powerandpassion“Jacatra” or should it be Jakarta which was Batavia?
Djakarta until adoption of modern Bahasa Indonesia ‘Jakarta’. Nice Indonesian Air Force Museum in Jakarta with slowly corroding airframes, worth visiting.
I remember seeing a derelict Mitchell or C-47 in the swamp alongside Dili airfield in 1989, in what was then Indonesia, never bothered to have a look in case of landmines or unsympathetic sentries with semi automatics.
You could probably say that what is now Indonesia had the largest WW2 era airforce into the 1970’s when you aggregate the derelict airframes in Irian Jaya, and what was left by the Japanese, Dutch, Americans. Not much left now at all. Lots of Hurricanes were shot down in Java in 1942, one made it to Australia and lasted until the 1950’s before being scrapped.
As you know, the Spanish and Portuguese divided the world between them in the 15th century, Spaniards of to the Americas, Portuguese off to India and the spices of the east. Later came the Dutch East India Company and Clive of India to sort things out again. The last holdout of the Portuguese was East Timor, so you can find the ruins of 400 year old forts there covered in vines, and look at the sea and imagine the red sails of caravels leading in the sunset. The you can find old coins from the time in the local markets. So many empires and so many stories have crashed like waves on the shore of these lands, that you can understand the prosiac take of the locals towards earning copper coins from dragging the scrap left by all these adventurers out of their jungles and seas. I am sure the beachcombers and bootleggers did a fine trade when the Spanish Armada washed up on Britain’s shingle beaches.
One ‘Indonesian’ Airforce which is quite undocumented was assembled by US interests in the southern Philippines in 1957 to support the ‘Colonels Revolt’ a failed coup, based in the Moluccas, against the Indonesian central government of Sukarno. This saw Mitchells flown by alleged US pilots engaged against Mustangs flown by Indonesian pilots. It all ended in embarrassment when an Indonesian Mustang shot down a Mitchell, and the captured Mitchell pilot, against orders, kept his dog tags which identified him as a US citizen.
Probably the largest undocumented Air Force in South East Asia from the 1950’s to 70’s was operated by ‘the Company’, care of the US tax payer. Now there would be some stories to tell.
powerandpassionKnuckle
Here is another photo of the Merlin rolling stand stolen from the AWAL website in Australia. It shows more detail of the knuckle connecting to the engine foot and the intimation of some locking handles close to the base that would stop the engine – half circle assembly auto rotating. I imagine that the heads and block would be fairly easy to rotate around around a common centre of gravity designed around a bottom end dressed with crankshaft, conrods and blocks dressed with valve gear. It would be easy to rotate this by yourself but a second person was required to fix the locks that would stop subsequent auto or uncontrolled rotation.
If you were to design this in CAD you might design a simple block model of the engine, weigh the separate components to determine the centre of gravity, understanding that when you just had the bottom end in it would auto rotate to present the block retaining studs/bolts to the sky.
powerandpassionTail wagging
Another nice pattern for tail wheel assembly. Main body holding rubber dampers. All the different patterns show why you just can’t 3D print casting patterns without appreciating the job of the foundry man, or direct cast off an original component.
These patterns are not cheap, but I figure they could help keep 10 tailwheels in the air over the next two decades or so, so the pattern cost can be amortized to a tenth, making an individual casting more affordable.
It essentially locks up risk capital for decade, with the simple hope that lower cost casting propositions will eventually lead to its return. There are many better and smarter things to do with money, but no dollar bill ever directly blew the top off a Gestapo prison.
powerandpassionI understood that the lead (tetra-ethyl lead (TEL)) was added to assist in lubrication of the valves as well as an anti-knock agent. Anon.
Yes, can’t just fill’er up like I do my lawn mower. It specifies 87 octane in the books, which I can get at the local servo, but I don’t know what sort of chewing gum they put in the fuel these days instead of TEL. Luckily for me the only petrol refinery that makes aviation fuels in Australia is down the road, so I will wander down to annoy some guy in a white labcoat.
By the way, I took a handheld XRF into my front garden to test if decades of TEL emissions from the road in front were getting into my carrots. Not a super busy road, and the garden was OK. But soil from the old front fence, after being scraped of lead paint over the decades, was at the upper limit. Most exiting was the veranda where I scraped the paint off, in my bare chested, no respirator, early home renovation days. Soil was off the dial !
Out of curiosity I tested some old industrial infrastructure, say like a hangar, where rain would carry particles of paint down, and the soil at the footings would glow, if lead could glow. Don’t eat carrots grown next to a hangar. Wear a respirator when scraping old paint. Wear a respirator when blasting vintage engine cylinders. Lead apparently causes cerius menatal redardition.
powerandpassionI don’t know about older (WWII era) air cooled engines, but in the TVO-435 engines I used to work on, the barrels didn’t time expire. If they made it to overhaul, they were inspected dimensionally, NDT’d for cracks and returned to service.
Got about 30 barrels which will be dry ice blasted and dye penetrant tested, hopefully end up with 21 that will last the distance.
powerandpassionEngine Test Protocols.
I have copies of original Packard Merlin engine Acceptance tests, which ran for up to 10 hours. The most wonderful Newnes Publishers have revealed within their 1938 booklets the engine acceptance tests used by Bristols for their air cooled radials. A new type design might be subject to a 100 hours test, with strip down in between. A production engine test would run for a similar duration to the Packard. I figure that we should find a protocol somewhere in between. It would be useful to find a copy of an original Cheetah factory acceptance chart.
I am also after NOS copper-lead steel backed main bearings for Cheetah, please.
I have boxes of P&W 1830 if anybody wants any.
powerandpassionSimon says sintering’s sinteresting
At the Avalon Airshow recently held in Victoria, Australia, a gaggle of brave industry reps stayed behind to expose themselves to the army of i-diots like me who descend on the trade stands on public days, looking for bowls of free lollies or misplaced VIP trade passes. In between I was able to talk to some very interesting folk about processes used in modern aerospace to address the issues tabled here for worn vintage aerospace components.
In tracking these things over the last decade I get a sense that we are very close indeed to getting these processes accepted as mainstream. It is not the processes themselves that are suspect anymore, just the applied research, to build a body of data around their application. Today, heart pacemakers are mainstream, but it took many surgeons listening to Mahler as they cut open many chests to build a statistical data set on efficacy and safety.
It was interesting to see laser sintered steel alloy components edging their way from non load bearing components to critical load bearing components. Here are some photos of a guide rail bracket for underwing projectiles, worn in use, laser sintered, then machined back to specification. It was exciting to see that this was an accepted repair, in demanding service use. There were other parts there in the process of gaining acceptance, waiting on a statistical date set to build up. We are close.
So I think we should try laser sintering too, and start building a statistical data set on vintage aviation components.
So know we have three Cheetahs : HVOF, Laser Sintered and Standard Control.
powerandpassionI guess this forum is akin to the stocks of old. As much as I am uncomfortable with the public humiliation I kind of figure this gentleman would probably think about making his way down to the colonies to bamboozle and flick star dust into the eyes of a whole new audience, and there are a lot of pink coloured countries on the old map of the world. At least good to know.
When I was a younger man one of the frustrations with standing and watching airshows was that the Spitfire pilot who climbed out afterwards invariably had rheumy limbs and face that had been dragged under the hooves in the Stampede of Life! There were no sparkling youth with clean teeth and a full head of hair, much like the black and white photos of old. There were no pert breasted young women swinging their legs over the cockpit side either, just old men with a phone to the ear, getting last minute demands from some banker to settle arrears on a property transaction, or urgent demands from a lawyer to sign something to do with a divorce. For a youngster, it all seemed so far away, before you could run the straps of a dream machine over your shoulder. I didn’t see myself in them. I felt it was an impossible dream, for to look 20 years ahead was a lifetime.
Now I know better ! Now my face has has felt the Stampede ! Now I am getting to be a rheumy, balding old man, still climbing in the foothills of my dreams. I will get there, but I will be frightfully short of telomeres on the DNA. I can see that sparkle tooth’d Wes took a shortcut. I can understand him, but I can understand how dangerous he still is. So thanks FB.
I still think the industry needs a makeover. If I ever get to fly in my dream plane I will fit a box under the seat to insert a sparkle toothed, pert breasted young lady ‘pilot’. As we come into land, I will slide into the box, and she will pop out, to wave at the crowds, and inspire youth to new dreams ! I will crawl out through a waste hatch into the service trolley, to take an urgent call from a lawyer or worried financial controller, while she glides down the wing like a fabulous butterfly to take questions from the pressing throng. It will be great for the industry! Sales will lift !
Wes would be good in a job like that, only would have to weigh him in and weigh him out when allowing hangar access.
Still I reckon Wes still thinks everyone else is a mug, the jaunty way he walks out of photos taken at the court room door.
I sense trouble ahead, and are the distant hooves of the Stampede of Life wheeling around again ?
powerandpassionI think motivations evolve over time, and this can drive surprising outcomes. I figure that most of the folks who fought in WW2 were happy to see the back of the aircraft that terrified them in a number of ways. It was folk that had never been strafed or surprised by shrapnel at 20,000 feet that brought the historics back to life, out of the wonder of it all. Could you imagine that your kids would one day pull scrap metal out of the ground and make it fly ! I think in 25 years time, when pilotless drones are ubiquitous, the idea that an actual human being sat in a cockpit will draw a new generation to the wonder of bringing such contraptions back to life. They will also have access to short run tools like 3D printing for once off parts and trick around ancient circuitry with computing devices that will be thousands of times as sophisticated as the oxidising things that are needing replacement. The biggest issue will be paying the Pollution Toll for pumping CO2 into the atmosphere, and getting past the demonstrators with the signs showing penguins choking under a dump and burn. They will all gasp when a re-enactor will light up a thing called a cigarette, then step into the cockpit and light up the afterburner.
powerandpassionLooks like they flew too high, under the bridge. ‘Serial R2162’ will refer to the rudder identification, rather than aircraft, as in ‘Rudder 2162’. However, if you found the logbook for a Mosquito aircraft and in it’s preamble it lists R2162 as the rudder fitted to it you could make a connection. Air Ministry Mosquito aircraft serials/identities, the magic that you want, are two alpha, three numeric, eg RR299. I have yet to find any evidence that an Air Ministry aircraft serial number was ever stamped onto a little plate stuck on a Mosquito. The AM serial was painted on, for sure. What was also there were lots of individual component dataplates like your rudder dataplate, for wings, fuselage, ailerons, undercarriage, nearly everything. Also lots of painted dataplates on fuel tanks, oil tanks, wing tips. Not an aircraft ID, though.
powerandpassionIndeed
It’s definitely a Mossie tail leg and wheel.
I concur with my esteemed colleague, Mosquito. Should be some 98 codes visible on the small components not covered in oxide. Coat of paint and a little air in the tyre and it will be good to go again..
powerandpassionOnly guessing but :
The HS has two parallel tubular spars that are offered to two parallel tubes/sockets within the fuselage tail structure. The fwd tubular spar is higher. This would require a very precise, tilting offer, probably by two men holding the HS (with articulating elevator articulating away) and manouvering it in. Unless HS and fuselage tubes were precisely aligned, there would be difficulty mating the pieces. It is not inconceivable that a few tries were required and one or two punctures made into the doped fabric above until a larger leather patch was fitted. The rearmost tubular spar, if misaligned, would bear on a metal stringer. You can imagine ‘feeling’ it in, missing, swearing, trying again. The man on the elevator side would be getting his fingers jammed between the elevator and HS, if gripping the HS. I can see them punching a hole in the fabric, especially if the aeroplane is being rigged in level flight position, and the job is at nose level !
Another wild guess is that the patch on the Hendon Bulldog is too short, the eyelets should attach to the stringer above.
If you are patching this you should be flying soon, you madman!
powerandpassionTo alter compression ratios, would they not just slip a spacer under the cylinder to lift it off the crankcase a bit and change the pushrods for ones slightly longer?
Thanks for your kind words, bro. I think the cylinders were screwed in or out to alter compression as an intrinsic part of the design. The pushrods have to have some mechanism to cope with expansion of the barrel, but haven’t looked into it yet to understand.
I am thinking about old fuel because I think the lead was factored in as a cooling agent during combustion. In theory, a Cheetah running on modern fuel without lead will run hotter.
The other thing I am trying to understand is what time expires an air cooled barrel – just repeated cycles of heating and cooling that introduces brittleness by changing the grain structure ? ie a cylinder or two under compression eventually drop off in flight. Need to run the XRF over all parts of the Cheetah engine to understand the metallurgy to understand the logic.
AS made it easy by stamping RR50 on the aluminium crankcase which shows they were using the best possible High Duty Aluminium in the main structure. This has lasted well in all the cores that I have seen. Some of the accessories driven off the back are not in the same condition, implying cheaper silicon aluminium castings for things like fuel pumps, that are slowly turning into bauxite. If anything will drop off in flight, it will be these.
powerandpassionGood idea ! Thanks
powerandpassionBHP Hynicro
Just another reference, from an Australian context, the manufacture of Bristol Beauforts, showing S2 as BHP Nycromax, a nickel chromium alloy.
Out of interest, S11, normally used in crankshafts, is also a NiCr alloy, Hynicro.
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