Landships II

T140 · Lieutenant-Colonel

MK IV airship tug

James H · Legend

IIRC somewhere on the Forum there is a post on this, with plans from an ancient Airfix Magazine or Military Modelling. I'll try to find it.

Later that same day . . . .

http://landships.activeboard.com/t39248649/mk-iv-airship-tow-tank/

-- Edited by James H on Tuesday 13th of October 2015 03:45:02 PM

T140 · Lieutenant-Colonel

Thanks James.

Some useful info there. Does look like the top was plain, no hooks or eyes etc. Some detail on the long "rod" running down the rear face but I still can't see how any of this would hook up to the airship. Probably information that is long since lost so looks like I will have to be creative in that area :)

T140 · Lieutenant-Colonel

Found one more pic and it looks like this is with airship 23 being handled by ground crew prior to be hitched to the tug. Certainly no sign of any lines from the tank to the airship.

Pierantonio · Lieutenant-Colonel

Marcos Serra (Panzerserra) from Brasil made this conversion strating from an Hemar Female tank.

Part 1

http://panzerserra.blogspot.it/2014/08/mk-iv-female-ww-i-british-heavy.html

Part 2

http://panzerserra.blogspot.it/2014/08/mk-iv-female-ww-i-british-heavy_28.html

Part 3

http://panzerserra.blogspot.it/2014/08/mk-iv-female-airship-tug-and-mk-iv-male.html

Pierantonio

T140 · Lieutenant-Colonel

Thanks for the links. Thats one of the models I have seen where a shackle has been added at the top of the tower, but I think that is wrong. On the photo of the rear view of the tank there is no sign of a shackle, eye, hooks anything. I'm wondering if the mooring line for the airship was simply attached to that rod that runs up the rear of the tower. That would allow the line to move freely up and down the rod and be quite a simple design. Think thats what I will go for as there isn't any info to suggest anything more complex was fitted.

So, better get my Takom MK IV ordered up now :)

-- Edited by T140 on Wednesday 14th of October 2015 10:43:58 AM

-- Edited by T140 on Wednesday 14th of October 2015 10:45:26 AM

T140 · Lieutenant-Colonel

And we are off. First time I have tried a Takom kit and have to say quite impressed so far. Going together well. No flash with very sharp moulding and parts fitting as they should.

T140 · Lieutenant-Colonel

Doing the roadwheels on the MK IV.........fiddly! Must write to Fosters and ask them to design tanks with fewer larger wheels ;)

T140 · Lieutenant-Colonel

Work in progress. Main hull done, road wheels all in one hull side and about to start the other. One sponson done. I've not put the chain drive in the hull sides as it can't be seen when built so no point. Also no mg's in the sponson as tank 261 had them removed.

I'm using the ready made track plates and these clip together very easily. Instructions say assemble 92 per side but having run that round the hull side it seems 2 plates too many. Strange.

Onwards and upwards :)

T140 · Lieutenant-Colonel

Basic tank built now and given a quick coat of primer. That has highlighted a couple of very small areas that need some filler etc.

Will be painting the body of the tank before the tower is constructed as that will make it very awkward after getting to the roof and exhaust etc. Colour will be a mid grey as this was a Royal Navy vehicle. Tempted to use the primer for the base colour as its close to what I had in mind anyway.

Right, off to the shop for some Plastruct :)

Pierantonio · Lieutenant-Colonel

All my Takom Mk IVs have 90 link on each track. 92 are really too much.

T140 · Lieutenant-Colonel

Ah thats interesting you use 90. I am finding 90 a bit slack. I can get 89 to connect but they are very tight, probably too tight across the top off the idler wheel. Something I need to work on .

T140 · Lieutenant-Colonel

Some pics of the build so far. Basic are done with the tower build, some details still to add but its taken shape nicely.

Got to be the most styrene angle I have ever added to a model !

thorst · Colonel

I like it very much! It's a very interesting subject, and you are doing a great job!

Granty101 · Colonel

T140 wrote:
Basic are done with the tower build, some details still to add but its taken shape nicely.
Got to be the most styrene angle I have ever added to a model !

And will you be building a scale Airship for it to tow??

Grant

T140 · Lieutenant-Colonel

I did look at that but it would be 4.65m long. I dont think my local shop has enough styrene lol.

Granty101 · Colonel

It would make an impressive model though.

Grant

T140 · Lieutenant-Colonel

Ah it would indeed but sadly a tall order for my modelling skills. Straight bits of styrene added on is one but a total scratch build like that is probably beyond me lol.

Topoff · Sergeant

Niceeeeee, Im late to the party but very nice, love what your doing with this model, you must have the patiences of a saint

Rich

T140 · Lieutenant-Colonel

Thanks Rich. As conversions go its an easy one really. I've liked the subject for a long time but only recently come back to model making after a long break. Previously I couldnt be bothered with the Emhar kits but the new ones out now are streets ahead of those. I've enjoyed building the Takon one. I am now at decision time though, where I first started the thread. Got to make my best guess on how the airship was attached and go for it. Cant put it off any longer lol.

Topoff · Sergeant

those decesions are the hardest i find. you want to get it right but lack of info makes you choose a compromise, sleepless nights ahead ha ha

Rich

Granty101 · Colonel

Use your gut feelings as to how you would attach an airship...and stick with it.

Grant

Tonys · Field Marshal

Having looked at the photes and especially the one with the bloke leaning out of the airship with a loop of rope/cable, the easiest and practical way to attach the two machines together would be something like the spring-loaded openable ring on a necklace where the one end ring fits inside the other. This could then be opened by the rope going down to the back of the tank. Such a detail would be unlikely to show up on the fuzzy photos we have.

Tony

Tonys · Field Marshal

The problem with the tug is that the gantry members are shown on George Bradford's drawings as coming down onto the unditching rails; the gantry would have to be fixed to the superstructure as the 3" x 3" unditching beam rails would be like a piece of cooked macaroni with the loads involved.

To give you some idea of the size of the load on the gantry, I attach a drg of the tank and airship.

T140 · Lieutenant-Colonel

Yes i have that same pic but think the scale is out a bit. Compare the front airship gondola to the tank, the tank is much too small in that deawing. Even so yes the airship was BIG. I think the tower attached to the rail and braced as it was would have been ok. Remember that the usual ground handling was with teams of men and i think the rails would have been up to it. I've looked closely at all the images i can find and all seem to show the tower mounted on the rails and not the main vehicle body. Had they done that I suspect the rails would have been removed to get them out of the way. Anyway its built now and painted. Am waiting on decals and then can finish with some light weathering. Not lots as this wasn't a battlefield machine. Will post final pics when done :)

Tonys · Field Marshal

Just checked out the drawing - they are to scale!!!

The gantry could have been inside or outside the unditching rail, but neither the rail itself nor the rail connectors to the hull could have withstood a point load coming down in the middle of the long span unless additional strong connectors at that point took the load down to the hull - I had 20 years of structural design experience and still do the odd bit of design work.

Anybody got the mass of the airship???

T

Granty101 · Colonel

So Tonys,

What you're saying, in layman's terms, (if I'm reading this thread right), is that there is a potential for the mass of the airship to be so strong as to 'pull' the tower from the top of the tank??

But if the airship still had it's engines running, surely this wouldn't happen, as the tank is only 'guiding' the airship, as opposed to actually 'pulling' it along?? The airship is still moving under it's own power.

Or am I over simplifying the issue??

Grant

Tonys · Field Marshal

Assuming hydrogen was used, then the Nett lift per 1 000 cu ft is 71,05lbs.

This gives an all-up weight of 30t - quite a weight swinging around on the end of a tank weighing only 27t.

Inertia would have been the biggest problem, especially when a gust of wind would push the airship around.

T

T140 · Lieutenant-Colonel

Indeed, handling it would have been "interesting"! From one pic it looks like there were still large teams of men either side on lines even with the tank, and I assume they were there to keep the airship from swaying. Even then it surely could only have been brought out on very calm days. As this seems to have been the only tank converted perhaps the whole idea wasn't that successful.

Granty101 · Colonel

Tonys wrote:
This gives an all-up weight of 30t - quite a weight swinging around on the end of a tank weighing only 27t.

If you think about old style ships anchors, the ship weighed more than the anchor, so if you replace strong water currents with strong air currents, surely the tank must have been used like an anchor, as well as a guide??

Again, am I over simplifying things??

Grant

T140 · Lieutenant-Colonel

I'm not sure what sort of wind speeds an airship could safely be handled in, whether by man power or tank, but my guess is quite low. Anything too strong and it would simply stay in the hanger. Apart from the dangers of hydrogen the weather limitations of airships was part of their demise against aircraft.

vollketten · Lieutenant-Colonel

Is there any information to suggest as to whether the tank was ballasted out of general curiosity on my part?

T140 · Lieutenant-Colonel

Not that I know if but thats a thought. Would however put more strain on the engine in terms of weight to move. The information i have is simply that it was stationed at RNAS Pulham in 1918 and that the mods were carried out there. Thats about it. They did later request a MK V to test but that was never supplied.

Lothianman · Colonel

To be not very pedantic, a functioning airship didn't weigh 30 tons-weight or tonnes-weight - it weighed nothing in operational condition. It might have had a mass of 30 tonnes, but that is not the same thing. Nor is the dynamic loading of wind on the airship (which is the actual force which the tank would have to cope with in the case of a parked airship); however, I couldn't say how big this would be offhand.

I was, actually, wondering earlier just what the tank was intended to do.

If it was intended to tow the airship around the airfield then you might have had problems transmitting the dynamic loads to the airship through the nose of the ship, without pulling the gantry off the tank or (more likely) the nose from the ship, because of the airship's inertia, unless there was some spring or other elastic arrangement along the line. Especially, as one of us said, if the driver had a bit of a jerky start.

However, if the tank was simply intended to be a mobile mooring mast, and not to drive around once the airship was parked, that would be quite different. It could be very convenient to have something of the sort that could be driven around to the most appropriate sector of the airfield depending on weather. Possibly the photos show a parked tank to which the ground crew are pulling the airship as per usual for any mooring mast?

T140 · Lieutenant-Colonel

Again hard to say as the info is sparse but it was described as a tug rather than mooring mast. There is one artists piece showing 261 pulling the airship out of the hanger. My assumption, possibly wrongly, is that the idea was to reduce the numbers of ground crew normally required to move the airship

Lothianman · Colonel

Interesting. Another logical possibility is that they used the tank for 'warping' - if you are warping a ship you take a cable out and fix it to something like a mooring post and then pull on the cable to move the ship forwards. The really hard work way to do it was to carry an anchor out in a small boat, drop the anchor overboard, pull on th cable, haul up the anchor when you got to it, and then repeat. Hard work for something the size of HMS Victory, but they had huge and well-fed crews!

So possibly - drive tank out to where you want the airship to go, take rope from ship to tank, walk away with rope, and pull till airship comes up to tank. Then hold airship while tank drives along another stage. Repeat as needed. I'm not convinced, not least because it doesn't save much on manpower, but it is certainly a possibility and it also gives somewhere to park the ship temporarily while everyone spits on their hands and has a breather. A good look at what the cables are doing might be s good idea.

T140 · Lieutenant-Colonel

Sadly I cant find any more images that will help there. Where and lines ran is what i was after regarding where it attached to the tug but none of the pics show that. I've decided on something now and gone with it simply to get the build done. Hopefully the decals wont be too long and I can get it finished :)

Granty101 · Colonel

Lothianman wrote:

So possibly - drive tank out to where you want the airship to go, take rope from ship to tank, walk away with rope, and pull till airship comes up to tank.

Wouldn't the airship just be able to start her engines and move herself into position? The men on the guide ropes would then just have to hold her and make sure she didn't 'over run' her position???

Grant.

P.S. What we need is someone who has actually flown, or can fly, and airship, and hopefully explain it!! biggrin

Lothianman · Colonel

Dunno. But it would depend on the wind. if the wind is not in the direction along the hangar (which last would, I imagine, roughly match the prevailing wind) then you need to keep tight control all along the length - engines and rudders won't hack it at low speed (except possibly some of the modern vectored thrust blimps). Look at the whacking great windbreaks which must be to help with this problem, in part

www.google.co.uk/imgres

I cam see how walking the ship out of the hangar to a ready parked tank, attaching it to tank, and letting it swing free could be useful. For one thing it would let the men go off to other duties, the mess hall, ORs canteen etc. etc.

T140 · Lieutenant-Colonel

I did have a short ride in the Goodyear blimp once but that was a teeny airship compared to this beast lol. Like many things from WW1 being 100 years ago now a lot of knowledge has been lost which is sad. I have emailed a couple of airship fanatics and if they can throw any more light on this then i will of course update the thread.