Hawker Hurricane by John Timmis

[John Timmis]

Hi everyone, I've been meaning to do this for ages. This is follow on to my Chipmunk build. So, having survived the Chipmunk experience, this is my attempt to raise the bar a little higher & to try & apply some of the lessons learned.

The chipmunk build was nearing completion & I was starting to think 'What next'. At this time I met Danny (Greenacres 15) & during the conversation about Chippies I said that I fancied a Hurricane next. He produced, from the back of his car, a fabulous Hurricane. 'You would enjoy one of these'. So the decision was made there & then, a Brian Taylor Hurricane, encouraged (egged on) by Danny Fenton. Magic.

This will not be a blow by blow description of the build. I an already well on the way with the construction. The build started in January, the Chipmunk was finished, apart from painting but the workshop was too cold, so the Hurricane build began.

These photos show where I am now. Next time I can show some of the steps along the way.

Cheers John.

[Phil 9]

very nice indeed

[onetenor]

Looking real

[Andrew Price 2]

Looking good.

[Andrew Price 2]

Tick the box next time Andy!

[John Timmis]

Hi,

The plans were bought at the Cosford show in 15. I already had a 500kv motor that should do the job using the same 6s lipos as on the Chippie. The main thing I was after was a set of electric retracts & sprung u/c legs. I've not done retracts before, that was one of the challenges.

The plans are excellent & are very clearly drawn; they do look very accurate & all the parts fit well. They are a master class in scale modelling construction. I was very impressed.

So work began in Jan. It was too cold to paint the Chipmunk.

Start on the tailplane; do the easy bits first.

I decided that I could do without the lazer cut pack & cut the bits out myself. That way I can select the wood. It takes a bit longer but if you're going to spend a year on a build, a couple of days cutting out parts is nothing.

The tailplane is standard construction for this type of model. It went together quite quickly. I had some nice 1/4 grain, 1/16 balsa that I used for the sheet core. I was keen to achieve fine trailing edges to the elevators & rudder. The only small change I made was to sand the T/E sheet away to nothing & then add a new 0.4 mm ply T/E. The plan emphasises the need to keep the rear end light so lightening holes will be done later.

That's it for now. Next time: start on the fuselage.

Cheers John.

[Colin Leighfield]

That really is a beautiful build John. The construction detail looks excellent, I can see why Bryan Taylor designs are so highly rated looking at this one.

[John Timmis]

Hi

Next up is the basic fuselage. This is all straightforward model construction. Just like a junior 60 really.

Because I'm converting to electric power, the front of the fuselage needed to be extended by about 3, 3/8".A new firewall was cut out from 6mm ply. I put in a few extra diagonal braces into the rear structure. Apart from that it's built exactly as drawn on the plan. Simple enough so far.

The Hurricane was the 1st monoplane fighter for the RAF. It was also the 1st with such features as retractable uc & eight machine guns. Despite these advanced features it was the final development of a long line of Hawker biplanes. Really almost a monoplane Fury. The fuselage primary structure was made up of high tensile steel tubes, mechanically joined together & braced internally with wires. The external shape was produced with wooden formers & multiple wooden stringers covered with doped fabric. Everything you see of the fuselage behind the windscreen is wood & fabric. Not cutting edge stuff like the stressed skin of a Spitfire, but quick & easy to make & simple to repair. Most of the bullets went straight through.

I really like the fact that the model follows very closely the structure of the original. It's good scale modelling.

The fuselage can be put aside for now & a start made on the wing.

Cheers John

[Geoff S]

It's lovely. What's the wingspan and expected final weight (a target you're guaranteed to miss ). I'm guessing 60" (1.5 metres) at the ws. I have no idea what the likely weight would be.

Geoff

[Colin Leighfield]

Those who restore and rebuild Hurricanes say that there are four or five times as many man hours in restoring or building a Hurricanr than a Spitfire, because although the structure is simple in principle and localised damage is easy to repair, it is built up of a very large number of jointed pieces that are very labour intensive in assembly. Tooling and set-up costs are low because of the lack of major press work associated with stressed-skin monocoque design and as John says, Hawker were able to build it wholly on existing tooling and equipment. Looking at some of the early Hawker design project drawings, the original Fury monoplane proposal with fixed undercarriage would make a really nice model.

If I ever do a Hurricane though, the BT version is the one for me. The photos in this thread show just how beautiful the structure is and probably similar to the full-size, time-consuming rather than difficult., I've seen Danny's BT Hurricane finished as a Mk1 and don't think I could ever have the patience to produce such a museum standard of detail and accuracy. You never know though, I might live long enough. I'd better finish the Chipmunk first. In the meantime, I'm just going to enjoy watching John showing me how to build a real model aeroplane.

Edited By Colin Leighfield on 27/09/2016 07:26:12

[Manish Chandrayan]

Lovely work there John. Watching with interest

[John Timmis]

Hi. Thanks for the comments.

Geoff. The wingspan is 70". Brian Taylor's model was powered by a Lazer 75. It weighed 10lb 2oz ready to fly but with no fuel. I guess that will be the target weight. The plan emphasises the importance of getting the C of G correct & also the necessity to save weight at the rear. It's not a model that is going to turn out nose heavy. Achieving a good weight will depend on how much ballast (none I hope) is required in the nose. At least there is plenty of room for some big batteries.

Colin. You are quite right in what you say about restoring Hurricanes nowadays. At the time, however, the Air Ministry estimated that it took 15,000 man hours to build a Spitfire & 10,000 to build a Hurricane. In other words, you could have 1 1/2 Hurricanes for every Spitfire you built. Hawker chose to stick with the known & available methods while the Spitfire was new cutting edge technology. Hurricane was the last of a long line. The right decision at the time.

Cheers John.

[Colin Leighfield]

Hi John. I'm surprised at those numbers. Once Lord Nuffield was involved and car type mass production methods introduced at the new plant in Castle Bronwich, building a Spitfire became a process really of riveting together pre-formed aluminium pressed sections. I understand that until not many years ago a big press tool was still hanging on a wall in the (now Jaguar factory), that knocked out the "D-box" leading edge pressing in pretty much one piece.

Be that as it may! That's a fantastic model you are building and I'd be proud to call it mine.

[Bucksboy]

That fuselage looks very similar to my Brian Taylor Bf 109, he came up with a winning design and stuck with it as the basis for all his models. Well, the ones of his I've built anyway. The Hurricane looks great, I was donated a half built version thats waiting in the wings for another year.

[Nigel Day]

Looks lovely John.

[Trevor Crook]

Looks great John. Are you going to have a battery hatch, and if so where? I ask this because I vaguely remember Danny building in A123 cells and charging in situ, but I may be wrong. Using "conventional" lipos and being able the swap them at the field seems more practical, but you obviously need an accessible but discreet battery hatch.

[Danny Fenton]

I dont know getting the blame for being a bad influence
I did indeed my Hurricane around 6S2P A123 cells and can charge in situ. But the top of my cowl detaches to access all the electrics and sound module.
Looking Good John

[John Timmis]

Hi Trevor, Danny.

This is an area of the model that I'm working on now. On the Hurricane, the whole of the fuselage forward of the cockpit was covered by removable metal panels, very convienient for us modellers.

The top of the cowling will be removable, the area bounded by the tape. There is enough room to hold a party in there. There is also the possibility to create a similar space under the cowling, perhaps for a sound module?

Cheers John.

[Geoff S]

That looks very neat, John. It looks like battery space isn't much of an issue. My DB Tiger Moth has a hinged hatch on the fibre glass cowl for battery access which is OK but isn't very scale looking. I'm sure you'll devise a much better solution. What motor are you using?

Geoff

[Danny Fenton]

Hi John looking good, I put the sound system under the cowl, the BEC down one side, the ESC and telem the other. Air servo and filler at the top. The air cylinders (two) were where the fus fuel tank would be on the full size. I found it extremely crowded. However if you are not using air retracts, you will win back a shed load of space by not having the tanks.

The entire build of mine was over on RCSB

Cheers

Danny

[Andrew Price 2]

[John Timmis]

Hi all

Geoff. I'm not an expert on power trains. Anyone who is please feel free to comment.

I bought the motor unused from a friend, it looks quite chunky to me. 'Thunder Tiger ace RC ripper' , OBL 50 /50A 2385. ( where do they get tha names from?). Anyway the specs say: 520 rpm / volt, max surge current 58A, recommended prop 14/8, 15/8.

I tried it out this afternoon. It showed about 840 W, but this was on a 14x7 prop & a very puffed up & clapped out Dynamic6S, 330C 4500mAh battery (all that was available). The voltage dropped to 18v under load. I think that I will probably need 1000W.

What do you think? Am I in the right ball park?

Cheers John

[Geoff S]

Well, it's certainly somewhere near. I guess you should aim for 1kw but I'm not entirely convinced about the need for 100w/lb as is usually quoted. That 100 watts was the figure when brushed motors (often cheap 600 s) were the norm and they weighed a lot, had weak magnets (usually) and, of course carbon brushes. I suppose the expensive Astroflight etc brushed motors with rare earth magnets were much better but modern brushless motors are better still and lighter to boot as are LiPos compared to NiCads/NiMh.

My Ballerina is as aerobatic as I want or need on 90 watts/lb and I rarely use full throttle. The motor draws 30 amps flat out on 4S and with 8 or 9 minute flights there's usually about 50% (or more) left in a 4000 mAH pack. I think you'll be OK with that motor if the finished model is 10 lbs as you're aiming for. Of course, with Fenton scale finishing details added it might be a bit more

Geoff

[Danny Fenton]

Just looking at that motor John, it is a 50/55 size can so not that dissimilar to the one in my Hurricane. (5065 size in mine)

However, you are using quite a high KV and a higher cell count than the specs suggest, 5S max according to the sheet I read.

I like big props at low revs, they are easier on the ear, and the props and spinner far easier to balance.

Here is the spec for a 10lb Sea Fury I enjoy flying My avatar piccy

The motor (5065 350 kva) in my 6S2P (A123 volts more like 5S LiPo) powered Sea Fury weighing 10lbs produces:
57Amps 17.22V 1014 watts on 18x10 and it flies really well.

I agree with Geoff you don't need 100 Watts per lb with the modern gear, but it is still a safe and simple yardstick.

Cheers

Danny

[John Timmis]

Hi Geoff, Danny.

Thanks for your replies, I really appreciate the advice.

Actually I made an error when entering the motor serial . It's a 2386 not a 2385 as I first said. I guess that will make it a bit better. Would you have another look & tell me what you think?

Thanks John