background image

file:///H|/Modellismo/AFV%20Interiors/[armor]%20-%20AFV%20Interiors/afvinteriors.hobbyvista.com/mkv/mkv1.html

British Mk.V* Tank 

 
 

Picture 1: 
The British 
Mk. V* tank 
was a 
continuation 
of British 
WWI tank 
development 
that had begun 
with the Mk.I 
design of 
1916. The Mk.
V* was a 
lengthened 
Mk.V, the 
only 
difference 
between the 
two being 

additional plates that were added to the Mk.V behind the gun sponsons to lengthen the hull for improved trench crossing and 
provide additional internal space for carrying troops or equipment. Except for the extra armor plates, the running gear and 
other automotive components were almost identical in the Mk.V and Mk.V* tanks. This is a photo from the 

Imperial War 

Museum

 library of a Mk.V*. Note the open door on the hull side, behind the gun sponson. This door was added along with 

the additional plates to make the lengthened chassis of the Mk.V*.  
 
There were a number of improvements in the Mk.V and Mk.V* over their predecessors (like the famous Mk.IV) which 
greatly changed the way the crew managed the tank. For instance, the Mk.V and Mk.V* tanks featured a new Wilson 
epicyclic gearbox and brake that replaced the earlier change-speed gearing. The new steering system required only one 
steering crewmember, rather than the two used previously, the new driver called the "operator". Another important change 
was that both the Mk.V and Mk.V* were powered by the purpose-built Ricardo tank engine which required less service and 
broke down less frequently than the previous engines. The Mk.V* went into production at Metropolitan Carriage and Wagon, 
Birmingham, in December of 1917.  
 
This is the first part of a two-part exploration of the interior of the Mk.V* WWI tank. This series is an improved and 
expanded version of a web page first published in AFV INTERIORS in 1997.  
 
 

file:///H|/Modellismo/AFV%20Interiors/[armor]%20-%20AFV%20Interiors/afvinteriors.hobbyvista.com/mkv/mkv1.html (1 di 7)25/05/2007 16.54.45

background image

file:///H|/Modellismo/AFV%20Interiors/[armor]%20-%20AFV%20Interiors/afvinteriors.hobbyvista.com/mkv/mkv1.html

 

Picture 2: 
As I mentioned, the Mk. V* was simply a Mk. V tank lengthened by six feet behind the side sponsons with the intention of 
improving its trench crossing ability as well as providing transport space for troops or supplies. Initially, Mk. V* tanks 
originated as Mk. Vs that were altered in workshops in France, lengthened by the addition of three 2ft wide plates. But later 
production tanks were special made in England to this new length. Overall, roughly 580 Mk. V* tanks were produced and had 
just come into service when the Armistice was signed to end WWI.  
 
The Mk. V* proved to be a robust design and it was a very handy vehicle with its increased payload area. Some were used, 
for instance, by the US 301st Tank Battalion which operated under British control at the end of the Great War. This diagram 
from the Imperial War Museum shows the basic layout of the Mk. V* with driver sitting up front (our right). He is now the 
sole controller of the tank, using a 4-speed gearshift lever and two steering levers to control the steering and brakes on the 
epicyclic gearbox. Next to the driver (on his left) is a front hull machine gunner, and behind the driver is the new Ricardo 
engine with exhaust pipes exiting the tank directly over the engine through a muffler system. Behind the engine is the 
expanded cargo area, and after that is the gearbox, epicyclic gears, and the radiator and fan. In the very rear of the vehicle, 
actually outside the rear plate, are the three gas tanks between the rear drive sprockets. There were gun sponsons located on 
each side of the tank, and if it were mounted with 6pdr guns the vehicle was termed a male and if machine guns were the sole 
armament the tank was called a female. Let's take a closer look now at this drawing and see what detail is hiding there for us 
to discover.  
 
 

Picture 3: 
This is a detail study of the front 
of the tank, mainly showing the 
operator's position. His seat is 
just about directly in front of the 
engine, and he is provided with 
an opening visor flap for 
forward viewing. There is also 
an over-head hatch for entrance 
and exit, should his way be 
blocked back through the 
vehicle on either side of the 
engine. The engine behind his 
seat is covered with a metal 
shroud to protect the crew from 
direct contact and a fan at the 
rear of the shroud forces air 
from around the engine through 
a ventilation grating on the roof. 
This helps to remove the heated 
air around the engine that may 

file:///H|/Modellismo/AFV%20Interiors/[armor]%20-%20AFV%20Interiors/afvinteriors.hobbyvista.com/mkv/mkv1.html (2 di 7)25/05/2007 16.54.45

background image

file:///H|/Modellismo/AFV%20Interiors/[armor]%20-%20AFV%20Interiors/afvinteriors.hobbyvista.com/mkv/mkv1.html

also contain fumes. As far as I 

can tell, this is the first time consideration of the crew from heat and fumes was shown by isolating the engine. There is a 
water tank and revolver case for the front crewmen located in the left side wall, under the track run, to the left of the machine 
gunner sitting to the left of the driver.  
 
Some of the driver's controls are drawn here and they include his forward-reverse lever that you see rising and angling 
slightly back, located on the right side of his seat. Three other levers rise on either side of his seat and here these levers are 
seen angling forward. Two of them are his control levers, one at each side of the seat, and they steer the tank via the 
epicyclics at the rear. The other control lever is also located to the right of his seat, but it is the "change gear" lever, the 
gearshift. You can also see the location of the foot pedals mounted down on the floor; there is a clutch pedal to the left and a 
brake to the right. These will be seen better in the next drawing. Notice that the engine is elevated on a shelf. Power is 
transferred from the engine to the driveshaft down near the floor via gears around the flywheel and at this end of the 
driveshaft.  
 
 

Picture 4: 
This is an overhead view of the driver's area of a Mk.V, more or less the same layout that existed in our Mk.V*. Now 
the relative locations of the driver's and gunner's seats are shown in relation to the engine and its protective shroud. 

Notice that the water tank and revolver case are in the sponson to the gunner's left, and the driver's seat is just about 
surrounded by control levers of one type or another. The steering levers are drawn very close to his seat, while the change 
speed and forward/reverse levers are a bit further away to his right. The brake and clutch pedals are also shown, as well as 
something called an officer's locker in the sponson to the driver's right.  
 
The inline design of the Ricardo engine is shown, with the carburetor on the left and the intakes curving around to the right. 
Notice that a water hose is shown leaving the top of the case and turning to the rear where it travels along the ceiling back to 
the radiator at the right-rear of the tank. We will see this hose later in a picture taken inside the vehicle.  
 
 

Picture 5: 
And this is an 
enlargement of 
the same sketch 
showing the rear 
half of the tank. 
The driveshaft 
arrives at the 
Wilson gearbox 
you see here from 
the engine at the 
front of the tank, 
and from the 
gearbox the drive 
is directed 
sideways to 
epicyclic gears 
mounted on both 
sides of the hull. 
These gears then 
provide power 
through chain 
drives to 

reduction gears that directly engage the drive sprockets, utilizing the same gear teeth that engage the track. The three armored 
fuel tanks are shown attached to the rear of the hull, while the single oil tank is drawn above them. Also on this rear armor 
wall is a ball mount for a machine gun, similar to the two others you see in the cupola, or turret, up on the roof. This cupola is 
just an iron box and does not rotate, but it does provide improved vision around the tank and a good place to mount machine 
guns fore and aft.  

file:///H|/Modellismo/AFV%20Interiors/[armor]%20-%20AFV%20Interiors/afvinteriors.hobbyvista.com/mkv/mkv1.html (3 di 7)25/05/2007 16.54.45

background image

file:///H|/Modellismo/AFV%20Interiors/[armor]%20-%20AFV%20Interiors/afvinteriors.hobbyvista.com/mkv/mkv1.html

 
The series of vertical parallel lines in front of the oil tank identifies the tall water radiator for cooling the engine. This was 
composed of a number of vertical pipes with spaces between for air to flow through. Hot water from the engine was pumped 
into the top of the radiator and then the radiator-cooled water was returned to the engine from the bottom. The water tank 
(header) is is shown located directly in front of the radiator. On both walls, located both in and outside the sponsons, are racks 
and storage tubes for many 6pdr. rounds (if the tank is a male), and the new side doors (in the lengthened section of tank) are 
also identified in this sketch under ball mounts for two more machine guns.  
 
 

Picture 6: 
The top view shows the location of the three fuel tanks at the 
rear of the tank, separated from the hull interior by a steel 
bulkhead. The location of the fan shroud on the left side of the 
hull and the tubular radiator on the right is also clear. The 
radiator is also shrouded so air drawn into the fan from the left 
is blown across the radiator and exhausted through the louvers 
on the right hull wall. Note that the water tank illustrated in the 
last picture is a vertical tubular type that is located in front of the 
radiator. The epicyclics are indicated by the metal covers that 
look like bulges on the interior hull walls. The chain drive is 
illustrated running from the epicyclic gears to smaller reduction 
gears, which then directly engage the drive sprockets at the stern 
sponsons.  

 
 

Picture 7: 
A view of a Mk. V* 
during construction in 
the Metropolitan factory 
shows a few more 
interior details. 
Metropolitan Carriage 
and Wagon, 
Birmingham, started life 
in 1845 as Joseph Wright 
& Sons, and in 1863 
became the Metropolitan 
Railway Carriage & 
Wagon Company, 
builders of mostly 
railway cars and 
equipment. By 1902 the 
company had become 
the Metropolitan 
Amalgamated Railway 
Carriage & Wagon 
Company, later 
shortened to 
Metropolitan Carriage 
and Wagon. It was a 
natural fit for new tank 
building and 

file:///H|/Modellismo/AFV%20Interiors/[armor]%20-%20AFV%20Interiors/afvinteriors.hobbyvista.com/mkv/mkv1.html (4 di 7)25/05/2007 16.54.45

background image

file:///H|/Modellismo/AFV%20Interiors/[armor]%20-%20AFV%20Interiors/afvinteriors.hobbyvista.com/mkv/mkv1.html

construction during the Great War, having built large iron and wood railroad cars for many years.  
 
Visible here, toward the rear, are many of the 380 stowage tubes for 6pdr shells. Also visible is the new open side door 
located in the additional side plates that are characteristic of the Mk.V*. Notice the stowage bins visible through the side 
sponson openings. The gun sponsons would hold 6pdr guns in the "male" version of the tank, or additional machine guns if 
the tank was constructed in the "female" form. There were roughly even numbers of both types produced by Metropolitan. 
The pipe protruding out the side of the hull is where the epicyclics will be located, and the opening on our side of the pipe will 
eventually be covered with louvers for air intakes/exhausts to cool the radiator/engine.  
 
The basic Mk.V* tank weighed around 33 tons, and some of that weight is due to the double wall construction for the track 
run that was typical of early British tanks of the time. Although the space was not wasted (ammo and other stowage was 
placed there) the additional weight of this steel decreased the potential overall performance of all the early tanks and, added to 
the additional length of the Mk. V*, decreased the maximum speed to only 4 mph. The maximum armor thickness was 12mm 
(roughly 1/2in) at this time, a small improvement over the Mk.IV.  
 
 

Picture 8: 
This is one of my photographs 
of one of the few surviving Mk. 
V* tanks, this one is located in 
the collection at the 

Patton 

Museum of Armor and Cavalry

 

at Ft. Knox, Kentucky. You are 
looking forward through the 
new right side door of the cargo 
area toward the left sponson 
(shadows off in the distance). 
The 6pdr. guns have been 
removed from the sponsons. 
Closer to the camera is the 
cargo area with the drive shaft 
running close to the floor from 
the engine at the front to the 
gearbox behind. Off to the right 
is the starter crank for the 
engine, which is mounted even 
further off to the right. It took 
four men to crank over the 

engine while the driver operated a hand-starting magneto switch.  
 
Directly across from us is the opposite door on the left hull side and above that is one of the round ports for a ball-mounted 
Hotchkiss machine gun (the ball mount missing). The innovative ball mount seen in British tanks from the late Mk.IV on 
greatly improved the firing arc possible with the machine guns (from 60degrees to 90 degrees) and provided added protection 
for the crew. This is because the ball mount allowed less bullet splash to enter into the interior; previously the crew fired their 
MG's through open ports. This ball MG mount was invented by Mr. Skeens and it became standard production for all AFVs 
by the end of the war. The ball mount design would have made Skeens a hero to the tank crews, if only they had known who 
he was at the time.  
 
 

Picture 9: 
This is a view of the same Patton Museum 
vehicle, but this time looking aft, showing 
the 6pdr. ammo storage along the wall in the 
rear (as we saw previously in the factory 
photograph). There is a similar ammo rack 
on the other side of the hull. Also visible 

file:///H|/Modellismo/AFV%20Interiors/[armor]%20-%20AFV%20Interiors/afvinteriors.hobbyvista.com/mkv/mkv1.html (5 di 7)25/05/2007 16.54.45

background image

file:///H|/Modellismo/AFV%20Interiors/[armor]%20-%20AFV%20Interiors/afvinteriors.hobbyvista.com/mkv/mkv1.html

here is the large round epicyclic gear 
housing (also known as planetary gears) 
mounted in the sidewall, and the large 
shroud around the fan is visible on this left 
side of the tank. There is a second epicyclic 
housing on this side of the hull, but instead 
of a fan, there is the radiator. The metal 
shroud curves down after the fan before 
curving up again around the radiator in order 
for there to be room above the shroud to 
mount a rear-facing MG ball mount on the 
rear armor wall. Once power was transferred 
from the gearbox to these two epicyclic 
gears, chain drives brought power to small 
reduction gears, which in turn then powered 
the two drive sprockets. All the epicyclic 
gears do is convert the high revolutions of 
the drive shafts coming from the gearbox 
into low revolutions and high torque to drive 

the sprockets, due to the size difference of the two meshed gears.  
 
To steer the tank left or right, the driver pulled back the corresponding control (steering) lever, which in turn released a pinion 
in the epicyclic gear allowing it to idle and the corresponding track to slow, and eventually, stop. As the track slowed, the tank 
would slowly turn in that direction. The driver could make a sharper turn in the same direction by adding some brake pedal 
pressure and stopping the track more quickly. Also down near the floor are some of the control rods attached to the driver's 
levers and foot pedals up front and stretching all the way back to the gearbox and steering linkages in the rear. Notice the 
elevated wooden platform used to stand on by the machine gunners while using their MGs in the weapons ports in the over-
head cupola. You can just imagine the noise and smell inside one of these beasts in action when the machine guns were 
rattling, the engine roaring, and an occasional 6pdr firing, all within the echoing confines of this hot, dark, gyrating metal box. 
What a nightmare it must have been to work inside one of these tanks.  
 
 

Picture 10: 
A drawing of the left side 
drive train from the gearbox 
at the lower right to the drive 
sprockets at the far left 
shows the layout of the 
epicyclic gears, the chain 
drive, the reduction gear, and 
the sprockets. Most of this 
was protected inside the 
sponson.  

 
 

Picture 11: 
This photo shows the same general 
location in the tank again. This time we 
have moved up to the right-hand 6pdr 
sponson, and we are looking through the 
front of the sponson back toward the rear 
of the interior. Above can be seen the 
gunner's top cupola mentioned earlier 
and one of the ports for a rear facing 
MG, and to the right is another port for 
the left side MG located over the cargo 

file:///H|/Modellismo/AFV%20Interiors/[armor]%20-%20AFV%20Interiors/afvinteriors.hobbyvista.com/mkv/mkv1.html (6 di 7)25/05/2007 16.54.45

background image

file:///H|/Modellismo/AFV%20Interiors/[armor]%20-%20AFV%20Interiors/afvinteriors.hobbyvista.com/mkv/mkv1.html

door. Four additional machine guns were 
added to the Mk.V series from the 
previous Mk.IV, the two in this over-
head cupola "turret" and one in each of 
the side sponsons. Again, off in the 
distance, you can see storage racks for 
ammo, and nearer to us is the engine 
starting crank.  
 
To the far left of the photo is the latch 
for the door in the sponson we are 
looking through; there was a door 
located in the rear section of both side 

sponsons. The entire 6pdr mount has been removed from this sponson and its absence allows our view. The interiors of these 
early vehicles were generally painted white to improve visibility, but they probably did not stay that way for long with hard 
use. This particular photograph shows the interior of the Patton vehicle to be yellow, but the color is due to the film 
processing and incandescent lighting, not the actual color (white) the museum has painted the interior.  
 
This consludes Part 1. Part 2 will continue or examination of the interior of the Mk.V*.  
 
 

TO MK.V* PART 2

 

BACK TO AFV INTERIORS HOME PAGE

 

(c) 2002, 2003 AFV INTERIORS Web Magazine 

file:///H|/Modellismo/AFV%20Interiors/[armor]%20-%20AFV%20Interiors/afvinteriors.hobbyvista.com/mkv/mkv1.html (7 di 7)25/05/2007 16.54.45

background image

file:///H|/Modellismo/AFV%20Interiors/[armor]%20-%20AFV%20Interiors/afvinteriors.hobbyvista.com/mkv/mkv2.html

British Mk.V* Tank, Part 2 

 
 

Picture 1: 
This is Part 2 of 
a two-part series 
exploring the 
interior of the 
British WWI 
tank Mk.V*. 
This 

Tank 

Museum

 photo 

was taken inside 
their preserved 
Mk.V tank in 
the early 1960's. 
The photo 
shows the view 
looking toward 
the front of the 
AFV along the 
right side of the 
hull. You can 
see the intact 
Ricardo engine 
off to our left; 
the protective 
metal shroud 

has a flat hinged cover on this side that has been completely removed to reveal the engine inside. Up forward on the 
right are shelves for ammunition and other stores, but the partitions have been lost that would separate the bins for 
each MG ammo box.  
 
Up at the very front of the AFV is the elevated crossbeam platform for the driver and front hull machine gunner. We 
can see the driver's change speed lever (gearshift) close to his seatback and the forward-reverse lever further to the 
right. The driver's right steering lever is mostly hidden by the seatback, except for the very end of the handle. The 
driver's seat was just slightly to the right of being directly in front of the engine, while the front gunner's seat to his left 
was almost touching the left sponson wall. The driver's seatback was actually touching the front shroud of the engine 
and very close to the front armor of the tank. There was not much room for his seat in these tight quarters.  
 
Personal accounts indicate that starting the engine in cold weather required priming of each engine cylinder through 
its priming cock, having first warmed the spark plugs (two each cylinder) on a pile of burning cotton waste. When the 
engine was really cold, crews are said to have warmed the priming petrol outside the tank by lighting it in a tin. Once 
the fuel had warmed, a tight fitting lid was placed over the tin to extinguish the flames and the fuel then used to prime 
the engine. Off to the right is a very dark 6pdr and mount that unfortunately does not show up very well in this light.  
 
 

Picture 2: 
This photo 
was taken 
inside the 
same Mk.V 

 16.54.56

file:///H|/Modellismo/AFV%20Interiors/[armor]%20-%20AFV%20Interiors/afvinteriors.hobbyvista.com/mkv/mkv2.html (1 di 7)25/05/2007

background image

file:///H|/Modellismo/AFV%20Interiors/[armor]%20-%20AFV%20Interiors/afvinteriors.hobbyvista.com/mkv/mkv2.html

vehicle at 
Bovington 
and shows 
the 
components 
looking 
toward the 
right side of 
the hull from 
the left gun 
sponson. 
Again, the 
characteristic 
6pdr. ammo 
rack is on 
the wall near 
the rear of 
the 
compartment, 

and the epicyclic gear housing is seen below. We can look across to the right sponson and see the rear door that is 
painted a darker shade of paint, and also the ball mounting for the MG.  
 
To our left is the rear of the engine shroud and engine, visible only because this is a short Mk.V, not a Mk.V*. The 
ducting on this end of the shroud is the fan exhaust that pulls air surrounding the engine out through louvers in the 
ceiling. If this was an extended Mk.V*, we would not see the engine and shroud here, but instead see the additional 
hull wall plates directly across from us; the engine would be further off to the left. Up on the ceiling is the radiator 
hose leading back toward the radiator, which is out of our view to the right. The roof cupola is just about directly 
above us, and the machine gunner's raised wooden platform is at the bottom of the picture.  
 
 

Picture 3: 
This is a well-known photo from the 
Imperial War Museum (as many of 
these photos are) of tank gunners and 
instructors examining the 23cal 6pdr 
Hotchkiss naval gun and mount 
typically found in male Mk.IV and Mk.
V/Mk.V* tanks. Earlier marks had used 
the original longer barreled version of 
the naval 6pdr, but its length had 
caused problems so this shorter version 
was developed especially for these 
tanks. Half of the Mk. V* tanks built 
were female types, armed only with six 
Hotchkiss machine guns, while the 
other half were males, armed with two 
of these 6pdr naval guns (one in each 
side sponson) and four Hotchkiss MGs 
in ball mounts. The short 23cal 6pdr 
was used in both Mk.IV and Mk.V 
tanks, so these photos are applicable to 
both marks. There was normally an 

eight-man crew in these Mk.V* tanks: commander, driver, two machine gunners, and two 6pdr gunners (male tanks) 

 16.54.56

file:///H|/Modellismo/AFV%20Interiors/[armor]%20-%20AFV%20Interiors/afvinteriors.hobbyvista.com/mkv/mkv2.html (2 di 7)25/05/2007

background image

file:///H|/Modellismo/AFV%20Interiors/[armor]%20-%20AFV%20Interiors/afvinteriors.hobbyvista.com/mkv/mkv2.html

or 4 total machine gunners (female tanks), and two loaders. There were basic telescopic sights for the main guns and 
loopholes and peep slots for the machine guns. Unfortunately, due to the distance the machine gunners stood from 
their sights, the field of view outside was extremely limited.  
 
 

Picture 4: 
This is a view of a preserved 6pdr 
gun preserved at The Tank 
Museum in Bovington, England. 
The main recuperator is the 
cylinder you see on top, two 
recoil springs are mounted 
underneath, and the copper 
colored breech is mostly lost in 
the shadows to the right. 
Typically, the gun cradle was 
mounted on its pintle on top of an 
armored box, which also 
contained storage holes for 20 or 
so 6pdr. rounds. Approximately 
380 of these rounds were carried 
inside the Mk.V* and over 7,000 
machine gun rounds were also 
available, stored in wooden 
boxes.  

 
On this left side of the gun mount you can see the elevation and traverse locks and two brackets to hold the telescopic 
sight. The bracket at the rear is a cylinder shape and the one at the front, bolted to the mount at its pivot, looks like a 
Y. Field of view for these short 6pdr guns was only 20 degrees through the telescope. Range was estimated by eye and 
a drum was then adjusted on the side of the mount, which depressed the line of sight in relation to the gun axis. This 
gave the necessary additional elevation to compensate for gravity effects on the shot when the telescopic sight was 
laid on the target. It was a fairly simple system, but effective enough for these early tanks. The gun had a manual hand 
crank for traverse and was elevated by shoulder pad control. We have not been able to find much about the telescopes 
used with these 6pdrs. in tanks. If you can shed some light on this subject, we would be eternally grateful....  
 
 

Picture 5: 
This is the right side and breech of 
the naval 6pdr. The breech block is 
of the vertical falling type and is 
worked by the hand crank on the 
side of the breech ring. Visible here 
is the left recoil shield and aiming 
handle (minus its padded grip), and 
the cylindrical rear mount for the 
telescopic sight is also visible. 
There were three types of ammo 
that could be carried-- AP, HE and 
case shot (called "K-shot") for anti-
personnel work. This was made of a 
sheet metal case containing steel 
balls and a small bursting charge 
inside set to detonate on contact. 

 16.54.56

file:///H|/Modellismo/AFV%20Interiors/[armor]%20-%20AFV%20Interiors/afvinteriors.hobbyvista.com/mkv/mkv2.html (3 di 7)25/05/2007

background image

file:///H|/Modellismo/AFV%20Interiors/[armor]%20-%20AFV%20Interiors/afvinteriors.hobbyvista.com/mkv/mkv2.html

The AP ammo wasn't developed 
until 1918 and was then provided 

for the Mk.IVs and Vs that were still in service. It has been written that the sighting telescope had only a slight 
magnification, perhaps 2x.  
 
 

Picture 6: 
This photo shows the Ricardo engine designed for 
the new tanks, in this case being pulled out of the 
vehicle for maintenance. For its time, the Ricardo 
was a light-weight and powerful engine, producing 
a minimum of 150bhp at 1200 rpm. It was a 
straight 6-cylinder type with removable panels on 
the crankcase allowing most maintenance to be 
performed without having to lift the engine like 
this. Twin oil scavenge pumps, crosshead design, 
and pressure lubrication helped cut down on oil 
smoke in the exhaust which was so prominent with 
the Daimler 105hp sleeve-valve gasoline engines 
used in earlier Mks. Two carburetors and magnetos 
helped to reduce engine faults and the pistons were 
lubricated by oil splash. Unfortunately for the 

crew, cooling air for the large tube water radiator at 
the rear of the vehicle was drawn from outside the tank, rather than being supplied from the interior and then being 
blown out which could have cooled the interior air considerably. This made the interior of the Mk.V and V* tanks 
hotter and more unbearable than they had to be. And yet, on the whole, the Mk.V was still fairly popular with crews, 
primarily due to the improved driving ease of the beast and the fact that the engine was relatively trouble free 
compared to earlier designs.  
 
 

Picture 7: 
The Ricardo engine used 
in the Mk.V and Mk.V* 
was designed by the 
gifted engineer Harry 
Ricardo, the engine 
having to meet difficult 
requirements established 
by Albert Stern (then 
Commissioner for 
Mechanical Warfare) for 
tank use. The new 
engine was required to 
develop at least 150hp 
and operate at great 
angles without burning 
oil. Neither aluminum 
nor high tensile steel 
could be used, due to 
their need in other 
armaments.  
 
So like the Daimler 

 16.54.56

file:///H|/Modellismo/AFV%20Interiors/[armor]%20-%20AFV%20Interiors/afvinteriors.hobbyvista.com/mkv/mkv2.html (4 di 7)25/05/2007

background image

file:///H|/Modellismo/AFV%20Interiors/[armor]%20-%20AFV%20Interiors/afvinteriors.hobbyvista.com/mkv/mkv2.html

engine it replaced, Harry Ricardo designed his powerplant as an in-line 6-cylinder type, but he increased the cylinder 
capacity by building the engine taller with longer cylinders and subsequent longer throws and displacement. You can 
see how the engine is fairly simple in design with its tall exposed cylinders bolted vertically above the long crankcase. 
The exhaust valves are all exposed on this right side; the exhaust is routed away via two exhaust pipes, which turned 
up and exited through the roof of the Mk.V*. Also clearly visible in this photo are three of the access plates along the 
engine case that simplified repair and eliminated the need to remove the engine for minor maintenance problems. The 
large geared flywheel is to the left (rear of the engine) and you can see the dual magnetos at the right.  
 
 

Picture 8: 
This photo shows 225 B.
H.P. Ricardo tank 
engines under 
construction at Messrs. 
Gardner's Works, in 
Manchester, during 
World War I. Sir Harry 
Ricardo was born in 
London in 1885 and was 
educated at Rugby and 
Cambridge where he 
studied at Trinity 
College. Harry Ricardo 
certainly knew engines, 
and the one he designed 
to be used in the Mk.V* 
employed four 
horizontal valves 
operated by push rods 
and bell cranks, 
something no one else 

had ever tried. They also introduced a new design known as a crosshead piston, and the results were so successful that 
Ricardo Consulting Engineers produced around 8000 of these engines for tanks, with many more powering generators 
in workshops, hospitals, and military camps. Some were even used in railway shunting locomotives and in marine 
propulsion. The success of the engine venture led to Harry Ricardo buying the land and setting up a laboratory on its 
present company site in 1919. Many other successes were credited to Ricardo over the years, including the Octane 
Rating Scale. Harry Ricardo invented a unique variable compression ratio engine dedicated to fuels research, and that 
is what led him to devise the fuel rating index known today as the Octane Rating.  
 
 

Picture 9: 
So what is a crosshead piston design anyway? In short, 
crosshead-type pistons can use the lower side of the piston 
crown as a supercharger, and the crown of the piston is 
therefore isolated from the crankcase chamber and very 
effective oil control can be maintained with little visible 
exhaust smoke. The word "crosshead" comes from earlier steam 
engine designs were a crosshead connected a steam engine's 
piston to the rotating wheel, allowing movement from the up 
and down moving piston to be changed to a circular movement 
to rotate drive wheels. Sir Ricardo used this principle by 
attaching a pivoting crosshead to connect the piston rod to the 
connecting rod of his engine. Crosshead piston rod assemblies 

 16.54.56

file:///H|/Modellismo/AFV%20Interiors/[armor]%20-%20AFV%20Interiors/afvinteriors.hobbyvista.com/mkv/mkv2.html (5 di 7)25/05/2007

background image

file:///H|/Modellismo/AFV%20Interiors/[armor]%20-%20AFV%20Interiors/afvinteriors.hobbyvista.com/mkv/mkv2.html

transmit the reciprocating piston motion into rotational 
crankshaft motion, and since the vertical piston motion 
provides no side thrust on the cylinder walls, the rings last 
longer and there is very little oil burned, producing very little if 
any smoke during the running of the engine.  
 
This is a sectional model of a Ricardo tank engine and shows 
some of the features of this engine. Unfortunately, the 
crosshead connections of the piston rods are lost down behind 
the handwheel that rotated the crankshaft in this working 
model. But you can see that both the intakes and exhaust valves 
are on the same side of the combustion chamber, intake from 
the top and exhaust from the sides.  

 
 

Picture 10: 
In this IWM photograph, notice the front hull machine gunner's open over-head hatch (which the driver could also 
use) and another other open roof hatch further back on this tank. Many British tanks were lost due to the mud during 
combat at Messines, so in the summer of 1917 rails were added across the top of tanks like this Mk.V* for attachment 
of an unditching beam. When the tank became bogged down in mud, the beam could be chained to the tracks on the 
roof, and the beam would be pulled down the front and underneath, where the additional traction it provided might 
assist the tank to extract itself. The rear roof hatch was helpful in getting access to the beam to attach the chains and so 
were the two hatches in the roof turret. Recall that there are no track rollers along the top of the track run; the tracks 
slide along rails until they drop over the front of the tank. The sliding and screeching of the track shoes along the roof 
of the vehicle probably added considerably to the noise level inside.  
 
Unfortunately, because the British Home Office insisted on using the same Ricardo engines in the larger Mk.V* as 
were fitted in the Mk.V tanks, the lengthened vehicles were under-powered and difficult to steer with so much track 
on the ground. But, the Mk.V* design was a further step in the right direction of armored vehicle design. It provided 
increased armor protection, a simplified steering system for one-man driving, and an armored troop/cargo carrier to 
accompany the tank corps, eventually leading to the development of armored personnel carriers in future years. Notice 
the red-white-red recognition markings on the front horns of the tank. These were used to identify British tanks from 

 16.54.56

file:///H|/Modellismo/AFV%20Interiors/[armor]%20-%20AFV%20Interiors/afvinteriors.hobbyvista.com/mkv/mkv2.html (6 di 7)25/05/2007

background image

file:///H|/Modellismo/AFV%20Interiors/[armor]%20-%20AFV%20Interiors/afvinteriors.hobbyvista.com/mkv/mkv2.html

those that had been captured and were in use by the Germans. The US 301st Tank Battalion also used a similar 
marking system, but it may have been oriented to identifying battalions and the order of colors changed accordingly.  
 
With so few available documents about the interior of the Mk.V* tanks, and with only a few surviving vehicles, there 
is very little in the way of reference material available about these fascinating AFVs. Should you have additional 
information concerning the interior of these vehicles, please do not hesitate to contact us and we will add appropriate 
information to these web pages as time goes by. I am grateful to the Ricardo archives for use of their engine 
photographs. Except where indicated, the bulk of the images in these pages originated from the library archives of the 
Tank Museum and the Imperial War Museum, both in England.  
 
 

TO MK.V* PART 1

 

BACK TO AFV INTERIORS HOME PAGE

 

(c) 2002, 2003 AFV INTERIORS Web Magazine 

 16.54.56

file:///H|/Modellismo/AFV%20Interiors/[armor]%20-%20AFV%20Interiors/afvinteriors.hobbyvista.com/mkv/mkv2.html (7 di 7)25/05/2007


Document Outline