Replies

Much debate has ensued over what the future of the M1 Abrams tank should be. Many have bought into the notion that the tank is dead. Others feel we should convert existing Abrams to improve its overall capabilities. What is universally accepted is that the existing Abrams has significant problems that must be addressed.

One of the low-rate-initial-production (LRIP) M1 tanks at Aberdeen Proving Grounds right after introduction into service. This tank is painted in the old MERDC cammo scheme.

I think a lot of proposals for the Abrams are to convert it to perform roles that are really better suited to a medium tank based on the Bradley. At its core, the Abrams is a tank destroyer and there is still a place within the force for this capability. Missiles can be countered too easily to use them as the sole method of dealing with heavy armor enemies. But there need to be significant improvements in the overall capabilities of the Abrams.

The Engine Question

From the day the Abrams was created, there has been extensive arguments over the value of the turbine engine instead of a conventional diesel engine. A number of myths need to be addressed here. While the Abrams uses massive quantities of fuel, so do all other heavy tanks. The biggest difference is in how they are used. The British Challenger 2 is rated at about three gallons per mile in cross country operations and this uses a conventional diesel engine. Where there IS a major difference is when the engine is at idle but this problem can be compensated for by using auxillary power units. While the current Abrams powertrain consumes a lot of the Army's maintenance budget, this is largely because of the excessive size of the Abrams force and the age of the powertrains. The current Abrams engine uses 1960s technology and the U.S. currently maintains a fleet of around 8000 Abrams tanks. At the most, only 2000 of these tanks could EVER be put to use.

One of the first M1 Abrams tanks.

The turbine engine offers a number of significant advantages that should not be so easily dismissed. The first is that a turbine engine generally doesn't care what kind of fuel is being used. Whether it is the kerosene-type diesel the U.S. uses or standard diesel purchased locally abroad, the turbine can burn any of it with no real problems.

There is also the issue of smoke, particularly in cold weather. Conventional diesels put out enormous quantities of smoke when started, especially in cold weather. Turbines don't have this trait - they are smokeless engines regardless of conditions. Noise is another important factor that must be addressed. The turbine engine produces substantially lower noise than conventional diesels. These are important signatures being eliminated by using turbines.

M1A1 with Mine Plough.

Personally, I place these advantages as being of greater importance than the negatives associated with the turbines. One of the arguments used for conventional engines is to allow soldiers to follow the tank but with the size and weight of the Abrams, it isn't necessarily suitable in this role. There's also the issue of the blast from the Abrams 120mm cannon - do we really want infantry operating THAT close to this tank? If not (and I think there are better systems like the Assault Gun Mortar and Bradley Medium Tank for these roles) then I think we should keep the turbines in the Abrams. Most enemy don't possess thermal sights but they all have eyes and ears and the turbine makes the tank far less susceptible to these.

Armament

Tank armament is always an iffy thing but the real problem the Abrams has (that few people recognize) is that it can burn up ammo way too fast for the amount of ammunition it can hold. At the heart of this problem is the fact that the Abrams lacks an effective mid-size gun in its secondary armament. If a given target is anything that cannot be taken out by a .50 caliber machine gun, the only option available is the main gun. Moreover, there is no ammunition available for the main gun for any role other than anti-tank. So we need to make a number of changes here.

First is to develop an Abrams round that can accept 105mm semi-fixed artillery shells. This would dramatically improve the options available for using the main gun without having to go through all kinds of problems with developing and manufacturing new rounds. We will still only be able to carry 40 rounds of ammunition, but improved secondary armament can help this problem.

The Russian BMP-3 uses a 30mm auto-cannon for its secondary armament and looks like the best option for the Abrams as well. The 30mm offers excellent range and lethality and is readily available as it is used in a variety of systems already, including the AH-64 Apache. If we develop a round similar to the Bofors 40mm AP-3 round, we can effectively use this secondary gun against virtually any target.

Since the primary purpose of the ring mounts on the turret are for engaging nearby personnel threats, I would replace the commander's .50 caliber machine gun with the 30mm cannon mounted in a cupola like that of the M-60 tank. The loader's gun should continue to be the 7.62mm machine gun to give the tank a good mix of explosive and direct fires at close range.

We should also replace the standard smoke grenade arrangement with a breach loaded rack that could hold disposable grenade launchers. This would give us the ability to use these mounts for a variety of roles including smoke, marking, anti-personnel, and flame.

Protection

The two systems that should be added for improved protection are command-detonated Explosive Reactive Armor and the anti-RPG force field system currently in development. The most prevalent anti-tank weapon in the world is the RPG so the inclusion of this system is a no-brainer. This is also an effective anti-missile system as most anti-tank missiles rely on the shaped charges these force fields are designed to defeat.

A mine plow-equipped M1A2 Abrams explodes a mine while clearing a safe lane.

CDERA can be effective in two roles. First is that it can serve as ERA to defeat most types of anti-tank munitions. Including the command detonation option allows the tank to serve as a rolling mount for anti-personnel mines. In close engagements, the ERA tiles can be detonated to devastate nearby enemy. In the future, sensors can be added to the system to allow for an active defense system at stand-off ranges.

Many call for the use of roofs on tanks in order to detonate top attack weapons at a stand-off distance from the tank and also to provide some cover for those using the secondary armaments. I think all tanks should have this capability, but it shouldn't be a permanent install as there are a number of situations where these roofs could pose a problem

Scott Miller

Further discussions with others on this topic gives me the impression that regardless of what I personallly believe about the Abrams, many WANT a diesel engine in this tank. Regardless of it's weight and size issues, many combat arms folks want to use the Abrams in defensive and infantry support roles. While I do not support this idea, I feel obligated to share the knowledge I have of this issue so that if we DO decide to field a diesel version of the Abrams, then we do it properly.

A really impressive picture of a M1A2 SEP firing at night.

Because of the tremendous weight of the Abrams, it is not well suited to a hybrid powertrain although the Allison parallel hybrid may be a potential option. Still, the notion of using batteries to power a tank may not be a particularly good idea as batteries tend to be awfully volatile in this usage where the vehicle is going to be getting pounded with explosives and kinetic energy projectiles regularly. Realistically, at this stage of man's technological development, we should still be using mechanical powertrains for tanks.

Contrary to popular belief, putting a 1500hp diesel engine is NOT going to yield significant gains in fuel consumption in and of itself (in cross country operations, the diesel British Challenger 2 and German Leopard are both rated at between 2 and 3 gallons of fuel per mile traveled which is around the average for the Abrams according to most sources). The problem with Abrams fuel consumption is not the engine, it is how the tank is currently used. You have to match up the appropriate powertrain for the role of the vehicle. As a rule of thumb:

Lots of idle time in a defensive posture is better suited to a diesel but is best suited to an APU which will burn the same amount of fuel in a day that an idling diesel will burn in an hour. For those who doubt this, consider the Russian T-90 tank - it is essentially a T-80 tank with a diesel replacing the turbine engine but they still put in an APU because of excessive idle fuel consumption. A large tank diesel can burn well over 5 gallons per hour at idle; better than the turbine but still an enormous amount of fuel for a vehicle that isn't moving.
Lots of stop and go at modest top speeds is slightly better suited to the turbine because of its bottom end torque from continuous combustion. You also don't get the smoke and noise of acceleration as with a diesel. The key here is that the tank is doing a lot of wide open acceleration, a role that is better suited to turbines as this is how they are designed to operate.
For relatively constant low speed driving, as with combat patrols and overwatch roles, you're better off with a diesel because you can save a considerable amount of fuel here and this is the sort of role in which diesels really excell - steady speeds.
For high constant speeds, the advantage kicks back to the turbine as diesels don't like running at max RPMs for considerable lengths of time whereas the turbine thrives on this. You may get slightly less fuel consumption, but this will be more than offset by maintenance costs and the turbine will have far less in this role. Many get confused here as civilian semi-trucks use conventional diesels and are cruising at 60mph with massive weight - what they fail to grasp is that these trucks typically have 13 to 18 forward gears to assist the engine in getting to that speed and maintaining; the Abrams currently has only 4 forward speeds and I haven't seen a tank transmission yet with more than 6 forward speeds.

An Abrams M1A1 on the firing range at Yakima

Now then, where we have a problem today is that current Army doctrine is for cavalry type operations that tend to fall into categories 2 and 4, which means the Abrams should use a turbine based upon our current doctrine. On the other hand, modern warfare and most future conflicts are likely to focus more on operations that fall into categories 1 and 3 which leads us to a diesel conclusion. Unfortunately, many within the pro-diesel community just go with the idea that if we throw a big diesel in the Abrams, we can use it for ALL roles and achieve significant gains in fuel consumption. Keeping the high power levels will inevitably result in continued "lead footing" in the armor community, which is the REAL source of our excessive consumption of fuel. The problem isn't the engine - it is our practice of blasting across the countryside at 40mph+ when we don't need to and really shouldn't.

Since the entire reason people desire a shift to a diesel is to make the Abrams better for urban and infantry support roles, the obvious solution is to take the ability to fly about the countryside away from the Abrams. These intended roles do not need the ultra high power levels, and to be frank, the Abrams would be better in these roles WITHOUT the high power. A smaller diesel may sacrifice some acceleration but you make tremendous gains in fuel consumption and reliability. The key here is to downsize the engine in the transition. What I propose is to outfit the Abrams with a 900hp diesel for this application.

At 900hp, this Urban Abrams would still have a better power-to-weight ratio than the old M-60s (and most of the tanks used by nations we consider enemies) but it generally will use 40-50% less fuel than the larger diesel in this application, which translates into a very significant improvement of the turbine. The tank would still be capable of significant speeds that are adequate for most combat situations but it takes away the current ability to blast across the countryside, hence we will save additional fuel from ending this wasteful action in and of itself. Ideally, we could also add a "road gear" that would enable the tank to cruise at higher speeds on hard roads for long range transport without using tank transporters (the British Challenger 2 uses a total of 6 forward speeds with a 1200hp engine so there is really no obstacle to adding gears for on-road operations). The smaller diesel will give us the REAL gains in fuel consumption that many people desire.

To address the other half of the combustibles equation, I propose we do a crash development on a new gun that will use existing ammunition in a new way. As outlined in my article on Abrams ammunition, 105mm semi-fixed artillery ammunition comes in a lot of useful flavors for this particular application. With the greatly reduced fuel consumption of the small diesel engine, we won't need 498 gallons of fuel storage on this tank. Recent advances have been made using liquid propellants in guns that are not volatile when hit by enemy fire but are still very effective as propellants. The downside is that this application requires an autoloader to manage the propellant. But what about a semi-automatic gun?

Instead of a fully autoloading system, why not use a manually-fed autoloader? The loader would simply be loading the "autoloader" one round at a time with the actual feeding into the gun and injection of propellant being automated. If we design this system to use the 105mm projectiles, we gain a number of advantages with this design. For starters, we retain the manual loader and the flexibility of choosing specific rounds at will. Second, we can fit will over 100 rounds in the existing ammunition storage boxes of the Abrams while the propellant would be stored in modified tanks replacing the unneeded fuel storage, so we aren't losing space or survivability. Third is that without using the long tank rounds, we can increase the elevation of the main gun to heights more useful for this application, making the Abrams an artillery piece as well as a tank.

And finally a far greater variety of ammunition would be available as the rifled 105mm artillery barrel is already compatible with all existing 105mm rounds but could also be used to fire HESH rounds, laser-guided rounds like the Russian Refleks, and dedicated anti-tank rounds like the British CHARM system. And realistically, we may be able to carry a total in excess of 120 main gun rounds in this configuration so we can carry significant quantities of a wide variety of ammunition. Plus the 105mm gun would be lighter in weight to boot - this will likely offset the gain in weight from switching to a diesel engine.

Personally, I still think a Bradley Medium Tank is better suited to this role, but since many in the combat arms community desire a diesel variant of the Abrams, this is probably the best approach to take. Use a smaller diesel engine to maximize our gains in fuel consumption and convert the main gun to a semi-automatic 105mm howitzer that uses liquid propellant with existing artillery projectiles. Throw in the 30mm cannons mentioned above and replace the existing built-in grenade launchers with breech loaded disposables and this should be an extremely potent platform. We'll end up with a much more reliable and cost effective system that should also be far more useful in the types of combat roles expected in the future.

Scott Miller

Additional Sources:

www.fas.org
www.geocities.com/dominantlogistics
www.fprado.com
www.jodyharmon.com
softland.com.p
www.friedberg.org
www.arms.ru

On this day In History

Birthdates which occurred on January 13:
1381 St Colette abbess/reformer (Poor Clares)
1596 Jan J Goyen Dutch landscape painter
1616 Antoinette Bourignon Flemish mystic/French religious fanatic
1628 Charles Perrault France, lawyer/writer (Mother Goose)
1778 Anton Fischer composer
1807 Napoleon Bonaparte Buford Major General (Union volunteers), died in 1883
1808 Salmon P Chase (Senator-R) cabinet member, 6th chief justice (1864-73)
1812 Humphrey Marshall Brigadier General (Confederate Army), died in 1872
1834 Horatio Alger Jr Revere MA, author (Lost at Sea, Work & Win)
1864 Wilhelm K W Wien German phyicist (Nobel 1911)
1884 Sophie Tucker [Kalish], Russia, singer/last of red hot mammas
1885 Alfred Fuller CEO (Fuller Brush Man)
1909 Danny Barker jazz guitarist
1913 Ralph Edwards Merino CO, TV host (This is Your Life)
1919 Army Archerd Hollywood columnist/TV host (Movie Game)
1919 Robert Stack Los Angeles CA, actor (Eliot Ness-Untouchables, Airplane, Unsolved Mysteries)
1925 Gwen Verdon Louisiana, actress/singer/dancer (Cotton Club, Sweet Charity)
1931 Charles Nelson Reilly New York City NY, actor (Match Game, Ghost & Mrs Muir)
1934 Rip Taylor comedian (Gong Show, $1.98 Beauty Show)
1938 Billy Gray Los Angeles CA, actor (Bud-Father Knows Best)
1943 Richard Moll California, actor (Night Court, House, Dungeonmaster, Survivor)
1945 [Eileen] Joy[ce] Chant [Rutter] UK, sci-fi author (High Kings)
1948 T Bone' Burnett rocker
1949 Brandon Tartikoff TV exec (NBC)
1961 Julia Louis-Dreyfus New York City NY, comedienne (SNL, Seinfeld)
1966 Tabitha Stevens fictional character (Bewitched)

Deaths which occurred on January 13:
0533 Remigius van Reims 1st bishop of Reims (459-533)/saint, dies about 96
0858 Aethelwolf king of Wessex (Battle at Aclea), dies
0888 Charles III the Fat One, King of Franconia/Roman emperor, dies
1599 Edmund Spenser poet (Faerie Queene), dies at about 46
1691 George Fox founder of Quakers, dies at 66
1864 Stephen Foster composer (My Old Kentucky Home), dies in a New York hospital at 37
1879 WF Hendrik the Navigator prince of Netherlands/viceroy of Luxembourg, dies at 58
1929 Wyatt Earp US marshall (OK Corral), dies at 80
1941 James Joyce novelist (Ulysses), dies in Zürich Switzerland, at 58
1968 Bill Masterson (Minnesota Northstars) checked into the boards & killed
1978 Hubert Humphrey (Senator-D-MN, Vice President), dies at 66 in Waverly MN
1985 Carol Wayne Johnny Carson's teatime movie hostess, dies at 42
1986 Abdel Fattah Ismail President of South-Yemen (1969-80), murdered
1988 Chiang Ching-kuo President of Taiwan (1978-88), dies at 81

Reported: MISSING in ACTION

1961 DUFFY CHARLES J.
1967 CRONIN MICHAEL P.---PITTSBURGH PA.
[03/04/73 RELEASED BY DRV, ALIVE IN 96]
1967 TURLEY MORVAN DARRELL---KANSAS CITY MO.
[10/12/67 REMAINS RECOVERED]
1969 EATON NORMAN D.---WEATHERFORD OK.

POW / MIA Data & Bios supplied by
the P.O.W. NETWORK. Skidmore, MO. USA.

On this day...
1099 Crusaders set fire to Mara Syria
1559 Elizabeth I crowned queen of England in Westminster Abbey
1610 Galileo Galilei discovers Callisto, 4th satellite of Jupiter
1630 Patent to Plymouth Colony issued
1695 Jonathan Swift ordained an Anglican priest in Ireland
1733 James Oglethorpe & 130 English colonists arrive at Charleston, SC
1794 Congress changes US flag to 15 stars & 15 stripes
1830 Great fire in New Orleans thought to be set by rebel slaves
1849 Vancouver Island granted to Hudson's Bay Co
1854 Anthony Foss patents the accordion
1863 Thomas Crapper pioneers one-piece pedestal flushing toilet
1869 Colored National Labor Union, 1st Black labor convention
1873 PBS Pinchback relinquishes office at Louisiana Governor
1874 Battle between jobless & police in New York City NY, 100s injured
1874 US troops land in Honolulu to "protect" the king
1882 Richard Wagner completes his opera "Parsifal"
1888 National Geographic Society founded (Washington DC)
1898 Emile Zola publishes his open letter (J'accuse) in defense of Captain Alfred Dreyfus in Paris
1906 1st radio set advertised (Telimco for $7.50 in Scientific American) claimed to receive signals up to one mile
1910 JM Synge's "Deirdre of the Sorrows" premieres in Dublin
1915 Earthquake in Avezzano Italy kills 30,000
1915 W Churchill presents plan for assault on Dardanelles
1929 Humanist Society established, Hollywood CA
1935 Plebiscite in Saar, indicates a desire (90.3%) to join Nazi Germany
1942 Henry Ford patents a method of constructing plastic auto bodies
1943 British Prime Minister Winston Churchill arrives in Casablanca
1943 Hitler declares "Total War"
1943 Russian offensive at Don under General Golikov
1943 US infantry captures Galloping Horse-ridge Guadalcanal
1948 1st country music TV show, Midwestern Hayride, premieres on WLW Cincinnati OH
1951 9 Jewish Kremlin physicians "exposed" as British/US agents; known as the Doctors' Plot
1953 Marshal Josip Tito chosen president of Yugoslavia
1957 Wham-O Company produces the 1st Frisbee
1958 9,000 scientists of 43 nations petition UN for nuclear test ban
1958 US newspaper "Daily Worker" ceases publication
1959 De Gaulle grants amnesty to 130 to Algerian death row convicts
1959 King Boudouin promises Belgian Congo independence
1962 Wilt Chamberlain of Philadelphia Warriors scores NBA-record 73 points vs Chicago
1964 Karol Wojtyla(Pope John PaulII) becomes archbishop of Krakow
1966 1st black selected for Presidential cabinet (LBJ selects Robert C Weaver-HUD)
1968 Beginning of Tet-offensive in Vietnam
1968 Minnesota North Stars center Bill Masterton fatally injured (dies on 15th)
1969 Beatles release "Yellow Submarine" album
1979 Charlie Daniels hosts the Volunteer Jam
1979 YMCA files libel suit against Village People's YMCA song
1980 Head of narcotic brigade arrested for drug smuggling in Belgium
1982 Air Florida 737 took off in a snowstorm, crashes into the 14th St Bridge in Washington, DC, & falls into the Potomac River, killing 78
1982 Hank Aaron & Frank Robinson elected to Hall of Fame
1984 TV anchor Christine Craft wins $325,000 in her case against KMBC-TV
1987 7 top New York Mafia bosses sentenced to 100 years in prison each
1987 W German police arrest Mohammed Ali Hamadi, suspect in 1985 hijacking
1988 Supreme Court rules (5-3) public school officials have broad powers to censor school newspapers, plays & other expressive activities
1989 Ruins of Mashkan-shapir (occupied 2050-1720 BC) found in Iraq
1989 Subway gunman Bernhard Goetz begins 1-year jail sentence
1989 Computers across Britain hit by "Friday the 13th" virus
1990 1st elected US black governor inaugurated (Douglas Wilder-Virginia)
1991 UN Secretary General Javier Perez de Cuellar meets with Saddam Hussein in Baghdad
1992 US serial killer Jeffrey Dahmer pleads guilty but insane

Holidays
Note: Some Holidays are only applicable on a given "day of the week"

Ghana : Redemption Day (1972)
Togo : Liberation Day (1963)
US : Stephen Foster Memorial Day
US : What You Don't Know Day
US : Man Watcher's Week (Day 3)
National Soup Month

Religious Observances
Christ-Sweden/Norway : Tyvendedagen/St Knute/20th day of Christmas
old Roman Catholic : Feast of the Baptism of Jesus
Roman Catholic : Feast of Blessed Yvette
Roman Catholic : Feast of St Leontius
Christian : Feast of Hilary, Bishop of Poitiers
Roman Catholic, Anglican : Memorial of St Hilary, bishop of Poitiers/doctor (opt)
Lutheran : Commemoration of George Fox, renewer of society

Religious History
1501 The world's first hymnbook printed in the vernacular was published in Prague. It contained 89 hymns in the Czech language. (The name of the hymnal is no longer known, since the only surviving copy lacks the title page.)
1635 Birth of Philip Jacob Spener, founder of German pietism. The name for the Bible studies (called "collegia pietatis") held in his home came to be associated with his followers, who were afterward called Pietists.
1691 Death of George Fox, 67, English founder of the Society of Friends (Quakers). Fox left the Anglican church at 23 and founded the Quaker movement in 1660 at age 36.
1936 Baptist clergyman B.B. McKinney, 50, wrote the words and tune to the gospel song, "Wherever He Leads, I'll Go," a few days before the opening of a Sunday School convention in Alabama.
1974 A Gallup poll on religious worship showed that fewer Protestants and Roman Catholics were attending weekly services than ten years earlier, but that attendance at Jewish worship services had increased over the same period.

Source: William D. Blake. ALMANAC OF THE CHRISTIAN CHURCH. Minneapolis: Bethany House, 1987.

Thought for the day :
"The best way to keep children home is to make the home atmosphere pleasant--and let the air out of the tires."

Question of the day...
How can someone "draw a blank"?

Murphys Law of the day...(Katz's Law)
Men and nations will act rationally when all other possibilities have been exhausted.

Astounding fact #89,240...
Advertisements for coffee in London in 1657 claimed that the beverage was a cure for scurvy, gout and other ills.

'Something' felled an M1A1 Abrams tank in Iraq – but what?

by John Roos, Army Times [US] October 27th, 2003

Mystery behind Aug. 28 incident puzzles Army officials

Shortly before dawn on Aug. 28, an M1A1 Abrams tank on routine patrol in Baghdad “was hit by something” that crippled the 69-ton behemoth.

Army officials still are puzzling over what that “something” was.

According to an unclassified Army report, the mystery projectile punched through the vehicle’s skirt and drilled a pencil-sized hole through the hull. The hole was so small that “my little finger will not go into it,” the report’s author noted.

The “something” continued into the crew compartment, where it passed through the gunner’s seatback, grazed the kidney area of the gunner’s flak jacket and finally came to rest after boring a hole 1½ to 2 inches deep in the hull on the far side of the tank.

As it passed through the interior, it hit enough critical components to knock the tank out of action. That made the tank one of only two Abrams disabled by enemy fire during the Iraq war and one of only a handful of “mobility kills” since they first rumbled onto the scene 20 years ago. The other Abrams knocked out this year in Iraq was hit by an RPG-7, a rocket-propelled grenade.

Experts believe whatever it is that knocked out the tank in August was not an RPG-7 but most likely something new — and that worries tank drivers.

Mystery and anxiety

Terry Hughes is a technical representative from Rock Island Arsenal, Ill., who examined the tank in Baghdad and wrote the report.

In the sort of excited language seldom included in official Army documents, he said, “The unit is very anxious to have this ‘SOMETHING’ identified. It seems clear that a penetrator of a yellow molten metal is what caused the damage, but what weapon fires such a round and precisely what sort of round is it? The bad guys are using something unknown and the guys facing it want very much to know what it is and how they can defend themselves.”

Nevertheless, the Abrams continues its record of providing extraordinary crew protection. The four-man crew suffered only minor injuries in the attack. The tank commander received “minor shrapnel wounds to the legs and arms and the gunner got some in his arm” as a result of the attack, according to the report.

Whatever penetrated the tank created enough heat inside the hull to activate the vehicle’s Halon firefighting gear, which probably prevented more serious injuries to the crew.

The soldiers of 2nd Battalion, 70th Armor Regiment, 1st Armor Division who were targets of the attack weren’t the only ones wondering what damaged their 69-ton tank.

Hughes also was puzzled. “Can someone tell us?” he wrote. “If not, can we get an expert on foreign munitions over here to examine this vehicle before repairs are begun? Please respond quickly.”

His report went to the office of the combat systems program manager at the U.S. Army Tank-automotive and Armaments Command in Warren, Mich. A command spokesman said he could provide no information about the incident.

“The information is sensitive,” he said. “It looks like [members of the program manager’s office] are not going to release any information right now.”

While it’s impossible to determine what caused the damage without actually examining the tank, some conclusions can be drawn from photos that accompanied the incident report. Those photos show a pencil-size penetration hole through the tank body, but very little sign of the distinctive damage — called spalling — that typically occurs on the inside surface after a hollow- or shaped-charge warhead from an anti-tank weapon burns its way through armor.

Spalling results when an armor penetrator pushes a stream of molten metal ahead of it as it bores through an armored vehicle’s protective skin.

“It’s a real strange impact,” said a source who has worked both as a tank designer and as an anti-tank weapons engineer. “This is a new one. … It almost definitely is a hollow-charge warhead of some sort, but probably not an RPG-7” anti-tank rocket-propelled grenade.

The well-known RPG-7 has been the scourge of lightly armored vehicles since its introduction more than 40 years ago. Its hollow-charge warhead easily could punch through an M1’s skirt and the relatively thin armor of its armpit joint, the area above the tracks and beneath the deck on which the turret sits, just where the mystery round hit the tank.

An RPG-7 can penetrate about 12 inches of steel — a thickness far greater than the armor that was penetrated on the tank in Baghdad. But the limited spalling evident in the photos accompanying the incident report all but rules out the RPG-7 as the culprit, experts say.

Limited spalling is a telltale characteristic of Western-manufactured weapons designed to defeat armor with a cohesive jet stream of molten metal. In contrast, RPG-7s typically produce a fragmented jet spray.

The incident is so sensitive that most experts in the field would talk only on the condition that they not be identified.

One armor expert at Fort Knox, Ky., suggested the tank may have been hit by an updated RPG. About 15 years ago, Russian scientists created tandem-warhead anti-tank-grenades designed to defeat reactive armor. The new round, a PG-7VR, can be fired from an RPG-7V launcher and might have left the unusual signature on the tank.

In addition, the Russians have developed an improved weapon, the RPG-22. These and perhaps even newer variants have been used against American forces in Afghanistan. It is believed U.S. troops seized some that have been returned to the United States for testing, but scant details about their effects and “fingerprints” are available.

Still another possibility is a retrofitted warhead for the RPG system being developed by a Swiss manufacturer.

At this time, it appears most likely that an RPG-22 or some other improved variant of the Russian-designed weapon damaged the M1 tank, sources concluded. The damage certainly was caused by some sort of shaped-charge or hollow-charge warhead, and the cohesive nature of the destructive jet suggests a more effective weapon than a fragmented-jet RPG-7.

A spokesman for General Dynamics Land Systems, which manufactures the Abrams, said company engineers agree some type of RPG probably caused the damage. After checking with them, the spokesman delivered the manufacturer’s verdict: The tank was hit by “a ‘golden’ RPG” — an extremely lucky shot.

In the end, a civilian weapons expert said, “I hope it was a lucky shot and we are not part of someone’s test program. Being a live target is no fun.”

Before deploying many said "You know, the LEO is a good tank too." Now- NO ONE wants to ride on anything but an M1A1 HA.

There have been M1s hit with RPGs (7,9 and 13) as much as 15 times and the crew walking away untouched. Except for ONE case where two crewmembers were killed in an event that would have resulted in the same (Probably worse) outcome regaudless of the tank, NO one was killed under armor in an M1. All were either name tape defilade, open protected or in some way exposed when shot or hit with an IED.

The M1 in its SEP version is UNMATCHED in firepower, mobility and survivability as an offensive tank. NOTHING, absolutely NOTHING keeps up with this machine. Joe, being spoiled always bad mouths his equipment but often has no idea of what he's got.

When matching advantages and disadvantages of the turbine, concider this in addition to what you said:

Turbine don't care if it's 145F outside, the diesel does!

Turbine starts easy in the cold.

Turbine is smaller and lighter, freeing up volume and weight for other things.

Turbine is MORE reliable than a complex high output diesel. Those diesels in tanks are like racing car engines. They squeeze as much as they can out of the smallest volume and weight. Two turbos, fuel injection, 4 valves per cylinder, 12 cylinders, electronic engine management- It's not a John Deer tracktor engine. But it's still cheaper than a turbine!

You can jumpstart a turbine with a HMMWV, needs little power to spin up. Forget turning over a 47 liter high compression diesel.

Turbine is quieter and can't be heard as far away.

FUEL CONSUMPTION ON AN M1 AT 20MPH IS 1MILE PER GALLON (Constant speed). It's actually better than a diesel. Even in the defense we fight a MOBILE defense. A stationary tank is a dead tank, even an M1. That's with a engine that may have been rebuilt 3 times has not been built for about 16 years and is a design from the 60s. And it still beats out NEW diesel designs in actual milage on the move or with a plow (under load). Also remember that JP-8 which we burn has less power per volume. Diesel contains more energy per liter or gallon. The M1 is also nearly 7 metric tonnes heavier than a LEO. So when these idiots do their stupid comparisons in some chat room- remember fuel and weight ALSO play a factor.

Integrated into the turbine is a cool air system and NBC system. Completely seperate systems on Diesel tanks, which requires more volume and weight.

A turbine not only smokes less at start up, but the turbine produces less soot which is very visible on the diesel tanks with the Thermals.

Unlimited power. Yes!!!! With the same weight and size you could EASILY bring WAY MORE power out of a turbine. But the hull, sprockets, tranny can't take the torque, rapid increase in power so the turbine is actually toned down. You can physically/visually warp the hull rear of an M1 if the engine is aloud to accelerate as fast as it actually can. It's governed.

What we need is the LV-100 or whatever the new turbine is called. SCREW DIESEL!