The M47 "Dragon"
The M47 "Dragon" is an anti-tank guided missile system developed by Raytheon in the mid 1960s and fielded by both the US Army and Marines starting in 1975. Produced by both McDonnell Douglas and Raytheon (and by parts, about a dozen sub-contractors), the M47 would serve as the United States' primary man-portable medium anti-tank system for nearly 30 years until being completely replaced by the FGM-148 Javelin starting in 1999. It was issued to infantry units at the squad level, serving alongside the M72 LAW as a means of increasing an infantry unit's ability to deal with heavier armored threats, such as Soviet T-55, T-62, and T-72 tanks. It was even dropped with paratroopers, using a special sling and (amusingly) honeycombed cardboard pad.The original weapon was a two element Semi-Automatic Command Line of Sight (SACLOS) system that utilized a reusable Command Launch Unit (CLU - a "sight" or "tracker") to allow a gunner to steer a disposable, tube-launched HEAT missile (the M222) to its target via a physical enameled-copper wired connection.
Two different types of launch units were part of this system - a day sight and a night sight. Both house the same electronic guidance systems, which use an IR detection system that keys to an IR flare on the rear of the missile. Aiming reticle are simple cross-hairs, with a basic, unmarked stadia rangefinders - tanks in profile that fill the full stadia are in range, while tanks front on
The daysight (SU-36/P) has 6x fixed optical magnification with a 6° field of view. Other than guidance electronics, the 7.72" long tracker is unremarkable. This tracker weighs 6.8 pounds, and does not require its own battery - that is incorporated into the rear of the launch tube itself. Unfortunately, I have no good word on in-period price per day unit as yet.
The nightsight (AN/TAS-5) features a 4x fixed optical zoom over a 3.4° by 6.8° field of view. It is an older style red-black passive IR thermal imaging display that uses rechargeable batteries and requires coolant bottles to successfully make the night vision elements work - these both last for two hours apiece. Otherwise, this 14.5" long tracker works much the same way as the daysight, steering the missile more-or-less where you aim the crosshair - it can even be used dismounted as a simple - if heavy - night vision optic. The night unit is much heavier than the day sight, coming in at 21.65 pounds (including both a battery - itself being a 1.5 lb BA-30 - and a 1.5 lb coolant bottle), and makes an audible humming noise in use. Cost for this tracker is $30,500 in FY78.
The M222 missile propulsion is two stage. Inside the tube, it uses a small rocket motor (also called a "gas generator"). This burns out before the rocket leaves the tube, which blows off the rear shock absorber and propels the missile out without subjecting the operator (or its guidance wire) to a rocket blast. In flight, propulsion is maintained by arrays of thrusters along the body (three banks of ten motors) which also double as guidance - these begin to fire approximately 40 yards out from the launcher and produce a distinct "popping" noise. As the tracker picks up where the missile is and compares it to where it should be, it sends commands along the wire which get converted into signals to fire bursts of thrust. Stabilization is provided by three canted fins, which deploy upon exiting the tube.
The 29.39" long, 11.5" wide, 13.486 pound FGM-77 missile carries a 101.6mm diameter, 1.716 pound octol HEAT warhead at a rate of 100 meters (109.4 yards) per second and launched from a 10.514 pound, 44.1" long disposable fiberglass tube. The missile had a range of 1,000 meters (1093.61 yards). Total carry weight for one complete round round is 25.29 pounds. Price for one round is $4,500 in FY78.
After 71 yards (65m) of travel, the missile actually arms and the warhead is live.
Dragon missile tubes and trackers are typically carried detached from each other, with each tracker having their own carry bag (the night tracker's bag having dedicated space for three batteries and three coolant bottles). When the weapon needs to be deployed, the 44.1" long tube is unslung and its integral bipod unfolded (automatically ejecting the front shock absorber). The CLU is then attached and the weapon is ready to fire. To launch the missile, a safety button on the trigger unit is depressed with the right thumb and then the trigger lever itself is squeezed - after about a one second "arm" period, this launches the missile. Missile launch generates significant backblast: danger at 30m, and still a potential hazard out to 50m - do not fire this weapon indoors, and wear hearing protection if you are within 30m of the launcher!
After launch, the gunner can utilize the sight to guide the missile towards the target. As long as the gunner keeps his sights on the target and does not accidentally sever the wire on terrain or distance and does not pan the tracker faster than the missile is capable of keeping up with, the rocket will strike the target out to its maximum wire length. If the wire is severed (including reaching max range) the missile will fire all thrusters and send itself straight up into the sky. If the tracker is panned too quickly and sight of the missile is lost, the missile will ground itself.
The weapon will perform as expected between -25°F and +145°F, and can be stored between -65°F and +155°F without damage.
The actual performance of this weapon is somewhat lackluster. The missile travels slowly, and does not pack as much punch as was desired on the receiving end. For all its payload, the M222 manages only to penetrate up around 18.9" RHA. As a wire-guided piece, the gunner must stay in line of sight to the target, which is further complicated by the rather loud and distinctive popping noise its solid-fuel guidance/propulsion motors make - this puts the operator at considerable risk. What's worse, is the range is pretty poor considering the weapons it was expected to come up against (best wear your frag vest!). The launcher had something of a delay between hitting the bang-switch and actually sending the missile - approximately one second - during which there was a distinctive whine. Anecdotes point to this arm period causing the gunner to tense up, leading to loss of control of the missile when the sudden weight left his shoulder in a hurry - this results in the missile grounding due to rapid tracker panning (or it simply getting pointed too close to the ground). This problem is unaided by the apparent tendency of the missile to be very responsive to input, with users claiming that the missile could easily be lead astray by the user (such as when breathing - something the later field manuals hint at).
One Desert Storm veteran commented that, when deployed on the Iraqi border, his unit was less concerned about the general possibility of facing Iraqi tanks than having to actually use the Dragon against them. As you can imagine, the attributes of this weapon did not lead to troops much confidence in it.
As early as 1980, contracts from the US Army for a replacement were awarded to a number of major defense contractors. Little came of this, however, as the contracts were repeatedly funded and defunded over the course of three years, after which it was completely cancelled. Another replacement attempt (the Infantry Man-portable Anti-armor Assault Weapon System (IMAAWS) program), lasted just two months. The Marines, however, stayed the course with their M47 Dragon improvement projects, and worked with McDonnal Douglas to produce a Product Improved variant ultimately named "Dragon II".
By 1987, over 110,000 missiles were provided or sold to various nations, with more than another 100,000 in US inventories. It was used by several nations, including (but not limited to) Sweden, Iran, the Netherlands, and Thailand.
Dragon II
Also known as the "Generation II Dragon" and the FGM-77B, the Dragon II was adopted in 1985 and incorporated a number of improvements, focusing on improving penetrative effects. The old 101.6mm warhead was replaced with a new 122mm warhead (which seems to be based on Swiss inputs from the early 1980s, as they themselves also operated the weapon). This larger warhead incorporated an additional 1.87 pounds of octol explosive, bringing the warhead itself to 3.586 pounds and overall weight of the missile to 15.356 pounds.
The increased warhead potency brought a remarkable increase in penetration - tests conducted by the Marines indicate a consistent penetration of 35" of RHA - an 85% increase over the earlier missile. This defied the calculated potential of 30.26", a phenomenon attributed to a unique configuration of the shaped charge. This improved rocket now goes by the name Mk 1 Mod 0.
The new warhead was actually presented as an upgrade kit - while new production missiles were manufactured, extant missiles in USMC (and Swiss) inventory could be retrofitted with the upgrade package. Other than the warhead, the only other changes were the stabilizing surfaces - these were converted from aluminum to steel in order to better counterbalance the weight of the missile. Cost of the upgrade kit (warhead and stabilizers) was $1,937 in FY85, and just under 35,000 kits were made (1,460 by the Swiss, the rest by the United States).
Though it hits harder, the Mk I Mod 0 missile still has issues with speed and range - this compounds with its distinctive popping to continue putting gunners at risk. What's worse, explosive-reactive armor had begin to increase in popularity within the Soviet Union and other potential overseas enemies - something the Dragon and Dragon II had no response to.
The US Army would eventually adopt the Dragon II in 1991 as an interim solution until the results of the Advanced Anti-tank Weapon System-Medium (AAWS-M) program could be concluded - that program ultimately lead to the Javelin. These new missiles never completely replaced the original Dragons, which were largely given to training use but never the less remained in inventory right up until the end.
Super Dragon
The Super Dragon, also known as the FGM-77C, debuted in 1990 and was the final American iteration of the platform. This edition builds off of the unused "Dragon II+" (discussed below) and also seems to take cues from the "Dragon III" prototype (also discussed below). It appears to be limited entirely to the USMC, and was a wholly new missile that could not be retrofitted into an older model. I'm not sure if the missile had a new name to go with it (other than "Super Dragon" or "FGM-77C").Major improvements in range, velocity, and ability to deal with explosive-reactive armor are the main points of interest in this edition. It also appears to have marginally improved general penetrative powers, as well.
The Super Dragon is now able to send a rocket out to 2,000 meters (2187.23 yards) at a speed of around 190m/s (207.8yd/s). The warhead utilizes a spring-loaded, explosively-charged probe on the nose designed to thwart explosive-reactive armor. Owing to the increased stand-off distance (and I presume the explosive probe), this seems to have had the side effect of further improving the penetrative power to 37.4" of RHA. The actual weight and composition of the primary explosive warhead is unchanged. Overall length of the missile was probably 3.94" longer than earlier examples.
These improvements raised the weight of a complete round to 34.17 pounds, or 32.62 when in the ready-to-fire position (because the front shock absorber is kicked off when you deploy the bipod). Cost of one of these rounds is likely to have been around $7,500 in FY90 (if the Dragon III is any indication - all I have to go on right now).
The trackers were also upgraded to incorporate digital electronics, the weight of the daysight coming to 6.83 pounds, and the nightsight to 21.6 pounds (not a major change). These electronic upgrades improved a gunner's control over the rocket and evidently allowed for automatic temperature control which increased reliability to 98%.
This model was only officially adopted by the Marine Corps, though around 2001 the Super Dragon was considered for use in National Guard and Army Reserve units as an alternative to the Javelin. This never came to be.
Other Variants
The platform had a number of variants not mentioned above. These are foreign variants or examples that were not adopted or produced in large quantities.Dragon III
The Generation III Dragon or Dragon III, was planned to be an improvement over the Dragon II. In this iteration, the warhead remains largely the same, except for the inclusion of a probe meant to thwart explosive-reactive armor. The probe increases the stand-off distance by 2.16", which actually helped to further improve penetration (now reaching 37.4", a 98% improvement over the initial warhead). This couples with an improved nosecone, increasing detonation reliability to 98%.
Another major improvement lies in the flight motors, which were improved to propel the missile much further, much faster. This new variant could reach up to 1,750 meters (1,913.8 yards), though it only housed 1,500 meters (1640.4 yards) worth of controller wire. This new missile weighs 34.32 pounds, having incorporated 5.39 pounds worth of additional weight in the new motor and guidance system. Overall length of the missile increased by 3.94". These changes were significant enough that they could only be implemented as a whole new missile, and no upgrade kits were considered possible.This design was on board for USMC testing, but unfortunately was not to be - the program was called off in 1989. It would appear the basic idea, with improvements, carried on to the Super Dragon. Cost for a Generation III round was $6,700 in FY88.
Dragon II+
The Dragon II+ was a concept set up alongside the Dragon III project. While it was a given that Dragon I/II missiles could not be retrofitted to have the same or similar overall performance as a Dragon III, the Dragon II could still yet be improved in-place. To this end, the "II+" appears to have been a motor upgrade that enabled the rocket to fly at 186.4 yards (170.45 meters) per second - up from 109.4 yards (100 meters) per second. No further modifications to the missile itself appear to have been made, though that is a significant change in its own right.
Upgrades to the nightsight was also required for this iteration of the missile, but it is unclear exactly what they were.
As this was never produced in any real numbers, it appears that cost data is unavailable (or irrelevant).
Saegheh-1 and Saegheh-2
Prior to Iran's revolution in 1979, the United States provisioned the country with M47 Dragon systems. Iran appears to have reverse engineered these early models (doubtlessly the Dragon I due to the timeline involved) and produced their own copies under the name "Saegheh" ("Lightning").
I don't have access to primary (or near-primary) sources for the Saegheh. From what I can gather, however, is that the SACLOS weapon was 31.97 pounds (14.5kg) and employed a 13.45 pound (13.45 kg) rocket with a 6.84 pound (3.1 kg) warhead that could penetrate 19.685" (500mm) of RHA. The missile armed at 71 yards (65m) and reached out to 1093.6 yards (1000m).
The successor, Saegheh-2, now has a probe for defeating ERA and a larger warhead (16.315 pounds / 7.4kg). It can penetrate 24.59" (650mm), but flies at only 100.6 yd/s (92m/s). Otherwise it is much the same. This is assumed to be a new design based on the original, a copy of the Dragon I.
Much like the original, these appear to use both day and night tracking units, though any specifics are as yet unknown.
Switzerland's FGM-77D
At some point in the late 1980s, Switzerland attempted to commission an upgraded Dragon missile that incorporated a tandem warhead. This is likely an upgrade of the Dragon II, but information is extremely limited. It may not ever have actually existed off of a sheet of paper.
Mounting the M47 to the M113
The M47 Dragon can be attached to the M113 APC with the M175 mount. This mount attaches to the cupola of the APC, and provides a steady launch platform (the cupola can even be locked in place for extra security). The mount includes a cradle that accepts and firmly secures a round in place, wherein the trackers are attached as usual (though firing is done through a remote trigger closer to the rear of the tube). In addition to a stable platform, it also provides the option for a gunner to use the vehicle's power source for their nightsight tracker, in lieu of batteries. Coolant bottles will still be required, however.The mount includes a small "brush shield", designed to protect the assembled M47 on the mount when the vehicle is in motion. It has a closable loophole for viewing through the shield, and is mounted on a swinging arm so it can be moved clear of the weapon for firing. Unfortunately, I cannot find much more information about it, such as thickness or composition of the protective plating.
The M175 mount can also be removed from the M113 and interfaced with the M3 or M122 tripod using an adapter. When using a nightsight tracker, the legs of the M122 tripod will need to be sandbagged. I suspect this is a weight and balance issue.
The Weapon in GURPS
The weapon is TL7 - the technology doesn't really advance much in the strictest sense for later variants, but they are only available in TL8. It is Guided, following the rules on GURPS Basic p.412.
Damage was calculated in two steps, because we are dealing with a HEAT warhead. The penetrative part was discerned by finding a dice combination that would penetrate the nominal inches hardened steel ascribed to the warhead by at least one (without straying too far over it) - this value then gets the (10) Armor Divisor because it is HEAT (see High Tech p.170). When dealing with this many dice and multipliers, getting a combination that is dead on isn't easy - the resolution gets a bit coarse and changes to only one number result in large jumps in effect. But, hey, what's a few fractions of an inch between friends? The follow up damage portion of the weapon represents the terminal effect of the warhead's payload - this is figured out by using the guide on Explosives on B414 and is the explosion the internals are subjected to - if the warhead penetrates with the initial strike.
Damage for the Super Dragon, has one more step - that of the ERA-thwarting probe. GURPS High Tech calls this rocket type "MS-HEAT", on p.170. Since the Super Dragon can penetrate another few inches of steel than the Dragon II on account of this probe (while the warhead itself is unchanged), we can figure out the difference in penetration between the two (with and without the probe) and assign the delta to the "tandem" element of the charge. This emulates how GURPS does it mechanically and fits in line with my perception of reality-as-given (as both are added in the absence of ERA, and ERA counteract itself isn't mentioned in the penetration data I have).
Accuracy is taken straight from the entry in High Tech, as I am not entirely sure how one figures out the accuracy of a rocket. In the strictest sense it doesn't appear this particular rocket was very good, because it was evidently very responsive to input - to a fault - and actually kind of spiraled a bit towards the target. That sounds, to me, more like a skill penalty than an accuracy issue. The entry includes the bonus that magnified optics provides.
Range is taken from direct sources. This is something that appears to be consistently agreed on (probably because of how bad short was). When you think about it, that is a lot of guidance wire.
Weight is taken from direct sources (particularly the one I got the penetration stats from). Some sources seem to disagree with weight (just like every other stat). The night optic is much heavier than the day, and will require a new battery and coolant bottle for every two hours of use - they're 1.5 pounds each.
Rate of Fire (RoF) is 1 because it's a single-shot rocket.
Shots is 1, because it's a single-shot rocket. A 20 second reload time seemed reasonable, based on the videos I have seen. Indeed, it seems it can be done much faster, though those demonstrations were done in teams and may have been practiced a dozen times to reach immediacy and perfection that is not possible in the field.
Cost was an interesting one. I found references to costs in a particular article that even went so far as to cite period prices for some elements (it was focused mostly on the history of development and procurement and also gave insight into penetrative capability). Converted into the usual GURPS "2004 Dollars", that produces some pretty expensive missiles, especially as compared to the ones given in High Tech. However, the very same article also cites a $18.58 million dollar contract for 8,817 missiles in 1980 - that's only $4,794 per missile once you price-adjust it to GURPSbux.
Confusing.
The Dragon II price was actually derived from combining the Dragon I missile and the price of an upgrade package - thus it doesn't really represent a new-production missile (unclear if those really ever existed, but the capability did). Cost for the tracker - which by default is the day tracker - is lifted right from High Tech as I was unable to find a real price at the time of writing. A night-tracker, from what I've found, cost a substantial sum ($30,500 in 1978).
The night tracker is a thermal image device, following the rules for Infravision on B60. See also Thermographs on HT48.
Harsh Realism for the M47 Dragon Gunner
For those who want their gunners to suffer for their art, here's some ramblings:The weapon has issues tracking very quickly - it seems as if the tracker loses the missiles IR flare, the tracker simply sends the missile straight up to the sky. If you want to simulate this, try only permitting a single hex face change per turn while the missile is in flight. If they move more than that, the missile is automatically going to miss.
The system appears to be prone to what GURPS would simply term as "malfunctions". Trackers lose flares, wires break, users startle or twitch and the missile is wasted. From what little I have to go on as of this article's writing, it sounds like 98% reliability (in operation?) was only achieved with the Super Dragon. In GURPS that would actually be a Malf. of 16, which is already slightly low for TL7/TL8 equipment (which is assumed to be 17). If you want a twitchy weapon in your squad, you could perhaps set the Malf. of the Super Dragon to 16, and lower it to 14 or 15 for the earlier versions.
The speed for the original two versions may actually be 97.6 yards per second - I have found references to it taking 11.2 seconds to reach max distance, rather than 10. Another one of those inconsistencies that plagued this article a bit.
Accuracy may be lower than stated because the missile seems like it spirals to the target in a tight-ish cone. That could well be the difference between striking the hull and striking the turret (and so forth).
Other Considerations
Users will need to be right-eye dominant.The weapon has a roughly one second "warm up" between the trigger being pulled and the missile actually launching.
I have read that the tracker has real issues detecting the missile over bodies of water - this is possibly due to IR refraction off of the water itself resulting in loss of control of the missile. Officially, the limit is 984ft to 1312ft (300m-400m) over salt water, due to issues of short-circuiting the command wire. This is not an issue with fresh water.
The weapon has a difficult time functioning in dense woodland and urban environments - arming distances are usually further than line of sight, and the wire is at risk of damage in flight.
The guidance wire is conductive - exercise caution near power lines.
If situation forces a gunner to fire the weapon from an enclosure, official advice indicates the need for a minimum of 150 cubic feet of space, and highly recommends all doors and windows be open at the time of firing. Areas with poor ventilation may be improved by cutting 2'x2' loopholes in the walls, if possible - all these help prevent injury or death by overpressure. In addition to pressure changes, the vented gas can be toxic. Gas composition is not exactly known, so your gas mask may or may not be of use. For the effects of explosions (and backblast) in enclosed spaces, see HT181.
Indeed, it seems as if 3d backblast is actually deceptive in a sense. While that would typically greatly injure anyone hit by it, the rules for explosions in GURPS would have the effect rapidly diminish, basically making the threat only extend to 6 yards. The real weapon considers backblast out to more than five times that distance to be harmful, and considers it noteworthy for another 22 yards beyond.
Bipod and tripod fire is usually conducted sitting (bipod, tripod) or crouching (tripod), though the use of a trench or foxhole allows fire while effectively standing. If using a foxhole, ensure both ends of the weapon protrude over the trech - otherwise blast-gas may cause issues.
The integral bipod does appear to be height adjustable, allowing use kneeling as well as sitting. Travel appears to be 10", and a later manual describes it as being adjustable for users between 5' and 6'2". At the regular full deployment, the weapon system still sits fairly high off the ground, enough that a 6' former Dragon gunner described reaching around to the controls as being "awkward".
The integral bipod appears to be capable of a full 360° rotation, however when sitting it would seem as if the user has a functionally limited angle they could move through - probably no more than one hex-face left or right.
When firing the rocket prone, be sure you don't have your body in line with the tube - you will be in your own backblast. This posture is not desirable as it usually involves the weapon being very close to the ground (risk of wire damage or grounding), and does not allow the user to track a target much at all. If the launcher is less than 6" off the ground, the missile's fins will strike the deck and the missile will ground.
Regardless of posture, it is probable that the weapon would malfunction (due to the missile being unable to properly keep up with the tracker) if the user moved more than one hex-face per second (and that may well be pushing it).
Moving targets should - by advice - be moving at 21.7mph (35kph) or less for much success at destroying them. At that speed or lower, the circle around the crosshair in the sight can be used to gauge if the target will be successfully lead (by lining up the target on one side and observing that there are no obstacles within the circle).
The night tracker's cooling system makes an audible hum, which can (according to one former user) be heard within around 30' (10m).
There is a 10.4 pound inert training missile - the M223 - for firing off of an ordinary tracker; this is installed into a used tube. It uses an IR probe on a "target" vehicle to train tracking skill. An entire training and scoring system was available - these are the M54 Launch Effect Trainer and M57 Field-Handling Trainer.
A mechanized infantry squad typically is issued five batteries and five coolant bottles. A footmobile unit typically only receives three batteries and five coolant bottles.
Remember to destroy your tubes after use, lest they be used to house booby traps.
Curiously, by my calculations, even the original version of the weapon is capable of taking on the T-72A in High Tech, thwarting its front armor with reliability. Honestly, I think the main issues with this weapon are less in its penetrative capability and more in the fact that it couldn't reliably hit and detonate.
Why Not Use the GURPS Stats?
The M47 Dragon is given a place in GURPS High Tech on page 152, listed as the "FGM-77A". I already knew from basic research that there were a few variants of the platform, so I was curious as to how well the later variants compared to the one presented. One thing lead to another and I
Given that High Tech is generally well researched and does a good job of highlighting relevant variants of a given weapon system, I suspect this discrepancy is because clear and consistent data on the M47 itself and its variants isn't all that easy to come by (you should see the chaos that is my notes!). This is probably even more so when initial research was being conducted. It has long been said that the M47 had lackluster penetrative power against main-line Soviet tanks, which the entry does mention, but just how bad was not all that easily validated. While I could find plenty of "Dragon" data with a simple Google search, the bulk of it appears to be confused, intermingled between versions, or otherwise inaccurate.
This article, I hope, better compiles everything into one spot for future reference. Mind, I could be completely wrong, and the example in High Tech could be based on some sort of special insight or information I simply do not have. If more data is eventually uncovered (I was not yet able to find everything), this article will update.
(I should probably start using a Wiki...)
Closing
I wouldn't hope to present this article as a knock on High Tech or its authors, but rather an expansion on the weapon presented to us, which actually does a reasonably decent job of giving us a generic average of the different versions produced in the series. For a staggeringly vast majority of players gaming in a relevant timeline, the High Tech example would more than suffice.As long-time readers may have guessed, this weapon has relevance in my Tiberian Dawn GURPS campaign project. In it, both GDI and Nod deploy the Dragon in their infantry forces and make use of all three primary variants to varying degrees. Nod even produced their own vehicle-launched variant for their Stealth Tank (the stats for which may now be in need of improvement). Indeed, I suspect Nod (which faces far heavier tanks than GDI does) probably moves or starts to move on to something else by the end of the conflict - we'll see about that some other time.
This has been the first thing I've published in just over 5 months - just been busy and of ill motivation. Mayhaps more will come soon, and more regularly again.
Thanks for reading!
Cheers!
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