---------------------------------------------------------- Europa-List Digest Archive --- Total Messages Posted Wed 11/15/06: 16 ---------------------------------------------------------- Today's Message Index: ---------------------- 0. 04:52 AM - LOC (Matt Dralle) 1. 01:40 AM - Re: Oil cooler thermostat (nigel charles) 2. 03:50 AM - Re: Oil cooler thermostat (R.C.Harrison) 3. 03:59 AM - Re: Oil cooler thermostat (Jos Okhuijsen) 4. 04:33 AM - Re: More help from our American friends (Motorglider/Airplane Registration) (Jim Butcher) 5. 08:21 AM - Re: Oil cooler thermostat (Raimo Toivio) 6. 08:44 AM - Airport survival (John & Amy Eckel) 7. 09:02 AM - Re: Oil cooler thermostat (Gilles Thesee) 8. 09:58 AM - Re: Oil cooler thermostat (josok) 9. 11:08 AM - Re: Oil cooler thermostat (Sidsel & Svein Johnsen) 10. 01:01 PM - Re: Oil cooler thermostat (Raimo Toivio) 11. 01:57 PM - Re: Oil cooler thermostat (Gilles Thesee) 12. 01:57 PM - Re: Oil cooler thermostat (Raimo Toivio) 13. 03:00 PM - Re: Oil cooler thermostat (Duncan & Ami McFadyean) 14. 04:37 PM - Re: Oil cooler thermostat (R.C.Harrison) 15. 04:48 PM - Re: Oil cooler thermostat (Paul McAllister) ________________________________ Message 0 _____________________________________ Time: 04:52:45 AM PST US From: Matt Dralle Subject: Europa-List: LOC Each year at the end of the List Fund Raiser, I post a message acknowledging everyone that so generously made a Contribution to support the Lists. Its sort of my way of publicly thanking everyone that took a minute to show their appreciation for the Lists. Won't you take a moment and assure that your name is on that List of Contributors (LOC)? As a number of members have pointed out over the years, the List seems at least - if not a whole lot more - valuable as a building/flying/recreating/entertainment tool as your typical magazine subscription! Please take minute and assure that your name is on this year's LOC! Show others that you appreciate the Lists. Making a Contribution to support the Lists is fast and easy using your Credit card or Paypal on the Secure Web Site: http://www.matronics.com/contribution or by popping a personal check in the mail to: Matt Dralle / Matronics PO Box 347 Livermore CA 94551-0347 I would like to thank everyone that has so generously made a Contribution thus far in this year's List Fund Raiser! Remember that its YOUR support that keeps these Lists going and improving! Don't forget to include a little comment about how the Lists have helped you! Best regards, Matt Dralle Matronics Email List Administrator ________________________________ Message 1 _____________________________________ Time: 01:40:05 AM PST US From: "nigel charles" Subject: RE: Europa-List: Oil cooler thermostat >It is best to place a flap at the exit of the cowl/radiator duct. Placing an obstruction in the front destroys dynamic pressure. An we need to recover as much pressure as we can to persuade the air to flow across the rad core.< For what its worth I tried a cooler flap at the rear of the radiators. With it fully closed it cut off nearly all the airflow and it made little difference to the CHT and oil temperatures. When I was at Vichy this year I met one of our French owners (sorry I forgot his name). He has a very clever inlet cowl flap. It is part of the lower cowl in front of the radiators and has a hinge at the rear of it. In very hot weather it is lowered below the normal cowl allowing more cooling air in. In cold weather it is raised impeding airflow to the radiators. This is all controlled from the cockpit so that inflight adjustments can be made. From what he told me it works very well. I appreciate that normally control of cooling air is best done at the outlet but in this case it seems it is better to use the inlet. Nigel Charles ________________________________ Message 2 _____________________________________ Time: 03:50:46 AM PST US From: "R.C.Harrison" Subject: RE: Europa-List: Oil cooler thermostat Hi! Nigel/all My two pennyworth .....I also tried a cowl exit flap but not to close off. My Jabiru cooling system of course was ALL air cooled and the theory ventured by the Jab dealer and Factory was to extend it into the air stream and create a low pressure area aft of the cooling exit to suck out the hot air..... needless to say it made no improvement whatever. However what I did find was that it was important to maintain top cowl pressure high to promote the mass down flow of air past the engine, I even collected my cabin heating air(when not being used for purpose) and dumped it in the cowl top which also assisted. Since all the high pressure oil cooling air was directed under the sump cooling fins(Rotax oil and water cooling likewise) to leave it "floating" in the lower cowl restrained the downward flow of engine cooling air. You may ask why am I "rabbitting on" about damn Jabiru's ?.... so to my question:- What purpose do the Europa "Gills" serve? Has anyone flown with them blocked off to check the effects? As it happens, against most advice, I have decided to fit an intercooler on my 914 Turbo which of course has a huge discharge of warm air mostly into the top cowling and I'm not sure it's the right philosophy to let it exit out the "gills", with my Jabiru experiences I'm suggesting that to increase the down flow of air, even with water and oil cooling on the engine, it would be best maintaining the top cowl pressure. I never had any top cowl exits on my Jabiru set up ...all air was discharged out the lower cowl exit plus the lower cowl was "jacked" off the fuselage by approx 1" increasing the discharge annulus considerably. Any help with these questions would be gratefully received. I also would have liked to have the Rotax oil flow to its cooler selectable and/or meterable which I achieved on the Jabiru by a hand control valve operated from the P1 Position allowing most flying to be accomplished without the cooler being in circuit. The resultant warm air (even with no oil circulating though the cooler) was a primary source of cabin heat and with the oil cooler in full flow I could fry the passenger, I get the feeling that a number of Europa Rotax owners would dearly like such a facility ! Regards Bob Harrison G-PTAG (Still prepared to learn!) -----Original Message----- From: owner-europa-list-server@matronics.com [mailto:owner-europa-list-server@matronics.com] On Behalf Of nigel charles Sent: 15 November 2006 09:38 Subject: RE: Europa-List: Oil cooler thermostat >It is best to place a flap at the exit of the cowl/radiator duct. Placing an obstruction in the front destroys dynamic pressure. An we need to recover as much pressure as we can to persuade the air to flow across the rad core.< For what its worth I tried a cooler flap at the rear of the radiators. With it fully closed it cut off nearly all the airflow and it made little difference to the CHT and oil temperatures. When I was at Vichy this year I met one of our French owners (sorry I forgot his name). He has a very clever inlet cowl flap. It is part of the lower cowl in front of the radiators and has a hinge at the rear of it. In very hot weather it is lowered below the normal cowl allowing more cooling air in. In cold weather it is raised impeding airflow to the radiators. This is all controlled from the cockpit so that inflight adjustments can be made. From what he told me it works very well. I appreciate that normally control of cooling air is best done at the outlet but in this case it seems it is better to use the inlet. Nigel Charles ________________________________ Message 3 _____________________________________ Time: 03:59:51 AM PST US Subject: Re: Europa-List: Oil cooler thermostat From: "Jos Okhuijsen" Hi Svein, I have been quit and waiting for somebody else to show his wisdom. It does not come so i'll jump in with our solution here in Finland. It does away with the oil cooler completely and introduces an oil/water heat exchanger. That together with a water thermostat should keep the temps up. And because the waer temp raises quicker, it will heat the oil. It also adds an electrical water heater, so that the whole engine will be warm before start. The idea is from the Finnish rotax agent. The website is http://www.aerotecno.fi As far as i know this has not been flight tested, but the numbers seem to add up. In a hot summer the trouble spot could be the water radiator, because it will have to be able to absorb the heat energy of the oil too. But then again, if the original design, with the water and oil coolers in the same airstream works, there is no real difference. Or even better, because the airstream through the water radiator is not restricted by the oil cooler anymore. W'll see in half a year or so.. I've got some pictures somewhere if needed. Plans are to add a flap in the cooling duct, but as a beginner i do not want more workload in the cockpit. Later,maybe. -- Kind Regards, Jos Okhuijsen workshopcam http://www.okhuijsen.org/plane http:www.europaowners.org/kit600 mono xs, top on, gear in, tail wheel in, wings set, flapdrive in, tail closed, tailwheel in, tail top in, blue stuff filled, sanded and primed, fuel system in, doors done, windows in, sanding and filling the fuse and wings. ________________________________ Message 4 _____________________________________ Time: 04:33:46 AM PST US From: "Jim Butcher" Subject: Europa-List: Re: More help from our American friends (Motorglider/Airplane Registration) Alan, When you submit your Program Letter to the FAA, add a paragraph that says: "This aircraft is designed to be operated in two configurations as follows: Aircraft Configuration - 27 ft wing span with flaps Motorglider Configuration - 47.5 ft wing span with air brakes The pilot in command of this aircraft shall comply with the applicable sections of FAR Part 61 prior to operating the aircraft in any of the above referenced configurations." On the Form 8050-88, Affidavit Of Ownership for Amateur Built Aircraft, on the class line, insert "Aircraft/Motorglider". When the FAA issues the Airworthiness Certificate, be sure that it says "Aircraft/Motorglider". This allows you to operate in either configuration. An important point is the reference to Part 61. If flying in the motorglider configuration, you must have a glider license with self launch endorsement, but no medical is necessary to fly gliders. If flying in the aircraft configuration, you must have a ASEL pilots license and a medical is required. By registering as both, you are covering all bases. Once registered as an aircraft, it is difficult to change the class to motorglider or both. Note to all, you might want to register your Europa as both if you think you might want to add the MG wings in the future. Jim Butcher N241BW ________________________________ Message 5 _____________________________________ Time: 08:21:33 AM PST US From: "Raimo Toivio" Subject: Re: Europa-List: Oil cooler thermostat Yes - I confirm: ALL the Finnish Europas have water thermostat, water-oil exchanger and electric water heater as Jos wrote. Some months ago I listed the benefits of the electric water heater. ALL water cooled engines should also have water thermostat. That is a matter of course in cars - why not in planes with water cooled engines also? I think most water cooled aviation diesels have thermostats. Reasons are about same when using electric heater before cold starting: - reduces engine wear = money to your pocket - reduces fuel consumption = money to your pocket - increases the power of cabin heater = safety and convenience - reduces pollution = you have a place where to fly All the engines burning fuel love to operate in certain fixed temperature and also like to achieve that temperature asap. One of the main benefit of water cooling is its easy and automatic adjustable temperature control by thermostat. I have heard some Rotax-users in Sweden use same combination and are happy. So will we, Jos and me! Se on moro, Raimo ============= Raimo M W Toivio OH-XRT Europa XS Mono #417 OH-CVK C172 Skyhawk OH-BLL Beechcraft C45 w radial engines (grounded) 37500 Lempaala Finland tel + 358 3 3753 777 fax + 358 3 3753 100 gsm + 358 40 590 1450 raimo.toivio@rwm.fi www.rwm.fi ----- Original Message ----- From: "Jos Okhuijsen" Sent: Wednesday, November 15, 2006 1:59 PM Subject: Re: Europa-List: Oil cooler thermostat > > Hi Svein, > > I have been quit and waiting for somebody else to show his wisdom. It does > not come so i'll jump in with our solution > here in Finland. It does away with the oil cooler completely and > introduces an oil/water heat exchanger. That together with a water > thermostat should keep the temps up. And because the waer temp raises > quicker, it will heat the oil. It also adds an electrical water heater, so > that the whole engine will be warm before start. The idea is from the > Finnish rotax agent. The website is http://www.aerotecno.fi > > As far as i know this has not been flight tested, but the numbers seem to > add up. In a hot summer the trouble spot could be the water radiator, > because it will have to be able to absorb the heat energy of the oil too. > But then again, if the original design, with the water and oil coolers in > the same airstream works, there is no real difference. Or even better, > because the airstream through the water radiator is not restricted by the > oil cooler anymore. W'll see in half a year or so.. I've got some pictures > somewhere if needed. > > Plans are to add a flap in the cooling duct, but as a beginner i do not > want more workload in the cockpit. Later,maybe. > > -- > Kind Regards, > > Jos Okhuijsen > > workshopcam http://www.okhuijsen.org/plane > http:www.europaowners.org/kit600 > mono xs, top on, gear in, tail wheel in, wings set, flapdrive in, tail > closed, tailwheel in, tail top in, blue stuff filled, sanded and primed, > fuel system in, doors done, windows in, sanding and filling the fuse and > wings. > > > > > ________________________________ Message 6 _____________________________________ Time: 08:44:00 AM PST US From: "John & Amy Eckel" Subject: Europa-List: Airport survival I have and unusual subject for the forum. We are going to loose a local airport, N75, in New Jersey, USA and we are fighting to keep it. The airport is being sold because the owners can no longer afford the taxes and the local towns are planning to buy it for sport fields. A proposal has been made to the town to make the property a combination airport and playing fields. They have agreed to look into this option so we are hopeful. What I would like to know is if anyone has ever seen such a combination and how successfully they have operated together. Thank you, John Eckel, A230 ________________________________ Message 7 _____________________________________ Time: 09:02:43 AM PST US From: Gilles Thesee Subject: Re: Europa-List: Oil cooler thermostat Raimo, > ALL water cooled engines should also > have water thermostat. That is a matter > of course in cars The operational conditions are not the same : cars are designed to run for hours at low speed. They've got plenty of room to install wide and shallow radiator cores, with huge batteries to run powerful fans. They don't have weight or aerodynamical limitations (but should). > - why not in planes > with water cooled engines also? > Planes are creating a pretty fair breeze of their own. They have weight and reliability constraints. Designing a proper cooling ducts means recovering some of the cooling drag, instead of wasting it and adding fans, by-passes, etc. to try and maintain correct temps. Drag and weight reduction means improved fuel efficiency, take-off and climb performance, better cruise, etc... The cleaner the airplane, the greater the effect of even a small drag reduction. Our airplane has a clean and reliable engine installation, with adequate cooling whatever the conditions. We can always choose our target engine and oil temps. No obstructions, no thermostat, extra plumbing, fittings, etc... Just a good understanding of internal flow, and a well designed duct and flap. Regards, Gilles Thesee Grenoble, France http://contrails.free.fr ________________________________ Message 8 _____________________________________ Time: 09:58:55 AM PST US Subject: Re: Europa-List: Oil cooler thermostat From: "josok" Hi Gilles, Yes we know cars and airplanes are not the same. We know the thread started because there is a returning problem with over cooling in our circumstances. We also know that your airplane is not an Europa and has a perfectly designed cooling system. Europa's have not. There are several solutions, from redesigning the cowl with intake- our outlet-flaps to simple solutions like thermostats. Thermostats are automatic, install and forget, proved reliable technology. Probably lighter the any flap and it's non-automatic control mechanism. The new thing in this Finnish contribution is the oil/water heat exchanger, that saves the weight of the oil radiator and it's content. Since the temperatures here vary between +30 and -40 during a normal year here, a pretty fair breeze is not enough to keep temperatures within acceptable limits. I hope you can accept our different point of view. Kind Regards, Jos Okhuijsen Visit - www.EuropaOwners.org ________________________________ Message 9 _____________________________________ Time: 11:08:59 AM PST US From: "Sidsel & Svein Johnsen" Subject: Re: Europa-List: Oil cooler thermostat Thank you all very much for the additional input for further reflections. I am still not 100 pct certain what to do - or how to do it - but I have a 100 pct better basis on which to make a conclusion. If I were to build the airplane again, I would have studied the Finnish water/oil heat exchanger solution with great interest. The Rotax dealer in Sweden sells such heat exchangers, I note. Our friends in Finland a raised the issue of pre-heating before start in cold weather. I use the hair dryer-method, with a 1800 w dryer blowing into the special cooling duct for the 912S. On extra cold days another smaller dryer blows into the right side cowl opening for extra pre-heating of the oil tank. When my pre-flight inspection is done and I otherwise have everything planned and ready for the flight, the engine starts with just a brief application of choke. Between flights I have a 200 w heater under the cowl outlet behind the coolers and 2 x 60w light bulbs inside the cockpit, all with the hope of keeping the worst of the moist winter air out of the engine compartment and behind the panel. Best regards, Svein LN-SKJ ________________________________ Message 10 ____________________________________ Time: 01:01:02 PM PST US From: "Raimo Toivio" Subject: Re: Europa-List: Oil cooler thermostat Dear Gilles! > The operational conditions are not the same : cars are designed to run > for hours at low speed. They've got plenty of room to install wide and > shallow radiator cores, with huge batteries to run powerful fans. They > don't have weight or aerodynamical limitations (but should). I demand I am able to fly at any speed at any outside temperature as long as I like (within Europa limits of course). Like 50 knots @ -30C 5 hours. Or full power @ +40C. If it happens to make me happy. Just like I do with my cars. And all modern cars do have strictly weight and aerodynamical limits! They must be sleek for fuel efficiency and light enough to compensate all the necessary and "necessary" equipments In early days there were manual flaps and cowls also in cars. There were also magnetos, carburrettors, adjustable mixture and ignition, hand operated turning lights etc. I am happy these are not reality any more. Some people think grandfathers ideas are some kind of Value and they all must be found in flying apparatus. Thermostat is not so new idea, but water cooling is (in planes). Why should we start at the bottom again? Like invent a wheel again. Who is happy when leaning manually in Cessna? It is always a little risk and if not, it is bad also. In early days they say there was an engine man per engine in a plane. Fun? I am alone and would like fly, no playing games with flaps and being worried is it OK or not. Think: its minus 25C and I have to wait 15 minutes my turn to line up. My engine will be at ideal temp all the time but how about engine w/o thermostat? What about long lasting idle glidings - engine w thermostat will thank you and it get an serial orgasm. The size of the thermostat is like a babys fist and the weight is about 200 grams. Its price is insignificant. > No obstructions, no thermostat, extra plumbing, fittings, etc... > Just a good understanding of internal flow, and a well designed duct and > flap. That is it. The engine inside temperature should be controlable some how. Flap assembly does the job also so and so but look at the list below: - it is heavy (thermostat is light weight) - it is complicated (thermostat is simple) - it is unic hand work (thermostat is a mass serial product) - it is hard to install (thermostat is straightforward) - it tooks space and you have not it too much w Europa (thermostat does not) - it needs regular service and inspections (thermostat is forgetable) - it is expensive (thermostat is cheap) - it is manual and you have one knob more (thermostat is automatic) - it is not always in ideal position, because it is pilot operated (thermostat is always in ideal position, no steps) - when broken, it can happen in closed position and it stays closed (thermostat stays open when broken but that situation happens almost never - they are highreliable) - when starting, cold water is cooling your engine harmly instantly (when thermostat water is not cooling the engine until necessary) Hey we all should be experimental men! We can, we have to and we are allowed to experiment what ever we want (at least here in Finland). Jos and I are brave men and we have decided to test that sensational equipment: A WATER THERMOSTAT IN A WATER COOLED ENGINE. We promise to report later about thermostat but I am sure there is nothing to report exept it works well. It is so obvious. In other case I personally promise to eat it. Is nt that so, Jos? Ideal Temperature Regards, Raimo ======================= > > Regards, > Gilles Thesee > Grenoble, France > http://contrails.free.fr > > > > > > > > > > > > > ________________________________ Message 11 ____________________________________ Time: 01:57:19 PM PST US From: Gilles Thesee Subject: Re: Europa-List: Oil cooler thermostat Raimo, > - it is heavy (thermostat is light weight) > - it is complicated (thermostat is simple) > - it is unic hand work (thermostat is a mass serial product) > - it is hard to install (thermostat is straightforward) > - it tooks space and you have not it too much w Europa (thermostat does not) > - it needs regular service and inspections (thermostat is forgetable) > - it is expensive (thermostat is cheap) > - it is manual and you have one knob more (thermostat is automatic) > - it is not always in ideal position, because it is pilot operated > (thermostat is always in ideal position, no steps) > - when broken, it can happen in closed position and it stays closed > (thermostat stays open when broken but that situation happens > almost never - they are highreliable) > - when starting, cold water is cooling your engine harmly instantly > (when thermostat water is not cooling the engine until necessary) > > Everyone here is entitled to express one's technical opinion, and clearly your are sold on the water thermostat ! I understand your motivations, and wouldn't try to dissuade you. I would say that you are right on most of the above points concerning the thermostat. Like many others, I sure would appreciate any technical feedback on it's operation. I only intervened in this topic because I (maybe wrongly) got the impression that you were asking questions about cooling. I just hope I too am entitled to express my opinion on cowl flaps, based on many hours experimenting and flying them, with findings somewhat different than most of the above points. Best regards, Gilles http://contrails.free.fr ________________________________ Message 12 ____________________________________ Time: 01:57:19 PM PST US From: "Raimo Toivio" Subject: Re: Europa-List: Oil cooler thermostat ----- Original Message ----- From: "Sidsel & Svein Johnsen" Sent: Wednesday, November 15, 2006 9:07 PM Subject: Re: Europa-List: Oil cooler thermostat > > Our friends in Finland a raised the issue of pre-heating before start in > cold weather. Yes and here is some more: engine pre-heating can be automatic controlled by outside air temp thermostat. It heats in cycles. Also, one hour before flight, send a SMS via GSM or over net and you have a summer cabin in minus 30C. These are here everyboys equipments in cars and and now also in Europas. We have a saying "it starts like under the palm-tree". I considered also radio controlled fuel burning 2 kw lightweight Webasto but it proved to be too fun to be true: serious problems with exhaust gas pressures when airborne. But I know a person who is going to solve this problem. He is Finnish... If somebody like to investigate, check type 2000S: http://www.webasto.co.uk/general/en/am_recreational_vehicles_3232.html Think about this dream: you and your Europa with diesel Webasto land to huge airport. You order a fuel truck to refuel JET A1. They refuel you full, it is only one liter. After that you start your Webasto (which is w/o silencer!). Everybody can hear a real jet-sound. After couple of minutes you start your whisper-quiet Rotax and fly away. Everybody will remember JET-Europa, which was refueled full by one liter. I talked this story to Ivan Shaw in 1999 PFA Rally and he liked it. Regards, Raimo > > Best regards, > Svein > LN-SKJ > > > > > > ________________________________ Message 13 ____________________________________ Time: 03:00:41 PM PST US From: "Duncan & Ami McFadyean" Subject: Re: Europa-List: Oil cooler thermostat Probably not much, other than to create a disproportionately large amount of drag. There must be a huge plume of air coming out of these gills that destroys the airflow down the sides of the fuselage. I had a nice photo of an oil streak on Williams Europa, showing flow reversal just aft of the gills. Conversion of the gills to a rear-facing exit may prove beneficial (to reducing cooling drag), although care needed to ensure fuselage composite not overheated. I have the moulds for such a mod., but never tried it out. The detailing on Daryl Greenermeyer's Reno Legacy shows the way to go. Duncan McF ----- Original Message ----- From: R.C.Harrison To: europa-list@matronics.com Sent: Wednesday, November 15, 2006 11:43 AM Subject: RE: Europa-List: Oil cooler thermostat What purpose do the Europa "Gills" serve? ________________________________ Message 14 ____________________________________ Time: 04:37:56 PM PST US From: "R.C.Harrison" Subject: RE: Europa-List: Oil cooler thermostat Hi! Duncan. Thanks for that message. I spoke to Andy Draper today and he said that the gills initially were put in for cooling when parking up, and had been surprised when flying without doors once he put his hand over the port gills and found hot air! This rather substantiates my not having the gills as a Jabiru Cowl. The Jabiru Carb sits right above the muffler and I had a suitably placed soldering mat on top of the muffler , can't see why this shouldn't work for Rotax and leave the gills blocked Regards Bob Harrison. Robt.C.Harrison -----Original Message----- From: owner-europa-list-server@matronics.com [mailto:owner-europa-list-server@matronics.com] On Behalf Of Duncan & Ami McFadyean Sent: 15 November 2006 22:56 Subject: Re: Europa-List: Oil cooler thermostat Probably not much, other than to create a disproportionately large amount of drag. There must be a huge plume of air coming out of these gills that destroys the airflow down the sides of the fuselage. I had a nice photo of an oil streak on Williams Europa, showing flow reversal just aft of the gills. Conversion of the gills to a rear-facing exit may prove beneficial (to reducing cooling drag), although care needed to ensure fuselage composite not overheated. I have the moulds for such a mod., but never tried it out. The detailing on Daryl Greenermeyer's Reno Legacy shows the way to go. Duncan McF ----- Original Message ----- From: R.C.Harrison Sent: Wednesday, November 15, 2006 11:43 AM Subject: RE: Europa-List: Oil cooler thermostat What purpose do the Europa "Gills" serve? ________________________________ Message 15 ____________________________________ Time: 04:48:24 PM PST US From: "Paul McAllister" Subject: Re: Europa-List: Oil cooler thermostat Hi All, Actually I have my gills rear ward facing. It wasn't by design, I just made a mistake and I didn't even know until Andy pointed it out to me. Although I don't have before and after measurements, the underneath of my cowl seems cooler that some other people have reported. I base this on the fact that I don't have any cable ties that melt under the cowl, whereas I have heard many reports from others. One of these days I must smear a bit of oil around to see what is happening Paul -----Original Message----- From: owner-europa-list-server@matronics.com [mailto:owner-europa-list-server@matronics.com]On Behalf Of Duncan & Ami McFadyean IConversion of the gills to a rear-facing exit may prove beneficial (to reducing cooling drag), although care needed to ensure fuselage composite not overheated. I have the moulds for such a mod., but never tried it out. Duncan McF