WATCH

This is the last tank airborne units jumped into combat

[brid video="114003" player="7965" title="Military Insider M551 Sheridan"]Airborne forces face a problem whenever they have to jump behind enemy lines — whether it's to seize an enemy airfield or to take and hold territory.


The paratroopers can't bring their own armor support, because America doesn't currently have an airborne-certified tank or large armored vehicle. (The Stryker and the Light Armored Vehicle have undergone successful airdrop tests, but neither has been certified).

But it wasn't always this way. During the Cold War, Airborne forces relied on the M551 Sheridan, an Airborne-capable light tank first fielded in 1969.

The M551 Sheridan tank was a 16-ton tank made primarily of aluminum and employed by airborne forces. (Photo: U.S. Army)

The Sheridan was a replacement for the World War II-era Mk. VII Tetrarch tank and the M22 Locust Airborne tank. The Tetrarch was a British glider-capable light tank and the M22 was an American tank custom-built for glider insertion.

The M551, unlike its predecessors, was airdrop-capable, meaning it could be inserted using parachutes instead of gliders. The tank was also used with the Low-Altitude Parachute Extraction System, an airdrop system that allowed the U.S. to drop the tanks from a few feet to a few dozen feet off the ground.

An M551 Sheridan is pulled from the back of a C-130 by the Low-Altitude Parachute Extraction System. (Photo: U.S. Air Force)

The Sheridan was crewed by four people and weighed 16 tons, light enough that it could actually swim through the water. It was powered by a 300-hp diesel engine and could hit approximately 45 mph. It could travel 373 miles between fill-ups.

The tank used an experimental 152mm gun that could fire missiles or tank rounds. Even its tank rounds were experimental, though — they used a combustible casing instead of the standard brass casings.

The M551 Sheridan tank firing a Shillelagh missile. (Photo: U.S. Army)

The Sheridan served well in Vietnam and Panama. During Operation Just Cause, it was even airdropped into combat, allowing paratroopers to bring their own fire support to the battlefield.

The tank's main gun could inflict serious damage at distances of up to 2,000 feet, allowing it to punch out enemy bunkers from outside the range of many enemy guns.

Unfortunately, the light armor of the Sheridan posed serious issues. Some Sheridans were pierced by enemy infantry's heavy machine guns, meaning crews had to be careful even when there was no enemy armor or anti-armor on the field. Worse, the main gun started to develop a reputation as being unreliable.

Firing the main gun knocked out the electronics for the longer-range missile, meaning that a tank firing on bunkers or enemy armor at close range would usually lose their ability to punch targets at long range. And there was no way to avoid this issue as the Shillelagh missile couldn't hit targets at less than 2,400 feet.

The only way for an M551 to punch at close range was to give up its capability at long ranges.

By 1980, most cavalry units were moving to the M60 Patton Main Battle Tank, which was actually introduced before the Sheridan. The Patton featured heavier armor, more power, and a more reliable gun. It had also just been upgraded with new "Reliability Improved Selected Equipment," or "RISE."

According to an Army history pamphlet, one cavalryman told the Stars and Stripes, "We can get the job done with the Sheridan, but most cavalrymen would rather have the tank."

The airborne forces would keep the Sheridan through 1996, partially because they had no other options. A number of potential replacements were canceled and modern airborne forces just make do without true armored support.

The Army is, once again, looking at new light tanks or heavy-armored vehicles to support paratroopers. The new solution could be another custom-built tank, like the Sheridan. But as of summer 2016, its specifications were up in the air. It just has to be capable of an airdrop, and it has to get the job done.

GEAR & TECH

6 of the most notable pre-M16 military guns

Throughout history, the U.S. Military has used a wide variety of guns to win its battles. Prior to the M16, there were several weapons used across the service throughout some of the most devastating wars the world has ever seen.

Here are some of those weapons:

Keep reading... Show less
Articles

How R. Lee Ermey's Hollywood break is an inspiration to us all

While there have been many outstanding actors and celebrities who have raised their right hand, there has never been a veteran who could finger point his way to the top of Hollywood stardom quite like the late great Gunnery Sergeant R. Lee Ermey.

Keep reading... Show less
International

China and the US could end up in a war – here's what would happen

It's unlikely that the U.S.-China trade dispute is going to escalate to a full-scale war any time soon — but it's not impossible. Neither side is inclined to go to war with the other, but a war of that scale is what both plan to fight. All it would take is one bungled crisis, one itchy trigger finger, one malfunctioning automated defense system and the entire region could become a war zone.

Keep reading... Show less
Lists

Here are the best military photos for the week of April 20th

The military is always evolving and new things happen every day. With each changes comes a new set of challenges and new opportunities to succeed. Thankfully, there are many talented photographers in the community that capture these struggles and triumphs.

Keep reading... Show less
History

5 ways troops accidentally 'blue falcon' the rest of the platoon

Every now and then, the pricks known as 'Blue Falcons' come and ruin things for everyone else. They break the rules and make everyone else suffer. They rat out their brothers- and sisters-in-arms. They even damage the reputation of others to make themselves look better.

Keep reading... Show less
Articles

Why I'm thrilled Brie Larson will play Captain Marvel

Look, the Marvel Cinematic Universe is really lighting my fires when it comes to their female superheroes.

When Marvel Studios announced they would be bringing Captain Marvel to the big screen, I was thrilled. I was also immediately invested and my expectations shot through the roof.

Keep reading... Show less
History

This is how American pilots used drop tanks as bombs during WWII

If you pay attention, you might sometimes see long, cigar-shaped pods firmly attached to the undersides of classic fighter and attack aircraft, sometimes with unit markings on them.

Known as "drop tanks," these simple devices extend the range of the aircraft they're hooked up to by carrying extra usable fuel. Back during World War II, however, attack pilots found a secondary use for drop tanks as improvised bombs, used to bombard enemy ground positions.

Keep reading... Show less

The hilarious ways Chinese police are combating jaywalkers

China is so desperate to stop jaywalkers it has turned to spraying them with water.

In Daye, in the central Hubei province, one pedestrian crossing has had a number of bright yellow bollards installed that spray wayward pedestrians' feet with water mist.

Keep reading... Show less