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John, mea culpa on the 8 hole Anson -Cheetah hub, a foolish mistake ! I can’t let go of the repurposed FR blades though ! Maybe a 10 hole FR hub from a LH tractor Bristol Pegasus…was a developmental Swordfish ever fitted with an experimental four fixed blade arrangement ? I can’t see how a single glider towing squadron with an obsolete aircraft could warrant something special in 1942. It had to be some inspired fitter casting around a stores depot, trying to make the Hectors cut more air while straining to carry gliders aloft. The closest analogy I can think of is Handley Page Heyford with single fixed blade upgrading to a piggy backed two blade arrangement to make a four blades. All within the same hub, albeit 8 hole and RH tractor. The Heyford props had thin bosses, much like the Fairey Reed arrangement.
There are some Daggers around, dug up and bruised : I think one in Ireland, one with the Napier heritage trust and Hendon, not bad for such a curious Halfordesque engineering expedition. Shuttleworth has a Rapier.
Off to the foundry – all the patterns necessary for complete tailwheel assembly.
Hector prop
Anneorac,
Another reference from a Flight ad, attached, to the prototype Hart-Hector prop, made in Weybridge, with the code Z1311/1, I think.
In your magic book of prop details, is there any engineering information such as airfoil type or any other dimensions…for either Z1311 or Z3040.
What do the numbers mean, if they do mean anything?
Are these a known known or an known unknown or an unknown unknown…
Isn’t this just time expired magnesium – square grain structure causes a clean, rapid break from a micro crack. Owners of fancy race cars just replace it after a certain amount of cycles/hours. WW2 aircraft never lasted long enough for it to be an original issue in the 40’s. It is today, if the WW2 component is nudging 75 years old, with a history of hard landings and then keen volunteers looping towing cable from leg to tractor.
Folks want to replace original mag castings with aluminium these days, but it is probably the mag casting acting as a sacrificial anode that preserved the larger aluminium structure over the decades. I can understand if a mag casting is deeply buried within a structure, but if it bolts on, it can be replaced after a certain number of hours, if you invest in the casting pattern. If the aluminium has higher mechanical strength than the magnesium it replaces, it might add a factor of safety, or it might change the way force is transmitted through a structure. The world divides into magnesiumphobes and magnesiumphiles.
You have to be German to know and love magnesium and bratwurst. An old goat of a thing like a Meteor would have DTD285 magnesium castings, basically prewar German Elektron, same as half the mass of the Luftwaffe.
What to do with the Museum static with low budget kept out in the weather? Maybe steel stands under the jacking points? The maggie is just slowly fizzing away…
Colin, a richly detailed obituary that gives a good sense of the man, thank you.
Fuel-air mixture ratio gauge ? Black dots to stop damage during nestling?
Not fussed about Dagger colour, I understand they were mostly oily black…and happy with a Dag or agger, chunks thereof. Most of it would have to be recast and remade anyway. It’s about the only thing holding back a flying Hector.
Thanks anneorac, great information. 10.9′ is similar to prop on Hawker Hind – Australian Demon for RR Kestrel, excepting it is RHT. Given engine HP and airframe, I wonder if the LHT is the same as a Kestrel RHT, in reverse.
Now what do you mean by twin FR props ? Do you mean two fixed pitch blades stuck together to make a four bladed affair, like a HP Heyford?
Given the setup of the FR props, in theory it might be possible to cross two blade elements on top of each other, and use the same hub, except one hub half spun 180 degrees…with a packing piece in the middle and longer connecting bolts….
Maybe LHT FR blades from Avro Anson 1 : 6 and a bit feet per blade x 2 = 13 feet versus 10.9′
It would have to be something cobbled up in 1940 out of bits laying around, to chop more air…
And the bolt steel is S1 – 35T ultimate strength carbon steel, not hardened, apparently
Maybe the engine mounts are MB2……:eagerness: