---------------------------------------------------------- Europa-List Digest Archive --- Total Messages Posted Sat 10/11/08: 14 ---------------------------------------------------------- Today's Message Index: ---------------------- 1. 02:32 AM - Re: Popham Sunday? (G-IANI) 2. 05:01 AM - Re: O2 needs at altitude (Karl Heindl) 3. 05:41 AM - Boiling fuel due to underpressure? (Frans Veldman) 4. 05:43 AM - Re: O2 systems (TELEDYNMCS@aol.com) 5. 06:40 AM - Re: Boiling fuel due to underpressure? (Gilles Thesee) 6. 07:18 AM - Re: Boiling fuel due to underpressure? (Frans Veldman) 7. 07:45 AM - Re: Re: Boiling fuel due to underpressure? (Gilles Thesee) 8. 07:59 AM - Re: O2 needs at altitude (Paul McAllister) 9. 08:07 AM - Re: Re: Boiling fuel due to underpressure? (G-IANI) 10. 10:56 AM - Re: Re: Boiling fuel due to underpressure? (pjeffers@talktalk.net) 11. 11:14 AM - Re: Re: Boiling fuel due to underpressure? (Frans Veldman) 12. 12:44 PM - =?ISO-8859-1?Q?Re=3A_Europa-List=3A_Popham_Sunday=3F? (Carl Pattinson) 13. 02:07 PM - Adhesive Question (Paul McAllister) 14. 04:25 PM - Re: O2 needs at altitude (craig bastin) ________________________________ Message 1 _____________________________________ Time: 02:32:55 AM PST US From: "G-IANI" Subject: RE: Europa-List: Popham Sunday? Yes to Popham, weather permitting. Ian Rickard G-IANI XS Trigear ________________________________ Message 2 _____________________________________ Time: 05:01:34 AM PST US From: Karl Heindl Subject: RE: Europa-List: O2 needs at altitude Craig=2C I use an Aerox cylinder=2C 9 cft=2C which is supposed to last up to 16 hour s. It fits neatly inside the port 'headrest'. Karl
From: craigb@onthenet.com.auTo: europa-list@matronics.comSubject: Europa-Li st: O2 needs at altitudeDate: Sat=2C 11 Oct 2008 15:58:07 +1000 For those of you with completed AC or previous experience=2C I would like y o know what you use for supplimental O2 needs at say 15=2C000 ft. specifcally size of bottles=2C lo cation=2C weight and how long they last in flight. Some of the legs here in australia=2C like north america=2C or UK across europe=2C could be 6+ hours duration and i want to make sure i have enough capacity. I realise this will vary depending on age=2C h ealth=2C fitness level etc. Secondly has anyone used or considered the clip on O2 sensors (ear lobe/little finge r) to monitor blood O2 levels accurately. Craig ________________________________ Message 3 _____________________________________ Time: 05:41:23 AM PST US Subject: Europa-List: Boiling fuel due to underpressure? From: "Frans Veldman" I guess somebody here can tell me whether this is normal or not. While testing my just finished fuel system on my 914, I noticed that quite some air was passing through the filters. (I temporarily use the factory supplied "glass" filters, to see what is going on and how much gunk will be collected during the fuel flow tests). I of course expected some air in the system, and also expected it to last some time before the last bubble would be gone. Today I decided to let the fuel pump run while I was doing some other things, just to see if there were no small leaks and to "flush" the fuel system. After some time I noticed that the "air" still wasn't gone, actually it got worse. It looks like massive amounts of air are sucked in, also regulary I hear the pumps swallowing some air. Although I have no fuel leaks if I leave the system alone, I suspected to have an air leak upstream the suction side of the filters. Air can pass through smaller holes than fuel I think. It doesn't matter whether I'm on Main or Reserve, so it had to be after the fuel selection valve and before the filters. Happy with that, because that is just one hose, and a Tee to both filters. Now I'm not too happy anymore, because after spending a few hours chasing this mystery air leak, I'm quite convinced there is no leak. Of course there could be air leaks in both connections before the fuel selection valve, but this would be a dual fault, and not too likely. If I close the fuel selection valve while the pumps are still running, the fuel in the filters is instantly gone. In fact, this is how I empty the filters before disconnecting them. After test #687 and disconnecting once again one of the filters, a few minutes after I got the filters sucked empty, I noticed how the air got sucked in again when I pulled the hose of it. It indicates that the vacuum is pretty good preserved during these few minutes, and this is in contradiction with the assumption that I have an air leak. At the same time, the amount of air I see through the fllters is increasing all the time, it looks at the moment like the air/fuel ratio is 50%. Still though, the pumps humm happy and don't seem to ingest much of this "air". Something is not right here. As indicated by two fuel flow sensors, there is 130 liters per hour of flow, and the fuel pressure is about 5 psi over the airbox pressure. (The engine is not running, can't do that yet because I'm not finished with the rest of the installation). Before I go crazy completely, let me ask a question. Is it possible, that while the pumps are pumping 130 liters per hour through the system, that the underpressure on the suction side of the pumps just lowers the boiling point of the fuel so much that the fuel starts "boiling"? Maybe it is just normal to see all these bubbles dancing around in the fuel filters? If anyone has noticed this as well, please let me know, it saves me a lot of time chasing "ghost" air leaks. Temperature at the moment is a nice 20 Celcius and the airplane has been standing in the sun for a while. (Yup, I know that sun isn't good for composite airplanes, but messing with the fuel in a confined space isn't very good for me). It would explain why today it is much worse than yesterday evening: the temperature is much higher today, It also explains why the amount of "air" apparently sucked in is much more than the occasional burp I hear through the fuel pumps. If this is not normal, I can only suspect to have air leaks on both tank connections. Tiny enough not to let them drip overnight, but big enough to let massive amounts of air in while the pumps start running... Frans Visit - www.EuropaOwners.org ________________________________ Message 4 _____________________________________ Time: 05:43:42 AM PST US From: TELEDYNMCS@aol.com Subject: Europa-List: Re: O2 systems In a message dated 10/11/2008 3:01:08 A.M. Eastern Daylight Time, europa-list@matronics.com writes: For those of you with completed AC or previous experience, I would like yo know what you use for supplimental O2 needs at say 15,000 ft. specifcally size of bottles, location, weight and how long they last in flight. Hey Craig, With the exception of the occasional wave day, we don't have much use for O2 here in the SE USA but a lot of our glider customers who fly in the mountains out west like the Mountain High O2 systems. This is probably the most common O2 system we see in gliders that come through our shop. The MH system uses a pulsed, on-demand regulator and that, I'm told, saves a lot of O2. Fairly important when you are flying out on the middle of nowhere when refills are scarce. These folks also sell the finger type pulse oximeters that monitor your O2 saturation. Here's a link: _www.mhoxygen.com_ (http://www.mhoxygen.com) Hope it helps! Regards, John Lawton Whitwell, TN (TN89) N245E - Back flying now that UL93 fuel is finally available again..... **************New MapQuest Local shows what's happening at your destination. Dining, Movies, Events, News & more. Try it out (http://local.mapquest.com/?ncid=emlcntnew00000002) ________________________________ Message 5 _____________________________________ Time: 06:40:40 AM PST US From: Gilles Thesee Subject: Re: Europa-List: Boiling fuel due to underpressure? Frans Veldman a crit : > Before I go crazy completely, let me ask a question. Is it possible, that while the pumps are pumping 130 liters per hour through the system, that the underpressure on the suction side of the pumps just lowers the boiling point of the fuel so much that the fuel starts "boiling"? Maybe it is just normal to see all these bubbles dancing around in the fuel filters? If anyone has noticed this as well, please let me know, it saves me a lot of time chasing "ghost" air leaks. Temperature at the moment is a nice 20 Celcius and the airplane has been standing in the sun for a while. (Yup, I know that sun isn't good for composite airplanes, but messing with the fuel in a confined space isn't very good for me). Frans, You're spot on. And not crazy at all, by the way ;-) We also noticed those bubbles in the transparent test lines when testing our fuel system. This is normal behaviour for fuel when "sucked" by pumps that are *above* fuel level. Aviation fuels, and to a greater extent autogas are a mix of many hydrocarbon substances, several of which have a very low boiling point. Autogas can even contain some butane and propane solved. So when sucked out by the pumps, the most volatile hydrocarbons turn to vapour. We have flown our airplane up to FL 135/145 with no problem, but I must admit that a fuel system with pumps below fuel level would be far better. FWIW, Best regards, -- Gilles http://contrails.free.fr ________________________________ Message 6 _____________________________________ Time: 07:18:56 AM PST US Subject: Europa-List: Re: Boiling fuel due to underpressure? From: "Frans Veldman" Ok, once I started to suspect that I didn't have an air leak but just boiling fuel, I decided to do a simple test (should have thought about that earlier): I connected one of these glass filters to the fuel inlet of the engine, so I could see what the engine was getting. While the inlet filter looked like I was pumping foam, the filter at the inlet of the engine showed that the engine was only getting liquid fuel, without a single bubble of air... Now I have determined that I have no air leak but simply that my fuel is boiling due to underpressure at the suction side of the fuel system, I have some further questions: 1) Is this nornal, or do I have bad fuel, or for some reason too much underpressure that is causing this? With other words, do I have a problem? 2) At altitude, the pressure will be even lower, hence the fuel will boil earlier. Today is a nice fall day, but the temperatures are nowhere as high as I'm going to experience during my flights in the south of Europe. Isn't it likely that some of the vapour bubbles will make it into the carbs once the conditions go "worse"? Once you have vapour, the bubbles tend to grow rather than to dissolve. It just doesn't look good that the fuel is already boiling at this comfortable but not too high a temperature at 10 ft AMSL... Frans Visit - www.EuropaOwners.org ________________________________ Message 7 _____________________________________ Time: 07:45:50 AM PST US From: Gilles Thesee Subject: Re: Europa-List: Re: Boiling fuel due to underpressure? Franz > Ok, once I started to suspect that I didn't have an air leak but just boiling fuel, I decided to do a simple test (should have thought about that earlier): I connected one of these glass filters to the fuel inlet of the engine, so I could see what the engine was getting. > > While the inlet filter looked like I was pumping foam, the filter at the inlet of the engine showed that the engine was only getting liquid fuel, without a single bubble of air... > Congratulations for this example of practical engineering sense. All 914 owners will benefit from such experiments. > Now I have determined that I have no air leak but simply that my fuel is boiling due to underpressure at the suction side of the fuel system, I have some further questions: > > 1) Is this nornal, or do I have bad fuel, or for some reason too much underpressure that is causing this? With other words, do I have a problem? > 2) At altitude, the pressure will be even lower, hence the fuel will boil earlier. Today is a nice fall day, but the temperatures are nowhere as high as I'm going to experience during my flights in the south of Europe. Isn't it likely that some of the vapour bubbles will make it into the carbs once the conditions go "worse"? Once you have vapour, the bubbles tend to grow rather than to dissolve. It just doesn't look good that the fuel is already boiling at this comfortable but not too high a temperature at 10 ft AMSL... > > We regularly fly over the French Alps at FL 130+ with no problem. I imagine you won't have to climb that high to clear terrain every day in the Netherlands ;-) The point is, the fuel pressure at the carbs is higher than airbox pressure, so the fuel won't be boiling and any vapour bubble will be collapsed by positive pressure. *But* there is always the risk that the pumps be starved should the "boiling" become too intense at the tank pickup. As already said, the only real cure is to *push* fuel and not *draw* it up to the pumps. But this often implies a major redesign of the fuel tank and fuel system. Best regards, -- Gilles http://contrails.free.fr ________________________________ Message 8 _____________________________________ Time: 07:59:21 AM PST US From: "Paul McAllister" Subject: Re: Europa-List: O2 needs at altitude Hi Craig, I have a Mountain High pulse on demand system with a 22 cubic foot Kevlar cylinder mounted on the back of the "D" bulk head. The pulse demand unit sits between the two pilots and I am using the pneumatic on off switch / valve that Mountain High supply. This is mounted in the over head panel. It did require me running tubing around the place and threading through my already full cable ducts was a bit of a pain, but it is all out of sight and looks fairly neat. So far I am delighted with the system. Most of my flying is two cross country legs of 3 to 3.5 hours. Winds permitting I typically fly in the 14,000 to 16,000 feet range. The cylinder seems to last a very long time. To be honest apart from my initial fill, I haven't bought oxygen since, I get it filled at airshows twice a year and Jim Butcher gave me a fill once, so running out on a cross country trip is just not a concern. >From a physiological perspective I always use it from 10,000 feet and above, and if I know I am climbing to that altitude I use it from the commencement of the flight. The Mountain High unit can be set to turn itself on automatically from 5000 feet. I am a non smoker, over 50 and I workout several times a week so I am in pretty good shape, but with that said I find that using oxygen significantly improves my well being and general cognitive performance. I can't imagine how a sedentary smoker of my age or older would be performing at altitude. So, in conclusion, I really like the Mountain High Pulse demand system, 22 cubic feet will last you a very long time, and lastly, from what I know now, if your poking around at 10,000 feet or more, you probably should be using oxygen. What don't I like about the system ?. It cost a lot ! Paul ________________________________ Message 9 _____________________________________ Time: 08:07:39 AM PST US From: "G-IANI" Subject: RE: Europa-List: Re: Boiling fuel due to underpressure? Frans The pumps behave as Gilles described. I have seen bubbles in the pumps at any temperature from 0C to 35C on a hot day and with various fuels. From experience this is nothing to worry about. The engine gets only what it needs from the pumps and continues to run very sweetly. Ian Rickard G-IANI XS Trigear, 200 hours Europa Club Mods Rep (Trigear) e-mail mods@europaclub.org.uk or direct g-iani@ntlworld.com ________________________________ Message 10 ____________________________________ Time: 10:56:25 AM PST US Subject: Re: Europa-List: Re: Boiling fuel due to underpressure? From: pjeffers@talktalk.net Hi guys, I now have 1250 hours and since new there have always been lots of bubbles in the filters.when the pump is running.? All i can do is reassure anyone that this is completely normal.? Don't know why but is OK. Pete Jeffers -----Original Message----- From: G-IANI Sent: Sat, 11 Oct 2008 16:06 Subject: RE: Europa-List: Re: Boiling fuel due to underpressure? Frans The pumps behave as Gilles described. I have seen bubbles in the pumps at any temperature from 0C to 35C on a hot day and with various fuels. From experience this is nothing to worry about. The engine gets only what it needs from the pumps and continues to run very sweetly. Ian Rickard G-IANI XS Trigear, 200 hours Europa Club Mods Rep (Trigear) e-mail mods@europaclub.org.uk or direct g-iani@ntlworld.com ________________________________ Message 11 ____________________________________ Time: 11:14:36 AM PST US From: Frans Veldman Subject: Re: Europa-List: Re: Boiling fuel due to underpressure? Gilles Thesee wrote: > We regularly fly over the French Alps at FL 130+ with no problem. > I imagine you won't have to climb that high to clear terrain every day > in the Netherlands ;-) We won't stay with the Europa in the Netherlands. Quite a substantial amount of flying will be done in the French Alps, as my wifes parents live close to Barcelonnette, and we love to fly over there (she has a PPL also). We have been there twice this year, with a Cessna with Thielert conversion. The bad news with a Cessna is its poor climb rate, but the good news with this Cessna is that it is turbo-charged, and it always climbs with 500 ft per minute, on sea level, but also on 12.500 feet. It is one of the reasons we wanted to have a 914 (turbo) in the Europa as well. We are looking forward to start flying over there with our Europa once it is finished. These plans are one of the reasons I want to make sure the fuel system is working correctly, also at altitude, in the mountains where you won't find acceptable emergency landing spots everywhere. Frans ________________________________ Message 12 ____________________________________ Time: 12:44:20 PM PST US From: "Carl Pattinson" Subject: Europa-List: =?ISO-8859-1?Q?Re=3A_Europa-List=3A_Popham_Sunday=3F? X-mailer: iAVMailScanner 1.5.5.5 We are planning to be there for lunch 12 - 1 ish hopefully.. Carl & Dot G-LABS ----- Original Message ----- From: Richard Iddon To: europa-list@matronics.com Sent: Friday, October 10, 2008 4:30 PM Subject: Europa-List: Popham Sunday? Anyone heading for Popham this Sunday for their end of season fly-in? Richard Iddon G-RIXS ========= ========= ========= ========= ------------------------------------------------------------------------------ No viruses found in this incoming message Scanned by iolo AntiVirus 1.5.5.5 http://www.iolo.com _______________________________________ No viruses found in this outgoing message Scanned by iolo AntiVirus 1.5.5.5 http://www.iolo.com ________________________________ Message 13 ____________________________________ Time: 02:07:54 PM PST US From: "Paul McAllister" Subject: Europa-List: Adhesive Question Hi All, I have an engine heater which is made up of a band that heats the oil tank and a stick on pad on the engine block. I noticed today that the the heating pad on the engine block came unstuck. When I installed it, it came with some adhesive that looked like gray silicon. Does anyone happen to know what type of adhesive is used for this ? Thanks, Paul ________________________________ Message 14 ____________________________________ Time: 04:25:25 PM PST US From: "craig bastin" Subject: RE: Europa-List: O2 needs at altitude Thanks for all the replies on and off list, the MH systems look quite good, with the on demand pulse system unless the law has been changed I am required to carry O2 at 10000 ft and required to use it at 12000ft. The auto on system at 5000ft is a nice feature too thanks craig ------------------------------------------------------------------------------------- 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.