Just another day at Graf for SSG Pharris and crew, proud and happy after qualifying their Sheridan.  With a dedicated crew, all things were possible. --Robert Digerness		MBT 70 on display at Fort Knox, one of six built in the joint German - American tank development program. The vehicle featured a crew of three, an auto loader and a somewhat modified version of the same gun - launcher system as found in the Sheridan. GM was the lead US firm involved, typical of the project, agreement could not be reaches as to whether the nuts and bolts should be standard or metric size. --Gamma		View of another of the developmental models, Congress killed it with the costs out of control. The Germans applied much of what they learned from the project to Leo 1 and 2. --Gamma

Other areas unexplored; we do not know initial reactions of the East German Border Troops when the Sheridans were first seen along the trace, the gunnery experiences beyond the first major density at GTA that Terry Smith recalled or the performance of the vehicle in the early 1970s on major maneuvers. There are hundreds of troopers out there who lived these experiences, we have not found them, they have not found us.

BG (Ret) Mike O'Connel, SCO at the time of the re-flag, had no clear memory of the TO & E development or of his experiences with the M551 beyond the fact that the M114s were gone when he assumed command. It seems safe to say that the Sheridan and the cavalry got along, as crew and institutional knowledge increased, as more school trained personnel came to Europe and the maintenance echelons all across 7th Army learned the peculiarities of the vehicle, things improved somewhat.

Elsewhere, the troubled MBT 70 program was killed, so much for joint US-German cooperation in designing a new main battle tank to be fielded NATO wide, and the M60A2, everything you could want in the Sheridan and more ... pushed into a new turret and mated to the M60A1 hull, was finally fielded in both CONUS and USAREUR. Like the Sheridan, too much money had been spent on the program to kill it.

Rather than replacing existing armor battalions and swapping tanks, the A2s were added as whole new battalions to existing divisions, a good idea in Germany where tank on tank combat was the essence of battle planning. The more US tank battalions, the better everyone felt.

LTC (Ret) Lee Allen:

"The Sheridan incorporated a number of new technologies and design features that made it difficult to operate and maintain. Among these were the use of steel and aluminum components; combustible casing cannon ammunition and an electrical/mechanical gun/missile firing system."

"The hull was aluminum similar to the type used on the M-113. Mounting the engine and suspension systems to the vehicle required special bolts and fittings to compensate for the difference in the two metals. Special torque settings had to be maintained and once a little wiggle room developed the connection point would deteriorate quickly. Good crews were able to make it work."

M60A2 featuring the gun - launcher in a redesigned turret and mated to the M60A1 hull. Much of what worked well in terms of fire control with M1 was tried with the A2 ... with marginal results. Tank trivia for beers: first US tank with factory installed laser range finder, A2. First US tank with laser range finder, M551A1, after they were retro fitted in the field. --Gamma		Seen from the front, the add on laser range finder for the M551 is the box structure immediately beneath the M2 machinegun mount. The TC would slew the cupola to the target, range and then read and announce the range return from a control box to the gunner through the intercom. The gunner would then match the range line on his primary sight to the target, take his final aiming point and fire. --Hunnicut		Just inside the turret at the TC position, at left, part of the range finder to include the window where the distance return would appear as a digital readout and on right, the laser range finder sight that the TC would look through. --Hunnicut

"Keeping the vehicles running was a difficult task and required skill and perseverance of a high order. I recall one alert as Squadron Commander, in which the men of the 2nd Squadron were able to move every vehicle, including the 52 Sheridans, out of Daley Barracks. During Troop tests, in 1975 I believe, all three troops left with 18 running. E and G finished with 17 still running and F had 12, possibly because of support they had given the other two troops while they were on their tests. In contrast other troops of the regiment finished with an average of 6 vehicles. This was a real tribute to the efforts of those involved."

"Combustible casings were compensated for by the use of what appeared to be fiberglass and asbestos holding bags that covered the casings as the rounds sat in the ready rack. While with the 2nd Squadron in Vietnam I had the opportunity to see a couple Sheridans hit by RPGs. Once the combustible casings caught fire, which was almost instantaneously if they were hit, the whole vehicle exploded and burned. Because of the aluminum hull, the end result was a big puddle of molten metal on the ground and the loss of the crew."

"The firing system was what seemed like an endless series of electro/mechanical switches any one of which could shut down the whole system. It was a terribly frustrating thing to have to trouble shoot the system to locate some mechanism breaking the circuit. This was especially true in Vietnam where the heat and humidity raised havoc with the temperamental system. The ever ingenious troopers solved the problem, if you can believe it, by running a piece of WD-1, commo wire, from the electrical firing mechanism (firing pin, you might call it) to the overhead dome light. When the tank commander gave the word to fire, the loader would reach up and turn the dome light on. It worked."

"In Germany after preparing for range firing I don't recall that we had much trouble with the gun. Everything was clean and adjusted and folks were very familiar with the system. Firing the missile was another story."

"Because we didn't fire a missile very often and because the system was complex and the missiles often old and not very reliable, we set up a system on the range that greased the skids, so to speak. Before going to the missile firing point the vehicles passed through an ordnance platoon which gave them a thorough going over, tested the systems and the missiles and then sent the vehicle directly to the firing point. It worked pretty well and the crews got to see what it took to get things in order."

"During my time we had one missile load up on the vehicles just to see if we could do it. The missile were kept in storage and we ran the vehicles empty with the intention to load up if things got hot. We had been directed to turn in a large number of missiles for ordnance inspection and testing. We got permission to unpack and load up on the vehicles those that were going to be turned in. It was an interesting experience, which we taped with a portable TV and later showed to the other squadrons so they could see how it was done. A lot of bent storage racks were found as well as some which were just plain improperly fitted in the turret. It was good to get our hands on the real thing just for the experience."

"As an example of a weapons system that didn't work very well and was foisted on the troops without proper testing the Sheridan was without peer. But in the hands of motivated, smart and determined cavalrymen it was made to work."

Col (Ret) Clint Anker

"While I had worked with Sheridans at the basic course and in Vietnam, it was not until I was assigned to 2nd Squadron, 11th ACR in Germany that I really became intimately familiar with the Sheridan. I joined the squadron in September 1974 as the Squadron Border Officer and in May of 1975 I became the F Troop (Fox Troop) commander. It was here that I really got deeply involved in all facets of the Sheridan, from employment, to maintenance, to gunnery."

The system was added in the field to the Sheridan fleet. Since no additional room existed in the turret for the range finder components, the power and modulator elements (( the box shaped structures to the left and right of TC hatch )) were tacked on to the interior space of the TC ballistic shield system on top of the turret. --Hunnicut		Sheridan power pack from - 12 TM; transmission and final drives at left with cooling radiator at far right. --David C. Clarke		Engine as seen from the top with transmission at top of image. Turbo charger in center of image and " no step " plate that covered the engine governor is the white rectangle below turbo. --David C. Clarke

"The three ground cavalry troops of the squadron (all three squadrons of the Regiment) were organized with three recon platoons. Each recon platoon had one M106A1 4.2 inch mortar carrier, one M113A1 infantry squad carrier, and six M551 Sheridans. So each troop has 18 Sheridans, or a total of 54 in the squadron. All were in standard configuration, with an M2 MG at the TC's station (protected by a commander's cupola-a metal shield covering about 300 degrees around the TC, and a shield in front of the M2 that provided coverage of the remaining arc) and an M73/M73E1 or M219 7.62mm MG as a coax (the M73/M73E1 and M219 were all variants of the same gun-and none of them worked well, a true piece of junk)."

"While I was in the squadron there were two significant changes to the above. We reorganized the recon platoons, replacing the infantry squad with two scout squads. This added an additional M113A1 to each platoon. These scout squads were also fielded with the Dragon medium anti-tank guided missile. We also transitioned from the M551 to the M551A1. The A1 version of the Sheridan differed from the M551 by the addition of a laser range finder (LRF). This was, I believe, the first laser rangefinder fielded by the Army. The fielding was done two ways. About half of the squadron's Sheridans were simply swapped out for new ones with the LRF. The other half were modified on at Daley Barracks. A team showed up and did the machining and mounting for the LRF."

"The LRF was in the commander's station, and not part of the gunner's control. Nor was it slaved to the gun in any fashion. The commander would drop down to the eyepiece, push the lase button, and read the resulting range to the gunner, who then put the appropriate range line in the gunner's telescope on the target. These were not eye-safe lasers. Before any gunnery density, we had to clear the downrange area of any reflective material that might cause reflected laser energy to become a danger to people up range. This danger became apparent to me the first time we took the Sheridan to Wildflecken after conversion to the A1 configuration. While sitting on the line waiting to shoot on the first night table, I was lasing downrange to get the feel for the LRF. You could easily see the pulse of red laser light going downrange. While traversing and looking for targets at different ranges, I happened to sight a bird sitting on some perch downrange. When I tried to lase on the bird, the bird jumped when hit with the laser and flew off. Not sure if this was just coincidence, I lased several other birds, all with the same result."

"The Sheridan was an absolute nightmare from a maintenance standpoint. There were three basic systems that required maintenance-the suspension, the power train, and the turret. The suspension was by far the best component of the system and the easiest to maintain. It was rugged, reliable, and gave the system good cross country mobility. The power train was pretty good, but had some weak points. The engine was a Detroit Diesel supercharged 6V53T. 6V53T meant it was a 6 cylinder, V block, each cylinder had 53 cubic inches, and it was turbocharged. This was the same engine as the M113A1 with one change. The M113A1 was supercharged (roots type blower), while the Sheridan was both supercharged and turbocharged (exhaust gas driven turbocharger)."

The very complicated breech system of the gun - launcher. View is from the loader's position, the cannon is ready to load. --Hunnicut		View of the breech from the -12. --David C. Clarke		Big mother & little Bro --Rob Hudgins

"There were three weaknesses in the power train. First, it had a tendency to overheat in certain circumstances. Second, the transmission was not rated for the same horsepower as the engine. If drivers abruptly applied full power from a standing start, it could overstress the transmission and cause failure. The third problem related to the engine governor. The governor limited top speed, and consisted of a box mounted on top of the engine, with a control rod that mounted on top of it. The problem with the governor was that it was mounted in a position on the top of the engine were people frequently stepped on it. When the grill doors were open, there was a bar about six inches wide that ran down the center of the engine compartment. This didn't provide enough footing for some of the maintenance required. When looking for footing, people not infrequently stepped on the governor. This often resulted in a cracked top plate on the governor housing. When cracked it caused the governor to either shut down the engine entirely, or to cause the engine to run away and rev as fast as it would go."

"However, it was the turret that was the real problem. It was perhaps the worst designed turret every fielded. It may have been the worst designed system ever fielded by the US Army, period. To understand this, you have to go back to the development of the system. The shillelagh was developed independently of the Sheridan itself. The shillelagh was an infra-red guided anti-armor missile. It was six inches in diameter (roughly 152mm), stood about three feet high and weighed 62 pounds. After it was designed, the Army was looked for a platform to mount it on. The only armor system under development was the armored reconnaissance/airborne assault vehicle (ARAAV). The ARAAV was originally designed with a 76mm high velocity gun with an automatic loader. Even though the design team told the Army they could redesign the missile to fit the 105mm gun of the M60 tank (got this from then Col. Ballantyne, RCO who had worked on the project), the Army decided to fit the system to the ARAAV."

"There was a feeling that the system should not be totally reliant on a missile, and that it needed a conventional cannon capability also. Since the missile was 152mm, this meant the cannon round had to be 152mm also. With nothing in the inventory that fit this, a new round was designed. It was also decided to make this a caseless round, with no brass shell casing. This had the great advantage of not having hot shell casings rolling around the turret floor during firing, but created a number of serious problems. The simple one was how to store the rounds in the turret without creating a danger of rounds igniting by a spark (always a possibility in an electric turret). Each round came out the ammo box with a rubber cover (elephant rubber) over the powder train. The rounds were stored in the turret inside a reusable asbestos bag that covered the powder train again."

"During development, it was determined that the caseless powder train did not always burn completely when fired. When it didn't, it left glowing powder remnants in the chamber. When the next round was loaded, these glowing embers ignited the caseless powder of the incoming round, usually before the breech was closed. This was potentially fatal to the crew. To solve this problem, they created the closed breech scavenging system (CBSS). The CBSS injected a blast of high pressure air into the chamber after firing before the breech opened, clearing out any remaining embers."

Rail for Graf --Don Mowry		Sheridan in the field --Don Mowry		Me in the field --Don Mowry

"The CBSS consisted of two major components-two high pressure air bottles and a compressor that filled them. The bottles were fiberglass wound bottles that could hold up to 3100 psi of compressed air. They were inside the turret, just forward of the loader's seat. The compressor was located under the loader's seat. Unfortunately, the compressors were very unreliable. I say compressors, since there were three different models used in the Sheridan, mixed with no apparent system, so that the maintenance teams had to deal with all three within a given troop. On average, only half of the compressors were working at any one time. Each vehicle carried air hoses and those with non-functioning compressors slaved off of a vehicle that did have a working compressor."

"Of course, this meant that the receiving vehicle could only be pressurized to around 1500 psi and could not keep the pressure up during firing. A fully functioning system would engage the compressor during firing and maintain the pressure in the bottles at a full 3100 psi."

"Another problem was the extractor. When the shillelagh was fired, it left behind an aft cap. The aft cap was an aluminum casing that looked like a short shell case. It was only about a foot high and contained wires that transmitted power from the firing probe to the missile motor. To eject it from the breech required an extractor, much like a conventional shell casing in a regular breech. Unfortunately, if left engaged when using the conventional round, when the round was not fired and the breech opened, the extractor would rip open the case. This would result in powder pellets being dumped on the turret floor. To prevent this, the loader had to remember to disengage the extractor when firing conventional rounds, and to engage it when firing the shillelagh."

"To give the extractor an engaged/disengaged capability required that it be accessible from outside the breech. Thus it was bolted on to the breech on the loader's side. Since it penetrated all the way to the inside of the breech, it was subjected to the full chamber pressure when the conventional round was fired. Sometimes, this pressure would sheer the bolts holding the extractor on the breech and launch the extractor into the coax MG at high velocity, usually ripping the MG off its mount. This was relatively rare, but did occur."

"The other impact of this extractor problem was that there was no mechanical advantage to help remove an unfired conventional round from the chamber. The act of chambering the round usually wedged the round in the chamber fairly securely. If the round was not fired, or it misfired, the only way to remove the round (remember, it had a caseless powder train that provided no secure purchase to extract the projectile) was to punch it out from the front of the gun tube. So every time we went to gunnery, the bell rammer was assembled and lashed to the outside of the vehicle along the loader's side. Any stuck round required the loader to open the breech, dismount the vehicle, unfasten the bell rammer, insert it down the gun tube, and punch the round out (which the gunner had to catch inside the turret). On the M60 series, all you had to do was drop the breech and the round, aided by gravity, slid out easily."

Train moving to Graf --Don Mowry		On the range --Don Mowry		Sheridans on the range --Don Mowry

"The next major problem associated with the gun itself was what was called a rupture plug. In many armored vehicle cannon designs, the recoil system was closed. If an overpressure situation occurred, it blew the seals on the recoil system. This normally required the cannon to be dismounted from the turret to replace the seals, a very high level (usually depot) maintenance task. To alleviate this problem, the Sheridan designed into the recoil system a rupture plug. The rupture plug was a very large bolt (about an inch in diameter) that screwed into the hydraulic fluid reservoir of the recoil system. The bolt was hollow and there was a very precisely machined thickness of metal in the bolt cap that was designed to "rupture" at a specified pressure. When an overpressure situation developed in the recoil system, it caused the cap to rupture, releasing pressure and saving the recoil system seals. To fix the problem, all that was needed was to unscrew the rupture plug, screw in a new one, and fill the recoil system hydraulic reservoir. Great theory-poor execution."

"For whatever reason, the recoil system caused these plugs to rupture far more often than the M60 tank recoil system ever had problems. The entire time I was in Fox Troop, and later as the squadron motor officer, I never heard of an M60 that blew its recoil seals, but I had a rupture plug blow on my Sheridan at each of the four gunnery densities I fired as a troop commander. When the plug did blow, it released hot cheery juice (hydraulic fluid) in a fine mist that completely soaked the crew."

"But that was not all that was wrong with the gun design. The breech was an interrupted screw thread breech. It had a motor that unscrewed the breech after firing, backed it out of the chamber, and then rolled it to the right to open the chamber so the next round could be inserted. But, like many systems in the turret, it was electrically driven and power frequently failed. On the end of the breech was a small lever with a round knob handle. At the end of the handle, attached to the breech, was a key that could be pushed in to engaged the handle to the drive shaft that controlled the breech locking and unlocking. When the key was engaged, the loader could manually open and close the breech."

"Because the conventional round was caseless, it did not have a shell casing to obdurate the breech during firing. The interupputed screw thread didn't provide close enough tolerances to seal the breech, so some other sealing was needed. The solution was to use an obturator seal. The obturator seal was another finely machined piece of metal. In this case, it was a circular piece, the diameter of the breech, that press fitted into the breech and sealed the gap between the chamber itself and the breech. When in place it worked fine. But it was only a press fit and sometimes came loose when the breech was opened. To prevent this, the usual solution was to coat the obturator seal with peanut butter (I'm not making this up), press it into the breech, and then, when the gun was fired, the burnt peanut butter essentially acted as a glue that held the seal in place for subsequent firings."

"The final problem with the gun itself was the firing probe. Unlike percussion systems, where a firing pin actually struck a primer to ignite the powder train, the Sheridan had an electric firing system. The rear of the conventional round had a primer that was electrically initiated. It had metal "petals" on the primer. The firing probe at the base of the breech had a metal protrusion, about half an inch long, that penetrated the petals and made the electrical connection. When the firing circuit was energized, electricity flowed to the firing probe and then to the primer through the metal petals. The system was designed to operate at 110 volts AC. As will be explained later, the system often defaulted to 24 volts DC. And 24 volts DC was enough power to initiate firing, if everything was clean. But remember, this was caseless ammunition with no case to shield the chamber from firing residue. Every time a round was fired, some carbon was deposited on the chamber walls and the breech. It only took 2-4 rounds before the buildup of carbon on the firing probe was sufficient to cause a misfire, when the system was operating on 24 volts DC. At 110 volts AC the system would work through much more carbon fouling, but almost all of the systems were 24 volts DC. This was a real problem."

"The first time I went to gunnery, at Wildflecken, in the summer of 1975, at the end of the first day the troop had a butt full of misfired rounds. I'd not run into this problem before. At the meeting with platoon leaders and platoon sergeants that evening, I asked why we had so many misfires. PSG Stiggers, platoon sergeant for 1st platoon said it was because the loaders were not cleaning the firing probe. This was the first time I'd hear of this and asked him to explain. He said that the probes got dirty during firing and had to be cleaned after each round to ensure reliable ignition. I asked how this was done and he said ' Why using a scouring pad from the messhall, everybody knows that.' I was a bit upset at this point and allowed as how, obviously, not everyone knew this or we wouldn't have a put full of misfires. This was how I learned about this procedure. It required the loader to have a green scouring pad handy and, after every round, he reached into the breech with the pad and wiped off the firing probe. Once the word got out to everyone, the problem of misfires went away."

FTX --Don Mowry		Troop G Sheridan at GTA. --anonymous		This is a picture of my crew, the "Fireball Express". We had just come off of the line after qualifying Distinguished. This is a rare photo, as it shows the late SSG Hale (at far left, wearing the sunglasses). --John Skirmont

"Now, put this all together and the loading sequence for the poor loader would frequently look like this. Round fires (hopefully, if not see procedure above for removing stuck round). Loader engages the key in the breech drive to unlock the breech (if the electric motor was inop-but you couldn't leave the key engaged if the electric motor was working, or the spinning lever could break your arm-it wasn't all that long, but the turret was crowded) and rotates the lever vigorously many, many revolutions because the manual lever had very low mechanical advantage. He then takes the green scouring pad and wipes the firing probe (a foot inside breech). Next he checks to ensure the obturator seal is still in place. He picks up the round, removes the asbestos bag, rips the elephant rubber off the round, loads the round, and vigorously rotates the lever to close the breech."

"The last part of the turret was the electrics. Unlike the turret on the M60, which was mostly hydraulic (traverse and elevation), everything in the Sheridan was electric, except the recoil system. The missile firing system consisted of seven white boxes that contained various parts of the firing system, to include the guidance system for the missile itself. There were other boxes in the turret, most notably the accessory box and the power amplifier. Most of this system was designed to fire the missile, and adapted to firing the main gun's conventional round. But the designers of the electronics never intended these electronics to withstand the recoil generated by a 152mm cannon firing on a 17 ton chassis. This recoil wreaked havoc on the electronics, especially the accessory box and the power amplifier. The amplifier was the box that changed the 24 volt DC power to 110 AC. This was a very unreliable box. So much so, that there was an authorized modification work order (MWO) to bypass the box completely. This consisted of shunting input and output, thereby bypassing the internal electronics."

"Almost every Sheridan had this MWO applied. The "accessory box" had 10 circuit boards inside, A1 through A10. These circuit boards controlled various subsystems of the turret. A1 was the main gun firing circuit and A5 was the coax firing circuit. For some reason, the A1 card burned out frequently. The solution was to replace it with the A5 board, which was identical. When the A5 board was used in the A1 slot, it meant that the coax could not be fired by the gunner, but had to be fired by the loader. When the coax was directed by the TC, and the gunner said "on the way", the loader leaned on the trigger of the coax (assuming it would fire at all, which was not always the case with the M73/219). I had one Sheridan that had a loose lid on the accessory box. Every time the main gun fired it would cause the main gun circuit board to jump out of its slot. So, on this vehicle, part of the loaders task included pushing the circuit board in, in addition to everything he had to do (see above)."

Another great view of the night fire line as a Sheridan cuts loose. --John Skirmont		M551 crewmen uploading their Sheridan in preparation for a qualifying run. Notice the mud. The conditions could by hot and dusty one day, wet and miserable the next. --John Skirmont		Sheridans night firing from a stationary position on the firing line. The driver didn't have much to do here, and sometimes even caught up on some much needed sleep. Yes, we drivers did actually get used to the recoil enough to snooze! --John Skirmont

"I had a turret mechanic who figured out that he could solder fried circuit boards (replacements were always in short supply) and make them work. He submitted this idea through the Army suggestion program, but was told it wouldn't be pursued because they (the Army maintenance system) couldn't guarantee quality control. So a simple, cheap solution was turned down by some bureaucrat who didn't have to fight the system. We continued to solder our own."

"The other impact of recoil on the system was that it threw the calibration of the missile system off. The missile system required precise alignment to ensure hits. This required our supporting ordnance detachment, plus higher level technicians, to adjust the system each time we went to gunnery if we were going to fire the missiles. In fact the normal routine at each gunnery was to set up a calibration line with all of the tests on the Table VIII range (Table VIII was the individual crew qualification table, the only one where we fired actual missiles. We fired two missiles per vehicle each year). Just before firing, each vehicle ran through the entire missile calibration routine. The table was set up so that we always fired the two missile engagements first, before we fired any conventional main gun rounds. This was done because firing the conventional rounds frequently knocked the missile system out of calibration and no one wanted to waste a very expensive missile due to calibration problems. Of course, this begged the issue of how we would fight the Sheridan in actual combat where we wouldn't have the opportunity to run the calibration prior to the fight, and where we couldn't always fire all our missiles (each vehicle could hold eight shillelaghs in the turret) before conventional rounds were fired."

"The last issue in the turret was the coax machinegun. As already mentioned, it was very unreliable. The first version was the M73, then it was modified as the M73E1, then the M219. The M219 was not a different gun, but substantially the same as the M73 series. We had a mix of all three guns at any one time. The coax was very complex and very expensive. I was told that it cost about $5000 apiece, at a time when the M60 MG cost about $1200 apiece. The barrel mounted in a barrel jacket, which in turn was bolted into the coax tunnel in the turret. The barrel jacket contained a pair of holes into which the receiver of the MG was attached using two pins that were retracted using circular handles that resembled pins to hand grenades. The attachment did not provide a consistent, tight fit. It allowed the receiver to move on the barrel jacket, which in turn meant that rounds often jammed during feeding. Some crews resorted to taking pieces of coke cans that had been flattened and using these as shims to hold the receiver in the same position during firing. Overall, we had about 50% of the coaxes that worked, and those that worked were rotated among vehicles during tables that required coax engagements. Again, not a solution that would work in the GDP."

Nice picture of six Sheridans firing at one time. --John Skirmont		Picture shows how a TPT (Target, Practice, Tracer) round was packed in the metal shipping containers. Notice the rubber boot around the rear of the round. Because M551 rounds were fired using an electrical charge in the breach instead of a conventional firing pin, this rubber boot prevented static electricity from igniting the round. The pointed end of the "big blue" is in the foreground, covered by part of the shipping material. --John Skirmont		I was lucky enough to catch this Sheridan firing while on the move. Being a former Sheridan driver myself, I can tell you that there is a great deal of coordination required between the driver and gunner, as it was imperative that the driver keep the track moving very smooth and steady less the gunner miss the shot. Another very interesting thing about this photo is that the M551 is firing over the side. We tried to avoid this practice, as turret screens came loose and even cupola bolts sheared off as a result of the massive recoil. --John Skirmont

"The other two relatively high tech systems on the Sheridan was a stabilized gun system and the XM44 gunners sight. The XM44 was an image intensification sight for the main gun. The fact that it was the XM44 meant that it was not type classified and still considered developmental. It was notoriously unreliable. The stabilization system was not very robust, and only worked on fairly level ground. Even then, the sight picture jiggled quite a bit and while it was much better than nothing, it was not very useful going cross country. On a range road it might allow on the move firing, but only on a flat road."

"All of this resulted in a very unreliable system. During two gunnery densities in 1976 I kept detailed records of turret failures that required attention by someone outside the crew (troop or squadron turret mechanics, or ordnance detachment mechanics). Over the two firing densities, the average for the entire troop was that vehicles required outside attention an average of every 25 rounds fired. This meant that, on average, a vehicle would require outside maintenance of the turret for every basic load it fired (the basic load was 25 conventional main gun rounds-usually HEAT-MP)."

"In January of 1977 I became Squadron Motor Officer for 2/11 ACR. Now I had to worry about all 54 Sheridans in the squadron. Fortunately, I had two marvelous warrant officers to work with. Chief Warrant Officer 3 George Freisheim was the Squadron Maintenance Officer. Chief Warrant Officer 4 Bill Wilson was the commander of the Ordnance Detachment that supported the Squadron. The two were worth their weight in gold. Chief Freisheim was both a wealth of knowledge and had worked out a system to ensure high readiness rates for a notoriously unreliable system. Chief Wilson was a very senior warrant officer who seemed to know everyone in Europe in the maintenance business and could get anything he needed (or the squadron needed) if he wanted to."

Maintenance didn't stop if you were away from Daley Barracks. This picture shows me (foreground) and a member of my crew cleaning the pack (engine) and engine compartment of our Sheridan while on a border tour. --John Skirmont		Getting ready to pull the pack during maintenance week, otherwise known as Q-Service (Quarterly Service). This was normally done while we were back at the barracks, between border tours and field exercises. --John Skirmont		View from the drivers compartment of a Sheridan while on a roadmarch. I can still smell the diesel fumes when I look at this picture! --John Skirmont

"The reality was that it was impossible to maintain an acceptable readiness rate (C-1 on the Unit Status Report) if one followed the normal procedures for maintenance. The normal process was based on a prescribed load list (PLL) that was based on historical usage. A certain stock was retained on hand based on past demands. The problems were two fold. First, the repair parts system was not responsive enough to provide repair parts in the quantities required in the time required to maintain C-1. Second, we were not allowed to keep certain parts on hand because they were not repair parts, but were 'major assemblies.' The later included the XM44, the gunners telescope, and some other components. All of this was compounded by two other factors."

"First, some critical parts were in short supply and thus couldn't meet demand based PLL requirements. Second, during firing densities, the rate of breakage far exceeded the capacity of the system to respond. And yet, we (and other squadrons in Germany) managed to maintain a legitimate C-1 readiness rate, even during gunnery. This was done through a combination of working outside the normal system and a network of squadrons that shared parts. It was simply impossible to work with the normal PLL stockage."

"The result was that the squadron maintained a huge inventory of "excess" and "unauthorized" parts-most of which were turret parts. We had a turret trailer and a conex full of these parts. We had excess XM44 gunner's sights, excess gunner's telescopes, various white boxes (accessory, guidance, power amplifiers, etc.) and many, many other hard to get parts. Every time we had an Annual General Inspection we moved the trailer and the conex into the area of the artillery battalion on Daley Barracks. Discovery of these excess parts by the inspection team would have caused major problems."

"The other solution we had was an informal network of squadrons that shared parts freely. We had about four or five other squadrons we worked with. One was in the regiment, one in 2 ACR, and the rest were divisional squadrons. The rules were simple. If you called one of these squadrons for a part, and they had it, unless they had a vehicle on deadline for that part, they sent it to you. The only exception was if the unit was headed to gunnery within a week, then they kept their excess. When one of the squadrons went to gunnery, the others provided turret parts to support them. Thus, when we went to gunnery, we took not only our excess, but some of the high demand, critical items from our ' partners.'"

Sheridans secured on the hardstand. Remember the tarps? --John Skirmont		A Sheridan and an M60A1 loaded on a train in preparation for an upcoming gunnery. Due to the heavier weight of the M60A1, only one was allowed per railcar. Two Sheridans could be loaded on one car, however. --John Skirmont		M551A1's conduct tank crew training at the LTA.  I recall this location, we also used it in H Co. Across a small valley in front of the tanks, perhaps 1 kilometer away, was one of the new Bad Kissingen multi - million dollar Kur and resort hotels. The tank target ID and ranging course ran down the slope and along the valley. Thompson // Stefanowcz

"One of the items that was a perennial problem was the halon fire extinguisher. The Sheridan had a high pressure halon bottle in the turret to put out fires. If this was inoperable, the system was deadlined. The bottle had to be removed at each quarterly service and weighed to ensure it was fully charged. This was tricky because when disconnected from the vehicle it still had a lever that tripped the discharge nozzle. It was not difficult to bump this and set the bottle off. If this happened, the bottle became a rocket that could fly around and do considerable damage. To prevent this, it was possible to put a finely machined screw cap on the bottle when it was removed from the vehicle. Unfortunately, these caps were scarce (we generally had only one or two in squadron maintenance). Fire extinguishers were a constant shortage and no one had much excess to cover this, so we were exceptionally careful with these during Q services."

"I was Staff Duty Officer one weekend when I got a call from a warrant officer in 3rd Infantry Division on Sunday morning as I was about to go off duty. He asked for Chief Freisheim's phone number. I said I was George's motor officer and could I help him. He told me that he wanted George to come down and see him as he had some "parts" for him. When I called George he said this guy was a good friend and if he said it was worthwhile, it was. So George and I went down that afternoon to visit and see what he had. It turned out that he was a direct support tech supply officer with a warehouse full of parts. The unit was transitioning from DS to GS (general support) and he had to turn in all of his parts and draw a new set. Rather than turn it in, he was essentially giving it away. All we had to do was pick it up and make sure we identified the parts on his slack deck (computer punch cards). For the next two weeks we sent five ton trucks down to the warehouse to pick up parts. As part of this we picked up a huge number of Sheridan parts, to include wiring harnesses, obturator seals, and 16 complete fire extinguisher kits. These kits included bottles, wiring harnesses, and the scarce screw caps. During a subsequent AGI I found out that these kits were the entire USAREUR inventory which had been lost in transit. We turned some of them back in, but kept enough to be healthy for some time."

"Overall, the Sheridan was a mess. It was unreliable in the extreme and dangerous to the crew (turret fires were not uncommon and it was lightly armored-when hit it tended to burn to the ground in a pool of molten aluminum). It was a great day for the Blackhorse when the Sheridan was replaced with a true tank."

Robert A Stefanowicz

Fort Knox

"I was in the last Armor Officer Basic Course at Knox to feature training on the M551 as a regular part of the curriculum. Starting with the first new group of Lts arriving at Knox in January 1978, training on the Sheridan would be conducted only for those very few officers reporting to the 82nd Airborne. The M551 program was being cut back severely to reflect the direction the Army was going with the vehicle. I do not recall any of the staff stating exactly when the Sheridan would come out of inventory in Germany, just that the decision had been made."

"At Knox, training on the Sheridan lasted perhaps three or four days, split between the turret trainers and classroom instruction for Conduct of Fire and a basic familiarization with the equipment. A day of mechanical operation followed to include driving for a few hundred meters and then a tactical problem, perhaps another ½ day of driving / experience in the turret. We were always shepherded by members of the Armor School support battalion, (2/6 Cav ?), they tried to answer questions and pass on their experiences, particularly if you told the AI that you were pin pointed to a cav unit. I think we fired a round or two in day light and were fogged off the night range. As both the TC and the gunner, the round was very difficult to sense. The massive recoil rocked the tank, there was always a cloud of dust kicked and a wave of heat obscuration from the gun tube ... very difficult to track the tracer and determine with any accuracy, the strike of the round. I recall the Assistant Instructor loaded, he noted that it really was too dangerous to be around the electric breech and ammunition based on only a few hours of training."

Bad Kissingen

"Assigned to H Company in the Spring of 78, my recollections of the last days of the Sheridan with the Eaglehorse are limited to being an active observer and then participant in the training program to ready the tankers of the scout Troops to receive their new M60A1 rise/ passive tanks at a home station hand off. Six Sheridans per Troop had been placed into administrative storage, they were herded together as a group, locked and secured. Apparently, as the M551 program was ending, to ease maintenance and staffing concerns, this had been a Blackhorse policy. Anyone looking to harvest parts would do so at extreme peril."

"As Squadron Staff Duty Officer one night, the Sergeant of the Guard was SSG Pharris of Troop G. I was interested in his experiences with the Sheridan, he had been the top gun in the unit during the 1977 TCQC at GTA. As the night wore on, we ended up with the-10 TM, the Sheridan Gunnery Manual and any number of drawings made on scraps of paper spread across the desk. While I have lost much of the technical detail, I recall his enthusiasm and faith in the tank."

"From the conversation, I recall three things in specific; the M551 could be fairly trustworthy if you had an absolutely dedicated crew. There was no room for error and the TC had to consistently train and check what the gunner, loader and driver were doing. Things only worked if you followed the manuals to the letter and Pharris felt he had a great crew. He also believed that with the six tank set, the only way around the turret problems and the missile issues were to have four M551s only fire the main gun in the event of war and the other two Sheridans would only fire the missile. That way, as missile components failed, your could scavenge within the platoon, you could arrange your gunners based on who did what best and the requirement of constantly checking the missile alignment system was reduced to 1/3 of the platoon. His last point that I remember related to using the standard gunner's reticle to engage a moving target coming toward you at an angle.

My crew on the firing line, WTA, 77. --Dan Thompson		The Sheridans were exchanged for M60A1 r/p ' s at the BK Bahnhof  in the early Summer of 78. A brand new E Troop tank waits to fit on to the Camp Lee hardstand. --Dan Thompson

' Now that gunner has this complicated reticle based on range lines, ammunition type, aiming points, lead lines based on estimated speed ... it all was set up for a shot at a 90 degree angle. When you add in the target is coming towards you but at an angle, the gunner is really on his own as to where to place the aiming point. It's all explained in the manual but, damn, who can remember all those steps in combat?! But my gunner could 'cause he's got PFM ... pure f******g magic!'"

"As the plan to replace the Sheridans was published, H Company was heavily tasked to provide home station training for the Eaglehorse Sheridan personnel. I recall the training was done Troop by Troop, on a staggered rotational basis. It included familiarization and mechanical training on the hard stand, class room training and then driver and gunner training in the LTA. The program of instruction came from the squadron S3 shop and was based on the emerging Skill Qualification Training system for 19E personnel. For some of the 19G crewmen, it was a difficult transition, particularly the skills required to lay the gun to the target and then get to the range finder and range to the target. Also, it seemed as though the cavalry Troops had priority for arriving 19E NCOs to insure that each unit also had at least a few experienced tankers."

"Training in the LTA consisted of a TCQC course set up in the valley that ran the length of the area, perhaps five of six mock engagements, none at a range beyond 1200 meters because of the limited size of the area. The H Co NCOs, hooked in their CVCs to a split harness allowing them to monitor and instruct the crews and then held on for dear life to the turret-bustle rack as the tanks went through the course. At the end of the training day, they would debrief and then dismiss the cav Troop tankers and then howl over what they had seen. But, having said this, progress occurred and using the 19E Skill Manual as the training guide, good progress was made."

"The actual tank exchange was done on one of those rare hot late Spring days in Germany. A DS unit from Hanau or Frankfurt was to receive the Sheridans and it was a very forgiving program. Basically, the M551 needed to move to the Bad Kissingen Bahnhoff under its own power to be accepted. The vast quantities of special tools, ground hop kits, diagnostic equipment and hidden spare parts were loaded into the turrets and off they marched, one Troop at a time. Word filtered back to Daley that some consternation occurred when an M551 got to the rail head but couldn't limp on to the flat car ... would the DS unit accept that tank? Apparently, the answer was yes, it was to everyone's interest to get through the day and by 17 00, the only tanks remaining at Daley Barracks were the 17 M60A1s of HAWG Company."

"A guard force was configured to remain by the loaded train and it departed early the following morning. (that was a photo missed !) An hour later, the second train arrived, thirty-six new (or re-manufactured) M60A1s. The tanks were road marched back to Daley, older German citizens of BK probably moaned that the cavalry had gone back to only the big tanks that made big noise. Later that day, an around the clock consolidated painting program began to get the new arrivals into the proper scheme and within a week we were at WTA. Months later, as Squadron Motor Officer, I was still running a weekly truck to Frankfurt to hand off Sheridan parts and equipment that kept rolling out of CONEXs, lockers and maintenance trucks. The Eaglehorse would not see the Sheridan again for fifteen years."