---------------------------------------------------------- Europa-List Digest Archive --- Total Messages Posted Thu 12/20/07: 4 ---------------------------------------------------------- Today's Message Index: ---------------------- 1. 05:13 AM - Re: Update from the Gemini 100 Folks. (Peter Zutrauen) 2. 08:38 AM - Re: Paul McAllister's website (Paul Stewart) 3. 02:06 PM - Re: Paul McAllister's website (josok) 4. 02:39 PM - Re: Paul McAllister's website (Tony Krzyzewski) ________________________________ Message 1 _____________________________________ Time: 05:13:25 AM PST US From: "Peter Zutrauen" Subject: Europa-List: Re: Update from the Gemini 100 Folks. Sounds like they are covering the bases fairly well. Cheers, Pete A239 (still a pile of parts) PS- apologies for the formatting..... it was a simple cut and past from the .pdf I received. Gemini 100 Current Status There has been some slippage in PPD' original schedule, mainly due to long lead time items such as castings, forgings and more specifically crankshafts which will not be arriving in Hastings until the first part of January. This pushes the running of the engine on the test cell out to the first week of February. Shortly afterwards we will complete some propeller analysis, installation work and flight test. Once this is accomplished we will start production and anticipate deliveries to the experimental market in July 2008. In parallel we will be working towards ASTM approval and anticipate achieving it in December 2008. We appreciate the patience that each of our customers have shown since our announcement at Air Venture in July, 2007. We have received nothing but support and congratulations from the industry. Gemini 125 Current Status We have received a tremendous amount of interest in the Turbocharged Gemini 125 with most of the questions centered on availability. We anticipate delivering the Gemini 125 to the market in December 2008. The major difference between the Gemini 125 and the Gemini 100 is of course the Turbocharger and attaching hardware. Engineering is also contemplating a piston change which of course prohibits any field conversions, which is one of the common questions we are asked. PPD will offer a special exchange price for those customers originally purchasing a Gemini 100 and then upgrading to a Gemini 125 once available. Overall dimensions of the Gemini 125 will be the same as the Gemini 100 for the width 22.68 in. and the height 15.75 in. The length will be 1.18 in. longer than the Gemini 100 coming in at 22.83 in. Pricing Status PPD has established the introductory retail price for the Gemini engines at: Gemini 100 $18,000.00 Gemini 125 $23,500.00 These are introductory prices and are subject to change. Please contact PPD for updated pricing and delivery schedules. Order Status Currently PPD' production through August has been sold out. If you would like to place an order a refundable $2500 deposit (which will be held in escrow) is required to place your engine into our production plan. PPD will notify you when the engine is ready to be built at which time you will have the choice of affirming your order and the $2500 is no longer refundable. You will be notified again when the engine is ready to ship and full payment of the balance will be required. Gemini Power Notes Volume 1, Issue 1 December, 2007 Powerplant Developments, Ltd. The Old Stables, Hoadlands, London Rd. Handcross, West Sussex RH17 6HB, UK Telephone: +44 (0) 1444 401325 Fax: +44 (0) 1444 400745 U.S. Cell: 214-404-3981 Frequently asked Questions One of the frequent questions we are asked deals with vibration being commonly associated with Diesel aircraft engines and what PPD has done differently. A vibration problem lies with the fight between the acceleration forces (acting on the pistons and rods) and the main inertia mass (the propeller) via the spring in the system (crankshaft, propshaft, gear flexure, etc). This can also have an undesirable effect on the auxiliary drives (although the auxiliaries usually have their own damping if found necessary, but they in turn can sometimes help slightly by providing a low level of damping). The method we have chosen on the Gemini engine to dampen the 3rd and 6th order vibratory forces common to a three cylinder engine, is to have pendulum dampers fitted to the crank in a similar way to those fitted in conventional aircraft piston engines. The pre-production engines we are running on in the test cell will also to be fitted with a torque limiter (clutch) for added protection and evaluation. This effectively dumps any excessive forces and is really the only way to guarantee that no twisting forces can be above the design level, the dampened energy being converted into heat that is taken away by the oil. If after final torsional analysis on the running Gemini engine we find the damper cannot be fully tuned to keep vibration to an acceptable level for the range of propellers to be used because of their various inertia values, we will fit a clutch as standard. The acceleration loads on the propeller should be well within its specified limits because the Gemini engine being a two stroke with relatively small cylinders produces quite a low peak torque from firing loads when compared to rival aircraftengines. Think of a conventional IO-360's 90 cu.in. cylinders pounding away with only two firing strokes per prop revolution compared to the Gemini's 32 cu.in. cylinders firing at 4.8 times per prop revolution. The propeller will feel like it is being driven by a turbine in comparison. This in turn leads to the problem that other Diesel aircraft engine manufacturers have had to overcome. The four-stroke, large capacity of one of these engines (76 cu.in. per cylinder) has the same firing pulses as the conventional gasoline four cylinders, however, their problems are greatly compounded by the exceptionally high rotational accelerations due to its higher compression ratio increasing the rate of deacceleration on compression and then acceleration over TDC, this is exacerbated by the longer stroke needed for a diesel, this in turn can produce severe 2nd & 4th harmonic orders. The peak torque loads acting on the crankshaft are also so much higher on these four stroke diesels. The Brake Mean Effective Pressure (BMEP) of the competitive 4-stroke diesel engines currently in the market place is between 226 and 272 psi at max power; compare this with the Gemini's 101 psi BMEP. It is also worth mentioning that while almost all aircraft and automotive engines take their camshaft and auxiliary drives from the whippy, free end of the crankshaft, the Gemini engine has its oil pump, injector pump and supercharger drives from the smoother drive end. The drives are actually taken from close to the smoothest point in the drive system - the nodal point. ________________________________ Message 2 _____________________________________ Time: 08:38:41 AM PST US From: Paul Stewart Subject: Re: Europa-List: Paul McAllister's website I would certainly add my name to the list of those who have benefited greatly from Paul's site. Regards Paul G-GIDY On 19 Dec 2007, at 18:32, Europa (Alfred Buess) wrote: > > > Hello everyone on the forum > > Some of you may have recognized that Paul McAllister's website > (http://europa363.versadev.com/) isn't accessible any more. The > hosting > service shut it down for unknown reasons. Paul will consider > looking for a > new hosting service, if there is enough interest in resurrecting > the site. > Thanks in advance, Paul! Those who know Paul's website will > certainly agree, > that it contains a wealth of useful information for us builders. I am > certainly not the only one who would be very happy to see Paul's > website > alive again. Shortly: Everyone who supports the resurrection of Paul's > website is ecouraged to let him know it, either via forum or directly > (paul.the.aviator@gmail.com). > > Alfred > > > > Alfred Buess, Switzerland > Europa XS #097, Monowheel, Foam shortwing, Rotax 912S, Airmaster > 332 CS > > ________________________________ Message 3 _____________________________________ Time: 02:06:54 PM PST US Subject: Re: Europa-List: Paul McAllister's website From: "josok" Absolutely, me too. That site was the inspiration to have something available for me too, and finally the europaowners site. Server space available for free Paul, under your own domain or whatever. Regards, Jos Okhuijsen Visit - www.EuropaOwners.org ________________________________ Message 4 _____________________________________ Time: 02:39:25 PM PST US Subject: RE: Europa-List: Paul McAllister's website From: "Tony Krzyzewski" Just to beat Paul to sending the message out (sorry Paul :) We've just registered europa.net.nz so that Paul can have a new home for his site alongside an archive copy of my log. Links for the two logs will be... Tony www.europa.net.nz/272/index.html Paul www.europa.net.nz/363/index.html You can also just go to www.europa.net.nz where I just discovered that one of my team has kindly created a simple home page with links to the two logs. The server has only just been created so I'll leave it up to Paul to let you all know when his log is available for access again. My archive copy won't be uploaded for a couple of weeks as I'm off on holiday shortly. May I take this opportunity to wish you all a very Merry Christmas. Regards Tony ------------------------------------------------------------------------------------- Other Matronics Email List Services ------------------------------------------------------------------------------------- Post A New Message europa-list@matronics.com UN/SUBSCRIBE http://www.matronics.com/subscription List FAQ http://www.matronics.com/FAQ/Europa-List.htm Web Forum Interface To Lists http://forums.matronics.com Matronics List Wiki http://wiki.matronics.com Full Archive Search Engine http://www.matronics.com/search 7-Day List Browse http://www.matronics.com/browse/europa-list Browse Digests http://www.matronics.com/digest/europa-list Browse Other Lists http://www.matronics.com/browse Live Online Chat! http://www.matronics.com/chat Archive Downloading http://www.matronics.com/archives Photo Share http://www.matronics.com/photoshare Other Email Lists http://www.matronics.com/emaillists Contributions http://www.matronics.com/contribution ------------------------------------------------------------------------------------- These Email List Services are sponsored solely by Matronics and through the generous Contributions of its members.