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-   -   Future Carrier (Including Costs) (https://www.pprune.org/military-aviation/221116-future-carrier-including-costs.html)

KenV 14th Apr 2017 18:01


Originally Posted by Just This Once... (Post 9740116)
Aside from the imagination, anti-ship ballistic missiles are recognised as a credible threat. The sensor/targeting systems tend to be multispectral these days to provide both all-weather capability and anti-jam capabilities. Back in the 70's the US mastered the art of terminal manoeuvring and active radar homing on the Pershing II missile, but time and technology has marched on.

Regarding the movement of a CVN - well in truth they really don't move all that much when compared to the inbound speed. At say 13m/s it takes around 25 seconds for the stern of a cruising CVN to pass over the same spot vacated by the front of the flight deck. The maximum lateral displacement it can achieve in that time is also not a lot.

By contrast the kinetic penetrator of the inbound weapon can be nudging 7000m/s (over 13,000kts) making a CVN look almost stationary, with just a small amount of lead to calculate. The other concerning aspect of such speed is that even a direct hit from an intercepting missile may do little to influence the final trajectory - in the same 25 seconds that it took the ship to move its own length the inbound will complete its final 75 miles. Of course, MIRVs complicate matters further.

Keep in mind that the very characteristics you cited above make for a very difficult and complex system. A hyperspectral targetting system that can reliably function through the heat of reentry is very difficult to design and build. To put 7000m/s in perspective, the muzzle velocity of the high velocity kinetic penetrator of a 120mm tank gun is less than 1,700m/s, or less than one fourth the speed of your ballistic missile penetrator. Maximum effective range of the tank penetrator is 3000m. That's a function of loss of kinetic energy AND targeting precision with range. This means your hypothetical multispectral targetting system needs to be orders of magnitude more precise than the tank's targeting system while trying to see thru the heat of re entry and subsequent flight at 7000m/s, all while resisting defensive EW.

As for intercepting such a system, the point is to intercept the re-entry vehicle which contains the sensors, computer systems, and manuevering systems, not the (presumably inert) penetrator. The Aegis system and Block 3 SM missiles can do a midcourse intercept (exoatmospheric), but that would likely require an Aegis ship stationed along the flight path between the launcher and carrier. The Block 4 can do an intercept during re-entry.

As for the speed of the CVN, that is indeed negligible for the terminal phases of the intercept. But the missile's total flight time is measured in tens of minutes. A carrier moves at roughly 1km/minute. Thus it is 10 to 20 km from its position relative to when the missile was fired. That's a pretty large expanse of ocean to search (over 1200 sq km) in a very short time as it re-enters and will require very robust maneuvering of the re-entry vehicle to make the intercept. This is a very very different and much much more complex problem than the one the Pershing system designed and built to solve. After re-entering, the Pershing MARV did a 25G pull up and a 30nm glide to the vicinity of its target. There was not a lot of kinetic energy left after the glide and great precision was not required since it had a W85 "dial a yield" nuke warhead.

I'm not saying taking out a carrier using a ballistic missile is not possible. They are indeed a real threat. But it is a much more difficult and complex problem than most folks realize. And assuming a nation did that successfully, the US would remain very capable of a devastating retaliation without resorting to nukes. They are essentially an effective area denial weapon. But so are mines. The mines are much much cheaper, but have the disadvantage of denying friendly as well as enemy entry into the area.

Just This Once... 14th Apr 2017 19:31

You have linked high speed with a precision problem, when the reverse can be true. You also introduced a premise that the target position would only be known at launch and then lost over many minutes so requiring a new search. Modern targeting information can come from off-board sources and form part of the updated guidance solution.

The Pershing example from nearly 50 years ago was to demonstrate the controllability and the ability for sensors to survive re-entry. What was incredibly difficult all those years ago is considerably easier now - the hard miles have been done. The Soviet Union's own anti-ship ballistic missile was fielded in the late 70's and had a CEP of around 300m against a ship so relied on a nuclear tip to close the final margin of error. Given modern systems and suitable money they could do much better today; but for money and effort you have to look at the Chinese.

As for the politics of the US devastating a country that managed to hit a CVN during a conflict, well that's not my area of expertise. I would like to hope that the US could take and accept a hit on a CVN in harms way doing its job, without triggering total war - but you never know.

The USN has flexed its muscles with CVNs rather effectively for many decades in a rather one-sided use of firepower. It is understandable that potential adversaries have worked hard to provide a credible counter. Your point about them providing an effective area denial weapon is well-made and reflects current USN thinking. The countermeasure cycle is without end.

Onceapilot 14th Apr 2017 21:33

Your points are well made JTO.:ok: I tend to think that, the Flat Top Fanatics often miss the point that, despite the romantic allure of shipborne air power, it remains vulnerable to total negation due to its complete reliance upon the fickle support of bouyancy. :uhoh:

OAP

gr4techie 14th Apr 2017 21:50


Originally Posted by glad rag (Post 9739931)
One issue Spaz, it appears that they wish to operate from a line of sun shelters, well I guess we shall find out just how humidity proof both the avionics and airframe really are then rofl.

Current fj fleets have dehumidifiers fitted when in hangars / shelters

WE Branch Fanatic 14th Apr 2017 21:54

I tend to think that, the land based airpower Fanatics often miss the point that, despite the romantic allure of land based air power, it remains vulnerable to total negation due to its complete reliance upon the fickle support of the host nation, and the fixed location of the airfield not being attacked. I wonder if anyone has ever built a weapon that can devastate a fixed location?

Onceapilot 14th Apr 2017 22:02

WEBF

Are you imitating something? I am flattered! :)

OAP

MSOCS 14th Apr 2017 22:32


Originally Posted by gr4techie (Post 9740612)
Current fj fleets have dehumidifiers fitted when in hangars / shelters

The sun shelters are open-sided and of a style similar to those you'd expect to see used by the USAF in the Middle East, therefore you'd be trying to dehumidifying the planet! As I tried to explain, the jet has been tested ad nauseum in conditions far exceeding darkest Norfolk, plus those of most overseas locations we can expect to operate in. Total non-issue; "fake news" etc.

SpazSinbad 14th Apr 2017 23:02

For MAD DOGS & Englishmen to get out of the NOON DAY SUN: [they are smart Dutchies but...]

https://www.defensie.nl/binaries/lar...2/img_1211.jpg

https://www.defensie.nl/binaries/lar...2/img_1211.jpg

FODPlod 14th Apr 2017 23:13


Originally Posted by WE Branch Fanatic (Post 9740615)
I tend to think that, the land based airpower Fanatics often miss the point that, despite the romantic allure of land based air power, it remains vulnerable to total negation due to its complete reliance upon the fickle support of the host nation, and the fixed location of the airfield not being attacked. I wonder if anyone has ever built a weapon that can devastate a fixed location?

Who needs ballistic missiles?

George K Lee 14th Apr 2017 23:57

Ken...Your 1200 km2 appears to be based on the assumption that the boat can do anything from carrying on straight ahead, to stopping dead and immediately proceeding at full speed in any direction. I have never seen an aircraft carrier do that.

glad rag 17th Apr 2017 13:28


Originally Posted by MSOCS (Post 9740646)
The sun shelters are open-sided and of a style similar to those you'd expect to see used by the USAF in the Middle East, therefore you'd be trying to dehumidifying the planet! As I tried to explain, the jet has been tested ad nauseum in conditions far exceeding darkest Norfolk, plus those of most overseas locations we can expect to operate in. Total non-issue; "fake news" etc.

..."Really"...

of course as these basic models are due re manufacture shortly it wont really matter what happens to them..

However it's good to see some testing has been done on time and in budget then.....lol

MSOCS 17th Apr 2017 14:00

What's due remanufacture shortly glad rag?

Turbine D 17th Apr 2017 17:20

MSOCS,

Is Secretary James’ Block 3F full combat capability certification, as required by the Fiscal Year 2016 NDAA, still valid?
Answer by the DOT&E: For many reasons it is clear that Lot 10 aircraft that will begin delivery in 2018 will not initially have complete Block 3F capability.
- The program currently has 270 Block 3F unresolved high priority (Priority 1 & Priority 2 out of a 4 priority categorization) performance deficiencies, the majority of which cannot be addressed and verified prior to the Lot 1o aircraft deliveries.
- The program currently has 17 known and acknowledged failures to meet contract specification requirements, all of which the program is reportedly trying to get relief from the SDD contract due to lack of time and funding.


One of the items that must be redone for full Block 3F certification is retesting of the electronics in severe conditions within the flight envelope and operation theater. The new Block 3F electronics generate more heat requiring additional cooling to keep them within temperature operational limits. As time goes on, more deficiencies are bound to be discovered. All of the aircraft delivered without the full Block 3F capability will have to be reworked.

MSOCS 17th Apr 2017 20:02

Turbine, aware. I'd still like to know what GR thinks needs to be rebuilt...

PhilipG 17th Apr 2017 20:43


Originally Posted by MSOCS (Post 9743665)
Turbine, aware. I'd still like to know what GR thinks needs to be rebuilt...

Possibly the F35B spars that have cracked under testing and need to be replaced, the ones that were once too heavy in Titanium, or has this situation been resolved?

MSOCS 18th Apr 2017 07:40

Redesign incorporated in subsequent LRIP, but previous jets have been fixed.

PhilipG 18th Apr 2017 09:37


Originally Posted by MSOCS (Post 9744028)
Redesign incorporated in subsequent LRIP, but previous jets have been fixed.

Thanks for the update, I hope the weight penalty was not too high.

MSOCS 18th Apr 2017 10:05

One can just imagine the rising outrage of the 'weight watchers' and their subsequent disappointment when it didn't noticeably affect aircraft performance.

SpazSinbad 18th Apr 2017 11:23

For those concerned about their weight - here is some old news....

F-35B Variant Quotes from DOT&E 2016

"..."...Weight management of the F-35B aircraft is critical to meeting the Key Performance Parameters (KPPs) in the Operational Requirements Document (ORD), including the Vertical Landing Bring-Back (VLBB) requirement, which will be evaluated during IOT&E. This KPP requires the F-35B to be able to fly an operationally representative profile and recover to the ship with the necessary fuel and balance of unexpended weapons (two 1,000-pound bombs and two AIM-120 missiles) to safely conduct a vertical landing.

▪▪ The program completed the final weight assessment of the F-35B air vehicle for contract specification compliance in May 2015 with the weighing of BF-44, a Lot 7 production aircraft. Actual empty aircraft weight was 32,442 pounds, only 135 pounds below the planned not-to-exceed weight of 32,577 pounds and 307 pounds (less than 1 percent) below the objective VLBB not‑to‑exceed weight of 32,749 pounds.

▪▪ The actual weights of production aircraft through Lot 8 have increased slightly, with the latest Lot 8 aircraft weighing approximately 30 pounds heavier than BF-44. Weight estimates for Lot 10 aircraft and later project weight growth of an additional 90 pounds, primarily due to additional EW equipment.

▪▪ Known modifications to the 14 Lot 2 through 4 F-35B aircraft, required to bring those aircraft to the Block 3F configuration, are expected to potentially add an additional 350 pounds, which will push their weight above the objective not-to-exceed weight to meet the VLBB KPP. This KPP will be evaluated during IOT&E with an F-35B OT aircraft.

▪▪ Estimates for FoM weight growth include an additional 250 pounds, which will exceed the vertical landing structural limit not-to-exceed weight of 33,029 pounds for the Lot 2 through Lot 4 aircraft. This additional weight may prevent these aircraft from being upgraded to the Block 4 configuration...." page 63
http://www.dote.osd.mil/pub/reports/...2016f35jsf.pdf

KenV 18th Apr 2017 18:00

First, please understand I enjoy technical discussions and am not arguing against the premise of ballistic anti-ship missiles.

You have linked high speed with a precision problem, when the reverse can be true.
That depends on the nature of the warhead. I got the impression that the warhead being discussed 1) is "dumb" (no sensors, etc) and 2) is hypersonic (7000 m/s!) and derives all its killing energy from its kinetics (no explosives). For the warhead to have retained that kind of velocity all the way to its target it would have to be released/ejected from the sensor section at very high altitude, and since it's inert it must fly a ballistic trajectory from then on. That means the sensor(s) must have long range while seeing thru the heat of re-entry and simultaneously have extraordinarily high precision to direct the ballistic warhead to the distant target with any hope of hitting it. Modern main battle tanks have very high precision sensors and yet they have an effective range on the order of a few kilometers. The system being described would require orders of magnitude greater precision.

You also introduced a premise that the target position would only be known at launch and then lost over many minutes so requiring a new search. Modern targeting information can come from off-board sources and form part of the updated guidance solution.
It would appear that if tensions had escalated to the point that a hostile nation would attempt to sink a CVN, that both sides would engage in extensive EW. Maintaining a datalink to the missile during its flight in such an environment would seem to be highly unlikely. Further, the survival of the "off-board" sensor system that is tracking the CVN would also seem to be highly unlikely.

The Pershing example from nearly 50 years ago was to demonstrate the controllability and the ability for sensors to survive re-entry.
Pershing had an ablative heat shield to protect the radar sensor from a mach 8 re-entry velocity (about one third the velocity of this system's claimed terminal velocity of 7000 m/s.) The entire re-entry system did a 25G pull up maneuver after reentry to bleed speed, followed by a 30nm controlled glide. The radar did not switch on until the final terminal phase of the flight at considerably lower altitude to update the inertials so as to provide a 100m CEP for that final terminal maneuver. That is totally different than the system being described.

What was incredibly difficult all those years ago is considerably easier now - the hard miles have been done.
Indeed. But the system being described operates totally differently than the Pershing system and the resulting problem is orders of magnitude more difficult than the Pershing problem. So basically, the "miles" of this new system are much longer and immensely more difficult than the "done" miles. And BTW, the "done" miles were done by the USA, which has not shared that technology with its allies, much less its adversaries.

I would like to hope that the US could take and accept a hit on a CVN in harms way doing its job, without triggering total war - but you never know.
I believe you are correct and "hits" on various US ships over the past decades tends to confirm that. However, the system being described is of a "carrier killer", specifically designed and used not just to "hit" a carrier, but to sink it outright. Assuming it is successful, that to me is quite a different kettle of fish that will result in a rather devastating counter blow even if that blow is "proportional." For perspective, use of 59 Tomahawk missiles to destroy an air base was considered "proportional" for the use of a few chemical weapons against civilians. It would seem (but cannot be confirmed) that a "proportional" strike for the sinking of a CVN would be considerably more devastating.

The USN has flexed its muscles with CVNs rather effectively for many for peresepdecades in a rather one-sided use of firepower. It is understandable that potential adversaries have worked hard to provide a credible counter. Your point about them providing an effective area denial weapon is well-made and reflects current USN thinking.
During the cold war, the entire Soviet fleet was a sea denial system specifically designed to deny access to US carrier battle groups. In my opinion, anti ship ballistic missiles are a land based version of the same thing. They would be great for example to place CVNs in jeopardy in any kind of operation to retake Taiwan. But to prevent US projection of military power anywhere else? In my opinion, not so useful.


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