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By: 1st May 2019 at 09:38 Permalink
-The quick answer is that the Spitfire in the first photo is fitted probably fitted with the Bracket Type DH 5/39 prop and the RAAF examples have the Hydromatic DH 45/4 or 45/1 prop. Excellent as it may be, there are a few errors in that section of ‘Spitfire the History’. DH 5/29 and 5/39 props are Bracket Types and the diameter of the Rotol RS5/24 prop is actually 10’ 3”.
For the DH props listed against the Mk.V I can find the following.
Bracket type 5/39, 10’ 9” Diameter, DP55409 Blades, P30100A or P30110A Spinner
Hydromatic Type 45/1 or 45/4, 10’ 9” Diameter, DP454509 Blades, P30510A Spinner
None of the records I have list the 5/29 prop for the Mk.V but the diameter, blades and spinner are the same as the 5/39.
For Rotol props, the diameter, blades and spinner details are the same for the RX5/10, RX5/14 and the RS5/24.
10’ 3” Diameter, RA690 or RA10049 Blades, ES11 Spinner.
That’s not the whole story though, early Mk.V aircraft can be seen with the rather blunt spinners used on the Mk.II Spitfires.
By: 1st May 2019 at 12:00 Permalink
-Interesting, I have seen photo's of some MK V's of which the spinner has a small fixed fairing in front of every prop blade root. What's the function of this?
By: 1st May 2019 at 12:48 Permalink - Edited 1st May 2019 at 13:17
-Possibly de-icing - there was a system on some Hamilton/DH hubs feeding fluid to nozzles in front of each blade root.? Can you provide a pic?
On the subject of "Spitfire, the History", Troy, please don't rely on it for any figures. As soon as they were faced with producing any kind of table the authors appear to have panicked, got drunk and wrote down how they remembered things last time they looked. So many people swear by it, and it always seems great as a reference due to the sheer volume and level of detail but if you try reading it some glaring inconsistencies and contradictions quickly emerge. If you approach any specific part of it with pre-knowledge of a particular area, as I did with propellers, you will end up throwing it at the cat.
You will also notice that the blades on the Hydromatic-equipped Spitfires are a subtly different shape. They are actually a 4,000 series shank and a different design drawing from the 5,000 series DH props - something to watch out for if modelling an 'Australian' Mk.V.
By: 1st May 2019 at 13:55 Permalink
-Interesting, I have seen photo's of some MK V's of which the spinner has a small fixed fairing in front of every prop blade root. What's the function of this?
I think that you may be refering to this system
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By: 1st May 2019 at 13:58 Permalink
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On the subject of "Spitfire, the History", Troy, please don't rely on it for any figures........
Unfortunately this is true. It is a great starting point but, as with several Putnam's, it is worth cross-checking with other sources
By: 1st May 2019 at 18:17 Permalink
-Where is the illustration from? It's certainly an interesting subject - i'd heard of this but not seen it before.
By: 1st May 2019 at 18:22 Permalink - Edited 1st May 2019 at 18:25
-It was in Aeronautics, Dec 1939 (I think) but is adapted from the illustrations in the DH patent in the link I posted
By: 1st May 2019 at 21:50 Permalink
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On the subject of "Spitfire, the History", Troy, please don't rely on it for any figures. As soon as they were faced with producing any kind of table the authors appear to have panicked, got drunk and wrote down how they remembered things last time they looked. So many people swear by it, and it always seems great as a reference due to the sheer volume and level of detail but if you try reading it some glaring inconsistencies and contradictions quickly emerge. If you approach any specific part of it with pre-knowledge of a particular area, as I did with propellers, you will end up throwing it at the cat.
Poor cat! It's a heavy book! Actually having read so much about it on Britmodeller, I was a little disappointed when I got a copy, in part as there is the Spitfire production site, which is a big chunk of the book.
I have in the past recommended Alfred Price "The Spitfire Story"as a better modellers introductory reference!
You will also notice that the blades on the Hydromatic-equipped Spitfires are a subtly different shape. They are actually a 4,000 series shank and a different design drawing from the 5,000 series DH props - something to watch out for if modelling an 'Australian' Mk.V.
Well, this is why I asked, I can see that, I think I can also see two spinner shapes as well.
Your and Anneorac's post have been of great help, thank you.
Is there a source illustrating the various types of DH Spinners and prop blades mentioned anywhere?
cheers
Troy
By: 1st May 2019 at 22:15 Permalink
-On a similar subject related to the props, is there is 'simple' way (I'm sure there'll be nothing simple :) on the subject) of knowing what prop (Rotol ot de Havilland) was fitted with a particular airframe?
By: 1st May 2019 at 22:43 Permalink - Edited 1st May 2019 at 22:45
-The spinner shapes are different in the way Anneorac describes because of the 'architecture' of the Hydromatic hub, which needs less diameter immediately in front of the blades and slightly more space towards the forward extremity for the 'dome'
It's worth having a rummage around on here as I know there's been more than this conversation https://forum.keypublishing.com/forum/historic-aviation/142266-spitfire-propeller-question-from-mk1-to-mk-vc,
Training film here on Hydromatic props, curiously using a Spitfire: https://www.youtube.com/watch?v=fvCmQAetyag - it shows the dome that required slightly more room (and necessitated a different mounting) than the cylinder of the Bracket type.
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By: 1st May 2019 at 22:49 Permalink
-On a similar subject related to the props, is there is 'simple' way (I'm sure there'll be nothing simple :) on the subject) of knowing what prop (Rotol ot de Havilland) was fitted with a particular airframe?
For just the Mk.V ?
I suspect, without a photo, no. There maybe some 'rule of thumb' , and trends in production batches and/or where built, but I don't know if that data exists for a really accurate result.
I'd like to be proved wrong this though!
Are you the same Tony C from Britmodeller?
cheers
T
By: 2nd May 2019 at 16:19 Permalink
-Simple rule: Supermarine builds DH prop Mk.I and Mk.V, Castle Bromwich builds Rotol prop Mk.II and Mk.V. Exceptions existed.
By: 2nd May 2019 at 20:54 Permalink
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Are you the same Tony C from Britmodeller?
Hi Troy,
Thanks for your imput and yes, I am one and the same!
Posts: 9
By: Troy Smith - 30th April 2019 at 22:45 - Edited 2nd October 2019 at 11:40
Modeller question, I have asked on Britmodeller,
https://www.britmodeller.com/forums/index.php?/topic/235052956-spitfire-v-b-vs-c-wing-and-uc-details-and-prop-variants/
and in my searches, found this thread here
https://forum.keypublishing.com/forum/historic-aviation/79363-questions-on-spitfire-propellers-merged
Regarding the props fitted
this image has the first with the De Havilland unit and the other with the Rotol unit?
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Spitfire the History has this
De Havilland type 5/29A hydromatic
De Havilland type 5/39A hydromatic
De Havilland type 45/1 hydromatic
De Havilland type 45/4 hydromatic
all 10 ft 9in diameter
or
Rotol RX5/10 - 10ft 3 in diameter
Rotol RX5/14
Rotol RS5/24 both 10ft 9 in diameter
But there is also a suggestion later Vc had a different DH unit, as seen on RAAF Spitfires?
[ATTACH=JSON]{"data-align":"none","data-size":"full","title":"c6fff0fcbd98eb21187877cdf6787206.jpg","data-attachmentid":3860951}[/ATTACH]
This appears to have a longer pointier spinner, like this
[ATTACH=JSON]{"data-align":"none","data-size":"full","title":"4025479.jpg","data-attachmentid":3860952}[/ATTACH]
I'm wondering if @Mark12 or anyone else maybe able shed any light on how the maybe appear different to the eye of the modeller?
thank you
T