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so lets talk 1:72 beaufighters what the issues with which


brewerjerry

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BTW the short tailplanes are identical to the Beaufort ones.

Hi

yeah most of the rear fuselage/ tail is the same as the beaufort and apparently a lot of other things are as well.

handy as I am using a donor beaufighter to help build a vacuform beaufort in 1:32

cheers

jerry

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Beau tailplanes started out short and flat and ended up (TF.X?) long and with dihedral (canted up from root to tip). I don't know if there were intermediate stages (ie dihedral and short) but I'm sure someone can tell us.

regards,

Martin

IIRC (I'm without my references ATM), the chage from short span to long span tailplane occured during Mk.VI production so it's possible to see early Mk.VI's with the original short span and later ones with the longer span tailplane with dihedral.

Regarding the Hasegawa Beau', I always felt it was overpriced for what you got, when it came out you could buy the Tamiya 1/48th kit for only a few quid more, I remember being completely underwhelmed at the level of detail in the cockpit and wheel bays (the surface detail and airframe are great however) - fortunately Aires have come to the rescue here but I've always been loathe to hack about what is still a relatively pricey piece of plastic to get all that to fit which means it remains in the stash!

I'm one of those hoping Airfix will replace their aged current Beaufighter with a new kit, I wouldn't wince at hacking it about if needed!

Wez

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I'm one of those hoping Airfix will replace their aged current Beaufighter with a new kit, I wouldn't wince at hacking it about if needed!

Wez

Wez,

Great idea! You should suggest that on the Airfix 2014 thread . . . :winkgrin:

regards,

Martin

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I thought you might like to see the differences between another contentious area on Beau kits: the cowlings.

P5040177.jpg

L to R: Airfix, FROG, Airfix Halifax, Matchbox and Aeroclub.

It's possible to get a reasonably shaped cowling by cutting the front off the Matchbox version (at the rear 'step'), glueing on one of the spare collector rings from a Hasegawa kit and wrapping the sides of the cowling in thin styrene sheet. That's what I used on my build of the Airfix kit. Of course, if you do that, the nacelle looks very 'wimpy' and I built mine up with milliput. Doing that of course emphasised that the wing is short in chord and span - a very good reason imho to steer clear of the Airfix kit.

P5040182.jpg

regards,

Martin

Edited by mike romeo
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As an incidental, what's the difference between the two other than angle?

I believe that the flat and dihedral tailplanes have exactly the same span when seen from above. However that means that the dihedral tailplanes are longer than the flat ones.

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I believe that the flat and dihedral tailplanes have exactly the same span when seen from above. However that means that the dihedral tailplanes are longer than the flat ones.

Enzo,

I'm not convinced this is true.

The flat tailplanes are ~35mm long and the dihedral tailplanes are ~42mm long (approximate - I measured using a mm scale rule from completed models). If what you are saying is true then the dihedral of the tailplane would be calculated by finding the angle whose cosine is 35/42. I did this in an Excel spreadsheet, and the angle came out as ~33degrees. I think the dihedral angle was 12degrees in reality (it definitely wasn't greater but can anyone confirm the 12 degrees number?), so I can only assume that the original statement is incorrect (I don't think that measurement error would account for the difference).

However, none of my Beaufighter references has much on the dimensional differences of the different tailplanes, so if anyone else wishes to add more information / contradict with evidence, please do so!

regards,

Martin

Edited by mike romeo
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The intention was to increase the directional stability by adding side area aft, without reducing the longitudinal stability. So the plan area would need to remain unchanged. An increase in the total span would mean a desire to improve the longitudinal stability too. Which may indeed be the case, given the additional store carriage being considered, but I'd like to see it stated in terms of aircraft dimensions rather than model parts.

In the Putnam history of the company, C.H.Barnes describes the aircraft as suffering from low frequency longitudinal instability, which was more pronounced on the tail-heavy Mk.II. A 12deg dihedral tailplane was tried on R2057, which was successful but Fighter Command thought it made the aircraft too stable so preferred to remain with the original defect (as the lesser of two evils?). He says nothing about an increased tailplane span.

My earlier understanding was that the two tailplanes were identical, except for the increase at the stub to allow for the dihedral. I'm not sure that's correct.

EDIT: Aircraft of the RAF since 1918, Owen Thetford says 12deg

The British Fighter since 1912, Peter Lewis ssays 12 deg

These three sources are from much the same time, late 50s.

In the more recent The British Fighter since 1912, Mason says 15 degs

Edited by Graham Boak
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I'm not convinced this is true.

The flat tailplanes are ~35mm long and the dihedral tailplanes are ~42mm long (approximate - I measured using a mm scale rule from completed models). If what you are saying is true then the dihedral of the tailplane would be calculated by finding the angle whose cosine is 35/42. I did this in an Excel spreadsheet, and the angle came out as ~33degrees. I think the dihedral angle was 12degrees in reality (it definitely wasn't greater but can anyone confirm the 12 degrees number?), so I can only assume that the original statement is incorrect (I don't think that measurement error would account for the difference).

Dunno where I picked that up from, but I reckon you've quite conclusively disproved it. Mind you, I had to go and check it myself. I thought that you might have forgotten that Excel works in radians rather than degrees. :smartass: Turns out that you hadn't... :lol:

The dihedral of the tailpanes is quite clearly around 12 degrees. No way is it 33.

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I thought that you might have forgotten that Excel works in radians rather than degrees. :smartass: Turns out that you hadn't... :lol:

Enzo,

It did take me a while to get the equation right in Excel. :) I don't get the opportunity to do much Engineering maths any more . . .

regards,

Martin

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Un-scientific measuring of original Frog tailplanes gives the lengths 35mm (straight) and 40mm (slanted). Using arc cos 0,875 as Martin above it gives about 29 degrees of elevation. What it actually was, I don't know but that was how Frog saw it :-) V-P

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I don't get the opportunity to do much Engineering maths any more . . .

That's a shame. Engineering maths is just so much fun! :D

I love maths! My job is as a commercial trainer but my dream job would be teaching degree level maths to mature students.

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That's a shame. Engineering maths is just so much fun! :D

I love maths! My job is as a commercial trainer but my dream job would be teaching degree level maths to mature students.

That does sound interesting! Teaching motivated and enthusiastic students; that'd be a buzz!

By preference and experience I am an aircraft performance engineer, but I mostly act as a technical reviewer these days, asking the bright young things, "the difficult questions" about their results. I can guess what they think . . .

regards,

Martin

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