Sunday, September 15, 2013

SDS CENTURION REVIEW


Mk 3 Centurion at Duxford Imperial War Museum UK
in colours of the British Forces during the Suez crisis era.










Well it was a very exciting day for me when i received my SDS Centurion MK3 tank
 (it doesn't take much does it )





Beautifully packaged and presented ,the tension built.Opening the box and carefully removing the contents from its foam cradle .I looked and turned the model marvelling at the detail, then--------------------------
I though to myself this doesn't look right what have they done ?

Upon closer inspection.
The overall dimensions are very close to the prototype with 1 exception the overall length.
(more on this latter)
1/ The tracks have not been positioned poorly and have a nasty bend in towards themselves at the bottom
2/ The rear deck casting has a very nasty dip or depression in it which carries threw from the rear of the hull
    to the air inlet louvres.

                                                         Photo illustrates point 1 and 2


3/ The rear of the hull should taper in at the base but has been made straight.
4/The bottom of the turret has been raised by a piece of 1mm styrene which gives the turret the correct             overall height .But doesn't give the correct diameter at the base .This is quite large and overhangs
     the stowage bins along the track guards by about half there width on the prototype.


                                                                  Photo illustrates point 4



5/The overall shape of the turret has been stuffed up.With the angles and dimensions all wrong which  
    combine to make the wrong shape altogether.The easiest way to explain this is to overlay the model
   on a plan and you can see problems.


6/The loaders hatch(The rectangle shape below the round commanders hatch) should be parallel
    with the bottom edge of the turret.

7/Although the overall height of the turret is correct from a side view.But incorrect dimensions have been
   used which combine to make the wrong profile and wrong positions for the turret stowage boxes.
   The first angle of the turret is to sharp.Which gives a measurement of 2.9mm to the top of the stowage
   boxes ,this should be 1.6mm.
   The sides of the stowage boxes are to small measuring 2.4mm this should be 4mm.Which gives too
   much angle to the lids on the boxes.
   The bottom of the stowage boxes is too low .An easy way to explain this is that the bottom of the boxes        should be in line with the bottom of the turret rear bustle overhang.Or half way threw the pistol port.(this is    the round casting  mark between the boxes on the opposite side of the turret from the side in the picture        below)
8/The rear turret bustle dimension isnt correct being 5.7mm but should be 7.2mm from top to bottom.
   All this combines to give the model a stockier or squatter appearance than should be.
9/The main barrel appears to be to low because of the turret bustle problem .But isn't actually.It should be in    line with the bottom of the turret bustle.
                                         
                                        Photo illustrates the correct positioning of the turret boxes.
                                         And barrel positioning.
                                             
                                       
                                         Photo shows turret boxes alignment problems and also
                                          barrel to low.I have put in a new packing piece to try
                                          to fix the overhang problem.And moved the turret forward
                                          as in point 10.



                                                                    Model as supplied



  10/ The overall length of the model is incorrect which is caused by the complete turret assembly being
       positioned to far towards the rear of the hull.To correct this it needs moving forward by 3.2mm
      As in the picture below.This positioning also changes the overall appearance with the turret reversed
      and barrel in the travel lock for rail transportation .Which i suppose is the main reason for the model ?


11/ Then there's the colour which for a MK3 should have been Deep Bronze Green Gloss which on this
      model looks more like Lustreless Olive Drab

  Overall this model is very disappointing .I'm not sure how they came about the design and proportions
  given that plenty of plans and prototypes are available to get it right.
  And the pricing which is a lot more than the other available models of this tank , doesn't reflect  the
  finished standard of the model.
 



Sunday, September 1, 2013

RAAC CENTURION TANK

During the depths of the 2nd World War Britain was busy developing a new generation of armoured fighting vehicle which would hopefully remedy the inadequacies of the available armour being used against the almost unstoppable Axis tanks.
The first prototype examples where hurriedly sent to Europe to gain experience from active service conditions. But with the cessation of hostilities this was not achieved. They did take part in the Berlin Victory parade in1945.
These first Centurions where fitted with a 17 pounder gun as main armament with a mixture of Polsten cannon or Besa machine gun.
The tank was powered by a Rolls Royce Meteor 12 cylinder engine (based on the Merlin aircraft engine) running on not less than 80 Octane petrol, developing 650 BHP. Driving through a Meritt Brown gearbox with Horstmann suspension, with a 4 cylinder Morris petrol engine as a APU, the new tank weighed in at 45 ton 11cwt.
With this power plant, fuel consumption was 3-4 gallons per mile cross country or 32 miles before refuelling was required. With a maximum speed of 23.7 MPH, road range was 60 miles.
The use of a petrol engine came about by way of wartime policy to obtain the most fuel from a given quantity of crude oil. With the Royal Navy having priority for diesel, the RAF high octane aviation fuel and the army using petroleum spirit.





The new tanks original design and innovations with constant improvements including sloped armour,
cast electric powered turret, storage of all ammunition below the turret ring, high velocity gun stabilized
in azimuth and elevation, and commanders vision cupola, helped to make the Centurion one of the most successful tanks of the Cold War era with 13 different marks and production of over 4,400 units equipping many countries army's including Australia.
Australia was the first purchaser of the Centurion tank from Britain in 1950, the first shipment of Australian tanks was actually transferred to the British forces for use in the Korean conflict.The replacement Australian Centurions arrived late 1951 totaling 60 units as mark 3 versions with the 20 pounder (83.4 mm ) guns without fume extractors (type A barrel )and coaxial 7.92 mm Besa machine gun and side Bazooka Plates.
The first 2 Centurions to arrive in Australia where offloaded from the (Clan Macdonald ) in Oct 51 at the  Melbourne wharfs onto SAR FBT wagons (a modified FB) for transport to Puckapunyal.

                                                        image courtesy fof Jim Leppitt.
               

Other photos show tanks being offloaded directly onto TE wagons in NSW; complete with 2 spare barrels attached to the side of the hull top and boxed items on the engine transmission covers. These tanks would also be used at Holsworthy and Singleton.



                                This shot shows the original fittings on the front Glacis plate,with
                               3 spare track links on the left and a stowage box on the right for the
                               drivers foul weather hood.
                              






 Photo shows MK3 with type A barrels, 2 spare and the turret reversed with the barrel in the travel lock. Bazooka Plates and extended track guards as originally fitted.
Tank is loaded on NSWGR/DEPT OF DEFENCE   TE wagon. These 6 wagons where purpose built for the transportation of the Centurion tanks and maintained by the railways and could be used for any other heavy loading when not required for military workings.
The original loading method is shown which used wooden guides spiked to the wagon deck to fit the inside of the tank tracks so as to maintain the tanks position during the journey as the tank was out of gauge.And the chocking method which used a metal plate fixed to the deck with an adjustable steel wedge with tapered wooden block against the track ends to stop any movement also.
The chaining down method uses the railways mild steel chains and turnbuckles.These chains where 27 ft long and travel from one side of the wagon headstock through the chain down point on the tank to the opposite side of the head stock.
Latter on tanks would be held in position with a sleeper at the end of the tank tracks from one side of the wagon to the other.

Tank Specification

Overall Length                                  983 cm

Overall Length (gun in travel lock )    861 cm

Hull Length                                       755 cm

Overall width with side plates            338 cm

Overall width W/O side plates           328 cm

Height to top of cupola                      294 cm

Ground clearance                                51 cm

Battle weight                                 50813  kg

Colour               Gloss Deep Bronze Green

Another batch of 51 tanks were ordered in 1954 and 6 more in 1955. After the arrival of these MK 5 tanks it was decided to upgrade the first batch of MK 3 tanks to the same MK 5 standard which involved fitting of .30 Browning Machine Gun in place of the co-axial Besa, bringing all 117 tanks to the same standard.
6 x Mk 2 ARVs and 4 x MK 5 bridge layers where also delivered between 1955-1961.

Prior to this Australia was approached in July 1950 to assist with the tropical trials of the Centurion with a Mk 3 arriving in Sydney in Sept 1951 for on-shipping to Manus Island,with the trials lasting until July 1952.

During 1967 upgrades to the tanks including a .50 Ranging Machine Gun, Infra Red equipment, up-armoured front Clacis Plate and a 100 gallon fuel tank fitted to the rear of the hull. This made necessary a lengthened wire sling tow rope and moving the field telephone and first aid box to a side position.
Bringing them to the MK 5/1 (AUST) standard which is the equivalent of a MK 10 but without the 105 mm gun. It was decided not to up-gun the the Centurion as Australia had been manufacturing 20 pounder ammunition since 1955.
Not all the fleet was modified and some modifications where later removed.
Australia's involvement in the Vietnam conflict saw the deployment of Centurions starting in Feb 1968 with the railing of tanks to the wharfs in batches of 6 using the TE's for loading onto the SS JAPERIT later named the HMAS JAPERIT in Dec 1969.
The first shipments  arrived with the turret baskets detached and lashed to the engine deck of the tanks .With other later shipments showing the tanks being loaded with the baskets attached which could cause damage from badly positioned slings.All loading and unloading would require external cranes as the ships cranes where only rated at 10.2 tons.
The tanks where usually covered by a canvas tarpaulin tied down to cover the turret during transport.
Only Mk 5/1(Aust) with type B barrels where deployed toVietnam .

The lessons learnt from the deployment to Vietnam and its tropical climate and forests resulted in a number of modifications.
The side skirts were removed to stop the damage to the tracks and running gear from mud and vegetation. No shipments from Australia after late 1969 had these fitted .The skirts from the ARV's and bridge-layers were also removed.
6 barrel smoke grenade discharger on either side of the turret, lamps and guards were removed.
2 spare road wheels added to the front Glacis plate.
Front leading edge of the track guards removed.
Colour changed to Lusterless Olive Drab.(1969)
Steel stowage bins and turret lockers reinforced with US and Aust steel star pickets.
Mud scrappers made from star pickets to top of track gaurds.
Fitting of AN/PRC 25 radios.
Turret canopy brackets for shade cover (hootchie)
2 x tanks where fitted with a dozer blade attachment to become Tank Dozers.


                                                   Peter Baileys 169102 Mk 5/1 (Aust)














8 additional tanks were purchased from New Zealand during 1968 for spare parts and 1 x MK 1 ARV which served in Australia.
In 1972 10 Mk 5s in storage in Hong Kong were purchased from the UK.
The Australian involvement in Vietnam finished in Feb 1972 with the return of all equipment to Australia.
The tanks served with the Army until the arrival of the replacement Leopards during 1976.
With the Centurions final farewell from RAAC service on the 20-11-76 during the Cambrai Day Parade at Puckapunyal.
With the 50 tanks from 1 Armoured regiment on parade wearing the green-pink-brown Puckapunyal camouflage scheme.

During the life of Centurions the railways where called upon to provide the means of transporting the tanks around Australia from bases to exercise areas and wharfs for shipping.
An example from the NSW Railway Digest Feb 1964 of one of these special trains composition and routing to Clapham Junction,where they would have been transhipped to the QR system?




                                                These picture would appear to be of that train
                                     Note all tanks have been tarped. The tanks are chocked with a 2'6"
                                              piece of sleeper against the track and spiked down.


                                         
                                          The first wagon in this shot has a ARV loaded
                                 with 17 tanks in all and a FS or BS at the rear for the  tank crews.
                                                   And the VR motive power visible


                                       Notice the  sleeper used as a chock against the track on the
                                       TE wagon as from the original slide chocks.






                    This page from the Oct 64 VR Newsletter would be showing the return working of                                                         these tanks 16 ? passing over the Violet Town Level crossing.
     The lower photo shows the offloading at Seymour using a Centurion Bridgelayer section as a ramp.



       This latter shot shows tanks bound for Vietnam being loaded from BME's in Feb 1968
       Note the turret baskets lashed to the rear engine cover area and the tarpaulin cover.
       And turret reverses with barrel in the travel lock position
      The numbers on the side plates is white tape for administration purposes and would be
       left to fall of once in Vietnam.
       The floating crane Titan is being used for loading.
        




                                 And what better way to move tanks around without all the hastle
                                of running a special out of gauge train.
                                From the Colin Gray collection  42211-17 at Exeter on 9-7-1972
                                We have 2 Centurions loaded on TE's
                                 Untarped on a regular scheduled out of gauge steel train .

  
 So you can have a full blown military special or just a couple of wagons in a train giving the modeller
        plenty of options to suit the time period and their style of layout operation.

       In HO model  form SDS are producing the Centurion and TE wagons
        http://www.sdsmodels.com.au/tec.htm  
       With the BME BEX wagons available from http://www.gwydirvalleymodels.com/page/Products


                                                For my modelling I used the Artitec Model
                              http://artitec.nl/index.php/en/kits/category/bouwpakketten-h0-militair
                                    Seen here attached to a Far North Hobbies TE wagon
                                                With original chocking and slide plates




                                                             And here on a BME wagon
                                    Note barrel in travel position and shorter chocks than the TE