As I said I'd post my to date stuff on the Mk V vents here it is (I've started a new thread as 'variations 1 was getting a wee bit long).
Ventilation was a serious problem on the Mk V tank as there was a significant flaw in its design. The radiator for the Ricardo engine was places in the rear of the main body of the tank on the right-hand (starboard) side. Large square louvered vents were positioned on either side of the hull to allow an airflow through the radiator. To facilitate this flow a large drum fan was positioned to the port side of the tank centre line and ducting carried the air from this to the post side of the radiator, having passed through the radiator the air (now warm) would exhaust through the starboard vent. Neither the fan nor the radiator was sealed to the vents (the drive chains were in the way) but the majority of air would still pass through the tank body without circulating in the part of the hull containing the engine and crew. At best this made it very hot because there was no efficient dispersion of heat from the exhaust manifold and the exhaust pipes themselves before the latter passed through the roof of the tank and into the silencer. If nothing else this would make conditions for the tank crew extremely unpleasant but worse is to follow. The heat caused expansion and distortion of the seals round the manifold, this allowing deadly carbon monoxide to vent into the inside of the tank. That this happened is attested by a number of sources, the earliest I have found being ‘The Fighting Tanks’ written around 1928/29 and published in 1930.
This situation could easily produce confusion and unconsciousness in the crew with possible long term effects of brain damage and even death.
Thus far the story seems pretty clear. That something needed to be done would also seem self evident. Several sources come up with basically the same solution – the engine was cased in and a fan powered air supply was provided, drawing its intake from somewhere near the fly wheel (the rotation of which may also have acted like a fan) blowing cooling air round the manifold which exhausted through the roof of the tank. This would have also vented any carbon monoxide fumes. Such a system would also encourage an airflow from the side vents at the rear of the tank. However I have been told that the ‘British Tank’ states that such a system was designed by Central Workshops and rejected in Britain “without trial”. This seems incredible. A modern landlord who took such an attitude with a faulty water heater would very likely find themselves facing the wrong end of a manslaughter charge.
In fact it may not be true. The Osprey new Vanguard “Armoured Units of the Russian Civil War” has an excellent exploded drawing of a Mk V tank with such a system in place and a drawing of a tank that happens to show what the roof vent would look like from the outside. Using this as a guide to what to look for I have found a number of photos of tanks with such a vent in place. I have attached these.
The first photo ‘vent 1’ is obviously taken in Britain before the tank has been delivered from the factory (it is surrounded by RNAS personnel – the RNAS were responsible for testing tanks before delivery). ‘Vent 2’ appears to be “somewhere in France” and ‘vent 3’ shows a Mk V once delivered to Estonia (not one of those from the NW Russia force). In all three cases the roof vent looks exactly like the Osprey drawing. This would strongly suggest that this extra cooling and ventilation system was introduced into the main Mk V production run at some stage. ‘ Vent 4’ is interesting as it shows a different shape in the same location, raising the possibility of more than one vent design. That this was not a piece of Mk V tank equipment from day one is clear from a number of photos showing absolutely nothing in the same position. I have also found further photos showing something in this location but these are too indistinct to reveal exactly what and I have not enclosed them.
(I've not scanned the Osprey drawings as these are only recently published.)
However I have been told that the ‘British Tank’ states that such a system was designed by Central Workshops and rejected in Britain “without trial”. This seems incredible. A modern landlord who took such an attitude with a faulty water heater would very likely find themselves facing the wrong end of a manslaughter charge.
Be cautious in applying modern standards to past events. A passenger ship today that supplied a number of lifeboats below the capacity to carry every passenger would not be allowed but the Titanic was permitted because the standards of the day allowed ships to have lifeboat capacity calculated on tonnage rather than passengers carried. The Titanic actually exceeded the specs of the time.
Centurion wrote: However I have been told that the ‘British Tank’ states that such a system was designed by Central Workshops and rejected in Britain “without trial”. This seems incredible. A modern landlord who took such an attitude with a faulty water heater would very likely find themselves facing the wrong end of a manslaughter charge. Be cautious in applying modern standards to past events. A passenger ship today that supplied a number of lifeboats below the capacity to carry every passenger would not be allowed but the Titanic was permitted because the standards of the day allowed ships to have lifeboat capacity calculated on tonnage rather than passengers carried. The Titanic actually exceeded the specs of the time.
Well not quite true, Titanic was designed for a double row of lifeboats but only a single was fitted, partly for asthetic reasons, partly because no in White Star could work out how to get passengers safely into the outside boats before launching and partly because the ships officers didn't trust the structural inegrity of the davits to handle the weight. Indeed many of the lifeboats that were fitted were launched under populated because the ships officers were following approved standards as to the safe weight of lifeboats, no one had thought to tell them that a higher grade of steel had been used in the davits. I have seen some studies that suggest that even if the extra lifeboats had been in place many of them could not have been launched before the angle of the ship was such as to make it impossible. BTW One study also suggests that if the Titanic had not attempted avoiding action (ie had hit the berg head on) fewer wt compartments would have been breached and she might have stayed afloat.
The point I was actually trying to make is that any one any time who knows that carbon monoxide is being fed into a populated space and refuses to take action to try to stop it is downright barking mad.