AGS-17 Automatic Grenade Launcher

First in a short series of posts on fairly obscure Soviet weapons.

You do recall that the Soviet Union and China had a series of division sized clashes along their shared border back in the 1960s, right?

Well, they did. And at the time, the preferred Chinese tactic was much as it had been during the Korean War- massed human wave attacks. That’s pretty tough if you’re part of the wave. But its also pretty tough to defend against.  The need to counter possible future attacks, along with reports from the Vietnamese about US automatic grenade launchers just entering service, prompted the Soviets to design their own.

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It took a few years, and never saw action against Chinese forces, but by the early 1970s, the AGS-17 was in widespread use amongst Soviet forces. A fully automatic, blowback operated grenade launcher fired from a tripod, the launcher uses a 30mm x 29 casing, with high explosive fragmentation warhead. It’s fed by a non-disintegrating metallic link belt stored in a 29-round drum.

The launcher can be used in direct-fire mode against targets out to 800m for point targets, or area targets out to its maximum range of 1700m. Interestingly, it can also be used in high-angle fire, almost like an automatic mortar, to engage defilade targets.

The AGS-17 saw extensive use during Soviet operations in Afghanistan, where it proved quite useful firing against Mujahedeen positions, especially RPG and anti-tank teams.  Variants were developed for mounting on vehicles, helicopters, and aircraft.  It has also seen widespread use in Chechnya and other Russian operations.

A refined, lighter version, the AGS-30, has entered service and is slowly replacing the –17.

[youtube=http://www.youtube.com/watch?v=UUrUTaHbLWA]

Inchon, and Operational Maneuver From The Sea

The surprise North Korean invasion of South Korea steamrolled over lightly armed and poorly trained South Korean troops. Even the addition of US airpower and troop units did little to slow the onslaught. The defenders were soon pushed back to a small perimeter defending the port of Pusan. Pusan port was both their logistical lifeline, and presented the escape route should the perimeter fail.

But all was not lost. By the end of the summer of 1950, significant US troop units were available for commitment. Further, the North Korean army had stretched its lines of communication about as far as they could go.

Conventional military thinking called for the deployment of fresh forces into the Pusan perimeter, where eventually they could stage a counterattack, break out of the siege, and force the North Koreans back.

But a glance at the map would show that Korea is a peninsula. With the long shorelines on both coasts, North Korea had been forced to concentrate its ground forces at the Pusan perimeter, and its lines of communication were lightly defended.  These flanks were ripe for attack. And the commander of UN forces in Korea, General of the Army Douglas McArthur, was a past master of amphibious assaults, having used them brilliantly in World War II.  To our eyes some 60 year later, the choice to stage an amphibious assault seems easy.

Except…

The large scale demobilization of the services after World War II included a deliberate choice to mothball virtually all of the Navy’s amphibious warfare capability. The advent of nuclear weapons had convinced Navy planners (and Army planners as well) that any large scale amphibious landing would present a concentrated target tempting an enemy to use atomic weapons against it. A single atomic weapon would not only doom any landing, it would impose catastrophic losses of both shipping and manpower. And so the ability to land an expeditionary force against a defended coast had largely been foregone.

Further, while a brief glance at the map shows Korea as a peninsula, a detailed examination shows it to have some of the most inhospitable coasts, almost completely unsuitable for landings with the technology of the time.  Further, with the slashing of the US amphibious fleet, logistics over any assault beaches would be impossible. It’s one thing to land a force, it’s a far more difficult task to keep it supplied.

General MacArthur, after careful study, chose to conduct an amphibious assault, and chose the port of Inchon (which serves the South Korean capitol of Seoul) as the objective.  Located about halfway up the peninsula on the west coast, Inchon was lightly defended, and was a sufficiently deep envelopment that the North Korean army could not easily shift forces from Pusan to Inchon. But Inchon lies at the end of a long, notoriously treacherous channel with some of the worlds most complex tides. Further, rather than assaulting across open beaches, the troops would have to attack across a seawall onto open paved areas with little or no cover and concealment.

The Joint Chiefs of Staff had grave misgivings about the risks involved. Finding, mobilizing, training and deploying sufficient amphibious shipping and landing craft would be an enormous challenge, and the risks involved. If the Inchon channel was mined, or should the landing force otherwise falter, the invading force might be destroyed in detail.  The failure of any landing attempt would almost certainly cause support for our actions in Korea to collapse.

But the prospect of cutting off the North Koreans and destroying their invading army was tantalizing, and despite their doubts, the Joint Chiefs allowed the commander on the scene to follow his own course.

And so, on this day, September 15, in 1950, elements of the 1st Marine Division, with troops of the 7th Infantry Division in follow on waves, were landed by the US Navy at Inchon, in what is widely hailed as a strategic masterstroke, and one of the most decisive victories ever.

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The landings came as a strategic and tactical surprise to the North Koreans. With their lines of communication threatened, coupled with a breakout by UN forces in the Pusan perimeter, the North Korean army was soon fleeing South Korea in disarray. Had the landing forces at Inchon moved faster to retake Seoul, the North Koreans might have been trapped and destroyed. As it was, they barely managed to retreat not only from South Korea, but northward through their own country to the line of the Yalu River, where soon “volunteers” from the People’s Liberation Army of China would come to their rescue, and dashing hopes for any rapid victory and a lasting peace.

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First Lieutenant Baldomero Lopez, USMC, leads the 3rd Platoon, Company A, 1st Battalion, 5th Marines over the seawall on the northern side of Red Beach, as the second assault wave lands, 15 September 1950, during the Inchon invasion. Wooden scaling ladders are in use to facilitate disembarkation from the LCVP that brought these men to the shore. Lt. Lopez was killed in action within a few minutes, while assaulting a North Korean bunker. Note M-1 Carbine carried by Lt. Lopez, M-1 Rifles of other Marines and details of the Marines’ field gear. Photo number NH 96876. Image Courtesy of the Naval Historical Center.

Mastery of the seas and the ability to land forces upon hostile shores gives a ground commander a freedom of maneuver that allows him to choose the time and place of his assault, and usually provides him the opportunity to attack an undefended or lightly held position. The use of such maneuver to unhinge an enemy is a key to the operational art, whether it be the “Hail Mary” sweep to the west during Operation Desert Storm or the amphibious envelopment at Inchon in 1950.  Since that time, the US has been careful to maintain both the shipping and the expertise to allow it to conduct amphibious assaults worldwide.

Korea

Today marks the anniversary of the cease-fire in Korea in 1953. Often dubbed The Forgotten War, the Korean conflict was a brutal, bruising war that involved retreats, stunning offenses, and a return to trench warfare eerily reminiscent of World War I.

Pfc. Roman Prauty, a gunner with 31st RCT (crouching foreground), with the assistance of his gun crew, fires a 75mm recoilless rifle, near Oetlook-tong, Korea, in support of infantry units directly across the valley. June 9, 1951.

The Army commemorates the Korean War with a slideshow of soldiers in the Korean War.

The Army’s Quest for its Own CAS – Part 1

Earlier Esli made a very astute comment as to what the ground commander needs for fixed winged Close Air Support (CAS):

1. emphasis on CAS within USAF or change the service proponency of the mission
2. operate a/c from rough or austere fields; the same places US Army aviation already operates, and the USMC at least says it is willing to do. (And does in Iraq.)
3. Buy the aircraft, develop appropriate weapons and TTPs, and transition the pilots.

His points are on target, in my humble opinion.  Indeed, I uttered similar observations in the past – particularly advocating for the Army to attain a true fixed-wing CAS capability.  Further, I’d wager if one searched through the archives … say… back to 1953… the same or at least a similar list existed, also penned by veteran combat arms officers in the aftermath of the Korean War.

The Army left the Korean War with pile of lessons learned (or re-learned), and a fixed winged aircraft inventory featuring the Cessna L-19 “Bird Dog” (later designated the O-1 under the tri-service designation system).

Cessna L-19 O-1 Bird Dog__3143

Simple and rugged, the Cessna design continued the basic high-winged, STOL and rough field capable aircraft dating back to World War II.  The “Bird Dogs” served well as liaison and observation platforms.  But the only real “payload” carried were light arms or marking rockets.  During the Korean War the use of airborne artillery observation posts became much more dangerous as jet aircraft made their presence known.   While the Cessna birds were fine for light work like the observation and fire direction tasks, the Army sought something better – that might actually fight back.

At the same time complaints about CAS procedures in Korea began echoing around the Army’s higher ranks.  In some minds the solution was, harkening back to World War II, an Army controlled “tactical air command” assigned to field armies.  After all, the Marines maintained their organic fixed-wing CAS capability.  But within the framework of the Department of Defense, the Army lacked the authority to form such organic capabilities.  And the Air Force was at the time preoccupied with strategic bombing, tactical nuclear strike, and air defense.  The Pace-Finletter Memorandum of Understanding (1952) limited the Army to fixed-wing aircraft under 5000 pounds and only for specific roles.  But the Army could operate helicopters with very few technical restrictions, and began exploring those options.

So through the mid-1950s, the Army worked to improve and make the most of rotary-winged aircraft of the day.  But even that hit a brick wall in 1956 when Secretary of Defense Charles Wilson further delineated the role and restrictions on Army aviation.  Retaining the 5000 pound limit on fixed-wing, Wilson added a 20,000 pound limit on helicopters.  He further limited Army aviation to four roles:

  • liaison and communications
  • observation, artillery spotting, and topographical survey
  • forward area airlift (both cargo and personnel)
  • medical evacuation

Wilson expressly denied the Army any role in CAS. Not only did this quell ideas about fixed wing Army attack jets, it also slowed the development of attack helicopters as the “air cavalry” concept matured.

However, under the guise of communications support and observation roles, the Army could operate forward air control (FAC) aircraft in a limited capacity.  If policy prevented the Army from purchasing attack aircraft, at least the service could field FACs that might pace the Air Force’s fighter-bombers.  While not “on the books” as attack aircraft, perhaps such jet powered FACs might toss a few bombs and eventually evolve into a CAS asset.  Towards that end, the Army tested three Cessna T-37 trainers in 1958-9.

Cessna T-37

The T-37, of course, was just entering Air Force service as a jet trainer at the time (and served in that role up to 2009!).  Tests impressed the Army.  But of course they were comparing the “Tweety Bird” to the old prop planes.  And the type did weigh under 5000 pounds empty.  Needless to say, the Air Force didn’t like this in the least.  So the Army returned the T-37s to the Air Force  (and bear in mind the Air Force later used the A-37 derivative in Vietnam, perhaps proving the wisdom of the Army’s tests).  But the proverbial camel’s nose was under the tent.

Over the next five years, the Army proceeded down three, somewhat distinct, paths in the effort to secure fixed-wing combat aircraft.  Please allow me the liberty of discussing those different courses in detail over a series of posts.

Craig.

The Past, Present and Future of Tactical Radios – Part 3

Continuing from Part 2 – Like much in the U.S. Army, tactical communications evolved little in the years following World War II.   Many of the same radios continued service into the Korean War.  New developments, including long-range multi-channel and radio-teletype, supported division and higher level communications networks, and thus fall outside the scope of this discussion.

AN/PRC-6 U.S. military handi-talkie radio from...
AN/PRC-6 - Wikipedia

In the closing stages of the Korean War, the AN/PRC-6 replaced the SCR-536 hand held radio in infantry platoons.  The PRC-6 introduced FM signal format to the squads and operated between 47 and 55.4 Mhz, with range remained limited to about a mile in good conditions.   Also introduced during the Korea War, three new backpack radios differed only with regard to frequency range.  The AN/PRC-8 covered 20 to 27.9 Mhz, the AN/PRC-9 worked on 27 to 38.9 Mhz, and the AN/PRC-10 operated from 38 to 54.9Mhz.    The AN/PRC-10, of course, being the preferred company radio to allow compatibility with the hand held radios.  One advantage over the World War II sets, the new backpack radios tipped the scales at around 22 pounds (verses 38 for the old SCR-300).   The PRC-8/9/10 ranged just under five miles.

Parallel to these portable radios, the Army deployed a series of vehicle (armor and soft skinned) radios using the RT-66 receiver-transmitter as a building block.  Like the infantry backpack series, the series offered different radios operating on different bands.  The AN/VRC-8, -13, and -16 used the 20 to 27.9 Mhz band.  The AN/VRC-9, -14, and -17 used the 27 to 38.9 Mhz band.  And the AN/VRC-10, -15, and -18 operated on 38 to 54.9 Mhz.  These different designations indicated variations with power supplies or other options.   These vehicle mounted radios had a maximum planning range of 10 miles.  All of these types, both vehicle and portable, continued the use of crystals and vacuum tubes, with all corresponding disadvantages.  Tuner technology limited the frequency range each radio could operate over (and forcing the use of three different frequency bands).  But recall, this was the height of technology at the time.

While the divided frequency bands sounds odd to a modern reader, this fit within the Army’s communication doctrine of the time.  By the “book” infantry regiments operated with a command net and an operational net.  Organic support formations, such as the mortars and anti-tank platoons had their own designated radio nets.  Line battalions maintained an internal command net.  Likewise companies operated on their designated command nets.   By doctrine, the commander could direct the signal officer to create optional networks to support additional reconnaissance or security attachments, medical support traffic, or for liaison with adjacent units. (FM 7-24, Communication in the Infantry Division, dated 1944 describes these radio nets in more detail)   Add to the spectrum of course the fire control networks transmitting back to the fire direction centers.

The number of radio nets, while manageable, required some mechanism to segregate traffic.  The three frequency bands, noted in the radio particulars, happened to allow specific equipment to operate on specific frequency ranges for specific roles.  I am told, but cannot find it referenced in the manuals, that planners allocated the 38 to 54.9 Mhz band for networks company and below.

That worked well in the “square” or “triangular” army formations used through the Korean War.  But in the mid-1950s the Army began reorganizing around a monstrosity known as the Pentomic Division.  Under that concept, each of the five “battlegroups” within the division contained five maneuver companies along with a number of combat support and service support elements.  To manage this multi-headed formation, a battlegroup CP used a command net, an admin net, and a dedicated liaison net.  Add to this nets for the engineer platoon, medical platoon, and supply platoon.  The combat support company had nets allocated for the radar platoon, recon platoon, assault weapon platoon, and heavy mortar platoon.  In short, a proliferation of radio networks, each requiring radio sets and dedicated radio operators.  Communications personnel represented 9% of the battlegroup’s personnel strength!

The technology did not support such a cumbersome command structure.  Command net became crowded, often at the commander’s discretion.  Recall this was the time when the Army fielded the Davy Crockett tactical nuke.  Odds are, the battlegroup commander would prefer to have that section on a tight leash, and not using some radio set on an incompatible frequency.

Doctrine reflected the complexity of the maneuver organization.  The “new” divisional signal manual (again numbered FM 7-24) issued in 1961 exceeded it’s World War II predecessor by over 100 pages.  Setting aside the inadequacies of the battlegroup from a command and control perspective, the communication requirements called for a simplified hardware solution – a single radio set series that used the whole military VHF frequency band.

On the positive side, the Signal Corps continued to refine its Signal Operating Instructions.  While still complicated, standardization reduced some of the training issues.   Printed SOIs included army-wide standard challenge-authentication and encryption tables.  Still verbal encryption of sensitive traffic slowed delivery of the message.

As the U.S. entered the space race, the tactical warfighter faced many of the same problems noted in 1945:

  • Radio range limited to 5 miles (portable) to 10 miles (vehicle mounted)
  • Reliance on easily damaged vacuum tubes.
  • Dependence on heavy batteries for hand and pack radios.
  • Difficulty bringing the radios into operation – again selecting crystals, tuning, and calibrating.
  • Vulnerability to jamming, either from enemy action or natural causes.
  • Vulnerability to intercept, only partly mitigated by the SOI.
  • Poor voice quality.
  • Crowded command networks.

But as a plus, the backpack radio dropped in weight and, in spite of the use of three separate bands, the infantry-armor team spoke on compatible FM radios.   More improvements were in the queue.   I will look next at the “solid-state” VRC-12 family and the Vietnam-era radio experience.