircraft, namely the harrier or F-35.
Was there no interest in adding ski-jumps to them? like say on the Canberra or Juan Carlos which are also LHDs with ski jumps?

1) The USMC does not operate these ships, the USN does.

2) No, there is no serious interest in putting ski-jumps on them. Their primary mission is launching an assault wave of helicopters/tiltrotors, and a ski jump would reduce the number of aircraft that can be spotted for launch.
 
The next America-class amphibious assault ship LHA-10 will be named USS Helmand Province.
The LHA-9 was named USS Fallujah in December 2022.
I like this tradition naming modern LHAs either after battles, where US forces (USMC, Army and Navy Seals) took part, or after former WWII aircraft carriers. :)
Better than after US politians.
Source:
 
A random question.
a lot of these LHDs the USMC operates, will operate or already operate STOVL aircraft, namely the harrier or F-35.
Was there no interest in adding ski-jumps to them? like say on the Canberra or Juan Carlos which are also LHDs with ski jumps?
The Navy and Marines are more interested in the ability to get lots of helicopters in the air at once, and the ski jump interferes with that.

If they need more payload than what an F35B can VTOL, well, they have real aircraft carriers with F35Cs or Super Hornets in the area.
 
The Navy and Marines are more interested in the ability to get lots of helicopters in the air at once, and the ski jump interferes with that.

If they need more payload than what an F35B can VTOL, well, they have real aircraft carriers with F35Cs or Super Hornets in the area.
The USMC does not take off vertically in their F-35Bs... they make a run down the flight deck. The only difference between that and using a ski jump is that the flat-deck run uses about 200' more flight deck than the ski jump run does.
View: https://www.youtube.com/watch?v=KJEvTGXyq2E
 
The USMC does not take off vertically in their F-35Bs... they make a run down the flight deck. The only difference between that and using a ski jump is that the flat-deck run uses about 200' more flight deck than the ski jump run does.
View: https://www.youtube.com/watch?v=KJEvTGXyq2E
Not true, you’d need substantially more deck length than 200ft to equate to what a ramp gives you.

The USMC do not operate their jets (AV8B or F35B) at the higher AUWs that the RN wants to. Although short of ALCMs that isnt really an issue.

When you look at the state of USMC husbandry and the effects of that, it does feel like a lot of F35B’s capability is being wasted providing them. The US is paying vast sums of money to not really achieve that much. Nice if you can afford it I suppose.
 
These are the data I've seen. Note that while the ski jump cuts the take-off run for all Harrier models in half, this is not true for the F-35B.

"300 Take-off run in feet from QEC for lightly loaded F-35B
800 Take-off run in feet from QEC for fully loaded F-35B"
Source: AEROSPACE TESTING INTERNATIONAL September 2014

The KPP diagram indicates for USMC while carrying two Joint Direct Attack Munitions and two AIM-120 missiles internally, as well as enough fuel to fly 450 nautical miles, with a 20 knot wind and 20 knots of ship speed for 40 knot WOD then 600 feet is enough. Similarly with a suitable ski jump (on CVF or LHD) at 12-13 degrees then 500 feet is sufficient in same WOD. Nov. 2017
 
The KPP diagram indicates for USMC while carrying two Joint Direct Attack Munitions and two AIM-120 missiles internally, as well as enough fuel to fly 450 nautical miles, with a 20 knot wind and 20 knots of ship speed for 40 knot WOD then 600 feet is enough. Similarly with a suitable ski jump (on CVF or LHD) at 12-13 degrees then 500 feet is sufficient in same WOD. Nov. 2017
Then a ski jump only saves 100ft of takeoff roll when loaded with 2x 1000lb JDAM.

And more importantly from the USMC POV, a ski jump takes two helo spots.
 
Just as an exercise, the ratio in the original USMC KKP (550' flat deck, 450' ski jump) was 1:.8181818181... (1 : .82).

Thus the revised 600' sees a ski-jump run of 492' for a savings of 108'.
If the payload was increased to see a flat-deck take-off run of 800' (max possible for the 843' flight deck of the USN's LHDs & LHAs with the tail of the 51' long F-35B hanging over the aft end) then the ski-jump run would be 656' for a savings of 144'.
 
These are the data I've seen. Note that while the ski jump cuts the take-off run for all Harrier models in half, this is not true for the F-35B.
F-35 is different on a ski jump, indeed STO as it cannot direct all its thrust aft (one major downside of the layout) as the LF is limited and thus core deflects down to counter nose up pitching moment and retain nws.

Its also why the angle tops out. Although Harrier couldnt go steeper anyway for other (operational) constraints.

"300 Take-off run in feet from QEC for lightly loaded F-35B
800 Take-off run in feet from QEC for fully loaded F-35B"
Source: AEROSPACE TESTING INTERNATIONAL September 2014

The KPP diagram indicates for USMC while carrying two Joint Direct Attack Munitions and two AIM-120 missiles internally, as well as enough fuel to fly 450 nautical miles, with a 20 knot wind and 20 knots of ship speed for 40 knot WOD then 600 feet is enough. Similarly with a suitable ski jump (on CVF or LHD) at 12-13 degrees then 500 feet is sufficient in same WOD. Nov. 2017
You are missing the criteria these launches are assessed against. Which is no surprise as this is detail but it is crucial detail.

They are not apples and apples because the ski-jump gets you a lot more safety margin in terms of vertical velocity at the point you assess it. Flat deck and ski jump thus dont compare in the way you seek as you dont back a SJ off because the ballistic profile gives you that velocity margin inherantly.

The “fully” loaded F-35B is way in excess of KPP and USMC loads. I dont think they are actually getting close to them howver and I’m not sure how they’d have tested that. I suspect they havent.


Just as an exercise, the ratio in the original USMC KKP (550' flat deck, 450' ski jump) was 1:.8181818181... (1 : .82).

Thus the revised 600' sees a ski-jump run of 492' for a savings of 108'.
If the payload was increased to see a flat-deck take-off run of 800' (max possible for the 843' flight deck of the USN's LHDs & LHAs with the tail of the 51' long F-35B hanging over the aft end) then the ski-jump run would be 656' for a savings of 144'.
Literally none of that adds up.

You also seem to take public figures at face value. I can only advise that these bear relatively little relation to in service reality.

The USMC desire to avoid ski jumps is partly for helos, but really because they dont understand the system they have. Its like giving a porsche to someone who drives quarter of a mile to work in a 20mph zone, they dont use the capability and dont understand what they have, and frankly waste that cost.

Nice if you can afford it, but that cost comes at the expense of other opportunities.
 
The next America-class amphibious assault ship LHA-10 will be named USS Helmand Province.
The LHA-9 was named USS Fallujah in December 2022.
I like this tradition naming modern LHAs either after battles, where US forces (USMC, Army and Navy Seals) took part, or after former WWII aircraft carriers. :)
Better than after US politians.
Source:
Makes them appear as the Taleban Navy.
 

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