Hurricane XII Propeller

Thats right Baz , shortened ( and obviously reprofiled to suit ) Lancaster blades . A guy who flies at our RC club works for SAFE and said it gave him the ” willies ” cutting the tips off servicable Lancaster blades with a band saw . I think he said it was 6 inches off ( but it was ages ago , so dont quote me on that ), and I think I recall him saying that they did 12 in total . Not sure if the extras were for spares , or a different project alltogether .

The recently rebuilt Mosquito used modified (shortened?) Lancaster blades as they didn’t have enough servicable Mosquito ones. Not sure about the hubs.

The only difference between the 23-E-50 and the 23EX is that the inner bore of the spider is splined to fit a No.5 British shaft and the seals are a little different. I must admit i was not aware of the exclusive use of the No.5 shaft on all Canadian built Merlin powered aircraft. I had always thought that in Canada they would have SAE 50 shafts as they mostly used Packard built Merlins. Do operators today use the 23EX?

BBMF Lancaster has Ham standard 23EX hubs, not sure about the mosquitoes that are flying but i would think Ham Standard would be a logical choice given the spares availability. I believe the bore is almost the same as the american shaft but the spline profile is slightly different, but i wouldn’t swear to it. I think the 23EX hub gave interchangeability of the prop assembly across all applications. I have always wondered if it is possible to change the prop shaft or the reduction box rather than the spider? That way a British Merlin could be flown with a Packard prop shaft and a standard 23E 50 prop? Hamilton standard nomenclature demystified here for those who are interested;

http://www.enginehistory.org/Propellers/HamStd/hamstd.shtml

The only difference between the 23-E-50 and the 23EX is that the inner bore of the spider is splined to fit a No.5 British shaft and the seals are a little different. I must admit i was not aware of the exclusive use of the No.5 shaft on all Canadian built Merlin powered aircraft. I had always thought that in Canada they would have SAE 50 shafts as they mostly used Packard built Merlins. Do operators today use the 23EX?

Most enlightening! Where do you find a 23EX life ex spider nowadays??

They are pretty rare but I would enquire with one of the hurricane operators. They may have an uservicable spider?

Most enlightening! Where do you find a 23EX life ex spider nowadays??

Hi David it is actually a 23EX hub. The difference is the spider which matches the British 50 spline profile. The parts (other than the spider) are interchangeable with the 23e hub i.e. C47. The same applies to Lancaster and Mosquito. The difference being the blade profile. Incidently the ‘E’ represents the blade shank size. i.e. 12D being a Harvard hub with a D shank.

Thanks Ollie !

Yes. Hamilton Standard 23-E-50 as used on several types of aircraft.

Brilliant ! That helps a lot!

Not sure if this will help you, but checking through the CAA ANN’s for the currently airworthy Hurricanes fitted with HS props, it would seem that the prop types fitted are either the 23E50-505 with 6353A-21 blades or the 23E50-459 with 6353A-20 blades.

And also, here’s a paragraph from the AAN (Issue 3) for HAC’s G-HURI :-

The propeller fitted is a Hamilton Hydromatic Type 23E50-481-6503A-3. (Air Ministry Type A5/131) The Constant Speed Unit is a De Havilland AY122. BAe Hatfield have confirmed that this is an acceptable combination for use on the Hurricane.

Issue 3: A Hamilton Standard Propeller type 23E50-473-6503A-3 was fitted to this aircraft at initial permit issue. Reference to the 23E50-481-6503A-3 is therefore incorrect. Hamilton Standard have confirmed that 6503A-3 propeller blades are acceptable for use with the –473 propeller. The 23E50–473 propeller differs from the 23E50-505 propeller fitted to Hawker Hurricane G-HURR, AAN 21948 refers, only in the propeller dome assembly. This change is considered to be minor and the Hamilton Standard 23E50-473 propeller is therefore considered acceptable for use on this aircraft.

Cheers

Paul

Interesting to know ! Can anyone give any clues on blades?

Static Merlin Hydromatic Hub

I’ve got one available – but I’ll not be letting it go cheap as its a nice one.

P/X acceptable:D

Anon.

Are CFS Aeroproducts still around? They might be able to help

I don’t know, but somebody here will know!

You could ask HAC as their Hurricane has one.

Thanks ! -Are these readily available for statics ? – I cannot remember where they are sourced from .

The exact spec….or is just that it was a Hamilton Hydromatic VP of 10’8″ ?

I will have exact reference but needs a bit of searching.