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Jungmann fatality

Written by Administrator
Tuesday, 29 June 2010
Very sadly, the pilot of the beautiful Jungmann G-JUNG died after an unexplained engine failure and subsequent collision with a telegraph line in Dorsetshire, England. His passenger was severly injured in the May 2009 accident. The complete accident report has just been published and can be reviewed by clicking here. It makes very interesting reading. It would appear that the engine and its accessories were were in quite poor condition and may have shown signs of this before the accident flight.

Switzerland report

Written by Administrator
Friday, 25 June 2010
The hotel internet connection is very slow so I will have to wait until next week to post the rest of the pictures, but here are a couple of teasers:

Lara's Birthday

Written by Administrator
Thursday, 10 June 2010
Today is step daughter Lara's 19th birthday. What better way to celebrate than this ?

Stearman comes to grief at Washingto DC National airport

Written by Administrator
Tuesday, 08 June 2010
The media are reporting that while making an IMAX film for the National Air and Space museum, a Stearman nosed over and closed the runway at Washington National airport (DCA) today. Avweb Link . The moment I saw the video, I wondered if the author of this article from "Plane and Pilot" magazine had anything to do with it. It is no joke, this letter was actually published, Click here to see page one , and here for page two .

A little more progress

Written by Administrator
Tuesday, 08 June 2010
I may have said so before, but one of the fun things about reaching the completion stage of a project is counting the "lasts." I have already weleded the last weld, wired the last wire, stiched the last rib and so on. Last week I painted the last Polyfiber product, white Polytone to form a base for the yellow Ranthane to come. It got up early when the air was still and the bugs were still sleeping so that I could use nature's paint booth. I will miss the sweet smell of PolySomething in the mornings I am in the process of masking for the swiss markings, then its off to the auto paint store where they have kindly said I can use their paint booth for the final coats. The good news is that i will not be able to do that for three more weeks. Why good news? Because we are off to Switzerlad for two weeks where we will be taking in the scenery and visiting some Bucker friends along the way. I expect to return inspired and rested, ready for the final push towards that first flight. (In my dreams at least)

Arayan Lias' Jungmann flies again

Written by Administrator
Friday, 04 June 2010
It is wonderful to see Arayan Lias' Jungmann back in the air again. D-ELEV was restored some time ago but had a number of non-Bucker components installed. Aeronca style landing gear, a Maule tailwheel etc. Now, after several months at the Barnstormer's Workshop at Peach State airport in Georgia, the Bucker has new Joe Krybis gear, and many other improvement. Congratulations Arayan! Brian Karli in the cockpit, and Arayan Lias ready for a test flight

New High Def Jungmann Movies

Written by Administrator
Tuesday, 01 June 2010
Thanks to plane classics in Poland for sending these links to some spectacular Jungmann videos: http://www.flyingtv.pl/watch,sg8h4yxas4po.html http://www.flyingtv.pl/watch,dwsqybt87ohb.html http://www.flyingtv.pl/watch,6bw0o94o4pq3.html http://www.flyingtv.pl/watch,nh53ok8jpx4j.html http://www.flyingtv.pl/watch,mq522fdmvgea.html http://www.flyingtv.pl/watch,v4wgnndtkywm.html Thank you!

New 150 HP Tigre Pistons

Written by John Hopkins
Tuesday, 01 June 2010
Guys, Just a quick heads up on progress with production of new 150 hp Tigre piston sets. I have the first production set but have not had the time to fit them yet with work and all the other rectification work. Photos attached of the complete set. They are machined from solid RR2618 (Rolls Royce aircraft spec alloy) bar which is used in almost all aircraft piston manufacture here now from Merlin to Genet. Machining from solid is far safer than casting or forging, its never going to break up in flight. They are as close a copy of the pistons made for the Spanish in 1971 by Borgo pistons which were forged as opposed to the earlier pistons made in late 40s/early 50s also by Borgo which were cast. By 1971 they had deleted the undercut under the gudgeon pin bosses which is dissapproved of in modern thinking as there is prevalence to cracks here with undercuts. The interior pocket design is as close as possible to the original as maching from solid will allow. They weigh the same as the originals.The gudgeon pins, washers, circlips and compression rings are exact copies of the original Spanish, Joe Rosenberg lent some unused examples for copying. The oil control ring is modified though the groove in the piston is the same size as the original. It is a conformal sprung ring ie without its spring it would hide in the groove and have no effect, this means the effect is variable by simply modifying the length of the spring. There is alot of experience with using sprung oil control rings in Gipsy Major engines and experience has shown that too harsh a spring can cause excessive bore wear. The prototypes have been set by the manufacturers FJ Engineering to give what they think will be optimum oil control with minimal wear but this can be adjusted depending on experience. A conformal sprung ring will apparently accommodate uneven variations in the bore most effectively which should be useful in older engines. Experience with Gipsy Majors has shown that when modern oil control rings are fitted to standard pistons, due to the reduced oil quantity reaching the compression rings there is less impact absorption by the oil film of the ring movement against the ring groove wall and therefore the grooves get worn oversize very quickly. The pistons were made originally with very wide ring grooves even for an air cooled engine so that the rings would remain highly mobile to break out the carbon formation caused by the excessive amounts of oil reaching the compression rings (and your combustion chamber). For this reason the compression ring grooves have been very slightly reduced in width in the new pistons by betweem 0.10 to 0.07 of a mm to compensate. A standard original oil ring could be fitted but the compression ring grooves would need to be opened out again. The other mod is a small waist around the piston land which is a way to try and avoid damage to the land due to lead build up in the combustion chamber. This should cause the lead deposits to be less compacted by the piston action and more able to break off. The loss of material is compensated for by a 1mm increase in the height of the crown. It would be easy to delete this from the CNC program if it does not work but its worth a try on the prototype. The whole set has been made by FJ Engineering (http://www.fj-engineering.co.uk ) who have alot of experience with all sorts of piston manufacture and the company has its origins with Wellworthy Engineering who were the manufacturers for numerous aircraft pistons including the DH Gipsy Major etc. Some of the staff date from the Wellworthy days and so have first hand experience of aircraft work. They have made pistons for several aircraft over the last few years including Gipsy, Renault, Cirrus Bombardier, Genet, Merlin and are currently making ring sets for the Centaurus engines in the Royal Navy Historic Flight Sea Furies. They make pistons for many classic and vintage car clubs and also for various military engines in armoured cars etc which have worn out their entire spares stock in the dust of Iraq and Afghanistan. Unfortunately this does mean that nothing happens quickly as they are always 'up to here' with the latest order. The Tigre pistons are machined from solid on CNC and the finished on a piston lathe to give them the beer barrel shape and round crown/oval skirt which is impossible to do any other way (piston lathes are somewhat rare in ther UK as are the lathe cams to go with it). The plans have been approved by the UK Light Aviation Association, the airworthiness authority for UK registered Jungmanns. Once I have rebuilt my engine I wiil need to do a test flying program of about 15 hours before they are fully approved by the LAA, subject to any problems and mods/demods that become necessary. There have been 2 Jungmann engine failures in Europe in the last few months due to a gudgeon pin circlip coming adrift complete with its washer. The new circlips are already therefore finding a home as the fit of the originals is often poor due to them having been used so many times. Plans are also in hand to make a modern copy of the original split duct Tigre induction manifold which we think will benefit Ellison TBI fitted aircraft alongside the existing plenum chamber mod (photo of orginal attached) Regards John Hopkins G-BWHP (S4-A-07) This e-mail address is being protected from spam bots, you need JavaScript enabled to view it

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