27 February 2021

25 February 2021

U.S. Medium And High Speed Rail Update


Outside the Northeast Corridor, intercity passenger rail service is limited to Amtrak, which provides infrequent (often once or twice a day) service at speeds averaging 40 miles per hour or less, at costs significantly greater than intercity bus service by far less heavily subsidized Greyhound with no meaningful advantage in speed relative to intercity bus service.

But significant progress in U.S. passenger rail service will arrive over the next six or seven years.

The only currently operating "high speed rail" routine in the U.S., such as it is, consists of a medium speed (66-82 mph) Northeast Corridor Acela route run by Amtrak that commenced service on December 11, 2000. It will be receiving new trains through 2022 which will increase its passenger capacity, make for more comfortable travel and slightly increase speed while leaving Acela ready to benefit from any infrastructure improvements that are made. The Northeast Corridor could have its infrastructure upgraded to double its speed but it would cost about $172 billion to upgrade the full 472 mile route that has not been approved at this time, although intermediate grade improvements in speed could be secured at an intermediate price.

There is a medium speed (79 mph) route in Florida from Miami to West Palm Beach that closed in March 2020 due to COVID and will reopen in late 2021. It will be extended to Boca Raton by mid-2022 and to Orlando by the end of 2022, with plans in place to further expand it from Orland to Tampa with no fixed timeline in place.

A high speed (200 mph) route from Las Vegas to Southern California starts construction in April with completion of a first phase planned for late 2024, and an extension bringing it closer to existing slow passenger rail lines into Los Angeles planned as a second phase.

A high speed (200 mph plus) route from Dallas to Houston starts construction in June with completion planned for 2027.

California and Nevada

A drawing of a Brightline West train on Interstate 15 between Las Vegas and Los Angeles. (Brightline West)

The red line low speed passenger rail lines currently exist; the blue line begins construction in April; the yellow line is in a design-concept phase only.

Construction on an $8 billion 170 mile bona fide high speed rail line from Las Vegas to Victorville on the outer fringe of the Los Angeles metro area, more or less along I-15 will probably begin in April of this year (a year behind a scheduled that was delayed due to COVID-19 related interruptions of a bond offering to pay for it). 

The company behind the plan, Brightline West, is also attempting to expand this first phase of the project to Rancho Cucamonga and Palmdale, California, where riders could then link to downtown Los Angeles via Metrolink. 

Realistically, a planned 2023 completion date for the portion of the route to Victorville will be pushed back to the end of 2024, but this is still less than four year away., will be the first truly high speed rail line in the United States. The new high speed trains will make the 170 mile trip in 85 minutes at an average speed of 200 miles per hour.

After missing its planned 2020 construction start date, the company behind the high-speed rail project between Las Vegas and Southern California is hopeful work could begin this year. Brightline West plans to begin construction on the approximately 170-mile rail line between Southern Nevada and Victorville, California, as early as the spring, according to a project status update filed Jan. 4 with the Nevada High-Speed Rail Authority. “The purpose of this letter is to provide a status update on the project, which is on target to commence construction in early Q2 2021,” Sarah Watterson, president of Brightline West, said in the letter. . . . 
Late last year, Brightline postponed a $2.4 billion bond sale that would have generated the financing for the initial portion of tracks and stations of the long-talked about $8 billion project. The company blamed the delay on market instability due to the ongoing COVID-19 pandemic. . .  . After Brightline canceled the bond sale, both California and Nevada repurposed the private activity bonds approved for the project — $200 million in Nevada and $600 million in California — to go toward affordable housing in each state. . . . stakeholders have expressed support for a new allocation of private activity bonds in 2021. . . . Terry Reynolds, director of the Nevada Department of Business and Industry, said there have been no discussions between the state and Brightline regarding the timing of reissuing private activity bonds. Mark DeSio, spokesman for California Treasurer Fiona Ma’s office, also said no talks have been had with Brightline this year regarding the potential reallocation of bonds. . . . “We would most likely be looking at a time frame around the third quarter of 2021,”[Reynolds] said.
Brightline spokesman Ben Porritt said the company continues to make progress on expanding its plans, looking to connect into Los Angeles County and is keeping officials in both states updated on developments. . . .

In addition to the planned Las Vegas to Victorville track, Brightline is also working on potential links to Rancho Cucamonga and Palmdale, California, where riders could then link to downtown Los Angeles via Metrolink.

From the Las Vegas Review-Journal (January 13, 2021). 


Image from here.

Sister company Brightline Florida has building a "medium speed" rail line, faster the Amtrak service in most of the U.S. and comparable to the service provided by Acela service in the Northeast Corridor, along the Atlantic coast of Florida starting at Miami to Orlando and then on from there to Tampa in a second phase. 

Service to three stations with a peak speed of 79 miles per hour on the first 72 mile portion of the route from Miami to West Palm Beach began in 2018 but was halted in March 2020 due to COVID. Service on this portion of the line is scheduled to resume in late 2021. As noted in a previous post at this blog:

An expansion to Orlando, a three hour, 240 mile trip from Miami with peak speeds of 125 miles per hour to the North of West Palm Beach, due to completed in 2022. This compares to highway travel times of 3 hours 30 minutes to 3 hours 45 minutes between the same destinations.

The anticipated Miami to West Palm Beach portion cost about $1.1 billion, and the West Palm Beach to Orlando route is anticipated to cost is $2.4 billion. 

Brightline Florida raised $950 million in a December 2020 tax exempt bond offering to financing continuing work on the West Palm Beach to Orlando leg of the project. The Boca Raton station is scheduled to open in mid-2022. the Orlando station is still on track to be completed in late 2022, less than two years from now.


Regulatory authorization is in place and $20 billion of construction by the Texas Central Railroad company  will begin by June of this year on a high speed rail line from Dallas to Houston that would make that trip in 90 minutes at speeds of more than 200 miles per hour. By I-45, the roughly 240 mile trip takes about three and a half hours. The sites of the Dallas, Brazos Valley and Houston stations and about 40% of the land for the track routes has been acquired. 

This Texas high speed rail project is scheduled to be finished in 2027.

Amtrak Service In The Northeast Corridor

About 38% of Amtrak service, as measured by passenger trips, are in the Northeast Corridor.

The Amtrak owned and operated Acela medium speed passenger rail line averages 82 miles per hour from D.C. to New York City, and 66 miles per hour from New York City to Boston (the full trip takes 6 hours and 40 minutes give or take about ten minutes). 

Acela service captures 75% of the air/train commuters between New York City and Washington D.C., and 54% of the combined air and train travel from Boston to New York City (but only 6% of all intercity trips in the region).

New train cars with more passenger capacity and the ability to handle upgraded rail lines and to travel slightly faster than existing train cars on 457 mile medium speed Acela line from D.C. to Boston will start to enter service this year and will fully replace the existing train cars by 2022. 

With $151 billion (in 2012 dollars, $172 billion adjusting for inflation but not for specific changes in the costs for this project) of infrastructure upgrades (at least some of which will very likely be funded in the Biden administration), the average speed could be more doubled, reducing the length of a trip from D.C. to Boston to about three hours. Intermediate expenditures could produce intermediate improvements and about $28 billion of infrastructure spending is needed in the Northeast Corridor simply to maintain the system at its current standards due to long deferred maintenance.

In the Northeast Corridor, Amtrak breaks even on operating costs due to passenger fares and high volumes of traffic (with considerable deferred maintenance and capital expenditure subsidies not considered, however).

Amtrak Service Outside The Northeast Corridor

Due to the realities set forth below, it would be better to eliminate passenger rails service entirely in most of the United States, where it persists only because of deep federal and state subsidies and mostly just takes a modest share of unsubsidized intercity private bus service that meets the same need more effectively. 

If Amtrak were to scrap this service in places that it is not competitive with the alternatives, and to use the resources saved to establish or improve high speed rail systems that are competitive economically because they offer an alternative that is better to consumers than the alternatives, the U.S. would be better off.

Image from here.


Amtrak owns two stretches of rail line outside the Northeast Corridor that could support medium speed (up to 110 mile per hour) service. These are the 104.2 miles of the Harrisburg Line (also known as the Keystone Corridor) between Philadelphia and Harrisburg, and a 95.6-mile segment called the Michigan line from Porter, Indiana, to Kalamazoo, Michigan. But Amtrak does not provide medium speed rail service on either of these routes. 

Outside its Acela route in the Northeast Corridor, Amtrak passenger train service is a little better than half the speed of travel by car on an interstate highway.

For example, if you want to go from Washington, DC, to Pittsburgh 250 miles away, you are looking at either a four-hour car trip or a seven-hour-and-43-minute Amtrak ride [less than 33 miles per hour]. What's more, there's only one train per day that makes the trip, departing DC a bit after four and arriving in Pittsburgh a bit before midnight. Of course, with the train so slow that there's no practical case for using it, there's little point in scheduling more trips. Megabus offers a slightly faster journey with two trips per day and charges $10 to $15, while Amtrak's fares start at $50.

Similarly, a trip from Denver to Glenwood Springs, Colorado, which is 157 miles and takes 2 hours and 33 minutes via I-70 by car (averaging 61 miles per hour), takes 5 hours and 41 minute via Amtrak (averaging 28 miles per hour), with only one trip available per day leaving at 8:05 a.m.

Average Amtrak service speeds outside the Northeast Corridor are comparable to intercity bus service (which are slowed by many stops en route) and are equally likely to be faster than slower.


In order to provide this inferior service, in addition to fares that average 35.6 cents per mile (including the Northeast Corridor) it receives combined federal, state and local subsidies of about 26.4 cents per mile for the system as a whole (including the Northeast Corridor which breaks even on operating costs although not in total costs) for a total cost of 62 cents per passenger mile. In all, Amtrak receives about $1.5 billion per year from the federal government and about $0.2 billion per year from state and local government. Amtrak's long haul routes are especially unprofitable.

Amtrak requires significant operating subsidies outside the Northeast Corridor. In a sample of 18 trips considered in one study:

For the remaining eighteen trips the average government (state and federal) subsidies to Amtrak range from $21.93/passenger to $289.56/passenger. By comparison, for the twenty trips analyzed the total indirect capital subsidies (Highway Trust Fund outlays) provided to support surface transportation range from $0.09/passenger to $0.74/passenger.

On selected long routes with low ridership (which are maintained, in part, for political purposes so that it can tout to Congress that it serves 46 U.S. states), the cost of a commercial airline ticket between the same destinations in many cases, with a flight time that is 10% of the Amtrak travel time. 

By comparison, air travel has a combined cost of about 15 cents per passenger mile (including about 1.25 cents per passenger mile of government subsidy), the combined cost of travel by car is about 24 cents per passenger mile (including an about 0.8 cent per passenger mile of government subsidy), and intracity public transit has a combined cost of about $1.21 per passenger mile made up of about 29 cents of passenger fares and 92 cents of government subsidies per passenger mile.

More background is available in a January 5, 2021 Congressional Research Service report which among other things recounts the fact that 2020, due to COVID, was a horrible year for Amtrak. 

Some of the unprofitability of passenger rail in the U.S. is a product of its low population density. Rail has high fixed costs that are paid for by high volumes of passengers in areas with high population density, but are much harder to justify on low traffic routes. As one critic in a carefully fact based critique observes, passenger rail service in other countries is also most profitable in areas with high population density:

Consider Japan. Three private companies operate trains on the main island, Honshu, and make money. But all three companies that operate on the other islands lose money and are regularly subsidized. . . . France has one high-speed train that makes money—between Paris and Lyon—and the rest lose money. Spain’s and Germany’s high-speed rail have done nothing to reduce car rides, but, instead, have cut into the market share of buses.

Market Share

Unless the comfortable and scenic trip across the country is the destination, this doesn't make any sense. This is why in 2019, Americans traveled an average of 15,000 miles by automobile, 2,100 miles by plane, 1,100 miles by bus, 130 miles by walking and bicycle, 100 miles by intracity rail, and about 20 miles per person by intercity Amtrak rail service. 

Outside the Northeast Corridor line service, as measured by passenger trips, about 18% is on short-haul corridors in California, about 5% is in New York State between Niagara Falls and New York City via Albany and Buffalo, and about 5% is on routes from New York City to Harrisburg, predominantly through Pennsylvania. This leaves about 34% of Amtrak trips outside of the Northeast Corridor and conventional routes in New York, Pennsylvania and California.

Environmental Impact

Amtrak is more energy efficient, consuming half as much energy per passenger mile as travel by personal passenger car, is 35% more energy efficient than traveling by bus, and is  40% more energy efficient than traveling by plane. But, these benefits are largely confined to its Northeast Corridor service. A study comparing Amtrak service to intercity bus service found that:

Excluding the Northeast Corridor, where Amtrak operates electric locomotives, the average impact of scheduled intercity motorcoach service on air quality is lower than the impact of Amtrak service. Average per-passenger emissions of particulate matter and nitrogen oxides are approximately 80% lower for motorcoach trips than for Amtrak trips, and average emissions of volatile organic hydrocarbons are approximately 90% lower.

Passenger Safety

Amtrak has about the same number of deaths per passenger mile as commercial bus service, which is much less safe than traveling by air (by at least a factor of thirty), but about 15 times safer than traveling in one's own personal car.  

24 February 2021

Split Tickets Rare In 2020

The total number of split districts in 2020 was 16 (3.7% of Congressional Districts).

Nine districts elected a Republican representative, yet voted for Joe Biden (many in California, but also Texas, Florida, Nebraska, Pennsylvania and New York).

Seven districts elected a Democratic representative while voting for Donald Trump (all in the Northeast or Midwest). 

This is the lowest level of district-splitting, both in percentage and absolute terms, since 1920, a full century earlier. That year, 11 out of 344 districts produced a split result (3.2% of Congressional Districts). 

In 2016 and 2012, 35 and 26 districts (respectively) split their tickets. 


Some of this is due to cleaner ideological sorting between candidates based upon party ID now that "realignment" has run its course. All liberal candidates are Democrats, all conservative candidates are Republicans. The last of the conservative Democratic candidates and moderate Republican candidates are disappearing. 

Gerrymandering can't explain much of the shift from 2012 to 2020 since all of the districts were drawn based upon the 2010 census.

Looking at the few districts that still did split, the Presidential vote tends to be a better reflection of local political leanings, with split tickets tending to reflect particular members of Congress who are more conservative Democrats, or more moderate Republicans, as the case may be, relative to the national Presidential candidate of the same party.

Also, partisan identities are hardening and the ranks of moderates are growing smaller. 

22 February 2021

U.S. Military Adopting Active Defenses For Armored Vehicles

The U.S. military is planning to add active defenses that attempt to shoot down incoming missiles and shells with computer targeted and fired bullets into its armored vehicles. Apparently, the technology, now proven by the Israeli military and trial by U.S. defense contractors, has finally reached a point at which it is "ready for prime time." The system also includes a "soft kill" system (e.g. jamming or confusing guidance systems in guided munitions). Some of the technology is illustrated in a Lockheed set of infographics focusing on the "soft kill" aspect and noting that: "In a series of live-fire tests conducted by the U.S. Army, MAPS-enabled systems defeated 15 out of 15 anti-tank guided missiles by jamming their signals, causing them to fly off-target." It still isn't clear, however, just how effective these systems are in realistic conditions, or what their limitations are. 

The Army will soon start testing a Lockheed Martin anti-missile defense system designed to work with the service's M1 tanks and Bradley and Stryker armored vehicles.

Under a three-year agreement announced Tuesday, Lockheed will provide its Modular Active Protection System, or MAPS, base kit, which includes a framework of vehicle sensors and countermeasures designed to detect, track and destroy rocket-propelled grenades and anti-tank guided missiles, according to a company news release. . . .

Lockheed began working with the Army to develop its MAPS technology in 2014.

"Since then, the MAPS base kit has proven itself in multiple live-fire demonstrations," said David Rohall, program manager for Advanced Ground Vehicle Systems at Lockheed Martin. "We're ready to support integration and testing on a variety of Army combat vehicles, the final step before the Army makes a formal decision on fielding this capability."

The service has been searching for an active protection system for more than 10 years. It selected the Quick Kill APS, made by Raytheon Co., to equip its manned ground vehicles under the Future Combat Systems program. The effort died, however, when then-Defense Secretary Robert Gates canceled FCS in 2009 -- the same year the Israel Defense Forces fielded the first Trophy APS systems.

The Army launched an accelerated effort in early 2017 to equip its M1 tanks, Bradley fighting vehicles and Strykers with commercially available active protection devices such as the Trophy system. The Army agreed to equip four brigade combat teams' worth of M1 tanks with the Trophy system and has tested the Israeli APS system, known as Iron Fist, to protect the Bradley.

Equipping the lightly armored Stryker with APS has proven more challenging, Army officials told Congress in March. The APS systems the Army tested could defeat an incoming missile, but it was difficult to prevent the secondary effects of the destroyed enemy rocket from penetrating the vehicle. . . .

The contract also covers developing the base kit for vehicle protection capabilities beyond active protection, such as underbelly blast protection, according to the release.

According to another source

The Army is exploring a plethora of anti-missile defenses for its armored vehicles. Many Abrams tanks already have the Rafael Trophy, a battle-tested Israeli countermeasure which physically shoots down incoming anti-tank rockets and missiles. The Army has also been working to integrate another off-the-shelf Israeli active protection system, Elbit’s Iron Fist, onto the M2 Bradley, albeit with mixed success and delays. Bradley’s a smaller vehicle than Abrams with less room and electrical power to add radar-controlled interceptors. And the service is trying out two slimmed-down systems, one by Rafael and one by Germany’s Rheinmetall, on the Stryker. As the lightest of the vehicles in question, it has proven the hardest to protect.

Iron Fist-Active Protection System Installed On A U.S. Army M2 Bradley Infantry Fighting Vehicle (Rada photo).

So the Army has plenty of irons in the fire – but that’s part of the problem. Each of these active protection systems takes a different approach to intercepting enemy anti-tank weapons. Each uses a different mix of radar and other sensors to detect the threat, different “hard-kill” interceptors and “soft-kill” jammers & decoys to defeat it, and different computer hardware and software to control it all. Each of them requires different training and tools to install, operate and maintain.

See also here

16 February 2021

U.S. Army Considers New Light Tank

A 2016 prototype model

U.S. Army modernization officials are looking for defense firms capable of producing lightweight tanks to arm infantry brigades with more firepower for the future battlefield. . . . 

"The MPF system provides early entry forces a mobile, protected, direct fire capability to apply immediate, lethal, long-range fires in the engagement of armored vehicles, hardened enemy fortifications, dismounted personnel and represents a long-term solution to the Infantry Brigade Combat Team (IBCT) capability," the document states.

The Army kicked off the MPF program in December 2018 by awarding contracts to General Dynamics Land Systems Inc. and BAE Systems Land & Armaments LP to produce early prototypes. The two companies will build 12 prototypes each for testing; the goal is to select a winner by fiscal 2022 and begin fielding the first of 504 of these lightweight tanks in fiscal 2025.

The MPF is planned as a tracked vehicle with a minimum crew consisting of a commander, gunner and driver, according to the document. It will be designed to protect the crew from small-arms fire, overhead artillery blasts, underbelly mine detonations and side improvised explosive device explosions, the document states. Army requirements call for the MPF to be armed with a 105mm, or possibly a 120mm, cannon to engage hardened targets at long range. . . .

Interested companies responding to the March 11 deadline must be able to provide evidence of their proven abilities to produce this tracked armored vehicle, the document states.

The MPF concept emerged several years ago when maneuver leaders started calling for a lightweight, armored platform armed with a large enough cannon to destroy enemy armor for light infantry forces. The idea was to field it to airborne units for forced-entry operations.

But the MPF will not be air-droppable. The current plan is to have Air Force C-17 Globemasters carry two MPFs each and deliver them after an airfield has been secured.

Airborne and other light infantry units can be used to seize airfields as an entry point for heavier follow-on forces, but they lack the staying power of Stryker and mechanized infantry.

The 82nd Airborne Division was equipped with the [17 ton] M551 Sheridan Armored Reconnaissance Airborne Assault Vehicle until the mid-1990s [wikipedia image below]. Developed during the Vietnam War, the Sheridan resembled a light tank and featured a 152mm main gun capable of firing standard ammunition or the MGM-51 Shillelagh anti-tank missile.


From Military.com

The MGM-51 Shillelagh missile has a 2 km range, but didn't fit a great need in the Vietnam War where the Sheridan tank was used most heavily, since the opposing forces largely lacked tanks or armored vehicles, and after Vietnam, an upgraded version of the missile with longer range that addressed flaws in the earlier system was only used six times in combat, all during the 1991 Gulf War to destroy bunkers.

It appears is that the intent of Army officials is to have a light tank that is more heavily armored than a Stryker armored personnel carrier, which is armored against heavy machine gun fire and some shrapnel, and more along the lines of a mine resistant ambush protected (MRAP) vehicle, but is not capable is sustaining a hit from a tank or artillery shell or a missile, or even the lighter end of anti-tank weapons.

While well intentioned and appropriately recognizing a need for an armored vehicle that is lighter than an M1 Abrams main battle tank (the latest version is 74 tons), with offensive capacities greater than small arms fire in hot battle zones for troops that are first to the fight,  this is the wrong solution. (See also previous analysis at this blog here).

The M1 Abrams main 120mm direct fire canon has an effective range of 3.5 km. The original 105mm direct fire canon of that tank (replaced in early trials) had an effective range of 2 km. While these are longer ranges than those at which small arms are accurate, a 105mm or 120mm direct fire canon is likely to have a range only marginally greater at best. 

This means that this light tank would be highly vulnerable to anti-tank missiles which are common in sub-"near peer" military forces, even infantry carried anti-tank missiles. Modern anti-tank missiles typically have ranges of 3.75km to 10 km, and can also be used against essentially any target that a tank round could be used against. A light tank would not survive being hit by a modern anti-tank missile.

As this article explains:

As the threat of advanced anti-tank guided missiles and other infantry anti-tank weapons continues to grow, numerous countries, including the United States, are adding active protection systems to their armored vehicles. While being able to defend against some kinds of incoming rounds is very important, it's even more important to kill the threat before it ever has a chance to fire in the first place[.]

This article also notes the limited effectiveness of even advanced countermeasures against advanced anti-tank weapons which are technologically viable. A discussion of the emerging countermeasures that are available and their limitations can also be found here.

One such active defense system (designed to work with armor since even a successful countermeasure would produce shrapnel) is the Israeli Trophy system which uses radar, automated targeting and firing faster than a human being could react, to shoot down high explosive anti-tank missiles, anti-tank rockets, rocket propelled grenades, tank shells and artillery shells with bullets of its own before they hit your armored vehicle. 


Germany has adopted the soft-kill MUSS system for the Puma, which uses a jammer and multi-spectral countermeasures to prevent air-launched and ground-launched guided weapons hitting the vehicle[.]
The same article notes that active protection systems also reduce the value of traditional direct fire tank guns against opponents with advanced military systems:
[I]f active protection systems can stop armour piercing fin stabilised ammunition. . . . the large cannons that characterise contemporary tanks will run the risk of becoming redundant. . . .
Ultimately, the question is what is the best way of destroying an armoured vehicle? If it is via specialised missiles and ATGMs, tanks in the future will move away from large cannons and the industry will have to react to that, which it already has to some extent with active protection systems.

The Marine Corps Approach Compared

The Marines have recognized the new technological reality and have eliminated tanks from their force, in favor of an intent to purchase joint tactical vehicles with mounted or towed missile launchers (with versions for anti-ship as well as anti-tank missiles).

In the past, part of the Marine tank mission profile was to take out other enemy tanks in pitched armor vs. armor battles. Now however, Marines will be able to take out enemy armor from much father distances than a tank is capable of, and without a heavy 74-ton armored platform.

Marine Lieutenant General Eric M. Smith explained this idea further during the International Armoured Vehicles Conference, held online this year due to the ongoing pandemic. USNI News quoted him, stating “the experimentation that we’ve done now to date successfully using lightweight mounted fires – think the back of a Joint Light Tactical Vehicle – is killing armor at ranges, rough calculation, about 15, 20 times the range that a main battle tank can kill another main battle tank.”


A Joint Light Tactical Vehicle at Marine Corps Base Camp Pendleton, California, on Oct. 24, 2019. US Marine Photo.

An example of a similar system to the one contemplated by the Marines with a Spike LR II anti-tank missile system, with a 5.5 km range, is shown below:

But, the Army is stuck in the mode of doing the same thing over and over again, even after the hopeful development of briefly having its outdated Sheridan tanks outfitted with anti-tank missiles (a capability used only rarely in Vietnam and in the Gulf War).

An Alternative: A Light Wheeled Missile Tank

A better solution would be wheeled armored vehicle designed for an optional crew of two, with no capacity to carry infantry soldiers, that mounts, instead of a 105mm or 120mm tank shell direct fire cannon, anti-tank and/or surface to air missiles, a remotely operated 25mm-40mm cannon (and possibly also a remotely operated machine gun).

Defensively, it would have an active protection like the Israeli Trophy system, and a guided missile jamming system like the German MUSS system (which weighs just 65-160 kg). The passive armor would be as heavy as possible consistent with C-130 transportability limitations on weight and dimensions, and would be at least up to MRAP standards. 

It should be limited to 36,000 pounds (18 short tons) to make it C-130 transportable, and to allow four of them to be delivered per trip of a C-17. This is a challenging, but not insurmountable standard, which had been met by other light tanks and armored vehicles with missiles in the past. If MRAP standards of armor protection could not be met with that weight limitation, the weight could be increased to up to 23 short tons, which would at least allow three of them, rather than two, to be delivered in a single C-17 trip.

Ideally, it would also have a small, limited range, dedicated rotary wing UAV to provide it with an "eye in the sky" to assist in identifying potential ambushes and targeting its missiles and active defense systems, as well as a remotely controlled cannon with firepower comparable to a semi-automatic carbine for engaging opponents in its main weapon system's blind spots and snipers that it identifies. The UAV could also provide an intermediate link for communications system when terrain or buildings are blocking communications signals.

Ideally, it would be 6x6 rather than 4x4 to limit its vulnerability if a single wheel is disabled. 

Ideally, it would be narrow enough to navigate narrow urban roads and bridges in places that do not have the same city planning tradition as the United States. 

Ideally, it would have some capacity to ford rivers, canals, ponds, wetlands, or short distances oversea from a landing craft to shore.

Why Wheels and Missiles?

A wheeled vehicle is faster, require less of a supply line of diesel fuel because wheeled vehicles are so much more fuel efficient, and would easier to repair in the field than a tracked vehicle. And, the off road capabilities and survivability of wheels v. tracked vehicles has largely equalized in recent decades. 

Missiles have a longer range, greater accuracy and pack an equal or more powerful punch. Also relevant is that a heavy M1 Abrams tank carries 40 tank shells and a light tank would probably carry somewhat fewer shells, so the reduced number of available rounds with a missile tank would be fairly modest relative to one with a large caliber cannon, particularly after considering that missiles are more accurate at long ranges.

Replacing tracks and a main direct fire cannon with missiles also both significantly reduce the vehicle's weight. So does eliminating the requirement to provide armored protection for a detachment of carried infantry found in otherwise comparable armored vehicles. 

This should make either the 18 short ton goal, and the 23 ton fallback goal attainable.

Weight Considerations For Light Tanks

Brenchmarks From Previous Military Vehicles

The M1 Abrams main battle tank's original version weighted about 69 tons but the latest version has grown to 74 tons. This one of the heaviest heavy tanks that has ever been mass produced. The heaviest tank that was ever mass produced beyond a few prototypes was Nazi Germany's 79 short ton Jagdtiger.

China's Type 99 main battle tank weighs 56-61 short tons.

South Korea's KNMBT main battle tank weighs 55 short tons.

Variants of the Russian T-90 tank weigh 51-53 short tons.

The German Puma IFV ranges from 35 to 47.5 short tons depending upon its level of armor protection.

The German Boxer wheeled armored fighting vehicle variants range from 26.4 to 42.4 short tons.

The World War II M4 Sherman tank had models that ranged from 33.4 to 42 short tons.

China's Type 15 light tank weighs 36 to 40 short tons.

The Russian VPK-7829 Bumerang Infantry Fighting Vehicle is about 38 short tons.

The Italian Centauro II wheeled tank is 33 short tons.

The BAE-Land RG 41 wheeled AFV/ACV is 29 to 33 short tons.

The U.S. M109A6 Paladin self-propelled howitzer weighs 31 short tons.

The base model of the M2 Bradley Infantry Fighting Vehicle is 30.4 short tons, and with additional elements it can be heavier.

The proposed Army light tank would be a weight at which only two could be carried per C-17 run, which suggests a weight of about 30-35 tons, similar to an M2 Bradley IFV, that is tracked, moderately heavily armored, has TOW missiles, has a 25mm cannon, and also carries six infantry soldiers.

Japan's Type 16 maneuver combat vehicle wheeled light tank weighs 28.6 short tons.

The Force Protection Buffalo MRV mine clearing Class III MRAP vehicle weighs 28 short tons.

An M270 MLRS (derived from the M2 Bradley chassis) is 27.5 short tons.

The wheeled Chinese NORINCO ZBL-08 (Type 8) Infantry Fighting Vehicle weighs 16.5 to 27.5 short tons.

The wheeled Turkish FNSS PARS anti-tank vehicle (which comes in 4x4, 6x6 and 8x8 variants) weighs from 17 to 27 short tons.

The French AMX-10 RC 6x6 wheeled tank weighs 17.4 to 24 short tons.

The Chinese tracked vehicle-mounted version of the HJ-10 anti-tank missile system weighs 22 short tons.

The Stryker M1128 Mobile Gun System weighs 20.7 short tons (about 2.5 tons more than a Stryker without it, which provides a useful benchmark to the weight added to a military vehicle by a main cannon system).

The M142 HIMARS weighs 17.9 short tons.

The M9 Armored Combat Earthmover weighs 17.75 short tons.

The Turkish ACV-15 Infantry Fighting Vehicle is 14-17 short tons.

The Vietnam era M551 Sheridan light tank weighed 17 short tons.

The World War II era M3 Stuart light tank weighed 16.75 short tons.

The heaviest of the U.S. Marine Corp LAV vehicles (for Light Armored Vehicle), the LAV-105, weighed 15.25 short tons.

The Chinese WZ550 tank destroyer weighs 15.1 short tons.

The now mostly retired M113 Armored Personnel Carrier had versions that weighed up to about 14 short tons and had a chassis that could support up to 15.5 tons.

The World War II era M2 light tank weighed 13 short tons.The MRAP program had many vehicles in three classes that made them quite heavy, more than 50% more than their base weight in many cases, when operating:

MRAPs come in three classes, from a variety of approved manufacturers — over 60 variations have been built. 
A Category I MRAP carries up to six passengers and weighs seven tons. 
Category II vehicles carry 10 passengers and weigh 19 tons. 
Category III is reserved for mine-clearing variants that carry up to 12 passengers; they can weigh as much as 22.5 tons. 
These categories can be misleading though, because personnel capacity varies by the equipment load-out of the passengers, and weight doesn’t account for all the various add-ons: weapon systems, radios, electronic counter-measures, fire suppression systems and, for additional protection from mines, extra armor. Operating weight can be over 30 tons.

The MRAP program has many Class II vehicles that weigh in at 15-18 tons with awkward dimensions that reach 30-40 tons when fully loaded and armored. 

The Soviet Era BRDM-2 9P133 Tank Destroyer weighed 8 short tons.

The experimental Ripsaw M5 robotic combat vehicle (RCV) weighs 7.2 short tons.

The EE-3 Jararaca weighs 6.4 short tons.

Joint Light Tactical Vehicle weighs 5.133 short tons gross weight, without a cargo payload and crew, and without armor add ons. The heaviest version, fully loaded, was limited by Army design specifications to 7.3 short tons.

The U.S. Avenger Air Defense System, designated AN/TWQ-1, which mounts anti-aircraft missiles on a Humvee, weighs 4.3 short tons (the anti-air missile system itself adds 0.5 short tons or less to the weight of the vehicle).

Helicopter Transportability Is Probably Unrealistic

Realistically, a heavy lift helicopter transport would be very challenging. 

A CH-53K King Stallion has a maximum capacity of 18 short tons. A CH-47 Chinook helicopter has a cargo capacity of 12 short tons. The maximum capacity of a CH-54 Tarhe sky crane helicopter is 10 short tons. The VTOL MV-22B Osprey tilt rotor Marine transport plane has a 10 short ton capacity and significant dimensional limitations on cargo as well. An ordinary CH-53 Sea Stallion helicopter has a maximum capacity of 4 short tons. 

Realistically, however, the practical weight limits in combat applications for these military helicopters are about two-thirds of their quoted absolute maximum weight. For example, the Army when bidding the JLTV set a maximum weight of 15,639 pounds (about 7.3 short tons) to meet its requirement that it be transportable by C-47F and CH-53K helicopters, which was less than their absolute maximum payload, to recognize that they can't be operating in battle conditions at maximum loads with no margins of error. This requirement ruled out some of the heavier JLTV proposals.

The King Stallion might be able to carry a 12 ton light tank, but it would realistically have to be a little under 8 tons to be CH-47 transportable, to get to a vehicle that is consistently transportable by helicopter in deployments into potentially hostile areas.

A 8 ton limit, or even a 12 ton limit, would be very light for even a light armored tank, so a goal of a helicopter transportable light tank is probably unrealistic.

C-130 Weight Limitations

These changes could probably make it possible to design an acceptably capable and armored light missile tank down to be C-130 transportable (17-18.25 tons depending upon the model)

A single basic model Stryker, a Marine LAV, or an M113 can be carried in a C-130, although heavier Stryker models, such as its mobile gun system variant and models with slat armor, cannot be without being partially disassembled and broken into two loads. 

Two of the base model of Joint Light Tactical Vehicle can be carried by a C-130. 

The C-130 has a fully loaded range of 2,080 miles at a cruising speed of 336 miles per hour. It has a takeoff distance of 3,586 feet fully loaded and 1,400 feet empty.

C-17 Weight Limitations

Short of either of those possibilities, reducing the wheeled missile tank's weight can increase the number of them that can be transported via a C-17 long range military transport plane.

A C-17 long range military transport plane can carry one M-1 Abrams tank, one Patriot missile launcher system (with some disassembly and reassembly required), two M2 Bradley fighting vehicles, two multiple rocket launcher systems, two UH-60 Blackhawk helicopters, three AH-64 Apache attack helicopters, four combat-ready Stryker armored personnel carriers, or  ten Humvees with TOW rocket launcher systems. A Congressional Research Service report diagram, below, illustrates its capacity (and the capacity of the larger C-5 military transport aircraft which has about twice the cargo capacity but requires higher quality airstrips than the austere airstrips that a C-17 can manage). 

Limiting a proposed new light tank to 18 tons, about the same as a basic Stryker armored personnel carrier, would allow four of them to be carried on a C-17, doubling the number that could be transported per C-17 flight from the current proposal, in addition to making it C-130 transportable.

Limiting a proposed new light tank about 24 tons would allow the delivery of  three of them per C-17 sortie instead of two, increasing air deployment rates by 50%, over the current proposal.

The C-17 has a fully loaded range of 2,780 miles at a cruising speed of 520 miles per hour. It has a takeoff distance of 8200 feet fully loaded and 3000 feet empty.

Allied Transport Aircraft

Joint operations are the norm in modern military engagements so consideration of the cargo capacity of allied military transport aircraft is also appropriate.

Many European military forces use the Airbus A400M Atlas, that entered service in 2013, which has a 40.8 short ton capacity. It has a fully loaded range of 2,100 miles at a cruising speed of 485 miles per hour. It has a takeoff distance of 3,215 feet fully loaded and 2,530 feet empty. This is enough to carry on M2 Bradley Infantry Fighting Vehicle or two Stryker armored personnel carriers, but not enough to carry an M1 Abrams main battle tank.

The Japanese military uses the Kawasaki C-2 military transport plane that entered service in 2016, which has a capacity of 41.4 short tons (similar to the A400M) and a fully loaded range of 2,800 miles at a cruising speed of 550 miles per hour. It has a takeoff distance of 7,546 feet half loaded and 1,640 feet empty.

Other Weight Considerations

Excessive size has other disadvantages too:

The [typical fully loaded Class II MRAP] vehicle's weight and size severely limits its mobility off main roads, in urban areas, and over bridges, as 72 percent of the world's bridges cannot hold the MRAP. Its heft restricts transport by C-130 cargo aircraft or amphibious ships. Three MRAP vehicles (or five Oshkosh M-ATVs) fit in a C-17 aircraft, and airlifting is expensive, at $150,000 per vehicle, according to estimates by the U.S. Transportation Command.
When the MRAP was introduced around 2007 during the Iraq War:
The US Air Force contracted several Ukrainian Antonov An-124 heavy-cargo aircraft, which became a familiar sight above cities such as Charleston, South Carolina, where some MRAPs are produced. For comparison, sealifting costs around $13,000 per vehicle, but takes 3–4 weeks for the vehicle to arrive in theater.

Real World Examples Of Similar Vehicles

Consider the following realized versions of similar concepts.

Similar Vehicles With Main Tank Guns

Traditional Tracked Light Tanks

The Chinese Type 15 light tank entered service in 2017.

The United Defense M8 Advanced Gun System was proposed as a replacement for the Sheridan tank in 1995 and prototypes were built, but it never entered mass production. It would have weighed 19.25 to 24.75 tons depending upon armor strength, had the program not been cancelled in 1997.

Wheeled Tanks and APCs With A Main Cannon

The 30 ton Italian Centauro II wheeled tank was designed in 2016 (also discussed here).

The Japanese Type 16 maneuver combat vehicle wheeled light tank with a 105mm main gun weighs 28.6 short tons.

The French AMX-10 RC 6x6 wheeled tank (formally designated as a reconnaissance vehicle) designed in 1970 has a 105mm main gain and weighs 17.4 short tons in its base variant and 24 short tons in its heaviest IED resistant variant.

The 20.7 short ton Stryker M1128 Mobile Gun System is a wheeled armored personnel carrier with a 105mm tank cannon. Its light armor for a tank and limitations on transporting it with a C-130 military transport aircraft have been criticized: "
the mass of the [vehicle] exceeds the carrying capacity of the C-130 aircraft, so you have to remove equipment, a set of screens, and sometimes even a cannon from the car. The armor can be pierced by Soviet made RPG-7 projectiles." Also, the "large weapon station and relatively smaller hatch can make emergency exits difficult. Because the main cannon is separated from the crew compartment a gun stoppage during combat can only be cleared by disembarking from the vehicle."

Tracked Armored Personnel Carriers Without Missiles

The tracked Swedish Combat Vehicle 90 weighs 25 to 39 short tons, is optimized for subarctic weather, and is distinguished by its very low profile. It carries 8 infantry soldiers and mounts a 40mm auto cannon as its main weapon. Prototype version of the CV 9040 equipped with the Bofors RB56 anti-tank missile called the Stridsfordon 9040/56 were developed, but issues with the sight alignment were unsolved and no units ordered.

Similar Vehicles With Missiles Instead of Main Tank Guns

Wheeled and Tracked Missile Tanks

A new tank destroyer concept, built for the Polish Army, armed with up to 24 Brimstone anti-tank missiles (which have a 40km+ range) that can unleash a salvo of tank-hunting missiles, knocking out enemy tank units it can’t actually see (via Popular Mechanics, September 5, 2019). See also here

concept vehicle based upon the German Boxer armored personnel carrier, but armed with Brimstone anti-tank guided missiles and Common Anti-Air Modular Missiles has been proposed, and fits the idea of a wheeled missile tank well, although this would be a fairly heavy design.

A new Chinese vehicle-mounted version of the HJ-10 anti-tank missile system (from an August 2020 report, see also here and here) in its tracked configuration that carries four missiles is shown above. 
The HJ-10 anti-tank missile is touted as a Chinese equivalent to the US Hellfire system, which has been bought by the Indian Air Force for its Apache attack helicopters. The HJ-10 comes in both fibre optic-guided, laser and radar-guided versions and is available in both air- and ground-launched versions. It can be used against tanks, surface targets and even helicopters and is estimated to have a range of around 10km. 

The Chinese WZ550 tank destroyer (a wheeled 4x4 version of the ZSL92 mounting a traversable weapon station firing 4 HJ-9 anti-tank missiles with a 5.5 km range) that has a crew of three and does not carry infantry soldiers. It weighs about 15.1 short tons. This is a 4x4 version of the 6x6 version used in the Chinese Yi Tian anti-aircraft vehicle  below. This combination debuted in 1999 and the underlying APC entered service in 1986. More background is available here.

The Chinese Yitian Wheeled Self-Propelled Short Range Air Defence System (SHORAD) comprises of 2 quad launchers equipped with TY-90 (Tian Yan ) surface-to-air missile with range of 6 km (according to a 2012 report). The gun is a 12.7mm heavy machine gun and it also has smoke grenade launchers. It is amphibious and more heavily armored than its predecessor.

Tracked Armored Personnel Carriers With Missiles

The M2 Bradley Infantry Fighting Vehicle has a 25mm cannon, a 7.62mm mounted machine gun, and TOW missiles, and carried six infantry soldiers in a 30 ton moderately armored tracked vehicle. A modernized missile tank version could reduce weight by dispensing with the infantry carrying capacity and would have a design more sensitive to IED threats. During the Persian Gulf War, M2 Bradleys destroyed more Iraqi armored vehicles than the M1 Abrams. Twenty Bradleys were lost—three by enemy fire and 17 due to friendly fire incidents; another 12 were damaged. The gunner of one Bradley was killed when his vehicle was hit by Iraqi fire, possibly from an Iraqi BMP-1, during the Battle of 73 Easting. To remedy some problems that were identified as contributing factors in the friendly fire incidents, infrared identification panels and other marking/identification measures were added to the Bradleys. In the Iraq War, the Bradley proved somewhat vulnerable to improvised explosive device (IED) and rocket-propelled grenade (RPG) attacks, but casualties were light—the doctrine being to allow the crew to escape at the expense of the vehicle. As of early 2006, total combat losses included between 55 and 150 Bradleys. By 2007, the Army had stopped using the M2 Bradley in combat, instead favoring more survivable MRAPs. By the end of the war, about 150 Bradleys had been destroyed. From 2005-2007, a small number of Bradleys were converted to M6 Linebacker units that had four anti-aircraft Stinger missiles instead of TOW missiles.

The German Puma IFV (image from here) which is also tracked, has similar armaments (including a 30mm cannon, MUSS active defense system, and Spike LR anti-tank guided missile with a 5.5 km range), a six soldier passenger capacity, and somewhat better armor protection. It entered service in 2012, has been considered by the U.S. Army to replace the M2 Bradley.

An M-113 armored personnel carrier, modified to launch Hellfire missiles, is shown above (from here). The M901 ITV used TOW missiles on an M-113.

An Anti-Aircraft Missile Variant of the 13-15 ton Turkish ACV-15 Infantry Fighting Vehicle.

A modern tracked British light missile tank also intended to carry some infantry soldier passengers is shown above.

Wheeled Armored Personnel Carriers With Missiles

BAE-Land RG 41 wheeled AFV/ACV, equipped with missile firing unit.

M1134 Anti-Tank Guided Missile Vehicle is a U.S. armored fighting vehicle based on the Stryker vehicle with TOW missiles (which have a range of 3.75km) similar to the system that I would propose, but the Stryker lighter armor and more infantry capacity than my proposal.

A Stryker version with Hellfire missiles (which have a range of 8km).

The image above from a February 2019 trade show is a Chinese a wheeled VN-1 (a.k.a. ZBL-09 Snow Leopard) armored personnel carrier mounted with a large battery HJ-10 (a.k.a. Red Arrow 10) anti-tank missiles (which are comparable to U.S. Hellfire missiles and can also be used against helicopters). The standard version of this APC has two HJ-73 anti-tank missiles with a 3 km range (a Soviet designed counterpart to the U.S. TOW missile), a 30mm cannon, carries 7-10 infantry soldiers, and weighs 16.5 to 22 short tons. 

The 34 ton VPK-7829 Bumerang is a modular amphibious wheeled infantry fighting vehicle and armored personnel carrier scheduled to enter service in the Russian Army in 2021 whose remote weapon station turret with 30 mm automatic cannon 2A42, 9M133 Kornet-EM anti-tank missiles (with an 8 km range) and PKT 7.62 mm coaxial machine gun or AU-220M Baikal remote weapon station with 57 mm BM-57 autocannon and 7.62mm PKMT machine gun (a missile tank version would omit the infantry soldier passenger capacity).

Germany also has a similar system called the Boxer armored fighting vehicle, which is wheeled. In a Lithuanian version it has machine guns, a 30mm cannon and Spike anti-tank guided missiles, in addition to carrying eight infantry soldiers. It is almost 43 short tons in weight, in part, because it needs to have the capacity to carry personnel, rather than merely being a tank.

China's NORINCO ZBL-08 (Type 8) armored fighting vehicle, currently in active service in the People's Liberation Army there, also has similar capabilities and a similar design.

Lightly Armored Wheeled Vehicles With Missiles

A U.S. Army AN/TWQ-1 Avenger Air Defense System. The combined Humvee base and missile system weigh only about 900 pounds more than the lightest Humvee model and only about 100 pounds more than the heaviest Humvee model. The missiles are Stinger missiles that are 5 feet long, weigh 33.5 pounds each, have a 6.6 pound warhead and cost $38,000 each. It has a range of 3.8km to 4.8 km depending on the altitude of the target (the longer range is for higher altitude targets) and travels at a peak speed of Mach 2.54.

A new light four by four wheeled vehicle mounted with two HJ-10 anti-tank missiles (which can also be used against helicopters and is comparable to the U.S. Hellfire missile) is displayed in the August 2020 photos above from the mountainous plateau region of China (probably Tibet or near the border with India). An August 2020 report discusses it:
Global Times notes "Another newly revealed weapon is the vehicle-mounted version of the HJ-10 anti-tank missile system. Compared with the original version that uses tracks and is loaded with four missiles, this new version uses four wheels and is loaded with two missiles." 

This configuration reduces weight, allowing ease of transportation. . . . The use of wheeled carriers for both the howitzer and anti-tank weapons is significant as wheeled platforms are considered more suitable for high-altitude regions than tracked vehicles (common in battle tanks) as the latter are significantly more heavier.

A Soviet Era BRDM-2 9P133 Tank Destroyer (whose anti-tank missiles had a 3km range).

EE-3 "Jararaca" light and lightly armored wheeled armored reconnaissance vehicle was developed by Brazilian company "Engesa" at the end of 1970s. Vehicle is intended for reconnaissance and patrolling, and is fitted with anti-tank or anti-aircraft guided missile complexes. It is used with Brazilian armored forces and is exported to Greece, Cyprus, and a number of African and Latin-American countries. The tank destroyer configuration with anti-tank missiles is primarily used in Cyprus.

A Turkish FNSS PARS anti-tank vehicle (4x4 version) (see also here). It is fitted with an unmanned turret carrying four OMTAS missiles and a 7.62x51 mm machine gun. The locally-developed Roketsan OMTAS medium range anti-tank missile is infrared guided, has a range of 4 km and has lock on before launch, lock on after launch, fire and forget, and man in the loop firing modes. A similar system, called ASELSAN is described here.

Historically, the BAE Ferret Mark 5 Scout Car with Swingfire missiles, introduced in 1968, shown below, was similar.

Small Anti-Tank Ground Drones

The experimental Ripsaw M5 robotic combat vehicle (RCV), an unmanned light tank with a Common Remote Weapon Station-Javelin (CROWS-J) turret mounted with a Javelin anti-tank guided missile with a 2.5 km to 4.75 km range and a cost of about $190,000 each, and either an M2 .50 machine gun, M240 7.62mm machine gun, or an MK-19 40mm automatic grenade launcher (AGL), weighs 7.2 short tons.

The Islamic Republic of Iran Army Ground Forces' Heidar-1 project, a group of small, "network-connected anti-infantry and armor smart UGVs" (unmanned ground vehicles) prototypes were on display at an Army weapons expo in Tehran in October of 2019. The six-wheeled UGVs come in six versions—including two that carry assault rifles mounted to their tops and one that is essentially a mobile anti-tank mine. 

Mobile, Ground Based Long Range Missile Systems

The Army and Marines are both considering ground based anti-ship and long range cruise missile systems, so that they can have an anti-ship capability that they now lack, particularly in the Western Pacific theater. 

Danish mobile missile battery (shown above) with four anti-surface combatant Harpoon missilesidentical to those used on U.S. Navy ships as anti-ship missiles, would be one way to achieve this capacity with existing technologies and systems. A Harpoon missile weighs 1,523 pounds, is 15 feet long, delivers a 488 pound warhead, has a 170 mile range which it traverses at 537 miles per hour skimming over the sea. Each missile costs $1.41 million. While this is expensive, the target naval ship sunk with one would typically cost hundreds of millions or billions of dollars to purchase.

A very similar system, but using Tomahawk land attack missiles (normally used for naval ship to shore missile strikes) would also be a very straightforward option for ground forces seeking to supplement air strikes. Each Tomahawk missile weighs 2,900-3,500 pounds (depending upon whether or not it has a booster), it 8 feet and 9 inches long, delivers a 1,000 pound warhead (or a nuclear warhead), and has an 810 mile range which it traverses at 550 miles per hour traveling 98-164 feet above the ground. Each missile costs $1.54 million. This is close to the 1,000 mile range artillery system that the Army has been seeking to procure.

A variant of the Harpoon missile designed for land attack strikes called a SLAM missile could also be used as a long range artillery missile, but would be about twice as expensive per missile ($3.03 million) as the Tomahawk missile, despite a somewhat smaller warhead (800 pounds) and much shorter range (170 miles at 531 miles per hour). It is about half the weight of a Tomahawk missile (1,598 pounds), and but is much longer (14.3 feet).

All of these missiles, however, would still easily fit on a short semi-trailer.

Currently, the U.S. military has two kinds of multiple rocket launcher systems launching the same collection of medium range surface to surface missiles, the M270, which is armored and can launch twelve missiles in two six missile pods, and HIMARS which is unarmored and can launch six missiles in one pod.

The M270 Multiple Launch Rocket System is a tracked vehicle designed to launch non-line of sight missiles, which is based upon a stretched M2 Bradley Infantry Fighting Vehicle chassis. It carries twelve missiles of one or two of about a dozen different types with ranges from 20 to 103 miles. It must be accompanied by an M269 Launcher loader module. The missiles are 12.93 feet long and weigh 560-675 pounds, with warheads up to about 200 pounds, some of which have submunitions (although the longest range ones, the MGM-140 Army Tactical Missile System (ATacMS) have a larger diameter and weigh up to 3,890 pounds and have one rather than six missiles per pod).

The M270 is too heavy to transport by helicopter or C-130 but a C-17 can transport two of them per trip.

The M142 HIMARS is the unarmored cousin of the M270 MLRS that has half the capacity, but launches the same varieties of missiles. It weighs 17.9 short tons and can be transported with a C-130 military transport plane.