powerandpassion[QUOTE=Peter Garner;2043492][QUOTE=powerandpassion;2043477]
Peter,
Thank you, a generous reply. One day you should stick these photos and descriptions into the Historical Aviation University, I suspect you have a whole course available, Herr Professor. I have always regarded the making of wooden propellors to be the ultimate expression of wooden wizardry. I understand in mass production in the 1930s a steel template was made and used in a pantograph type arrangement to control the routing of timber copies.
I guess your next step was to create a 1:1 sectional drawing based on tracing out the templates, but then you are back to the tradition of hand making a prop with steel test templates as guides. I am utterly perplexed how folk achieved blade symmetry all those years ago, but I guess practice makes perfect. I think you need a walrus mustache and a pipe in your mouth to really succeed in this. I do not have the talent for this and am attracted to 3D laser scanning as it can output an electronic file that can be loaded into a modern routing machine which can then free me to wander off to a cappuccino machine to try and figure out how to operate the little breech lock mechanism to insert ground coffee, again another struggle….3D scanning was quoted at 3K by a scanning mob, so it is not cheap, but I guess this can be amortized across a number of props.
I feel like a talentless fraud doing it this way but it means that the file can be emailed across the world to serve other folks needs or ten identical props can be made in one production run, achieving some of the production efficiencies enjoyed by the pantograph approach.
I will shamelessly copy your prop cardboard template method though to create a drawing for a wishbone section inserted into the spar end of Hawker Hind/Demon wings and in fact to copy some ribs in situ within a wing that I was struggling to conjure a system to handle. I will call this the Von Garner method to apply sufficient gravitas when some kid wanders over to ask me what I am doing. I am much obliged. In your photos I am also amazed at the fraulein that just keeps staring at you with those loving, never shifting eyes, an aviation buff’s ideal woman, silent and uncomplaining !
powerandpassionAll RAAF Hawker Demons (1935) were supplied with message pick up gear a close visual match to the picture of the Wirraway. I haven’t heard of Wirraways specified with this feature so wonder if this was a piece of equipment taken from a Demon and ‘tried out’ in the Wirraway where appropriate. No doubt radio would have rendered the message pickup gear obsolete in a frontline aircraft winding its way through jungle valleys in 1942.
Maybe this is in fact an arrestor hook for deck landings on the roof of a pub serving beer. This would be more consistent with much tactical thought, then and now.
powerandpassion[QUOTE=Peter Garner;2043419]Thanks for your reply powerandpassion,
Peter,
On your previous posts on Ha51, a remarkable project, how has this progressed ? I would love to tap into your knowledge of tube supply. The reverse engineering of the prop is something I would love to learn more about. One thought was to use 3D laser scanning, but you seem to have worked out a traditional approach. I often wish that this knowledge could be either recorded on video or by written word and lodged in an internet based ‘historical aviation university’ for posterity. The use of 3D paper templates on the fuselage is a fantastic idea, I’ll copy it and call it a ‘Garner’ ! I am interested in 1930’s British metal aircraft – Hawker biplane- the parallel development of the Ha51 is interesting in how different designers evolved their ideas.
powerandpassionHi all,
can someone here telll me if the Gypsy Moth and the Tiger Moth had identical wing ribs or the same profile?
Thanks
Pete
From ‘Magnificent Enterprise” by Janic Geelen ,pg 60 (NB, get this book from NZ Aviation Press, well worth it) :
How the Tiger Moth was Born.
The Moth Trainer (DH60GIII) was modified to satisfy the RAF…they wanted better access from the front cockpit. The problem lay with the wing struts that surrounded it. …they could solve the problem by moving the centre section of the wing forward…so that all four struts were now in front of the cockpit. By now, the upper wing was so far forward that the centre of lift was in front of the centre of gravity, which would make the plane uncontrollable. The solution was to move the centre of lift back…the wings were swept back..by 9 inches, 2 inches more on the upper wings. The test pilots criticised the small gound clearance of the wingtips, for with every degree of sweepback, the wingtips came closer to the ground. The solution was shorter interplane struts, which raised the lower wings. (They) produced a biplane that was not only distinctive, but also superior to any of the Moths that preceded it. The Tiger Moth was born.”
So essentially a Tiger Moth has Gipsy Moth wings swept back. An existing set of wings had the rear spar cut down and the wing was re-attached. The ribs on a Tiger Moth are therefore at 9 and 11 degrees to the direction of travel, which costs some airspeed, but cheaper solution than re-engineering entirely new wings. So the wing ribs are identical. (NB – Get a second opinion.)
A very lovely old gentleman in Bendigo, Australia made up some ribs that allowed one set of unique Tiger Moth wings to have ribs at 90 degrees to the direction of travel, giving an extra 10mph of airspeed. Rib formers are sitting in an old shed, waiting for a lover. Old bloke tore up his LAME qualifications when he got sick and tired of annual paperwork requirements. Didn’t know how to change the door on a Boeing, but could build Tiger Moth wings standing on his head. Now in heaven arguing with Angel Ministry for more sweepback on Gabriel.
powerandpassionI can help with a few bits, PM sent
powerandpassionHope that helps a little.
Great post and thread.
Type 5/17 has radium in it (AP 802 1922), dry 5/17 should be treated as if dust contains deadly biological agent.
I have P2, P3 and P4-11, waiting to devise safe handling method. Currently stored in vented safe as radium decay creates radon gas, an unhappy gas.
Filling compass with water (or high water content gin) will setup electrochemical corrosion – brass case will act as cathode to cadmium and steel component anode. Insides will turn to mush. If it is for display, perhaps leave it dry. Drink the gin.
Thinking of this safe handling method :
Tank filled with clear, water miscible oil, tank has sump to clear sediment.
Open compass under liquid bath – no airborne dust hazard.
Use air powered dentist drill to grind off radium components.
Radium Specific Gravity is 5, oil is 0.8, radium will settle to bottom.
Alcohol with micro radium particles will bind with water miscible oil, allowing full float sink separation of radium solids over time.
Proper disposal of sump sediment via medical imaging radioactive waste disposal.
Should set this up with govt grant as a Health initiative before govt spends ten times as much confiscating my and your instruments.
Original technical manuals are unsuitable as they do not envisage dealing with near century old radium binding components.
Not an issue then, leaving a legacy of passivity now. If senior members are nonplussed, why should you be ? Asbestos, anybody ?
A love of history should not expose you to a dismaying danger.
Get together, pool your resources and set up a local, govt endorsed, safe handling method.
powerandpassionSweet thought
[QUOTE=powerandpassion;2015981]I am trying to learn about 1930’s steel aircraft construction. The more I read the more I think that sacrificial magnesium anodes should be stuck to historical aircraft as good preservation practice.
By golly I had another thought ! Use sugar as a cheap aircraft preservative ! I am thinking airframes stored in the open, with difficult to access sections where corrosion sets up, where trickling water from condensation may pool and over the years accelerate corrosion. The use of silica crystals as a moisture absorbent is well established practice. But this stuff is expensive, and regenerating the silica requires treatments with dehumidified air or oven. Mainly it’s expensive. Silica absords small amounts of water slowly and releases small amounts of water slowly. You really want something greedy for water that will also release it fairly readily, like a kid with a potato chip.
Take a food technologist out on a date and ask them the explain ‘water activity’ in food science. Ie , why a moist food like jam can sit on the shelf and not go off. Sugar in jam acts as a humectant, binding water molecules to it, making them less available for bacteria to grow, ergo low water activity. I guess the same principle will act for metal. Find where water pools in a static airframe and pour a pile of cheap sugar in the spot. The sugar will grab at water molecules faster than any possible reaction of metal with the water. On a warmer day the sugar will release the water molecules and the cycle can regenerate day -night. I cannot see the formation of any chemical reactions between sugar and metal, that may harm the metal. Salt is also a humectant in its food science application, but will set up an ion pathway for electro chemical corrosion. Maybe some ants will come in.
I will have to think up a test and control to prove or disprove this sweet thought.
So folks, sacrificial magnesium anodes outside and sugar inside, how to save a neglected airframe for five bucks.
I cannot help you with home remedies for getting earwax out of old headphones.
powerandpassionNo limit except human
[QUOTE=tftoc;2038205]The recent recovery of the Do 17 has got me thinking about how much time the remaining wrecks around the world from the 1940s and earlier have left that they can still be considered a source useable components for an airworthy restoration project
Are we close to the point where galvanic corrosion on salt water wrecks has rendered all metal components unusable, even for patterns? If not then how much time is left on the clock? (And no, the data plate doesn’t count.)
There is a technical answer and a human answer.
Technical.
Bronze age artifacts remain and gold from ancient Greece remains. Very few metal aircraft will remain because their metallurgy will not support it. Duralumin is a mix of copper and aluminium, one eating away at the other, so intergranullar corrosion will accomplish in a century what we were originally injuncted to do ” beat the swords into ploughshears”. The mania for originality in parts is technically supportable while stocks of spares remain and metallurgy remains in a safe state, but a new generation of custodians needs to develop a practical philosophy towards regenerating the DNA of historical aircraft. My tuppeny’s worth is that where modern metallurgy exceeds the performance of decades old metallurgy the modern material must be used in preference to original metallurgy, simply for the sake of longevity, and thus safety. Technically, every aircraft must use silicon aluminium prior to 1930 to be ‘authentic’, but why, when it is unobtainable and will turn to powder very quickly. Technically, most British aircraft must use Duralumin through to WW2, but why, when Alclad will last 80 years longer. If I am to invest 100 man hours in a part, I would like to amortize its longevity across 200 years, not 50 years. There is really no limit to replicating parts on an aircraft, so no reason why an aircraft cannot last 1000 years. I understand that my own DNA is replicated every day, so I am not the same charming, good looking, slick dresser I was a day ago, but a copy. Still 100% “full of it” authentic but !
Human.
Aircraft are complex mechanisms beyond the powers of one individual to create, let alone recreate. Governments originally collectivised national resources and harnessed many individuals and enterprises to create a finished product. While, in the last 50 years, it was possible for an individual to amass the spare material consequent to this collectivist effort, it was possible for restoration/preservation to be a glorious extension of meccano or lego work. Need a new bakelite distribuor cap, take one off the shelf. An individual can do it. Need to make a new bakelite distributor cap ? Whoa ! The model of the eccentric individual in historic aviation preservation, as wonderful as they are, needs to be supplanted by the collectivist, working with like minded individuals to recreate a finished product, an amalgam of complex manufactures. Specifically, where you make one part, make 100 in the service of history, and network to distribute them. In turn, the network will supply you with what you may need. Unless this transition occurs all these wonderful mechanisms will fall silent as all the mass of anonymous parts under the skin become apparent. Hydraulic systems, high voltage ignition systems, pneumatic systems, braking systems, metallurgy etc. What really worries me are all the drop hammers, casting plants, heat treatment plants, steel manufacturers etc closing down. The ability of ‘short run’ , interesting historical engineering projects to be slipped in by sympathetic businesses between the manufacture of refrigerator trim and car parts. It’s like a closing door that desperately needs a realistic reappraisal of the human attitudes in historical aircraft restoration. Unite or perish, comrades !
powerandpassionKestrel Kid
Is it possible to still get manuals for the RR Kestrel V engine?
We have one at the Sth Aust Aviation Museum, which we are trying to get to run, but are in desperate need of the maintenance manual.
Any information on who to contact would be greatly appreciated.
I have Kestrel V manuals, clearances, BTH SC 12 magneto info, plenty of photos of RAAF Kestrel setup in Melbourne, happy to come over from time to time and help get it running, sigh for a Kestrel
powerandpassion[QUOTE=powerandpassion;1961275]Mike, if you have been staring at Demon panel pics for a long time have you figured where the hand starting magneto was situated ?
Answering my own question, finally confirmed that Hawker Demon had a hand starting magneto on the port side of the engine linked by chain to the engine crank handle operated by ground staff. Chief sat in pilot’s seat and flicked hand starting magneto switch on while two ground bunnies stood on wheel as per photo (State Library Victoria), inserted crank handles and turned the engine over. Even though a Huck’s starter clutch was fitted on the prop boss I have never seen photos of a Hucks starter used for RAAF Demons.
From this experience of cranking Hawker Demon engines the famous Aussie roast spit BBQ tradition evolved. A true delicacy is the famous kangaroo spit roast with tender joey in the pouch.
powerandpassionA big cavil
I am also unable to cavil at it.
This is like Adam’s navel : Could he have a belly button if he did not come from a womb ? Thus the figleaf is not to cover his goolies but to shroud an argument that theologians have been unable to answer in 2,500 years, as I guess this question over whether a desperate and cruel fascist government had a bomber buster. Who cares about Mustangs, when it’s the B-29s that are making your buildings and railway wagons do somersaults through the air ? Could it pot a B-29 ?
When I was a child I thought like a child. So when I rode my bike I thought the Kawasaki Hien Ki 61 Tony was the thing. Subsequently I learnt that the sole supply of Japanese bauxite in the Dutch East Indies was pretty much choked by 1944 by US island hopping strategy so the Tony and its ilk had major metallurgical problems. For this and other similar reasons, it was a good looking concept that didn’t deliver many bullets, thank Jesus H Christ.
Also the Bushido thing meant all the good Japanese pilots were too tough to wear parachutes until late in the piece, so the Shinden would most likely have been driven by a scared 16 year old kid, struggling with a lack of climb power because of rotten coal based fuel dug up by starving prisoners, with a vibrating powershaft because Sweden was too far away to smuggle in bearings with decent metallurgy.
You have driven me to acid thought by being based in Shanghai. I am sorry but I have seen too many bad Chinese movies with cold eyed Japanese Army lieutenants cause a Chinese peasant to be skinned alive to balance against the undoubted engineering curiosity of the Shinden. I always thought it was a Heinkel design abandoned because you would get a haircut when baling out. This wouldn’t matter if it was always meant to be a one way trip which is why it probably became feasible in Japanese military thinking.
Dig deeper dude for impressive Japanese engineering. Read Jiro Horikoshi’s history of the design of the Zero, which really did create fearful chaos. Shinden is all Hip Hop, mouth and attitude, Zero is walking into a freight train.
By 1944, it was all over, as everyone knew except Japan. The Shinden would be most effective melted down and incorporated into munitions or components for something like the Raiden as a reusable platform and anything else with wings as a one way platform. One way jobs were disproportionately effective – the only real air deterrent in 1945. What a terrible time to be Japanese and sixteen, suckered into a one way Shinden with doubtful engineering and a sashimi bale out.
powerandpassionGuess
[QUOTE=Bulldogbuilder;2035896]Can anyone explain when,why or how the “S” was introduced into the engine designation of the Wasp engines?
Guess :
Being 1931 it was the transitional period from unsupercharged to supercharged as standard, as existing engines were adapted for altitude performance. Therefore 1931 literature, probably conceptualized in 1927, would have a foot in both camps. Probably an unsupercharged engine was was not commercial/in the race by the time 1927 tooling and assembly lines were financed, designed and commissioned and all engines came out supercharged. Bit like cooking pasta for yourself then Nigella Lawson knocks on the door looking hungry so you have to add some basil pesto to the original dish concept, though the literature on the side packet just said “add water”.
I am more familiar with this theme with the Bristol Jupiter- Mercury- Pegasus rather than this clumsy Yankee theft of ideas called the Wasp, but no doubt somebody in a 16 gallon hat at P&W would have slammed a cigar down on a desk in 1931 and said, “Dammit, we’re just gonna have to makem all with superchargers then!” and a guy that looked like a thin, scared bartender in a Western would have scurried of and written the equivocating paragraph.
There seemed to be this market segmentation at the time between flying boats (unsupercharged), transports (mildly supercharged) and fighters (blow the bolts off), so any prudent scale manufacturer would want to assure each segment that their tool could do the job. I can’t think of anything further to add so I am off to cook some pasta and wait by the door.
powerandpassion[QUOTE=Bulldogbuilder;2034812]P&P and Bob T.
On a serious note……..how can we collate and have access to all our drawings?
A few problems and some ideas on solutions :
1. Bibliography of surviving aircraft drawings, ie what exists and where. This would either require a dedicated individual producing an index, unpaid and only truely rewarded by the muse of history, who will refill your glass and massage your feet in the afterlife. The internet has opened up a new opportunity where individuals may contribute to a bibliography, very much like this thread – maybe cleaned up to bare facts it can become a sticky. Another idea is to use Wikipedia, add your own ‘Surviving Drawings’ section to an aircraft description.
2. Preservation of drawings. As a minimum, make a will for drawings, so that your executor knows that the ‘boxes of rubbish’ can be placed with a ‘second’ or institution that will ensure their preservation. Practical preservation implies access, ie it is no use putting boxes into an institution or paradigm that does not have the resources to make them available, in the service of curiosity or history. The real problem with museums and most of us acting individually is that we simply do not have the resources to index or make accessible datasets originally created by drawing rooms staffed by hundreds of original scribes. Let us accept that the best resource is the passionate custodian, you, who derives great pleasure from understanding different bolt head markings or weeping over the discovery of the drawing of an obscure bracket from the passion of choice – I do ! So what we have are museums with (hopefully) a public access culture, professional storage capacity and a room with a desk and a $100 scanner. Then we have individuals who for the price of a biscuit would happily sit at that desk and sort, scan, index and even assist in answering requests on a particular aircraft from time to time. How would such a happy union be created ? Maybe the global diaspora of propellor heads needs to form a kind of internet cemented college around particular aircraft, adopt them in a sense, and adopt the idea of a project to index and make accessible the drawings. Crowd source the finance to support one or the other in a group to go after datasets close to them for a particular aircraft. Perhaps a group of ten people could chip in $1,000 each in ten installments over 5 years to allow the digitization of drawing sets by one soldier, which then sit on a memory stick in ten pockets, preserved, protected from flood, bushfire and divorce and utterly accessible for ever. Ie – fork out $100, get 100 digitized drawings on a $5 memeory stick in the mail some time later, do this ten times, end up with a full set in your pocket. Maybe this utopia might only ever work out for one aircraft, but that is one more than zero. I would be happy to participate in such a concept for historical aircraft metallurgy (DTD Standards, historical British Standards, historical US standards -what about German, French, Japanese, Russian ?), 1930’s Hawker biplane (Demon, Hind, Hartbeeste, Audax), Bristol Bulldog and DeHavilland Mosquito. It might take 25 years to do it, why not ?
3. I can’t think of a point three, but management texts recommend three bullet points. Oh yes ! The concept needs to be distilled down to a catchy corporate identifier, a flag to gather under, you know, “Overlord”, “Barbarossa”, “Desert Storm”, yadda-yadda. Something sexy. Operation Holly Shiftwell ?
powerandpassionThank you !
Every good wish,Sincerely,Richard B. Pape.[/QUOTE]
What a great, great read, thank you !
Australian telephone directory shows a number of Papes in Canberra
If he his underground I will leave a Tetleys on top. If he is above ground I will organise a Tetley’s tanker.
powerandpassionSpieler 2
Did this professional journalist let a good story get in the way of the truth?[/QUOTE]
A further 24 hours and my sub conscious has been kinder to Pape than my conscious. I guess WW2 intruded into a generation of that believed in ‘never explain, never complain’. Consequently men ( really twenty year olds ) returned to homes after the war and got drunk, cried out in terror in the night and filled living rooms with a terrible silence. Pape was a gabby self promoter who actually offered a glimpse into the experiences that damaged the psyches of a generation of men who were constitutionally incapable of communicating the perplexing mix of fear, horror and elation in combat. For the folk that weren’t ‘there’ and were trying to understand their loved ones, he opened a pretty readable doorway. I sense the war generation needed him and resented him at the same time for his gabbiness. Thousands bought his books, so he must of filled a pretty powerful need at the time. He is also readable. A bloke’s Mills & Boon. Thanks Pape, you mouth, have a beer.
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