Sea Sparrow

In the late 1950s, the US began to realize the threat Soviet long range anti-ship missiles such as the SS-N-2 Styx and AS-1 Komet presented to the fleet. The primary counter to such missiles was to intercept the launch platforms at long range, either by attack aircraft sinking ships equipped with the Styx, or fighters shooting down bombers carrying Komet.

The backup was the long range  Talos, Terrier and Tartar guided missile equipped cruisers and destroyers.

But the cost and weight of the missile ships meant there were barely enough to support the fast carrier task forces. The huge numbers of other warships, amphibious warfare ships,  and auxiliaries were left with only the virtually useless twin 3”/50 gun for air defense.

And so, the Navy embarked on a program to field a low cost, lightweight missile system for the self defense of ships such as the Knox class ocean escorts.

For several years, the Navy cooperated with the US Army developing the RIM-46 Mauler. It was eventually cancelled for technical reasons. The Army instead opted to field a ground launched version of the AIM-9 Sidewinder at the MIM-72 Chapparal. The Navy considered adopting it as well, as it was very light, and very cheap. The problem was, the missile seeker, based on the AIM-9D, had no front quarter engagement capability. And almost by definition, any self defense missile system means any target you’re shooting at is pointing right at you, that is, you only see its front quarter. That meant a radar guidance system was needed. And what radar guided missile did the US Navy have handy? The AIM-7E Sparrow III, used on the F-4 Phantom!

With very minimal modifications, the AIM-7E became the RIM-7E* Sea Sparrow. The Mk112 ASROC pepperbox launcher was modified to become the 8 round box launcher for the Sea Sparrow. Guidance was by the Mk115 director. The Mk115 was a crude system, in which an operator optically tracked the target, manually traversing and elevating the director. The director also had two continuous wave illuminator radars.

648px-Sea_Sparrow_Mark115_Fire_Control_Director

Mk115 manned director for Basic Point Defense Missile System (Sea Sparrow).

The director operator would be cued to incoming threats by voice commands from the ship’s Combat Information Center and associated search radars.

The Sea Sparrow had Semi-Active Radar Homing. That is, it guided on the reflected radar energy that bounced off the target being illuminated by the Mk115. Because the Mk115 had a fairly wide illumination beam, that allowed for some degree of minor tracking errors on the part of the operator. Not much, but some.

The missile, launcher, and director were collectively known as the Basic Point Defense Missile System, and BPDMS would be installed on many Knox class frigates, amphibious warfare ships, and fleet auxiliaries.

But BPDMS had an obvious shortcoming. The director operator had to be able to see the target. At night, or in inclement weather, the chances of a successful intercept plummeted to just about 0%.

[youtube https://www.youtube.com/watch?v=AdNn5uY542M]

Our NATO allies also faced a similar missile threat. And so, working with several European allies, the Navy began work on an improve Sea Sparrow system, on that came to be known variously as either Improved Point Defense Missile System (IPDMS) or more commonly, NATO Sea Sparrow Missile System (NSSM).

NSSM saw improvements to all three components of the system. The missile used an improved motor, and utilized folding wings so it could fit in a smaller launcher box. The new launcher was lighter, and of course, used smaller launcher boxes. The biggest improvement was in the director system. The manual tracking of the Mk115 was abandoned. Instead, the Mk95 radar director automatically tracked the target via radar, as well as providing illumination for missile guidance.

NSSM formed the basic air defense weapon of the 31 ships of the DD-963 Spruance class destroyers, as well as arming most aircraft carriers, quite a few amphibious ships, and many auxiliaries. On board the Spruance class, the NSSM was controlled by the Mk91 Fire Control System. The ship’s primary air search radar, the SPS-40, wasn’t really that great at detecting missile threats. The Mk 91 consisted primarily of the NSSM with its missile, Mk29 launcher, Mk95 directors, and the addition of the Mk23 TAS. Mk23 TAS, or Target Acquisition System, was a relatively short ranged 2D radar with a rapid rotation rate optimized for detecting low flying anti-ship missiles. After detecting a target, the Mk23 cues the Mk95, which in turn cues the Mk29 in azimuth and elevation, and then illuminates the target at launch.

Our Canadian friends operate a vertical launch version of the Sea Sparrow in the Mk48 VLS system, but otherwise, it works similarly to ours.

The final version of the Sea Sparrow is so radically different, it’s actually a new missile, the RIM-162 Evolved Sea Sparrow Missile. Using the latest guidance section and warhead of the Sparrow family, the ESSM has an entirely new, much larger motor, and instead of using mid-body mounted wings for steering, uses after fins for steering and mid-body strakes for stability. It can be fired either from the Mk29 launcher, from the Canadian Mk48 VLS, or can be “quad packed” with four missile in once cell of a Mk41 VLS, such as those aboard the DDG-51 Burke class guided missile destroyers. When fired from existing Mk29s, it’s guided by the Mk91 Fire Control System.  When fired from the Mk41, it is guided by the ships Aegis system and its Mk99 illuminators.

Similar guidance systems are used by allied navies, such as the Dutch.

[youtube https://www.youtube.com/watch?v=Qd2U_jOqzsA]

*Under the tri-service missile designation system, AIM stands for “Air Launched Intercept Missile, while RIM is Ship Launched Intercept Missile.

SeaCat

The classic 40mm Bofors cannon was clearly obsolete versus high speed jet aircraft by the 1950s. The Royal Navy could ill afford to equip most of its fleet with expensive, and large, guided missile systems such as the Sea Slug missile system. So Shorts Brothers developed the lightweight, relatively inexpensive SeaCat missile system in the early 1960s.

A small, lightweight, subsonic missile using Command to Line of Sight Guidance, SeaCat could be mounted on just about any warship, and was for many Royal Navy ships the only air defense aboard. The gunner used a set of binoculars on a pedestal mount to track the target, and the guidance system relayed steering commands via a radio link.  Theoretically, as long as the gunner kept the target within the crosshairs, the missile would guide to the target.

It was also widely exported to the usual British client states.

In reality, the system, while very reliable, was not terrible capable. During the Falklands war in 1982, out of over 80 SeaCat firings, only one Argentine Skyhawk was brought down. Interestingly, the Argentinians also used SeaCat and its land based variant, Tigercat, though they scored no kills.

[youtube https://www.youtube.com/watch?v=oDGkTeVxsOs]

TOW Missile in Vietnam

Today, the US designed TOW missile is almost ubiquitous, being used by more countries than you can shake a stick at. It’s also in use by the Free Syrian Army rebels in that nasty little civil war they have going on.

But in 1972, the TOW was brand spanking new. The Army had its eye on the stupendous fleets of Warsaw Pact tanks in Europe, and wanted to get a good idea of just how well TOW would work, particularly mounted on a helicopter.

As it happened, the famous Easter Offensive of the Vietnam War broke out just about the same time that TOW was ready for operational testing. While we generally think of the Vietnam War as one fought by infantry supported by artillery in jungles or rice paddies, there was a shift in the Easter Offensive. The US had spent the years from 1964 to 1972 perfecting counter-insurgency warfare. But the the North Vietnamese Army in 1972 launched an entirely conventional, mechanized, invasion of South Vietnam. Large numbers of tanks, APCs and fleets of trucks supported the invasion. The Army of the Republic of Vietnam was ill equipped to deal with that mechanized threat. Only the prompt and massive application of American airpower staved off the invasion.

And one small part of that was the combat debut of TOW, mounted on UH-1B gunships.

XM26_Drawing

towviet2

The success of the interim XM-26 TOW armament system would inspire the Army to mount a similar system on its fleet of AH-1 Cobra gunships, which would be the primary attack helicopter in the Army fleet until introduction of the AH-64 Apache and its Hellfire missile in the late 1980s.

[youtube https://www.youtube.com/watch?v=UpzXVvemY0s]

Pike Tiny Guided Missile and some others

Raytheon (and a few other companies) has put a lot of emphasis on designing ever smaller precision weapons.  Taking it down to just about the smallest I’ve seen, they’re developing (on their own dime, btw) what they call Pike.

pike

That’s a guided missile designed to be fired from a standard 40mm grenade launcher.

They’re not shooting precision-guided bullets — yet.

But Raytheon may be the closest yet, with a tiny guided missile a soldier can launch from a rifle-mounted grenade launcher.

Meet the Pike, a 17-inch-long, laser-guided munition that Tucson-based Raytheon Missile Systems is developing on its own dime in hopes the U.S. Army and perhaps other allied armies will buy it.

The Pike and other small guided munitions Raytheon has developed in recent years meet a growing demand for precision, targeted strikes that leave minimal “collateral damage” — death or injury to civilians and property damage — in an era where enemies often hide in crowded areas.

“Nowadays we’re not worried nearly as much, about mass formations of an adversary’s armor,” said J.R. Smith, Raytheon’s director of advanced land-warfare systems. “A lot of it now is insurgents, and they’re in light vehicles or you’ve got people planting IEDs (improvised explosive devices).

One of the challenges an American infantry platoon faces in combat is that when you get right down to it, the organic firepower of a US platoon isn’t that much better than say, it’s Taliban opponents. Rifles? Check. Machine guns? Check. Grenade launchers? Check. Unguided rockets ? Check. There’s no decisive edge there. Oh, you might have your Javelin with you, and that gives you good overmatch against an enemy machine gun team. But Javelin is very big, bulky and really expensive.

The traditional American answer to this problem is to draw from outside assets. Fire support from company or battalion mortars, supporting artillery batteries, fixed or rotary wing air support. Which, that will always be the way  we fight combined arms.

But it sure would be nice if, rather than having to wait for supporting fires, a US platoon could almost instantly use organic assets to achieve fire superiority, ending the fight that much quicker.

We mentioned LTG McMaster the other day, and his role as the Army’s chief innovator. One of his consistent pushes since he was a two star at Ft. Benning was increasing the lethality of the rifle squad and platoon.

Should Pike work as advertised (or even reasonably close to it) that would seem to me a very handy capability to have.

Raytheon’s press release describes it as having a semi-active laser guidance system, and a range of about a mile and a half. At two pounds, a rifle platoon could carry a goodly number of these, limited more by cost than by weight.

It doesn’t look like they actually test fired any yet (or at least, release video of any tests), so let’s look at some other videos of small precision guided weapons.

[youtube https://www.youtube.com/watch?v=DnL-NxtfrKQ]

[youtube https://www.youtube.com/watch?v=PdM0Ci13eJA]

I’d kinda like to see a shipborne MLRS/SDB variant for suppression of enemy air defenses. Mate a seeker from the AGM-88E AARGM on to the warhead and you’ve have a pretty nifty tool for attacking S-300 air defense systems in the littorals.

OTR-21 Tochka/SS-21 Scarab

So Jason and I discussed this bit of news while recording another podcast. A UAE Patriot battery successfully intercepted an SS-21 Scarab short range ballistic missile fired from Yemen by Houti rebels* at coalition forces in or near Saudi Arabia.

What is the SS-21 Scarab? The Russian designation is OTR-21 Tochka (Point). It’s a solid fuel guided short range missile. Depending on the variant, it has a range of from 40 miles to about 110 miles.  Doctrinally, a Soviet army commander would use these to attack deep behind our lines at key installations, such as supply or fuel depots, airfields, air defense installation, or key command and control nodes. It was, and is, a potent weapon.

Here’s Ukrainian forces launching a pair at Russian forces in eastern Ukraine.

[youtube https://www.youtube.com/watch?v=rcA3LtpiQOQ]

Not everything works all the time.

[youtube https://www.youtube.com/watch?v=m1KQGEuFM0E]

*Which we suspect are really Iranians from the Quds Force or IRGC.

Footage of the Last Hours of USS Wasp CV-7

 Shortly after 1440 on 15 September 1942, in the waters of the Solomon Islands, USS Wasp (CV-7) was struck by three torpedoes from the IJN submarine I-19.   The impact point was directly below the AVGAS distribution station, which was in operation when the torpedoes struck.   Within minutes, Wasp was engulfed in flames, roaring like a furnace, punctuated by powerful explosions from built-up gasoline vapors.  Ammunition and aerial bombs began to detonate from the heat, and inside of an hour, Captain Forrest Sherman ordered Wasp abandoned.   She burned well into the evening before torpedoes from USS Lansdowne (DD-486) finally sank her.

lea

wasp-burning-and-sinking

When I was a young lad, I read an excellent book on the Solomons Campaign.  In it, the author described Wasp as burning like a torch, and how, as darkness fell, sailors on other ships could see her glowing red from the fires inside.   When Wasp finally slipped beneath the waves, it was said she emanated a loud and eerie hissing as her hot steel sank into the sea. Watching the footage above, one understands that such a description, like Tom Lea’s famous painting, is hardly hyperbole.

In all, 193 sailors died on Wasp, and 366 were wounded.   Forty-three precious aircraft also went down with her. She had been in commission just 28 months.

In the 37 weeks of war since December 7th, the US Navy had lost Langley (CV-1), Lexington (CV-2), Yorktown (CV-5), and Wasp (CV-7).  Also soon to be lost was Hornet (CV-8), sunk at Santa Cruz on 26 October 1942.   Hornet, however, would be the last US fleet carrier lost during the war.

H/T to Grandpa Bluewater

Hellfire Longbow at Sea

The US Navy’s LCS ships lack a short range missile. The planned NLOS missile was cancelled. So the Navy is now looking at using a vertical launch system equipped with the AGM-114 Hellfire missile, particularly its Longbow millimeter wavelength radar seeker variant.

[youtube https://www.youtube.com/watch?v=FCmbK1MM0I4]

In a recent test series performed by the US Navy, eight Army/Lockheed martin AGM-114L ‘Longbow Hellfire’ missiles destroyed seven fast naval craft simulating fast attack craft performing swarm attacks, similar to those practiced by the Iranian navy in the Arabian Sea and the Persian Gulf. The test was part of the engineering development test of the Surface-to-Surface Missile Module (SSMM), for use on littoral combat ships (LCS).

The tests, that took place in June 2015 in the Atlantic Ocean, off the coast of Virginia, evaluated the integration of the vertically-launched AGM-114L Longbow Hellfire missile system for the SSMM solution. In this application the missile receives initial target data from a surface search radar or an airborne radar on a helicopter, before launch. After launch, it activates the onboard millimeter wave seeker to find the target. The system has an initial range of eight kilometers and features fire-and-forget and multi-mode capability. The multi-purpose warhead ensures effectiveness against various types of attacking craft.

Spike Missile Development

First, there’s real potential for confusion here. The Israelis developed and fielded a family of small guided missiles marketed under the name Spike.

Coincidentally, the subject of this post is an in-house development project for a  small guided missile called Spike. I think I posted about this last year, but I thought I’d share an update.

The Naval Air Warfare Center Weapons Division at China Lake has a long history of developing aerial weapons for the Navy. Probably its most famous design is the AIM-9 Sidewinder family of missiles. Of course, most weapons design work is actually performed by contract to major defense industry. But China Lake likes to keep its hand in.  After all, how can you ride herd on the contractors if you don’t have a working knowledge of weapon design?

To that end, NAWC decided back in 2001 to design a very small missile. The goal wasn’t explicitly to field a weapons system, but rather to serve as a reality check on the state of the art, and as a learning tool for NAWC engineers to see what the challenges of designing a weapon were.

Buy using existing technology, often commercial off the shelf items, and with a clear vision of what they wanted to achieve, over time, the team developed a missile just over two feet long, and weighing just five pounds.

[scribd id=272892196 key=key-ZzQWMSJqJrKCBvJgUPil mode=scroll]

The first version had fixed fins, which obviously has some limitations. The “Block II” iteration has folding fins, so the round can be launched from a combined storage/launch tube, much like the TOW.

[youtube https://www.youtube.com/watch?v=ZOskwt7M_r4]

Spike isn’t a POR, or Program of Record, so there isn’t really much development money, nor is there a stated requirement for it to fulfill, which would be needed before it could be produced and fielded.

One of the interesting things noted in the presentation above is one of my favorite buzzwords- the 80% solution. If you have a system that solves 80% of your problems (say, machine gun nests ) it’s almost bound to be relatively inexpensive. It’s striving for that last 20% capability that causes costs to skyrocket.

About that F-35 vs. F-16 dogfight…

The interwebs and Facebook exploded this week with the latest revelation that the F-35 Joint Strike Fighter is a dog that can’t dogfight.

David Axe’s post has set off a firestorm of criticism over the inability of the F-35 to outperform the 40 year old F-16. Everyone who has access to the internet is up in arms over this horrible failure.

But here’s the thing. The JSF is not really a fighter. Or rather, the emphasis is on strike, more than on fighter. It’s a bomb truck. It does also have a robust air to air capability, but that role is somewhat secondary to its ability to attack ground targets.

The F-16 was conceived during the last years of the Vietnam war, and designed immediately following it. COL John Boyd’s Energy/Maneuverability Theory had a very large impact on its configuration. The ability of outmaneuver potential Soviet threat aircraft was the paramount concern of the design. And the aircraft had to be able to outmaneuver because of the limitations of the armament of the day. To wit, the plane John Boyd and the Fighter Mafia wanted was to be dirt simple, with only the most crude radar for cueing weapons, and armed only with a pair of AIM-9P Sidewinder short range missiles, and the M61 Vulcan 20mm cannon.

The other jet fighter the Air Force was buying at that time, the F-15 Eagle, took a completely different approach, with the biggest radar they could stuff into a fighter sized jet, and a whopping 8 air to air missiles, four of the big AIM-7 Sparrows (the primary armament) and four Sidewinders, as well as a gun.  The Eagle also was built with the E/M theory very much in mind, but primarily saw itself as a beyond visual range fighter, picking off Soviet MiG-21s and MiG-23s before they could even return fire.

The anti-F-35 camp (the loudest members of which are probably David Axe, Eric L. Palmer, and Pierre Sprey*) insist that any fighter simply must follow the E/M theory, or it is utterly worthless.

The problem is, E/M theory isn’t applicable to just airplanes. Turns out, it applies pretty well to air to air missiles also. And whereas a manned airplane can’t really go much above 9G without harming the meatware, missiles have no problem pulling 60G or more.  Building agility (high G capability) into an airplane involves tradeoffs. The structure has to weigh more or it will crack sooner, and conversely, intense efforts at weight reduction have to be implemented, as weight factors strongly into the equation. Having reached an effective plateau of about 9Gs, it simply makes more sense to concentrate on enhancing the maneuverability of the weapon, not the airplane.

[youtube https://www.youtube.com/watch?v=6YMSfg26YSQ]

Furthermore, it should be noted, there’s quite a few people pushing back against Axe’s sensationalistic piece. Far from being the true test that shows once and for all the F-35 is a POS, it was in fact, a first look, aimed at finding out not so much how well the F-35 performed against the F-16, but rather at what parts of the flight control software could be improved to give the F-35 more maneuverability, particularly at high Angles of Attack (AoA).  It appears the F-35 used in the test, AF-2 the second build “A” model for the Air Force, was also using flight control software that restricted certain portions of the envelope. And my sources also tell me the test took place during a time when there were restrictions on the engine performance. While the pilot might have no restrictions on throttle movement, the Full Authority Digital Engine Control (FADEC) was programmed in a manner that would restrict some of the output.

From Aviation Week:

“…The operational maneuver tests were conducted to see “how it would look like against an F-16 in the airspace,” says Col. Rod “Trash” Cregier, F-35 program director. “It was an early look at any control laws that may need to be tweaked to enable it to fly better in future. You can definitely tweak it—that’s the option.”

Emphasis mine.  The F-35 has already demonstrated a 9 G capability. It’s cleared through a flight envelope up to 50,000 feet, and a speed of Mach 1. 6. It was a deliberate decision to accept a considerably lower top speed than the Mach 2.0 of the F-16, particularly since most air to air engagements take place in the transonic regime, from about Mach 0.8 to maybe Mach 1.1.

Incidentally, the F/A-18 Hornet is really a 7.5G fighter, and yet fought the way it was intended to be fought, it has an excellent reputation against the US Navy’s Aggressor F-16s.

The gang at f-16.net aren’t exactly impressed with Axe’s article.

Nor is SMSgt. Mac at Elements of Power

UK Defense Journal points out that in other exercises more representative of real operations than a canned BFM scenario, the F-35 has performed quite well against the F-16.

Over the last few years there have been occasions where a flight of F-35s have engaged a flight of F-16s in simulated combat scenarios, the F-35s reportedly won each of those encounters because of its sensors and low visibility.

C.W. Lemoine, who has flown both the F/A-18 and the F-16, points out a few reasons why the Axe article is, in his words, garbage.

There are a great number of valid reasons to criticize the F-35 program, from its very inception envisioning one jet operating as a vertical jump jet, a carrier jet, and a conventional runway jet. The costs associated with the avionics and computer programming have been astonishing.  The deliberate spread of subcontracts across every possible Congressional district as a defense against cancellation is another issue worthy of debate.

But taking one small canned scenario, one intended not to see if the F-35 could out fight the F-16, but rather explore the flight envelope, and proclaiming that it invalidates the entire development program, is the type of sensationalistic clickbait reporting that does little to inform the public on the actual state of the program.

 

 

*Pierre Sprey is a statistician and a music producer. He also still contends to this day that the F-15 is a failure, in spite of a combat record of something like 105-0 in air to air combat. Take his words with that thought in mind.