Mike, we should start some kind of society – I agree, props never got the attention they deserved – even during the design stage.

Enormous amounts of time and energy were spent refining engine designs to get maybe a couple more horsepower here or there with every tweak – half a mile an hour’s worth of new valve seat would be incorporated with alacrity.. and then the aircraft designer would almost chuck any old prop on the front. As long as it fell within a power range and didn’t touch the ground, it would – and usually did – do. The fact that the wrong choice could drain 100HP’s worth of thrust from the system didn’t seem worthy of consideration, and curiously only rarely has since. It is only now that Hercules propellers in Gloucestershire are showing GA users the enormous difference the right prop makes.

Serious amounts of work went into designing blade profiles and aerofoils on both sides of the pond and even more (as shown in the video) precision-engineering these within an inch (or a Thou) of their lives. This was then completely ignored – as long as it goes round the right way, it could all be forgotten.

A classic example is the Whirlwind – the bleedin obvious (when you see it) problem with the wrong blades wasn’t seen, to the point where it ‘must’ have been some unspecified and untraceable problem with the engines – and that is what passed into the record. I am uncovering several more cases like this.

Really excellent piece of video.

..but interesting comment from a US You-Tuber – “Trashed one of our planes. What were they doing in England anyway”? Is this a common thought in the US about warbirds in Britain? Interested to hear from Americans.

Amelium

– Something that cannot be found but at the same time is exactly where everyone thinks it is (e.g. Pacific Ocean, Dartmoor). Often used in aviation.

Fool’s Amelium – a common name for Gillespium. Gillespium may be distinguished from Amelium by being a) found and b) misidentified.

Great footage – so good to see high resolution images from the Battle, with sound, and which are not the same few seconds repeated endlessly on TV documentaries over and over again. Is this part of the new IWM release?

One thing – the title is misleading, it looks like someone has spliced a Polish Hurricane squadron in with 19’s Spits. What’s the etiquette for asking for YouTube titlles to be changed?

The max rated continuous HP of a 6167 on a 3D40 / 3DX is 825hp, and 909hp for take-off according to the FAA TDS. http://rgl.faa.gov/Regulatory_and_Guidance_Library/rgMakeModel.nsf/0/7b0e7371b1979abf8525670f00671430/$FILE/ATTKC5QH/Hamilton-3d.pdf

The 6101 is 850 / 1,000 which puts you even more centrally in the ballpark. Don’t be distracted by hub designations, of course – the blade at the hub end is described by the shank size only (D), in that it affects the profile at the root.

In reality you could use a 6101 blade profile, trimmed by six inches.

If we discount the 6167 as its max continuous is less than the max rated output of the A74 then nothing fits exactly on the Hamilton side. Unless they did what DH did in some cases – took a ‘cropped’ HS blade and called it a new base design – in which case to create an ‘authentic’ blade rather than one that works (6101-6) we are in the land of looking at photos and comparing unless the Fiat documentation describing just what they did back there can be found.