---------------------------------------------------------- RV10-List Digest Archive --- Total Messages Posted Fri 10/15/10: 20 ---------------------------------------------------------- Today's Message Index: ---------------------- 1. 04:27 AM - Re: Painting screws and small parts - what to stick them in - foam? (Bill Watson) 2. 04:35 AM - Re: fuel valve with position both (Werner Schneider) 3. 04:47 AM - Re: fuel valve with position both (Linn Walters) 4. 05:37 AM - Re: Painting screws and small parts - what to stick them in - foam? (Lew Gallagher) 5. 05:40 AM - Re: fuel valve with position both (Werner Schneider) 6. 05:54 AM - Re: California Trip - Catalina Island (darnpilot@aol.com) 7. 06:29 AM - Re: fuel valve with position both (kevino) 8. 07:15 AM - Re: fuel valve with position both (Dave Saylor) 9. 07:41 AM - Re: Painting screws and small parts - what to stick them in - foam? (Pascal) 10. 08:46 AM - Re: Re: California Trip - Catalina Island (Tim Olson) 11. 08:50 AM - Re: fuel valve with position both (Tim Olson) 12. 09:34 AM - Re: fuel valve with position both (Stein Bruch) 13. 10:38 AM - Re: fuel valve with position both (kevino) 14. 11:07 AM - Re: fuel valve with position both (John Melchert) 15. 11:25 AM - Re: fuel valve with position both (Robin Marks) 16. 01:17 PM - Re: fuel valve with position both (Dave Saylor) 17. 01:39 PM - Re: fuel valve with position both (Chris Colohan) 18. 02:02 PM - Re: fuel valve with position both (Werner Schneider) 19. 02:26 PM - Re: fuel valve with position both (Linn Walters) 20. 08:49 PM - Totally Off Topic - quadrotor (Ron McGann) ________________________________ Message 1 _____________________________________ Time: 04:27:54 AM PST US From: Bill Watson Subject: Re: RV10-List: Painting screws and small parts - what to stick them in - foam? Thanks all. So many solutions, so dull a mind. I'm sure I have a few ACS boxes lying around. Bill On 10/14/2010 7:33 PM, Dave Saylor wrote: > --> RV10-List message posted by: Dave Saylor > > Poke some holes into a cardboard box with an awl and press the screws > into the holes. Aircraft Spruce boxes seem to work particularly well... > > Dave Saylor > ________________________________ Message 2 _____________________________________ Time: 04:35:46 AM PST US From: Werner Schneider Subject: Re: RV10-List: fuel valve with position both Thanks Linn, I agree, on a high wing the fuel pressure is higher, but on a low wing you still pressurize the tanks as well so you should be fine? Unporting would only be possible on a very low fuel level or uncoordinated flight I plan to add low fuel warnings as well (have them in my Star as we have a SB concerning the same problem). Will see if we get deeper into that "why". Cheers Werner Glastar HB-YKP flying RV-10 #41122 waiting for shipping On 14.10.2010 22:45, Linn Walters wrote: > > No flames. Actually, it's a good question. > On the high wing, the valve is always under positive fuel pressure (in > any attitude but inverted .... ;-) ) due to the head .... 5' maybe? > On the low wing, it would be possible to unport one tank feed ..... and > suck air. > Linn > > On 10/14/2010 4:32 PM, Werner Schneider wrote: >> >> I might open Pandoras box here but it's not about primer so lets try: >> >> On my high wing Glastar I have a left/both/right fuel valve and it is >> used most of the time in the both mode, except when on the ground >> (crossfeed risk) or on low fuel situations. >> >> Now on low wing airplanes I see the left/right only, what is the >> reason for it (I guess there must be a technical reason behind that)? >> >> ok I get my firesuite out before I get the flames >> >> Werner >> >> >> >> >> >> > > ________________________________ Message 3 _____________________________________ Time: 04:47:32 AM PST US From: Linn Walters Subject: Re: RV10-List: fuel valve with position both On 10/15/2010 7:31 AM, Werner Schneider wrote: > > Thanks Linn, > > I agree, on a high wing the fuel pressure is higher, but on a low wing > you still pressurize the tanks as well so you should be fine? > Unporting would only be possible on a very low fuel level or > uncoordinated flight > I plan to add low fuel warnings as well (have them in my Star as we > have a SB concerning the same problem). > > Will see if we get deeper into that "why". Well, you already did!! I'm not sure how much 'usable fuel' you will get ...... the valve is mounted at the top of the tunnel ..... run that station out to the wing tank and see how much fuel you leave in the tank. Better to just take a pass on the 'both' valve. Linn > > Cheers Werner > > Glastar HB-YKP flying > RV-10 #41122 waiting for shipping > > > On 14.10.2010 22:45, Linn Walters wrote: >> >> >> No flames. Actually, it's a good question. >> On the high wing, the valve is always under positive fuel pressure (in >> any attitude but inverted .... ;-) ) due to the head .... 5' maybe? >> On the low wing, it would be possible to unport one tank feed ..... and >> suck air. >> Linn >> >> On 10/14/2010 4:32 PM, Werner Schneider wrote: >>> >>> I might open Pandoras box here but it's not about primer so lets try: >>> >>> On my high wing Glastar I have a left/both/right fuel valve and it is >>> used most of the time in the both mode, except when on the ground >>> (crossfeed risk) or on low fuel situations. >>> >>> Now on low wing airplanes I see the left/right only, what is the >>> reason for it (I guess there must be a technical reason behind that)? >>> >>> ok I get my firesuite out before I get the flames >>> >>> Werner >>> >>> >>> >>> >>> >>> >> >> >> >> >> >> >> > > ________________________________ Message 4 _____________________________________ Time: 05:37:14 AM PST US From: "Lew Gallagher" Subject: Re: RV10-List: Painting screws and small parts - what to stick them in - foam? Hey Bill, I fooled around with spraying a bunch of screw heads, but here's what I ended up doing. Spraying the heads tends to fill up the slot and painting the heads after installed with a small paint brush really doesn't take that much time, doesn't fill the slot, doesn't "weld" the screw to the body, doesn't use much paint, have overspray, etc. The countersunk parts that receive the screws that got painted without screws in them, caused tears in the paint when screws were tightened in them, so I quickly learned to drill out the paint before seating screws in them. One of my wife's make up "paint" brushes works great -- Later, - Lew "No, Honey, I haven't seen it" Gallagher ----- Original Message ----- From: "Bill Watson" Sent: Friday, October 15, 2010 7:23 AM Subject: Re: RV10-List: Painting screws and small parts - what to stick them in - foam? > > Thanks all. So many solutions, so dull a mind. I'm sure I have a few > ACS boxes lying around. > > Bill ________________________________ Message 5 _____________________________________ Time: 05:40:14 AM PST US From: Werner Schneider Subject: Re: RV10-List: fuel valve with position both Hello Linn, no, my valve will be on the bottom of the tunnel (Andair Valve with extension) and I have still the head pressure of the tank vents. As I have still time until I'm there I will do a bit of geometry to see where I end. Thanks Werner Glastar HB-YKP flying RV-10 #41122 waiting for shipping On 15.10.2010 13:44, Linn Walters wrote: > > On 10/15/2010 7:31 AM, Werner Schneider wrote: >> >> Thanks Linn, >> >> I agree, on a high wing the fuel pressure is higher, but on a low wing >> you still pressurize the tanks as well so you should be fine? >> Unporting would only be possible on a very low fuel level or >> uncoordinated flight >> I plan to add low fuel warnings as well (have them in my Star as we >> have a SB concerning the same problem). >> >> Will see if we get deeper into that "why". > Well, you already did!! > I'm not sure how much 'usable fuel' you will get ...... the valve is > mounted at the top of the tunnel ..... run that station out to the wing > tank and see how much fuel you leave in the tank. Better to just take a > pass on the 'both' valve. > Linn > >> >> Cheers Werner >> >> Glastar HB-YKP flying >> RV-10 #41122 waiting for shipping >> >> >> On 14.10.2010 22:45, Linn Walters wrote: >>> >>> >>> No flames. Actually, it's a good question. >>> On the high wing, the valve is always under positive fuel pressure (in >>> any attitude but inverted .... ;-) ) due to the head .... 5' maybe? >>> On the low wing, it would be possible to unport one tank feed ..... and >>> suck air. >>> Linn >>> >>> On 10/14/2010 4:32 PM, Werner Schneider wrote: >>>> >>>> I might open Pandoras box here but it's not about primer so lets try: >>>> >>>> On my high wing Glastar I have a left/both/right fuel valve and it is >>>> used most of the time in the both mode, except when on the ground >>>> (crossfeed risk) or on low fuel situations. >>>> >>>> Now on low wing airplanes I see the left/right only, what is the >>>> reason for it (I guess there must be a technical reason behind that)? >>>> >>>> ok I get my firesuite out before I get the flames >>>> >>>> Werner >>>> >>>> >>>> >>>> >>>> >>>> >>> >>> >>> >>> >>> >>> >>> >> >> >> >> >> > > ________________________________ Message 6 _____________________________________ Time: 05:54:06 AM PST US Subject: RV10-List: Re: California Trip - Catalina Island From: darnpilot@aol.com (source AOPA) Catalina Island Conservancy officials know a good thing when they see it, and have extended a previous two-day offer to waive the $20 Catalina Isla nd landing fee for AOPA members during AOPA Aviation Summit. Now, the fee is waived for four days, Nov. 11 through 14, to cover the entire Summit. Response to the original offer was strong, so Conservancy officials decide d to extend the offer. Just show your AOPA membership card once you land on the island, and the fee is waived. Not only that, but you get 20 perce nt off the Wildlands Express shuttle service, normally a $17 charge. Should you happen to buy $10 worth of food at the airport=99s DC-3 Gifts and Grill shop, you=99ll get a free Killer Cookie, so the goo d news just keeps rolling in. For those making the trip to Catalina more frequently, such as California pilots, there is an additional option. Join the new Catalina Aero Club fo r $150 per year, and you=99ll have unlimited free landing privileges . =9CI am thrilled to see the pilots who make Catalina one of their mo st popular destinations want to redefine their commitment to the protectio n and recreation of the Island through their membership in the new Catalin a Aero Club,=9D said Conservancy President Ann Muscat. Other benefits to club members include one annual Freewheeler bike pass an d 50 percent off Conservancy campground fees. Current Conservancy members who would like to upgrade to the Aero Club can do so and extend their membership for $115. Those who are current Leaders hip Circle members can now enjoy unlimited free landings at Airport in the Sky.=94Alton K. Marsh Jeff Darnall Jacksonville, FL 904-234-8718 __i__ *-----o--o--(_)--o--o-----* ________________________________ Message 7 _____________________________________ Time: 06:29:12 AM PST US Subject: RV10-List: Re: fuel valve with position both From: "kevino" I have some experience on this topic. During phase 1 testing on my 10 i ran a tank dry over airport and had an engine failure. Was unable to get other tank on line due to air in system. Dead stick landing. no issues. discovered that the vans fuel valve which was left, right and aux was allowing the good tank to still draw air due to being slighty out of the detent position. lousy detent on vans valves. replaced valve with andair. no further issues. not a fan of cheap valves on low wing airplanes. you cannot use a valve with both on low wing. Kevin Read this topic online here: http://forums.matronics.com/viewtopic.php?p=315817#315817 ________________________________ Message 8 _____________________________________ Time: 07:15:20 AM PST US From: Dave Saylor Subject: Re: RV10-List: fuel valve with position both Werner, The head pressure from your Glastar tanks is many times the pressure from the fuel vent. If it weren't, high-wings on "Both" would be running out of gas all the time. Head pressure tries to push fuel back into the empty tank, against vent pressure. That works in a high-wing because you have a couple feet of rise. In a low-wing airplane there isn't enough pressure difference between an empty tank and a partially-full tank to favor the fuller tank. The pump pulls from the path of least resistance, which is the air in the empty tank. Lots of people have tried a "Both"position in RVs and other low wings. It doesn't work out. You'll build a safer plane if you stick with Left-Right-Off. I didn't have much low-wing time before my 10 and while it is something else to do, switching back and forth isn't that big a deal. Plus it really keeps you cognizant of your fuel situation. Dave Saylor AirCrafters 140 Aviation Way Watsonville, CA 95076 831-722-9141 Shop 831-750-0284 Cell On Fri, Oct 15, 2010 at 5:36 AM, Werner Schneider wrote: > > Hello Linn, > > no, my valve will be on the bottom of the tunnel (Andair Valve with > extension) and I have still the head pressure of the tank vents. > > As I have still time until I'm there I will do a bit of geometry to see > where I end. > > Thanks > > Werner > > Glastar HB-YKP flying > RV-10 #41122 waiting for shipping > > On 15.10.2010 13:44, Linn Walters wrote: >> >> >> On 10/15/2010 7:31 AM, Werner Schneider wrote: >>> >>> >>> Thanks Linn, >>> >>> I agree, on a high wing the fuel pressure is higher, but on a low wing >>> you still pressurize the tanks as well so you should be fine? >>> Unporting would only be possible on a very low fuel level or >>> uncoordinated flight >>> I plan to add low fuel warnings as well (have them in my Star as we >>> have a SB concerning the same problem). >>> >>> Will see if we get deeper into that "why". >> >> Well, you already did!! >> I'm not sure how much 'usable fuel' you will get ...... the valve is >> mounted at the top of the tunnel ..... run that station out to the wing >> tank and see how much fuel you leave in the tank. Better to just take a >> pass on the 'both' valve. >> Linn >> >>> >>> Cheers Werner >>> >>> Glastar HB-YKP flying >>> RV-10 #41122 waiting for shipping >>> >>> >>> On 14.10.2010 22:45, Linn Walters wrote: >>>> >>>> >>>> >>>> No flames. Actually, it's a good question. >>>> On the high wing, the valve is always under positive fuel pressure (in >>>> any attitude but inverted .... ;-) ) due to the head .... 5' maybe? >>>> On the low wing, it would be possible to unport one tank feed ..... and >>>> suck air. >>>> Linn >>>> >>>> On 10/14/2010 4:32 PM, Werner Schneider wrote: >>>>> >>>>> >>>>> I might open Pandoras box here but it's not about primer so lets try: >>>>> >>>>> On my high wing Glastar I have a left/both/right fuel valve and it is >>>>> used most of the time in the both mode, except when on the ground >>>>> (crossfeed risk) or on low fuel situations. >>>>> >>>>> Now on low wing airplanes I see the left/right only, what is the >>>>> reason for it (I guess there must be a technical reason behind that)? >>>>> >>>>> ok I get my firesuite out before I get the flames >>>>> >>>>> Werner >>>>> >>>>> >>>>> >>>>> >>>>> >>>>> >>>> >>>> >>>> >>>> >>>> >>>> >>>> >>> >>> >>> >>> >>> >> >> >> >> >> >> > > ________________________________ Message 9 _____________________________________ Time: 07:41:31 AM PST US From: "Pascal" Subject: Re: RV10-List: Painting screws and small parts - what to stick them in - foam? One thing I noticed with test samples is that paint dust will accumulate on the boxes. I do "will call" at ACS so no idea what their boxes are like but I have found that using packing tape over the box holes eliminates any future dust issues. Pascal -------------------------------------------------- From: "Bill Watson" Sent: Friday, October 15, 2010 4:23 AM Subject: Re: RV10-List: Painting screws and small parts - what to stick them in - foam? > > Thanks all. So many solutions, so dull a mind. I'm sure I have a few > ACS boxes lying around. > > Bill > > On 10/14/2010 7:33 PM, Dave Saylor wrote: >> --> RV10-List message posted by: Dave >> Saylor >> >> Poke some holes into a cardboard box with an awl and press the screws >> into the holes. Aircraft Spruce boxes seem to work particularly well... >> >> Dave Saylor >> > > > ________________________________ Message 10 ____________________________________ Time: 08:46:03 AM PST US From: Tim Olson Subject: Re: RV10-List: Re: California Trip - Catalina Island I did see that over the last couple days...and I can report that someone in t he media somewhere needs to update one minor detail in their facts.....the l anding fee now being charges is $25, not $20. I had no idea until I got the re myself a few days ago. Someone in the pattern landed and didn't even kno w there was a fee (clueless I guess...) but they told him too over unicom th at it was $25. Not sure when it changed but I was surprised when all the em ail news things i started receiving still said $20. Anyway, the place is awesome to land at!!! Clouds all below you and just an island in them popping up to land on! I thought I'd have nooooo problem, with 675+ on the RV-10, but with a combin ation of plenty of traffic in the pattern (visible with ads-b!!!), lots of h eat, and the perception, I didn't descend fast enough or had a slightly tigh t pattern and had to slip off a couple hundred extra feet on final. Other than that, it was a breeze. The takeoff was cool as all heck, too! I t just drops off the cliff below you. Sedona, in comparison, was much less complicated, with all the better surrou nding terrain reference. Beautiful area there too. Almost done with the trip now....heading towards home in a couple hours. The write-up may take a week or two but we got some great photos! Tim On Oct 15, 2010, at 5:51 AM, darnpilot@aol.com wrote: > (source AOPA) > > Catalina Island Conservancy officials know a good thing when they see it, a nd have extended a previous two-day offer to waive the $20 Catalina Island l anding fee for AOPA members during AOPA Aviation Summit. Now, the fee is wai ved for four days, Nov. 11 through 14, to cover the entire Summit. > Response to the original offer was strong, so Conservancy officials decide d to extend the offer. Just show your AOPA membership card once you land on t he island, and the fee is waived. Not only that, but you get 20 percent off t he Wildlands Express shuttle service, normally a $17 charge. > Should you happen to buy $10 worth of food at the airport=99s DC-3 G ifts and Grill shop, you=99ll get a free Killer Cookie, so the good ne ws just keeps rolling in. > For those making the trip to Catalina more frequently, such as California p ilots, there is an additional option. Join the new Catalina Aero Club for $1 50 per year, and you=99ll have unlimited free landing privileges. > =9CI am thrilled to see the pilots who make Catalina one of their mo st popular destinations want to redefine their commitment to the protection a nd recreation of the Island through their membership in the new Catalina Aer o Club,=9D said Conservancy President Ann Muscat. > Other benefits to club members include one annual Freewheeler bike pass an d 50 percent off Conservancy campground fees. > Current Conservancy members who would like to upgrade to the Aero Club can do so and extend their membership for $115. Those who are current Leadershi p Circle members can now enjoy unlimited free landings at Airport in the Sky .=94Alton K. Marsh > > > Jeff Darnall > Jacksonville, FL > 904-234-8718 > __i__ > *-----o--o--(_)--o--o-----* > > > > > > > ========================== ========= ========================== ========= ========================== ========= ========================== ========= > ________________________________ Message 11 ____________________________________ Time: 08:50:31 AM PST US From: Tim Olson Subject: Re: RV10-List: fuel valve with position both Also, a side "benefit" to the low wing's limitation against "both" position is that it reinforces better fuel management practices....and allows you to always know the remaining fuel. Anybody notice that the rv-10's with presumably nearly 100% equipage of fuel computers and flow meters, has basically never had an off-airport landing (that we know of) due to poor fuel planning? Let's keep it that way....we have the tools, if we use them. Tim On Oct 15, 2010, at 4:31 AM, Werner Schneider wrote: > > Thanks Linn, > > I agree, on a high wing the fuel pressure is higher, but on a low wing you still pressurize the tanks as well so you should be fine? Unporting would only be possible on a very low fuel level or uncoordinated flight > I plan to add low fuel warnings as well (have them in my Star as we have a SB concerning the same problem). > > Will see if we get deeper into that "why". > > Cheers Werner > > Glastar HB-YKP flying > RV-10 #41122 waiting for shipping > > > On 14.10.2010 22:45, Linn Walters wrote: >> >> No flames. Actually, it's a good question. >> On the high wing, the valve is always under positive fuel pressure (in >> any attitude but inverted .... ;-) ) due to the head .... 5' maybe? >> On the low wing, it would be possible to unport one tank feed ..... and >> suck air. >> Linn >> >> On 10/14/2010 4:32 PM, Werner Schneider wrote: >>> >>> I might open Pandoras box here but it's not about primer so lets try: >>> >>> On my high wing Glastar I have a left/both/right fuel valve and it is >>> used most of the time in the both mode, except when on the ground >>> (crossfeed risk) or on low fuel situations. >>> >>> Now on low wing airplanes I see the left/right only, what is the >>> reason for it (I guess there must be a technical reason behind that)? >>> >>> ok I get my firesuite out before I get the flames >>> >>> Werner >>> >>> >>> >>> >>> >>> >> >> >> >> >> >> >> > > > ________________________________ Message 12 ____________________________________ Time: 09:34:05 AM PST US From: "Stein Bruch" Subject: RE: RV10-List: fuel valve with position both It is possible to have a "both" fuel system, but in low wing planes as others have said it's difficult because the fuel is at/near/below the engine. While at rest gravity would naturally keep the tank levels balanced, in the air it's a different story. It's not just about the tanks being pressurized/vented, but for a "both" selection they need to be pressurized equally. You'll notice that in most high wing airplanes with a both selection, the vents of the two tanks are tied together...in a low wing plane if you didn't have the two tank vents tied together, then one tank will likely have a slightly higher pressure than the other...which mean fuel will be routed from that particular tank and possibly run empty before sucking gas out of the other tank; and you could have an engine sucking air with one wing tank being completely full. It could also cause fuel from one tank to be routed to the other and then overboard. Even though the tanks are vented and "pressurized", it's likely not enough to cause sufficient fuel flow to the engine without and electric or fuel driven pump (which you can get by without on many high wing planes). Remember, we're as much "sucking" the fuel from the tanks as we are pushing when the level of the tanks is below the engine. Anyway, There are ways to do it but none as simple as just doing it the way Van's says. There have been various people who've re-invented the wheel on van's fuel system, but out of the 7000+ flying RV's, the standard way of doing it has been proven as reliable and functional. My 2 cents as usual! Cheers, Stein -----Original Message----- From: owner-rv10-list-server@matronics.com [mailto:owner-rv10-list-server@matronics.com] On Behalf Of Tim Olson Sent: Friday, October 15, 2010 10:46 AM Subject: Re: RV10-List: fuel valve with position both Also, a side "benefit" to the low wing's limitation against "both" position is that it reinforces better fuel management practices....and allows you to always know the remaining fuel. Anybody notice that the rv-10's with presumably nearly 100% equipage of fuel computers and flow meters, has basically never had an off-airport landing (that we know of) due to poor fuel planning? Let's keep it that way....we have the tools, if we use them. Tim On Oct 15, 2010, at 4:31 AM, Werner Schneider wrote: > > Thanks Linn, > > I agree, on a high wing the fuel pressure is higher, but on a low wing you still pressurize the tanks as well so you should be fine? Unporting would only be possible on a very low fuel level or uncoordinated flight > I plan to add low fuel warnings as well (have them in my Star as we have a SB concerning the same problem). > > Will see if we get deeper into that "why". > > Cheers Werner > > Glastar HB-YKP flying > RV-10 #41122 waiting for shipping > > > On 14.10.2010 22:45, Linn Walters wrote: >> >> No flames. Actually, it's a good question. >> On the high wing, the valve is always under positive fuel pressure (in >> any attitude but inverted .... ;-) ) due to the head .... 5' maybe? >> On the low wing, it would be possible to unport one tank feed ..... and >> suck air. >> Linn >> >> On 10/14/2010 4:32 PM, Werner Schneider wrote: >>> >>> I might open Pandoras box here but it's not about primer so lets try: >>> >>> On my high wing Glastar I have a left/both/right fuel valve and it is >>> used most of the time in the both mode, except when on the ground >>> (crossfeed risk) or on low fuel situations. >>> >>> Now on low wing airplanes I see the left/right only, what is the >>> reason for it (I guess there must be a technical reason behind that)? >>> >>> ok I get my firesuite out before I get the flames >>> >>> Werner >>> >>> >>> >>> >>> >>> >> >> >> >> >> >> >> > > > ________________________________ Message 13 ____________________________________ Time: 10:38:37 AM PST US Subject: RV10-List: Re: fuel valve with position both From: "kevino" One other point. I dont have it with me but believe the manual on the air flow performance fuel pump has a specific warning on introducing air into the system could cause an air lock. Kevin Read this topic online here: http://forums.matronics.com/viewtopic.php?p=315860#315860 ________________________________ Message 14 ____________________________________ Time: 11:07:31 AM PST US From: "John Melchert" Subject: RE: RV10-List: fuel valve with position both This can be simply explained with an analogy. Picture yourself with two glasses of beer above your head, with a tube coming out the bottom of both running to a Y and a single tube then running into your mouth. Once you start sucking a little, you'd get some beer, and wouldn't need to suck much more after that (or at all). Essentially both glasses are gravity feeding the single tube, and until they both run empty you'll get a constant flow of beer. Now do the same thing, but put the glasses down to your knees. Nothing is automatically filling the single tube after the Y. In fact, gravity will attempt to equalize the amount in each glass so their levels remain the same, but gravity can't fill the tube running up to your mouth higher than the top level in the glasses down at your knees. You must suck, and continue to do so to get beer. The further from your mouth, the harder you'll need to suck. If you get ahead of gravity's ability to even the glasses, and you empty one of them ahead of the other, your required sucking will suck air (likely a mix of mostly air and some beer). Either way, your required constant flow of beer has been interrupted and that's bad. John Melchert N316PT RV-10 (building, QB fuse) Eden Prairie, MN ________________________________ Message 15 ____________________________________ Time: 11:25:33 AM PST US From: Robin Marks Subject: RE: RV10-List: fuel valve with position both I am grabbing 4 beers and trying this now! Burp, Do Not Archive -----Original Message----- From: owner-rv10-list-server@matronics.com [mailto:owner-rv10-list-server@matronics.com] On Behalf Of John Melchert Sent: Friday, October 15, 2010 11:04 AM Subject: RE: RV10-List: fuel valve with position both This can be simply explained with an analogy. Picture yourself with two glasses of beer above your head, with a tube coming out the bottom of both running to a Y and a single tube then running into your mouth. Once you start sucking a little, you'd get some beer, and wouldn't need to suck much more after that (or at all). Essentially both glasses are gravity feeding the single tube, and until they both run empty you'll get a constant flow of beer. Now do the same thing, but put the glasses down to your knees. Nothing is automatically filling the single tube after the Y. In fact, gravity will attempt to equalize the amount in each glass so their levels remain the same, but gravity can't fill the tube running up to your mouth higher than the top level in the glasses down at your knees. You must suck, and continue to do so to get beer. The further from your mouth, the harder you'll need to suck. If you get ahead of gravity's ability to even the glasses, and you empty one of them ahead of the other, your required sucking will suck air (likely a mix of mostly air and some beer). Either way, your required constant flow of beer has been interrupted and that's bad. John Melchert N316PT RV-10 (building, QB fuse) Eden Prairie, MN ________________________________ Message 16 ____________________________________ Time: 01:17:22 PM PST US From: Dave Saylor Subject: Re: RV10-List: fuel valve with position both > required constant flow of beer has been interrupted<< And I thought running out of gas was bad...that's just unthinkable. Do Not Archive Dave Saylor AirCrafters 140 Aviation Way Watsonville, CA 95076 831-722-9141 Shop 831-750-0284 Cell On Fri, Oct 15, 2010 at 11:04 AM, John Melchert wrote: > > This can be simply explained with an analogy. > > Picture yourself with two glasses of beer above your head, with a tube > coming out the bottom of both running to a Y and a single tube then running > into your mouth. Once you start sucking a little, you'd get some beer, and > wouldn't need to suck much more after that (or at all). Essentially both > glasses are gravity feeding the single tube, and until they both run empty > you'll get a constant flow of beer. > > Now do the same thing, but put the glasses down to your knees. Nothing is > automatically filling the single tube after the Y. In fact, gravity will > attempt to equalize the amount in each glass so their levels remain the > same, but gravity can't fill the tube running up to your mouth higher than > the top level in the glasses down at your knees. You must suck, and > continue to do so to get beer. The further from your mouth, the harder > you'll need to suck. If you get ahead of gravity's ability to even the > glasses, and you empty one of them ahead of the other, your required sucking > will suck air (likely a mix of mostly air and some beer). Either way, your > required constant flow of beer has been interrupted and that's bad. > > John Melchert > N316PT RV-10 (building, QB fuse) > Eden Prairie, MN > > ________________________________ Message 17 ____________________________________ Time: 01:39:05 PM PST US Subject: Re: RV10-List: fuel valve with position both From: Chris Colohan I've not played with the combination of beer and hoses since college -- but in my experience, when you run beer through a funnel and tube, you can get all sorts of vapor lock problems with excessive foaming, no matter if you use gravity or suck it uphill. Perhaps you can avoid these problems by only using fuel that doesn't contain alcohol? :-) Chris On Fri, Oct 15, 2010 at 11:04 AM, John Melchert wrote: > > This can be simply explained with an analogy. > > Picture yourself with two glasses of beer above your head, with a tube > coming out the bottom of both running to a Y and a single tube then running > into your mouth. Once you start sucking a little, you'd get some beer, and > wouldn't need to suck much more after that (or at all). Essentially both > glasses are gravity feeding the single tube, and until they both run empty > you'll get a constant flow of beer. > > Now do the same thing, but put the glasses down to your knees. Nothing is > automatically filling the single tube after the Y. In fact, gravity will > attempt to equalize the amount in each glass so their levels remain the > same, but gravity can't fill the tube running up to your mouth higher than > the top level in the glasses down at your knees. You must suck, and > continue to do so to get beer. The further from your mouth, the harder > you'll need to suck. If you get ahead of gravity's ability to even the > glasses, and you empty one of them ahead of the other, your required > sucking > will suck air (likely a mix of mostly air and some beer). Either way, your > required constant flow of beer has been interrupted and that's bad. > > John Melchert > N316PT RV-10 (building, QB fuse) > Eden Prairie, MN > > ________________________________ Message 18 ____________________________________ Time: 02:02:18 PM PST US From: Werner Schneider Subject: Re: RV10-List: fuel valve with position both Many thanks for the many and valuable comments. A both position would work, if each tank would have a single fuel pump before the fuel valve in the cases described, this would grant a fuel flow secured after unporting and switching valve. I agree left right demands a constant fuel management (which puts more load in difficult situation) but makes a bigger awareness of fuel remaining. A lot of fuel (or beer) for thoughts and good technical arguments. Thanks again to the group for filling that gap of my missing knowledge. I probably will go the Andair fuel pump way as it looks to be the better technology with much less connections then the ES Airflow one. br Werner Glastar HB-YKP flying RV-10 #41122 waiting for shipping On 15.10.2010 18:24, Stein Bruch wrote: > --> RV10-List message posted by: "Stein Bruch" > > It is possible to have a "both" fuel system, but in low wing planes as > others have said it's difficult because the fuel is at/near/below the > engine. While at rest gravity would naturally keep the tank levels > balanced, in the air it's a different story. It's not just about the tanks > being pressurized/vented, but for a "both" selection they need to be > pressurized equally. You'll notice that in most high wing airplanes with a > both selection, the vents of the two tanks are tied together...in a low wing > plane if you didn't have the two tank vents tied together, then one tank > will likely have a slightly higher pressure than the other...which mean fuel > will be routed from that particular tank and possibly run empty before > sucking gas out of the other tank; and you could have an engine sucking air > with one wing tank being completely full. It could also cause fuel from one > tank to be routed to the other and then overboard. Even though the tanks > are vented and "pressurized", it's likely not enough to cause sufficient > fuel flow to the engine without and electric or fuel driven pump (which you > can get by without on many high wing planes). Remember, we're as much > "sucking" the fuel from the tanks as we are pushing when the level of the > tanks is below the engine. > > Anyway, There are ways to do it but none as simple as just doing it the way > Van's says. There have been various people who've re-invented the wheel on > van's fuel system, but out of the 7000+ flying RV's, the standard way of > doing it has been proven as reliable and functional. > > My 2 cents as usual! > > Cheers, > > Stein > ________________________________ Message 19 ____________________________________ Time: 02:26:41 PM PST US From: Linn Walters Subject: Re: RV10-List: fuel valve with position both On 10/15/2010 4:55 PM, Werner Schneider wrote: > > Many thanks for the many and valuable comments. You're welcome. It's why we're here. > A both position would work, if each tank would have a single fuel pump > before the fuel valve in the cases described, this would grant a fuel > flow secured after unporting and switching valve. I see what you mean. Having a pump (actually two) in the wing root at the lowest point would solve the problem that didn't exist before the 'both' position was selected. However, now we've added two pumps (weight), wire (weight) and switches (more weight) to solve a problem that really shouldn't exist. > > I agree left right demands a constant fuel management (which puts more > load in difficult situation) but makes a bigger awareness of fuel > remaining. As I see it, switching tanks every 15 minutes to 1/2 hour is a whole lot safer than turning on the pumps. However, if you'll forget to switch tanks ...... maybe the switches will end up in the same category. From experience, I can tell you that running a tank dry on takeoff (doing T&Gs) in the pattern will get your attention. That was when I was a baby pilot. Another educational experience. > > A lot of fuel (or beer) for thoughts and good technical arguments. I noticed that there are a lot of beer experts on this list. :-D > Thanks again to the group for filling that gap of my missing knowledge. If we really did. > I probably will go the Andair fuel pump way as it looks to be the > better technology with much less connections then the ES Airflow one. Not sure what that means. :-P Best of luck. Linn > > br > > Werner > > Glastar HB-YKP flying > RV-10 #41122 waiting for shipping > > On 15.10.2010 18:24, Stein Bruch wrote: >> --> RV10-List message posted by: "Stein Bruch" >> >> It is possible to have a "both" fuel system, but in low wing planes as >> others have said it's difficult because the fuel is at/near/below the >> engine. While at rest gravity would naturally keep the tank levels >> balanced, in the air it's a different story. It's not just about the >> tanks >> being pressurized/vented, but for a "both" selection they need to be >> pressurized equally. You'll notice that in most high wing airplanes >> with a >> both selection, the vents of the two tanks are tied together...in a >> low wing >> plane if you didn't have the two tank vents tied together, then one tank >> will likely have a slightly higher pressure than the other...which >> mean fuel >> will be routed from that particular tank and possibly run empty before >> sucking gas out of the other tank; and you could have an engine >> sucking air >> with one wing tank being completely full. It could also cause fuel >> from one >> tank to be routed to the other and then overboard. Even though the >> tanks >> are vented and "pressurized", it's likely not enough to cause sufficient >> fuel flow to the engine without and electric or fuel driven pump >> (which you >> can get by without on many high wing planes). Remember, we're as much >> "sucking" the fuel from the tanks as we are pushing when the level of >> the >> tanks is below the engine. >> >> Anyway, There are ways to do it but none as simple as just doing it >> the way >> Van's says. There have been various people who've re-invented the >> wheel on >> van's fuel system, but out of the 7000+ flying RV's, the standard way of >> doing it has been proven as reliable and functional. >> >> My 2 cents as usual! >> >> Cheers, >> >> Stein >> > > ________________________________ Message 20 ____________________________________ Time: 08:49:22 PM PST US From: "Ron McGann" Subject: RV10-List: Totally Off Topic - quadrotor Let me start with an apology - I know this is totally off topic. But I know there are many on the list with an IT and Software Systems Engineering bent with no small interest in the technology behind the electronic systems we have in our planes. The real tech nerds amongst us may find the video below of interest. I find the technology behind the AUTONOMOUS behaviour of this vehicle quite astounding - I have found my next project!! http://www.youtube.com/watch?v=MvRTALJp8DM&feature=player_embedded cheers Ron VH-XRM flying in Oz do not archive ------------------------------------------------------------------------------------- Other Matronics Email List Services ------------------------------------------------------------------------------------- Post A New Message rv10-list@matronics.com UN/SUBSCRIBE http://www.matronics.com/subscription List FAQ http://www.matronics.com/FAQ/RV10-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/rv10-list Browse Digests http://www.matronics.com/digest/rv10-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.