1944 the dimmapur to kohima to Ifal road northeast India 130 mi of winding hill track and the only supply route for over 150,000 British and Indian troops of the fourth corps Japanese forces from the 31st division have cut it felled trees captured lorries overturned across bends anti-tank guns cighted for pointblank fire down the road infantry dug into both flanks unarmored convoys trying to push through are being destroyed This is one of the most effective Japanese tactics in Burma and it is bleeding the 14th army dry.

The solution according to every senior commander in the theater is tracked vehicles, tanks, M3 lees and M4 Shermans.

In the jungle and hills of early Burma, where roads of few and monsoon mud swallows trucks whole, wheeled armored cars are considered not suited to the theater.

Multiple reconnaissance units have already abandoned their armored cars, replacing them with jeeps and universal carriers.

The 45th reconnaissance regiment has been converted wholesale into Chindit longrange penetration infantry.

The seventh cavalry regiment has traded in its armored cars for Steuart light tanks.

This story is about a vehicle everyone wrote off and why Burma’s roads made that a mistake.

The Humber armored car was never supposed to exist.

In 1938, Guy Motors of Wolverampton designed a welded armored car body when the War Office insisted that welded armor construction could not be done.

Guys engineers did it anyway at their own expense, pioneering a technique that eliminated the deadly problem of rivet spalling, where rivets inside the crew compartment turn into projectiles when armor is struck.

Guy built 101 armored cars before the war’s demand exceeded their small facto’s capacity.

After Dunkirk, production had to scale.

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Guy transferred their jigs and welding designs to the Roots Group.

Roots took Guy’s armored body and married it to the Carrier KT4 artillery tractor chassis, a four-wheel drive vehicle with its engine relocated to the rear.

The result was an ungainainely hybrid.

Despite known faults carried over from the Guy design, the War Office ordered immediate production.

The vehicle was branded Humber to avoid confusion with the tracked universal carrier.

And in 1945, that ungainainely hybrid would be out in front of Shermans, leading the most dramatic armored advance of the Burma campaign.

According to production records, Roots built approximately 5,400 Humber armored cars across four marks between 1941 and 1944 at the Luton Works of Comma Cars Limited and facilities in Coventry.

The early Marks, the Mark 1 and Mark 2, carried a 15 mm Bisa machine gun, a big awkward beast by armored car standards.

Over 6 ft long and weighing more than 125 lb, it was prone to stoppages, and its armor-piercing performance disappointed in trials.

Both Marks used a three-man crew.

The Mark III introduced a significantly larger turret with a dedicated wireless operator, bringing the crew to four.

This freed the commander from radio duties, but the 15 mm baser remained and its problems remained with it.

The MarkV fixed the gun problem.

Roots replaced the 15 mm Bisa with the American 37 mm M6 gun, the same weapon fitted to the M3 Stewart light tank and the M8 Greyhound armored car.

The larger gun ate the wireless operator’s space, forcing a return to a three-man crew, a driver, a gunner, and a commander.

But the firepower increased more than compensated.

The 37 mm could fire armor-piercing rounds, high explosive rounds for fortified positions, and canister rounds for massed infantry.

Each canister shell contained 122 precision machine steel pellets that formed a shotgun-like cone lethal to exposed troops at ranges up to 250 yd.

The MarkV weighed 7.1 toners.

Depending on source and mark variant, top speed is often given as 45 to 50 mph and range is 200 to 250 mi.

Armor thickness reached 14 to 15 mm at the front and 10 mm on the sides.

Enough to stop rifle and machine gun fire, not enough to stop a dedicated anti-tank round.

According to service reports, the vehicle was described as rugged, reliable, and operationally sound with the only reported defect being a short engine life.

Crews particularly liked it as a command vehicle because it offered more internal room than the alternative dameler armored car.

The problem this vehicle solved in Burma was about roads.

Burma’s motorable road network was extremely sparse.

Dense tropical jungle, mountain ranges reaching 8,000 to 10,000 ft along the Indian border, river valleys, and swampland dominated the landscape.

The few roads that existed were everything.

They were the only way to move guns, armor, vehicles, and supplies.

And the Japanese knew it.

Same pattern every time.

A bend, a block, a gun, and infantry on the flanks.

At Taian in March 1942, a single roadblock nearly destroyed the entire Burma army.

The headquarters, the 17th Indian Division, and the Seventh Armored Brigade were all trapped.

Multiple infantry assaults failed to clear it.

The garrison only escaped when the Japanese voluntarily withdrew.

During the Impal and Kohima battles of 1944, roadblocks severed the fourth core from supply and reinforcement for weeks.

Unarmored convoys on these roads were defenseless.

Something had to escort them.

Something fast enough to respond, armored enough to survive small arms fire, and armed enough to suppress ambush positions.

If you are enjoying the way strange engineering decisions end up deciding battles, subscribe because now we are going into the Humber’s best day in Burma.

The turning point came in late 1944.

After the 14th Army shattered the Japanese 15th Army at British and Indian forces crossed the Chinduin River and broke out onto the dry belt of central Burma, the Arawadi plane where the road network was better and the terrain was open.

For two years, armored car crews had precious little chance to operate in their dedicated role.

Now they could.

The 16th light cavalry was India’s oldest armored regiment formed in 1776.

It was also the first Indian armored regiment commanded by an Indian officer, Lieutenant Colonel Ganto Nath Chowuri, who would later become the fifth chief of army staff of the Indian Army.

Chowderi took command in September 1944 and was twice mentioned in dispatches for gallant and distinguished services in Burma.

His regiment was equipped with Humber Markvs and Dameler armored cars organized into armored car troops, jeep mounted motorized infantry, and self-propelled 3-in mortar sections.

In early 1945, the regiment received orders for Burma.

Within 3 weeks, the 16th light cavalry covered 3,500 m from Queta to the banks of the Irati River.

Only a wheeled unit could have moved that fast over that distance.

General Slim personally complimented them for the speed of deployment.

By February 15, 1945, they had rejoined the 255th Indian Tank Brigade.

The battle that proved the Humber’s worth was makea.

On February 21, the 17th Indian Division, the Black Cats, with the 255th Tank Brigade, broke out of the Irrawi bridge head at Nyangu and drove toward McTa, the critical Japanese supply hub in central Burma.

The reconnaissance spearhead was a composite group called Tom Force.

Armored cars from the 16th light cavalry and PAVVO cavalry led the way, screening the entire advance.

Tangar fell on February 24.

Thatton airfield was captured that same afternoon.

By February 28th, four columns launched simultaneous attacks on Mcila against approximately 4,000 Japanese defenders from the 168th Infantry Regiment.

After the town fell, the Japanese counterattacked with elements of three divisions.

General Cowan adopted an active defense, sending armored columns, including the 16th light cavalry Humbers, out of the town every day to strike the surrounding enemy.

Five columns sorted on March 5.

A second series began on March 9.

Japanese forces in Burma generally lacked effective anti-armour weapons, relying instead on infantry tactics that required soldiers to physically close with armored vehicles against daily armored sorties armed with 37 mm guns and canister rounds.

Those tactics produced devastating Japanese casualties.

At wetlet on March 8, 1945, a column built around the 9inth battalion border regiment.

Sherman tanks from the Royal Deck and Horse and reconnaissance from the 16th light cavalry advanced northwest from Mectila to strike a battalion of the Japanese 106th Infantry Regiment.

According to accounts compiled by Brian Perro in tank tracks to Rangon, the armored cars and carriers of the 16th light cavalry led the column into the engagement, covering tree lines with machine gun fire as infantry advanced into fortified village positions.

Japanese heavy machine guns and a concealed 37 mm anti-tank gun engaged the leading vehicles.

A Dameler armored car was hit and caught fire.

Sherman tanks and 25 pound artillery were called forward for direct support.

The action lasted approximately 4 hours.

After the Japanese began withdrawing from Make Tie on March 29, the fourth core advanced nearly 200 m south toward Rangon with the 16th light cavalry screening ahead.

Piab Tungu Pew and Pagu fell in a rapid succession.

At Pegu from April 27 to the 30th, the Japanese mounted fierce resistance using anti-tank mines improvised from aircraft bombs and suicide attacks with pole charges.

The monsoon broke on May 2.

Leading troops met the 26th division which had landed at Rangon by sea through operation Dracula at leu on May 6th, 1945.

The campaign was over.

The 16th light cavalry earned seven battle honors.

Mctila, capture of MTa, defense of Mtila, Rangun Road, Pegu 1945, Sitang 1945 and Burma 1942 to45.

Now consider the Humber against its Japanese equivalents.

The most common Japanese armored vehicle in Burma was the type 95 Hgo light tank weighing 7.4 to 8.1 tons with a 37 mm gun and armor of roughly 12 mm.

Its top speed reached 28 mph with a range of approximately 130 mi.

The Humber carried equivalent firepower while being significantly faster on roads and possessing substantially greater operational range.

Against Japanese Type 94 and Type 97 tankets, many armed only with 7.7 mm machine guns, the Humber was overwhelmingly dominant.

Its 37 mm could destroy them at combat range, while their machine guns could not penetrate even the Humber’s 10 mm side armor.

The American M8 Greyhound carried the same 37 mm gun with slightly better frontal armor at 19 mm, but American cavalry men in Europe criticized its off-road performance as marginal, particularly in mud.

I have found no solid evidence of M8 Greyhounds being used in the Burma campaign.

British and Indian units largely relied on their own armored cars for the theater, and the Humber’s advantages were specific to Burma’s demands.

Lower weight for crossing improvised wooden bridges that could not support heavy tracked vehicles.

Reduced noise signature compared to tracked platforms critical for reconnaissance.

Simpler maintenance in a theater where every spare part arrived by air from India.

The Humber outlived nearly every tank it served alongside.

After the war, over a dozen nations adopted it.

India and Pakistan used them into the 1960s.

In 1962, Indian Humbers were airlifted to Chuchel at altitudes above 14,000 ft during the Sino-Io Indian War.

Portuguese Humbers saw service in Africa.

And then on April 25, 1974, a 1942 vintage Humber armored car rolled through the streets of Lisbon during the Carnation Revolution, helping overthrow a 48-year dictatorship that gave the Humber a 32-year operational lifespan from manufacturer to its last documented combat use.

Lord Mountbatton once told the troops of the 14th Army that at home they were not forgotten.

They had not even heard of them.

The same could be said of the Humber, a vehicle the British establishment dismissed as not suited to Burma.

Built on an artillery tractor chassis from a company that no longer exists, crewed by Indian cavalrymen whose regimental history was split between three nations after partition, it was never glamorous.

It was fast, reliable, and armed with the right gun for the theater it fought