---------------------------------------------------------- Zenith701801-List Digest Archive --- Total Messages Posted Wed 09/17/08: 32 ---------------------------------------------------------- Today's Message Index: ---------------------- 1. 12:17 AM - Re: Re: 801 seat belts (Gary Gower) 2. 05:34 AM - After 5 hours flight time, questions (BokKat) 3. 06:26 AM - Re: After 5 hours flight time, questions (Gordon) 4. 06:42 AM - Re: Shoulder Harness attachment (n85ae) 5. 08:04 AM - Re: Re: Shoulder Harness attachment (Randall J. Hebert) 6. 08:23 AM - Re: Why not just build the fuel system as per the plan (Dan Wilde) 7. 09:03 AM - Re: After 5 hours flight time, questions (BokKat) 8. 09:06 AM - FW: Zenith Gathering (George Race) 9. 10:01 AM - Re: After 5 hours flight time, questions (Gordon) 10. 10:03 AM - Re: Why not just build the fuel system as per the plan (sonar1@cox.net) 11. 10:05 AM - Re: After 5 hours flight time, questions (BokKat) 12. 11:31 AM - Re: Re: Shoulder Harness attachment (Roy Szarafinski) 13. 12:04 PM - Re: Shoulder Harness attachment (n85ae) 14. 12:11 PM - Re: Why not just build the fuel system as per the plan (n85ae) 15. 12:42 PM - fuel flow for CH701 (bob) 16. 12:53 PM - Re: After 5 hours flight time, questions (Gary Gower) 17. 01:09 PM - Re: fuel flow for CH701 (n85ae) 18. 01:33 PM - Re: After 5 hours flight time, questions (Les Goldner) 19. 01:35 PM - Re: After 5 hours flight time, questions (Dan Wilde) 20. 02:10 PM - Re: fuel flow for CH701 (Curt Thompson) 21. 02:17 PM - Re: After 5 hours flight time, questions (Craig Payne) 22. 02:50 PM - Re: After 5 hours flight time, questions (LarryMcFarland) 23. 02:57 PM - Re: FW: Zenith Gathering (Stanley Challgren) 24. 04:33 PM - Re: After 5 hours flight time, questions (Gordon) 25. 06:08 PM - Re: fuel flow for CH701 (Ken Ryan) 26. 06:22 PM - Re: After 5 hours flight time, questions (NYTerminat@aol.com) 27. 06:31 PM - Re: After 5 hours flight time, questions (Craig Payne) 28. 06:49 PM - Re: fuel flow for CH701 (Curt Thompson) 29. 06:53 PM - Re: Re: fuel flow for CH701 (n801bh@netzero.com) 30. 07:01 PM - Re: fuel flow for CH701 (n801bh@netzero.com) 31. 07:17 PM - Re: After 5 hours flight time, questions (NYTerminat@aol.com) 32. 07:54 PM - 801 wing root rib (bcchurch) ________________________________ Message 1 _____________________________________ Time: 12:17:50 AM PST US From: Gary Gower Subject: Re: Zenith701801-List: RE: 801 seat belts (was writing an answer and lost it,- problably touch the sent button?- if not will try one more time, hope is similar... or better) - Hello Joe, - Nothing,- no harm at all, maybe that you will not be satisfied with only the bracket,- then will reinforce something else, until the plane will be over weight.--- - We all build our airplanes to enjoy them and fly them the best we can.- - - When we choose to fly in good weather (do our weather breifing and flight p lanning), the-airplane and the engine has-good mantainance, fuel -tan ks at take off with enough fuel for the trip and plenty of reserve, made a correct prefight (with the card in hand), we take off and land the best we can, we had a good instructor and fly and practice our skills as if "that" instructor was always at our right seat.- - Chance are that "this"-pilot will need more the safety belts of his car t han in his-airplane. 1,000's of old retired pilots to proof it.-- - Yes, I know that accidents happen (most movies have an- airplane crash sc ene, ask the ladies in the grocery store), but I gladly take the risk to dr ive to and from -my airdrome- (about one hour drive each way, depends o n traffic) to enjoy the-safety of a good week end flight in my 701 STOL. - - Sadly in my life.- I have lost more friends in car an other related accid ents that flying.- One- of them just driving home-from a bar with iro n safety belt brackets and air bags. - Saludos Gary- Gower "El tama=F1o del candado es proporcional con el miedo al robo."- "The size of the padlock is proportional with the fear to the robbery." Archive if you want :-)- :-) --- On Wed, 9/17/08, Joemotis@aol.com wrote: From: Joemotis@aol.com Subject: Re: Zenith701801-List: RE: 801 seat belts In a message dated 9/16/2008 8:51:48 P.M. Pacific Daylight Time, ggower_99@ yahoo.com writes: (in Spanish is exponencial). In English is exponential. If you want to make the bracket Bigger, thicker, longer and stronger and to clarify I am NOT an Engineer, what's the worst possible harm? - Joe Motis - No Archivos, Eh -=0A=0A=0A ________________________________ Message 2 _____________________________________ Time: 05:34:50 AM PST US From: "BokKat" Subject: Zenith701801-List: After 5 hours flight time, questions 1) Just wondering what kind of indicated airspeed everyone is getting. I',m only getting about 70mph with a Rotax 912 ULS woodcomp prop at about 5400 rpm's. Is this normal or is my airspeed indicator off? Haven't had a chance to check it yet. 2) With slow flight and apporach to landing something clatters and bangs back in the fuselge, presumably oil canning. Normal? I checked everything else and nothing is loose. 3) Yesterday my engine faltered under full throttle and climb out and immediately got better when throttled back. On my Dynon monitor a Low Fuel Pressure warning popped up and it showed only about 1.9 to 2 psi, yet fuel flow was 5 gallons per hour. I returned home and checked the fuel flow and there is plenty of unobstructed flow as far as the front of the firewall anyway. I have a gascolater in front of the firewall that I'll check and clean today. The fuel pressure and fuel flow senders spliced into the line shouldn't obstruct the flow. On the ground at idle it is about 3 - 3.5 psi. Any ideas? It seems to run itself out of gas past about 5400rpm!?! 4) I was just getting used to the pitch sensitivity of the elevator and recieved the VG's from JG (in only a week! Send them via SST or SR-71?) Put them on the elevator and wow!! Almost too much sensitivity! It throws itself into the air and I found I have to be ready for it. Still in the learning curve of flying it, so haven't really done much testing of things yet. Mainly getting it up and down comfortably at this point. ________________________________ Message 3 _____________________________________ Time: 06:26:03 AM PST US From: "Gordon" Subject: Re: Zenith701801-List: After 5 hours flight time, questions I have the same engine and prop and cruise at 4400 rpm (nice and quiet and low fuel burn) and show about 78mph + or minus depending on gross weight, turbulence and if I'm paying attention. This is on my Dynon and conventional ASI, both are within a MPH of each other. I get the same clatter in slow flight. In my case it's the back of the baggage compartment that starts oil canning and banging at about 50mph. Can't comment on the fuel issues -- I haven't had any. Gordon ----- Original Message ----- From: BokKat To: zenith701801-list@matronics.com Sent: Wednesday, September 17, 2008 8:34 AM Subject: Zenith701801-List: After 5 hours flight time, questions 1) Just wondering what kind of indicated airspeed everyone is getting. I',m only getting about 70mph with a Rotax 912 ULS woodcomp prop at about 5400 rpm's. Is this normal or is my airspeed indicator off? Haven't had a chance to check it yet. 2) With slow flight and apporach to landing something clatters and bangs back in the fuselge, presumably oil canning. Normal? I checked everything else and nothing is loose. 3) Yesterday my engine faltered under full throttle and climb out and immediately got better when throttled back. On my Dynon monitor a Low Fuel Pressure warning popped up and it showed only about 1.9 to 2 psi, yet fuel flow was 5 gallons per hour. I returned home and checked the fuel flow and there is plenty of unobstructed flow as far as the front of the firewall anyway. I have a gascolater in front of the firewall that I'll check and clean today. The fuel pressure and fuel flow senders spliced into the line shouldn't obstruct the flow. On the ground at idle it is about 3 - 3.5 psi. Any ideas? It seems to run itself out of gas past about 5400rpm!?! 4) I was just getting used to the pitch sensitivity of the elevator and recieved the VG's from JG (in only a week! Send them via SST or SR-71?) Put them on the elevator and wow!! Almost too much sensitivity! It throws itself into the air and I found I have to be ready for it. Still in the learning curve of flying it, so haven't really done much testing of things yet. Mainly getting it up and down comfortably at this point. ________________________________ Message 4 _____________________________________ Time: 06:42:17 AM PST US Subject: Zenith701801-List: Re: Shoulder Harness attachment From: "n85ae" Cal - I would think your common sense would be telling you that, having your seatbelt attached to something that might break is a bad thing. If you really think it is plenty strong, then you're more than welcome to to build it per the plans. Regards, Jeff Read this topic online here: http://forums.matronics.com/viewtopic.php?p 4760#204760 ________________________________ Message 5 _____________________________________ Time: 08:04:30 AM PST US Subject: RE: Zenith701801-List: Re: Shoulder Harness attachment From: "Randall J. Hebert" Cal and Jeff I too am a structural engineer. In buildings and general structures. In my experience when my client perceives that something is inadequate, no matter how hard I try to convince them that I am correct, in their minds it is inadequate. Perception plays a big part in this discussion. Jeff can probably relate to this. Although I am not an Aeronautical Engineer, Structural Engineering relates to calculation of loadings and stress analysis in any structure. Loads in these aircraft are of a small magnitude thus aluminum structures. Jeff the high G loading are probably out of the design criteria of these aircraft. It is like designing a building here in S Louisiana for a 150mph wind when the statistical wind speeds are 110 mph. (90mph thanks to Gustav) The problem I see here is that more is not always better. Increasing a parts strength can move a failure regime to another part causing other types of failures to occur. Thanks to both of you guys for bringing this issue up however, because I will now look more closely at this area when I get to it. Randall J Hebert Randall J Hebert & Associates, Inc Consulting Engineers Ph 337-261-1976 Fx 337-261-1977 Cal - I would think your common sense would be telling you that, having your seatbelt attached to something that might break is a bad thing. If you ________________________________ Message 6 _____________________________________ Time: 08:23:12 AM PST US From: Dan Wilde Subject: Re: Zenith701801-List: Why not just build the fuel system as per the plan Brett Hanley wrote: > I have not heard of any problem building the fuel system as per the > plan. What are we hoping to gain by changes? Speed? Simplicity? Save > money? Gain weight? I just do not see the need for modifications. > > Brett Hanley > N858BH > 701/ Subaru EA81 > 40 hours > Hilltown PA > > * > > _* I built mine as per plan. No problems after 30 hours. Dan Wilde N948DW Do not archive ________________________________ Message 7 _____________________________________ Time: 09:03:14 AM PST US From: "BokKat" Subject: Re: Zenith701801-List: After 5 hours flight time, questions Wow, you must have your prop adjusted pretty coarse. Mine's probably too far the other way. I checked and was able to oil can the back of the baggage compartment and also the belly hatch. Maybe an L angle stiffener added here will "can" the noise! Thanks for the suggestions. ----- Original Message ----- From: Gordon To: zenith701801-list@matronics.com Sent: Wednesday, September 17, 2008 8:25 AM Subject: Re: Zenith701801-List: After 5 hours flight time, questions I have the same engine and prop and cruise at 4400 rpm (nice and quiet and low fuel burn) and show about 78mph + or minus depending on gross weight, turbulence and if I'm paying attention. This is on my Dynon and conventional ASI, both are within a MPH of each other. I get the same clatter in slow flight. In my case it's the back of the baggage compartment that starts oil canning and banging at about 50mph. Can't comment on the fuel issues -- I haven't had any. Gordon ----- Original Message ----- From: BokKat To: zenith701801-list@matronics.com Sent: Wednesday, September 17, 2008 8:34 AM Subject: Zenith701801-List: After 5 hours flight time, questions 1) Just wondering what kind of indicated airspeed everyone is getting. I',m only getting about 70mph with a Rotax 912 ULS woodcomp prop at about 5400 rpm's. Is this normal or is my airspeed indicator off? Haven't had a chance to check it yet. 2) With slow flight and apporach to landing something clatters and bangs back in the fuselge, presumably oil canning. Normal? I checked everything else and nothing is loose. 3) Yesterday my engine faltered under full throttle and climb out and immediately got better when throttled back. On my Dynon monitor a Low Fuel Pressure warning popped up and it showed only about 1.9 to 2 psi, yet fuel flow was 5 gallons per hour. I returned home and checked the fuel flow and there is plenty of unobstructed flow as far as the front of the firewall anyway. I have a gascolater in front of the firewall that I'll check and clean today. The fuel pressure and fuel flow senders spliced into the line shouldn't obstruct the flow. On the ground at idle it is about 3 - 3.5 psi. Any ideas? It seems to run itself out of gas past about 5400rpm!?! 4) I was just getting used to the pitch sensitivity of the elevator and recieved the VG's from JG (in only a week! Send them via SST or SR-71?) Put them on the elevator and wow!! Almost too much sensitivity! It throws itself into the air and I found I have to be ready for it. Still in the learning curve of flying it, so haven't really done much testing of things yet. Mainly getting it up and down comfortably at this point. href="http://www.matronics.com/Navigator?Zenith701801-List">http://www. matronics.com/Navigator?Zenith701801-List href="http://forums.matronics.com">http://forums.matronics.com href="http://www.matronics.com/contribution">http://www.matronics.com/c ________________________________ Message 8 _____________________________________ Time: 09:06:17 AM PST US From: "George Race" Subject: Zenith701801-List: FW: Zenith Gathering Can someone please help Mark out? George -----Original Message----- From: zodierocket@hsfx.ca [mailto:zodierocket@hsfx.ca] Sent: Wednesday, September 17, 2008 9:19 AM Subject: Zenith Gathering Hi George, could you do me a favor please. I came down to the open house early and forgot to bring a Olfa P-800 Knife for my Forum on Friday. Could you ask the lists if there is anyone who is attending on Friday if they can bring me a knife, used or new would be fine. I am trying to find one locally, but don't expect to much success finding one here in Mexico, Missouri. Thanks Mark Townsend Can-Zac Aviation. ________________________________ Message 9 _____________________________________ Time: 10:01:12 AM PST US From: "Gordon" Subject: Re: Zenith701801-List: After 5 hours flight time, questions I set the prop according to the woodcomp instructions. 5450 static rpm --- it leaps off the ground in a very short distance. ----- Original Message ----- From: BokKat To: zenith701801-list@matronics.com Sent: Wednesday, September 17, 2008 12:02 PM Subject: Re: Zenith701801-List: After 5 hours flight time, questions Wow, you must have your prop adjusted pretty coarse. Mine's probably too far the other way. I checked and was able to oil can the back of the baggage compartment and also the belly hatch. Maybe an L angle stiffener added here will "can" the noise! Thanks for the suggestions. ----- Original Message ----- From: Gordon To: zenith701801-list@matronics.com Sent: Wednesday, September 17, 2008 8:25 AM Subject: Re: Zenith701801-List: After 5 hours flight time, questions I have the same engine and prop and cruise at 4400 rpm (nice and quiet and low fuel burn) and show about 78mph + or minus depending on gross weight, turbulence and if I'm paying attention. This is on my Dynon and conventional ASI, both are within a MPH of each other. I get the same clatter in slow flight. In my case it's the back of the baggage compartment that starts oil canning and banging at about 50mph. Can't comment on the fuel issues -- I haven't had any. Gordon ----- Original Message ----- From: BokKat To: zenith701801-list@matronics.com Sent: Wednesday, September 17, 2008 8:34 AM Subject: Zenith701801-List: After 5 hours flight time, questions 1) Just wondering what kind of indicated airspeed everyone is getting. I',m only getting about 70mph with a Rotax 912 ULS woodcomp prop at about 5400 rpm's. Is this normal or is my airspeed indicator off? Haven't had a chance to check it yet. 2) With slow flight and apporach to landing something clatters and bangs back in the fuselge, presumably oil canning. Normal? I checked everything else and nothing is loose. 3) Yesterday my engine faltered under full throttle and climb out and immediately got better when throttled back. On my Dynon monitor a Low Fuel Pressure warning popped up and it showed only about 1.9 to 2 psi, yet fuel flow was 5 gallons per hour. I returned home and checked the fuel flow and there is plenty of unobstructed flow as far as the front of the firewall anyway. I have a gascolater in front of the firewall that I'll check and clean today. The fuel pressure and fuel flow senders spliced into the line shouldn't obstruct the flow. On the ground at idle it is about 3 - 3.5 psi. Any ideas? It seems to run itself out of gas past about 5400rpm!?! 4) I was just getting used to the pitch sensitivity of the elevator and recieved the VG's from JG (in only a week! Send them via SST or SR-71?) Put them on the elevator and wow!! Almost too much sensitivity! It throws itself into the air and I found I have to be ready for it. Still in the learning curve of flying it, so haven't really done much testing of things yet. Mainly getting it up and down comfortably at this point. href="http://www.matronics.com/Navigator?Zenith701801-List">http://www. matronics.com/Navigator?Zenith701801-List href="http://forums.matronics.com">http://forums.matronics.com href="http://www.matronics.com/contribution">http://www.matronics.com/c href="http://www.matronics.com/Navigator?Zenith701801-List">http://www. matronics.com/Navigator?Zenith701801-List href="http://forums.matronics.com">http://forums.matronics.com href="http://www.matronics.com/contribution">http://www.matronics.com/c ________________________________ Message 10 ____________________________________ Time: 10:03:16 AM PST US Subject: Zenith701801-List: Re: Why not just build the fuel system as per the plan From: "sonar1@cox.net" Brett: I didn't like having one full tank and one empty tank on landing, and having no control over it. At the minimum I would suggest putting an accessible valve in each line. Bubbles in the lines were my problem. One bubble will stop the flow. I also put in an ACS gascolator on the firewall - at least it has a screen - and am very happy with that. Those who are putting in header tanks are really complicating everything. I would never do that. Fred........N9701 do not archive Read this topic online here: http://forums.matronics.com/viewtopic.php?p 4794#204794 ________________________________ Message 11 ____________________________________ Time: 10:05:18 AM PST US From: "BokKat" Subject: Re: Zenith701801-List: After 5 hours flight time, questions That's what I set mine! Wonder where my speed is gong? Eyeballing outside I thought I was going about the same speed as my Kitfox. Is there a setting on the Dynon? If all else fails I'll have to read the directions. Ha! Thanks ----- Original Message ----- From: Gordon To: zenith701801-list@matronics.com Sent: Wednesday, September 17, 2008 12:00 PM Subject: Re: Zenith701801-List: After 5 hours flight time, questions I set the prop according to the woodcomp instructions. 5450 static rpm --- it leaps off the ground in a very short distance. ----- Original Message ----- From: BokKat To: zenith701801-list@matronics.com Sent: Wednesday, September 17, 2008 12:02 PM Subject: Re: Zenith701801-List: After 5 hours flight time, questions Wow, you must have your prop adjusted pretty coarse. Mine's probably too far the other way. I checked and was able to oil can the back of the baggage compartment and also the belly hatch. Maybe an L angle stiffener added here will "can" the noise! Thanks for the suggestions. ----- Original Message ----- From: Gordon To: zenith701801-list@matronics.com Sent: Wednesday, September 17, 2008 8:25 AM Subject: Re: Zenith701801-List: After 5 hours flight time, questions I have the same engine and prop and cruise at 4400 rpm (nice and quiet and low fuel burn) and show about 78mph + or minus depending on gross weight, turbulence and if I'm paying attention. This is on my Dynon and conventional ASI, both are within a MPH of each other. I get the same clatter in slow flight. In my case it's the back of the baggage compartment that starts oil canning and banging at about 50mph. Can't comment on the fuel issues -- I haven't had any. Gordon ----- Original Message ----- From: BokKat To: zenith701801-list@matronics.com Sent: Wednesday, September 17, 2008 8:34 AM Subject: Zenith701801-List: After 5 hours flight time, questions 1) Just wondering what kind of indicated airspeed everyone is getting. I',m only getting about 70mph with a Rotax 912 ULS woodcomp prop at about 5400 rpm's. Is this normal or is my airspeed indicator off? Haven't had a chance to check it yet. 2) With slow flight and apporach to landing something clatters and bangs back in the fuselge, presumably oil canning. Normal? I checked everything else and nothing is loose. 3) Yesterday my engine faltered under full throttle and climb out and immediately got better when throttled back. On my Dynon monitor a Low Fuel Pressure warning popped up and it showed only about 1.9 to 2 psi, yet fuel flow was 5 gallons per hour. I returned home and checked the fuel flow and there is plenty of unobstructed flow as far as the front of the firewall anyway. I have a gascolater in front of the firewall that I'll check and clean today. The fuel pressure and fuel flow senders spliced into the line shouldn't obstruct the flow. On the ground at idle it is about 3 - 3.5 psi. Any ideas? It seems to run itself out of gas past about 5400rpm!?! 4) I was just getting used to the pitch sensitivity of the elevator and recieved the VG's from JG (in only a week! Send them via SST or SR-71?) Put them on the elevator and wow!! Almost too much sensitivity! It throws itself into the air and I found I have to be ready for it. Still in the learning curve of flying it, so haven't really done much testing of things yet. Mainly getting it up and down comfortably at this point. href="http://www.matronics.com/Navigator?Zenith701801-List">http://www. matronics.com/Navigator?Zenith701801-List href="http://forums.matronics.com">http://forums.matronics.com href="http://www.matronics.com/contribution">http://www.matronics.com/c href="http://www.matronics.com/Navigator?Zenith701801-List">http://www. matronics.com/Navigator?Zenith701801-List href="http://forums.matronics.com">http://forums.matronics.com href="http://www.matronics.com/contribution">http://www.matronics.com/c href="http://www.matronics.com/Navigator?Zenith701801-List">http://www. matronics.com/Navigator?Zenith701801-List href="http://forums.matronics.com">http://forums.matronics.com href="http://www.matronics.com/contribution">http://www.matronics.com/c ________________________________ Message 12 ____________________________________ Time: 11:31:57 AM PST US From: Roy Szarafinski Subject: Re: Zenith701801-List: Re: Shoulder Harness attachment Gents, I am not an engineer but have a fair understanding of physics and many other things. This pertains to the 701, as I have no experience with the 801. The 701 was designed for the standard pilot, 5'6" 165 lbs or something close to that. Being 6'2" and 220 lbs puts me somewhat outside the design parameters of the restraint system ( a 150 mph breeze on a structure with 110 mph hurricane ties). With this in mind I am abandoning the three point harness in favor of a four point, my idea is to install a .025 hat section in the roof of the baggage area from front to rear intersecting at the center of the rear wing attach top channel, incorporating shear doublers at the harness attach point, this should address upper torso restraint adequately in conjunction with the existing upper harness mount. To a degree this will lessen the load on the three existing load points, however the weak link is still the tunnel. Zac addresses this with a doubler design for the tunnel. While this may be perfectly adequate I think it can be improved upon by an .040 attach point riveted to the top of the gear channel and tying into the existing tunnel restraint attach with a 3/16 cable. The outer lap belt restraint point can be doubled to the cabin side wall. I am hesitant to attach anything to the gear structure in the event it shears and departs, so the size and number of rivets need to be minimum for the gear channel modification I propose. I envision this type of failure mode (gear departing) to place the gear channel rivet heads in bearing stress while a frontal impact would place these same rivets in shear. By rough estimation not including the harness it would add less than 2 pounds. Indeed more may not be better and may indeed move a failure regime to another part causing other types of failure but in the event these proposed modifications ever come into play, failure of some sort, has already occurred. The last thing I want to do is to design in a fatal flaw or perish because of an inadequately sized restraint system. All responses welcome. Roy Szarafinski 701 plans roysgarage.com ----- Original Message ---- From: Randall J. Hebert Sent: Wednesday, September 17, 2008 10:58:06 AM Subject: RE: Zenith701801-List: Re: Shoulder Harness attachment In my experience when my client perceives that something is inadequate, no matter how hard I try to convince them that I am correct, in their minds it is inadequate. Perception plays a big part in this discussion. Jeff can probably relate to this. Loads in these aircraft are of a small magnitude thus aluminum structures. Jeff the high G loading are probably out of the design criteria of these aircraft. It is like designing a building here in S Louisiana for a 150mph wind when the statistical wind speeds are 110 mph. (90mph thanks to Gustav) The problem I see here is that more is not always better. Increasing a parts strength can move a failure regime to another part causing other types of failures to occur. ________________________________ Message 13 ____________________________________ Time: 12:04:07 PM PST US Subject: Zenith701801-List: Re: Shoulder Harness attachment From: "n85ae" It looks weak to me, so I'm making it stronger. Jeff Read this topic online here: http://forums.matronics.com/viewtopic.php?p 4812#204812 ________________________________ Message 14 ____________________________________ Time: 12:11:59 PM PST US Subject: Zenith701801-List: Re: Why not just build the fuel system as per the plan From: "n85ae" I built and fly a Kitfox with an Injected Continental IO-240B, with a header tank. It's a very simple arrangement, and the header gives you a lot of benefit. For example. in a headerless system in a steep descent, if you for example get some air in the fuel lines when the fuel feeds are exposed to air. Your engine quits. This does not happen with a header. If you want to switch main tanks in flight the header prevent fuels flow interruptions from stopping the engine. If you have a header low sensor in the header, you have a bit of warning before your engine will actually quit (dependant on header volume). Regards, Jeff Read this topic online here: http://forums.matronics.com/viewtopic.php?p 4816#204816 ________________________________ Message 15 ____________________________________ Time: 12:42:15 PM PST US From: "bob" Subject: Zenith701801-List: fuel flow for CH701 Study of the Zenith CH701 two tank fuel system, Bob Kissell, N701UB After completing my Zenith CH701 with two wing tanks I discovered on my first cross country flight that I had unbalanced fuel burn. The fuel system in my aircraft is built per the Zenith drawings, which is comprised of two ten gallon tanks, one in each wing that are connected together at the gascolator located at the low point in the system. This anomaly set about an investigation to explain this event and predict what would happen if one tank ran dry before the other To answer these questions several tests were devised and conducted. The first test was to determine if fuel would be supplied from a tank with fuel, when the other tank is empty. The test was devised using the following logic. The Rotax 912ULS that my aircraft uses, can under the most demanding throttle setting use fuel at no more than 6.5 gallons/hr.. This information is available from the Rotax engine specifications. The fuel in the Zenith design is pumped (drawn) from the gascolator to the engine. I propose that if the natural gravity flow from the tank to the gascolator can supply fuel at a rate that exceeds the engine demand then the fuel pump never draws fuel from the tank(s), it really just lifts fuel from the gascolator to the carb's and the fuel flows by gravity from the tank(s) to replace the fuel lifted. This is perhaps a different way to look at the Zenith system but I found it made the problem tractable for me. The fuel system in my aircraft is built per the Zenith drawings, which is comprised of two ten gallon tanks, one in each wing that are connected together at the gascolator located at the low point in the system. The fuel system uses =BC" ID fuel lines and I have added a fuel filter in each wing root. The goal of the test was to determine how much fuel could flow from a single tank and out the gascolator and compare that rate to the worst case demand of the 100 HP Rotax. Note it really takes two people to do this test safely. Both fuel lines from left and right tanks were pinched off by use of two clamps and the cockpit fuel shutoff was switched off. The drain fitting from the bottom of the gascolator was then removed. A small funnel placed into an empty water bottle that could hold 16.9 ounces and was used to catch the fuel. A stop watch was used to measure how long it took to fill the bottle after one of the clamps was removed. This process was repeated for the other tank as well. The flow was able to fill the 16.9 ounce bottle in 30 seconds. Since there is 128 ounces of fuel in a gallon this flow rate indicates a flow of 15.84 gallons/hr from a single tank. The other tank resulted in a similar flow rate. This test proved to me that fuel flow to the gascolator from even one tank could easily keep pace with the fuel demand of the engine. In fact if one tank is empty, the flow from the other could supply the engine and the difference flow into the other tank. This test still did not answer why I had experienced uneven fuel burn. To answer that question another test was conducted with some simple math. The Zenith design uses fuel tank caps that are vented around the edge of the cap. I had wondered if a pressure difference was developing in the tanks that influenced fuel flow. To determine this I drilled holes thru the top of the caps and inserted =BC" tubing which ran into the cockpit and connected to a water manometer. This enabled me to measure the differential tank pressure in flight. In level cruise flight at 78 mph IAS, the right tank measured -2.875 inch of water and left measured -2.25 inch of water. This converts to pressures of (right) -0.10386 PSI and (left) -0.08129 PSI. The difference pressure is 0.0226 PSI, since fuel weighs 0.02597 lbs/inch, the fuel head required to equal this pressure is 0.869 inch. The fuel level difference required amounts to less than 1". This result suggest that pressure difference was not the dominate term in my unbalanced fuel burn. It was notable that the pressures on the tanks were negative. A snorkel vent was constructed and tested at 70 mph and found to produce about 0.1 PSI. Each fuel cap was modified with a snorkel vent facing the slip stream to pressurize each tank to a positive pressure of 0.1 PSI. I will now explain the importance of this pressure if it exists. In a perfect world the pressure above both tanks would be equal and any difference in fuel height (head) would result in fuel flowing from the higher tank, through the gascolator then into the tank with the lower fuel level. This would continue until the level of both tanks was equal. If a slight pressure was applied above the fuel level to one tank then the level fuel would flow from the pressurized tank to the unpressurized tank until a fuel head develops an opposing pressure equal the pressurized tank. Keep in mind that as fuel flows from the source tank the level drops and the level in the other rises, so the head that must develop in the tank is really only half of the total required, since half is a rise in one tank, while half is a drop in the other. To understand how a slight pressure can create a problem, a little math is needed. Gasoline weighs 6 pounds per gallon and there is 231 cubic inches in a gallon. Thus an inch of gas weighs 6/231 pounds or 0.02597 pounds per cubic inch and would exert 0.02597 PSI on the bottom of the tank. If a pressure difference between the tanks were to develop of say 0.2 PSI, which doesn't seem like much, it would take (0.2)/(0.02597) or 7.7 inches of fuel head to equal this pressure. To develop this head requires that the fuel flow from one tank into the other until the head pressure matches the offending tank pressure. One can easily see that in the case when both tanks start out full, such as at the beginning of a cross county, that fuel pushed into the already full tank must vent overboard. Also to develop the required head the pressured tank must lose all of the fuel head. This is because no additional head can develop in a full tank. It's not really as bad as this would suggest, because while this is occurring, fuel is being burned which creates room for this head to develop without continued fuel loss. This simple analysis indicates the importance of minimizing the difference pressure between two tanks. The best way to do this is to add a vent tube that connects the top of both tanks together and use two vented caps. I did not know about this problem until I had completed my aircraft so it was too late for me to do this. For you builders that are still building your wings, I would recommend that you modify your tanks and add a hose fitting to the top of each tank. Then when plumbing your aircraft run a fuel grade hose between the two tanks. Back to my problem, the manometer test I conducted indicated that a slight pressure difference did exist between tanks and contributes to uneven fuel burn. I added snorkel vents to both caps to create a slight positive pressure of near equal value on both tanks to minimize the difference pressure. So long as a bug doesn't plug one of my vents things should work fine. The conclusions I have reached are thus, the Zenith fuel system which ties both tanks together will supply needed fuel, even if one tank runs dry before the other. This is because the supply line is able to flow fuel to the gascolator at 15.8 gallons/hour and the engine only requires at most 6.5 gallons/hour. Since there is excess fuel flow capability the two tanks will try to remain equal in level and can do so providing there is not a significant difference in pressure above the tanks. The difference pressure should probably not exceed more than about 0.1 PSI (3.3 inches of fuel head). The best way to minimize the pressure difference is to have a common vent line that connects the two tanks together above the fuel level. Also it would be wise to have vents in both caps so that if one were plugged there is a redundant vent. If any of you builders out there have arrived at a different conclusion please post or send me you efforts. I would really like to put this to bed so I can fly safe and have peace of mind regarding this problem. Hope this is not to long for you all, sorry if it is but I wanted to get it all out there for consideration and opinions... Thanks..Bob Kissell ________________________________ Message 16 ____________________________________ Time: 12:53:19 PM PST US From: Gary Gower Subject: Re: Zenith701801-List: After 5 hours flight time, questions Probably other 701 pilots have noticed this: - Keep the-oil--canning, -is a cheap and "automatic"-built in- St all and- Slip "alarm" in the 701,-- is a free bonus from ZAC no other airplane has- that makes it extra safe.... - Try to keep the ball centered always when flying and the-low speed -bet wen 50 and 60 mph- (with or without 15=B0 of flaps)- when doing your ap proach and the "alarm" will not sound.--- When I flair to land I can lower the speed a lot more, but I have not notic ed any alarm, probably I am too focused in my landing to hear it.- :-) - Also I have noticed that keeping-the ball centered I have an extra Bonus: - About- more than 5 mph increase in cruise speed-over the "alarm" sp eed...- ;-) - As my Instructor--told me -always in my student hours:- "keep the b all centered"-- also a favorite from him was:- I want 60, NOT- 59 -or 61 only 60"--- If I had recieve my instruction in the 701 he mi ght-only say:- "Keep that oil canning off"- :-)- :-) - Just my personal experience. - About the post also,- I have my pitch set for 87 mph at 5,000 rpm cruise - (normally over 6,500 + ft ASL) moved the pitch a little at a time until got it set, cant remember the fina l degress of pitch, but was a little (like a milimeter) at a time. . - Saludos Gary Gower Flying from Chapala,- Mexico 701 912S- 200 + hrs. Building a 601 XL Jab 3300.- "Hope will also have the "alarm" built in..."- - --- On Wed, 9/17/08, BokKat wrote: From: BokKat Subject: Re: Zenith701801-List: After 5 hours flight time, questions Wow, you must have your prop adjusted pretty coarse.- Mine's probably too far the other way. I checked and was able to oil can the back of the baggage compartment and a lso the belly hatch.- Maybe an L angle stiffener added here will "can" th e noise! Thanks for the suggestions. ----- Original Message ----- From: Gordon Sent: Wednesday, September 17, 2008 8:25 AM Subject: Re: Zenith701801-List: After 5 hours flight time, questions I have the same engine and prop and cruise at 4400 rpm (nice and quiet and low fuel burn) and show about 78mph + or minus depending on gross weight, t urbulence and if I'm paying attention. This is on my Dynon and conventional ASI, both are within a MPH of each other.- I get the same clatter in slow flight. In my case it's the back of the bagg age compartment that starts oil canning and banging at about 50mph. Can't comment on the fuel issues -- I haven't had any. Gordon-- ----- Original Message ----- From: BokKat Sent: Wednesday, September 17, 2008 8:34 AM Subject: Zenith701801-List: After 5 hours flight time, questions 1) Just wondering what kind of indicated airspeed everyone is getting.- I ',m only getting about 70mph with a Rotax 912 ULS woodcomp prop at about 54 00 rpm's.- Is this normal or is my airspeed indicator off?- Haven't had a chance to check it yet. 2) With slow flight and apporach to landing something clatters and bangs ba ck in the fuselge, presumably oil canning.- Normal?- I checked everythi ng else and nothing is loose. 3)- Yesterday my engine faltered under full throttle and climb out and im mediately got better when throttled back.- On my Dynon monitor a Low Fuel Pressure warning popped up and it showed only about 1.9 to 2 psi, yet fuel flow was 5 gallons per hour.- I returned home and checked the fuel flow and there is plenty of unobstructed flow as far as the front of the firewal l anyway.- I have a gascolater in front of the firewall that I'll check a nd clean today.- The fuel pressure and fuel flow senders spliced into the line shouldn't obstruct the flow.- On the ground at idle it is about 3 - 3.5 psi.- Any ideas?- It seems to run itself out of gas past about 540 0rpm!?! 4) I was just getting used to the pitch sensitivity of the elevator and rec ieved the VG's from JG (in only a week! Send them via SST or SR-71?)- Put them on the elevator and wow!!- Almost too much sensitivity!- It throw s itself into the air and I found I have to be ready for it. Still in the learning curve of flying it, so haven't really done much testi ng of things yet.- Mainly getting it up and down comfortably at this poin t. href="http://www.matronics.com/Navigator?Zenith701801-List">http://www.ma tronics.com/Navigator?Zenith701801-List href="http://forums.matronics.com">http://forums.matronics.com href="http://www.matronics.com/contribution">http://www.matronics.com/c href="http://www.matronics.com/Navigator?Zenith701801-List">http://www.ma tronics.com/Navigator?Zenith701801-List href="http://forums.matronics.com">http://forums.matronics.com href="http://www.matronics.com/contribution">http://www.matronics.com/c =0A=0A=0A ________________________________ Message 17 ____________________________________ Time: 01:09:24 PM PST US Subject: Zenith701801-List: Re: fuel flow for CH701 From: "n85ae" Great post, and a good experiment! That's exactly what my experience with my Kitfox has been as well. It's easy to discount the effects of the vents, and the vent plumbing but it is a very real phenomenon. Have ground tested my fuel flow from both tanks and they are very close, but in flight is a different matter. Even in carefully coordinated flight I get uneven flow. I think there's one 801 crashed when fuel flow stopped, which makes me very suspicious of the stock caps as the culprit. Jeff Read this topic online here: http://forums.matronics.com/viewtopic.php?p 4826#204826 ________________________________ Message 18 ____________________________________ Time: 01:33:03 PM PST US From: "Les Goldner" Subject: RE: Zenith701801-List: After 5 hours flight time, questions BokKat, I also have 100-hp 912ULS engine but have a 3-blade Warpdrive prop. I set the pitch several times and found that if I let the static (tied-down) RPM go to 5400, I get bad fuel economy and slower cruise that at 5100 (a higher pitch). With this setting, at about 4900-RPM, I get better than 5-GPH and cruise at about 79-MPH under near standard conditions at 1000'. I can fly as low as 4000-RPM and get about 3-GPH. I suggest you increase your prop pitch and see how this impacts your speed and fuel flow. Regarding your fuel flow problem; since you plane is new its very possible your fuel filter has some construction junk in it that constricts your fuel flow only at peak draw. If so, this should be easy to fix. Also check to see if crud got into your gascolator gas. If the filters and gascolator are clean, you may also need to check the carb jets and float bowls for crud. Another possibility is that the holes you drilled in your gas caps are too small or not properly placed. I hope this helps, Les _____ From: owner-zenith701801-list-server@matronics.com [mailto:owner-zenith701801-list-server@matronics.com] On Behalf Of BokKat Sent: Wednesday, September 17, 2008 5:34 AM Subject: Zenith701801-List: After 5 hours flight time, questions 1) Just wondering what kind of indicated airspeed everyone is getting. I',m only getting about 70mph with a Rotax 912 ULS woodcomp prop at about 5400 rpm's. Is this normal or is my airspeed indicator off? Haven't had a chance to check it yet. 2) With slow flight and apporach to landing something clatters and bangs back in the fuselge, presumably oil canning. Normal? I checked everything else and nothing is loose. 3) Yesterday my engine faltered under full throttle and climb out and immediately got better when throttled back. On my Dynon monitor a Low Fuel Pressure warning popped up and it showed only about 1.9 to 2 psi, yet fuel flow was 5 gallons per hour. I returned home and checked the fuel flow and there is plenty of unobstructed flow as far as the front of the firewall anyway. I have a gascolater in front of the firewall that I'll check and clean today. The fuel pressure and fuel flow senders spliced into the line shouldn't obstruct the flow. On the ground at idle it is about 3 - 3.5 psi. Any ideas? It seems to run itself out of gas past about 5400rpm!?! 4) I was just getting used to the pitch sensitivity of the elevator and recieved the VG's from JG (in only a week! Send them via SST or SR-71?) Put them on the elevator and wow!! Almost too much sensitivity! It throws itself into the air and I found I have to be ready for it. Still in the learning curve of flying it, so haven't really done much testing of things yet. Mainly getting it up and down comfortably at this point. ________________________________ Message 19 ____________________________________ Time: 01:35:40 PM PST US From: Dan Wilde Subject: Re: Zenith701801-List: After 5 hours flight time, questions BokKat wrote: > 1) Just wondering what kind of indicated airspeed everyone is > getting. I',m only getting about 70mph with a Rotax 912 ULS woodcomp > prop at about 5400 rpm's. Is this normal or is my airspeed indicator > off? Haven't had a chance to check it yet. > 2) With slow flight and apporach to landing something clatters and > bangs back in the fuselge, presumably oil canning. Normal? I checked > everything else and nothing is loose. > 3) Yesterday my engine faltered under full throttle and climb out and > immediately got better when throttled back. On my Dynon monitor a Low > Fuel Pressure warning popped up and it showed only about 1.9 to 2 psi, > yet fuel flow was 5 gallons per hour. I returned home and checked the > fuel flow and there is plenty of unobstructed flow as far as the front > of the firewall anyway. I have a gascolater in front of the firewall > that I'll check and clean today. The fuel pressure and fuel flow > senders spliced into the line shouldn't obstruct the flow. On the > ground at idle it is about 3 - 3.5 psi. Any ideas? It seems to run > itself out of gas past about 5400rpm!?! > 4) I was just getting used to the pitch sensitivity of the elevator > and recieved the VG's from JG (in only a week! Send them via SST or > SR-71?) Put them on the elevator and wow!! Almost too much > sensitivity! It throws itself into the air and I found I have to be > ready for it. > Still in the learning curve of flying it, so haven't really done much > testing of things yet. Mainly getting it up and down comfortably at > this point. > * > > * 1) I am getting 80 mph at 4700 rpm with 912S and three bladed Warp Drive prop at 12 degrees pitch in straight and level flight. 2) I do not get a clatter but I do get a rumble at all speeds. 3) I have not had any faltering of the engine at any time even though my water temps have been running on the high side of normal. 4) The VG's are helpful. The are worth the cost. Dan Wilde N948DW ________________________________ Message 20 ____________________________________ Time: 02:10:45 PM PST US From: "Curt Thompson" Subject: RE: Zenith701801-List: fuel flow for CH701 Lots of great info Bob. Thanks for describing your test. If I put a vent line between the tanks, can that line dip and have a low spot? What if fuel sloshed up into that line? Let's say the dip was 3.3 inches and it filled with fuel. Seems to me that there would have to be a 3.3 inches of fuel head pressure (0.1 psi) differential between the tanks before the air would vent between the tanks. Is there a way to route that line between the tanks without any dips or is there a way to keep fuel out? Curt CH701, plans building. _____ From: owner-zenith701801-list-server@matronics.com [mailto:owner-zenith701801-list-server@matronics.com] On Behalf Of bob Sent: Wednesday, September 17, 2008 12:43 PM Subject: Zenith701801-List: fuel flow for CH701 Study of the Zenith CH701 two tank fuel system, Bob Kissell, N701UB ________________________________ Message 21 ____________________________________ Time: 02:17:05 PM PST US From: "Craig Payne" Subject: RE: Zenith701801-List: After 5 hours flight time, questions With the Woodcomp 3 bladed composite prop where and how are people measuring the pitch angle? I have the Woodcomp prop and a Warp Drive protractor. -- Craig ________________________________ Message 22 ____________________________________ Time: 02:50:33 PM PST US From: LarryMcFarland Subject: Re: Zenith701801-List: After 5 hours flight time, questions You should put the Warp Drive Protractor at the very tip of the blade, Craig. Larry McFarland 601HDS at www.macsmachine.com Craig Payne wrote: > *With the Woodcomp 3 bladed composite prop where and how are people measuring the pitch angle? I have the Woodcomp prop and a Warp Drive protractor.* > * * > *-- Craig* > * * > * > > * ________________________________ Message 23 ____________________________________ Time: 02:57:01 PM PST US From: Stanley Challgren Subject: Re: Zenith701801-List: FW: Zenith Gathering Mark/George: I just put my Olfa knife in my car. See you on Friday about noon. Stan On Sep 17, 2008, at 10:06 , George Race wrote: > > > > Can someone please help Mark out? > George > > -----Original Message----- > From: zodierocket@hsfx.ca [mailto:zodierocket@hsfx.ca] > Sent: Wednesday, September 17, 2008 9:19 AM > To: mykitairplane@mrrace.com > Subject: Zenith Gathering > > Hi George, could you do me a favor please. I came down to the open > house > early and forgot to bring a Olfa P-800 Knife for my Forum on Friday. > Could > you ask the lists if there is anyone who is attending on Friday if > they can > bring me a knife, used or new would be fine. I am trying to find one > locally, but don't expect to much success finding one here in Mexico, > Missouri. > > Thanks > > Mark Townsend > Can-Zac Aviation. > > ________________________________ Message 24 ____________________________________ Time: 04:33:07 PM PST US From: "Gordon" Subject: Re: Zenith701801-List: After 5 hours flight time, questions Good point Gary. If the Dynon (in Bokkat's case) was not set up properly with the ball centered when the plane is level he could be loosing a lot of speed by pushing the plane along sideways. G ----- Original Message ----- From: Gary Gower To: zenith701801-list@matronics.com Sent: Wednesday, September 17, 2008 3:53 PM Subject: Re: Zenith701801-List: After 5 hours flight time, questions Probably other 701 pilots have noticed this: Keep the oil canning, is a cheap and "automatic" built in Stall and Slip "alarm" in the 701, is a free bonus from ZAC no other airplane has that makes it extra safe.... Try to keep the ball centered always when flying and the low speed betwen 50 and 60 mph (with or without 15=B0 of flaps) when doing your approach and the "alarm" will not sound. When I flair to land I can lower the speed a lot more, but I have not noticed any alarm, probably I am too focused in my landing to hear it. :-) Also I have noticed that keeping the ball centered I have an extra Bonus: About more than 5 mph increase in cruise speed over the "alarm" speed... ;-) As my Instructor told me always in my student hours: "keep the ball centered" also a favorite from him was: I want 60, NOT 59 or 61 only 60" If I had recieve my instruction in the 701 he might only say: "Keep that oil canning off" :-) :-) Just my personal experience. About the post also, I have my pitch set for 87 mph at 5,000 rpm cruise (normally over 6,500 + ft ASL) moved the pitch a little at a time until got it set, cant remember the final degress of pitch, but was a little (like a milimeter) at a time. . Saludos Gary Gower Flying from Chapala, Mexico 701 912S 200 + hrs. Building a 601 XL Jab 3300. "Hope will also have the "alarm" built in..." --- On Wed, 9/17/08, BokKat wrote: From: BokKat Subject: Re: Zenith701801-List: After 5 hours flight time, questions To: zenith701801-list@matronics.com Date: Wednesday, September 17, 2008, 12:02 PM Wow, you must have your prop adjusted pretty coarse. Mine's probably too far the other way. I checked and was able to oil can the back of the baggage compartment and also the belly hatch. Maybe an L angle stiffener added here will "can" the noise! Thanks for the suggestions. ----- Original Message ----- From: Gordon To: zenith701801-list@matronics.com Sent: Wednesday, September 17, 2008 8:25 AM Subject: Re: Zenith701801-List: After 5 hours flight time, questions I have the same engine and prop and cruise at 4400 rpm (nice and quiet and low fuel burn) and show about 78mph + or minus depending on gross weight, turbulence and if I'm paying attention. This is on my Dynon and conventional ASI, both are within a MPH of each other. I get the same clatter in slow flight. In my case it's the back of the baggage compartment that starts oil canning and banging at about 50mph. Can't comment on the fuel issues -- I haven't had any. Gordon ----- Original Message ----- From: BokKat To: zenith701801-list@matronics.com Sent: Wednesday, September 17, 2008 8:34 AM Subject: Zenith701801-List: After 5 hours flight time, questions 1) Just wondering what kind of indicated airspeed everyone is getting. I',m only getting about 70mph with a Rotax 912 ULS woodcomp prop at about 5400 rpm's. Is this normal or is my airspeed indicator off? Haven't had a chance to check it yet. 2) With slow flight and apporach to landing something clatters and bangs back in the fuselge, presumably oil canning. Normal? I checked everything else and nothing is loose. 3) Yesterday my engine faltered under full throttle and climb out and immediately got better when throttled back. On my Dynon monitor a Low Fuel Pressure warning popped up and it showed only about 1.9 to 2 psi, yet fuel flow was 5 gallons per hour. I returned home and checked the fuel flow and there is plenty of unobstructed flow as far as the front of the firewall anyway. I have a gascolater in front of the firewall that I'll check and clean today. The fuel pressure and fuel flow senders spliced into the line shouldn't obstruct the flow. On the ground at idle it is about 3 - 3.5 psi. Any ideas? It seems to run itself out of gas past about 5400rpm!?! 4) I was just getting used to the pitch sensitivity of the elevator and recieved the VG's from JG (in only a week! Send them via SST or SR-71?) Put them on the elevator and wow!! Almost too much sensitivity! It throws itself into the air and I found I have to be ready for it. Still in the learning curve of flying it, so haven't really done much testing of things yet. Mainly getting it up and down comfortably at this point. href="http://www.matronics.com/Navigator?Zenith701801-List">http://www. matronics.com/Navigator?Zenith701801-List href="http://forums.matronics.com">http://forums.matronics.com href="http://www.matronics.com/contribution">http://www.matronics.com/c href="http://www.matronics.com/Navigator?Zenith701801-List">http://www. matronics.com/Navigator?Zenith701801-List href="http://forums.matronics.com">http://forums.matronics.com href="http://www.matronics.com/contribution">http://www.matronics.com/c ist" target=_blank rel=nofollow>http://www.matronics.com/Navigator?Zenith701801-List =nofollow>http://forums.matronics.com blank rel=nofollow>http://www.matronics.com/contribution ________________________________ Message 25 ____________________________________ Time: 06:08:40 PM PST US From: "Ken Ryan" Subject: Re: Zenith701801-List: fuel flow for CH701 X-mailer: Pegasus Mail for Windows (4.41) Let's say each fuel cap is vented to the outside air. Wouldn't that be the same as tieing them together with a vent line? What would make tying them together with a vent line better than just having two vented fuel caps? On 17 Sep 2008 at 15:42, bob wrote: > The best way to minimize the pressure difference is to have a common vent line that connects the two tanks together above the fuel level. ________________________________ Message 26 ____________________________________ Time: 06:22:48 PM PST US From: NYTerminat@aol.com Subject: Re: Zenith701801-List: After 5 hours flight time, questions 2" in from the tip of the prop. I used the line between the red tips and the black prop. Bob Spudis In a message dated 9/17/2008 5:17:52 P.M. Eastern Daylight Time, craig@craigandjean.com writes: With the Woodcomp 3 bladed composite prop where and how are people measuring the pitch angle? I have the Woodcomp prop and a Warp Drive protractor. -- Craig **************Psssst...Have you heard the news? There's a new fashion blog, plus the latest fall trends and hair styles at StyleList.com. (http://www.stylelist.com/trends?ncid=aolsty00050000000014) ________________________________ Message 27 ____________________________________ Time: 06:31:00 PM PST US From: "Craig Payne" Subject: RE: Zenith701801-List: After 5 hours flight time, questions Thanks, any advice on an initial angle? -- Craig From: owner-zenith701801-list-server@matronics.com [mailto:owner-zenith701801-list-server@matronics.com] On Behalf Of NYTerminat@aol.com Sent: Wednesday, September 17, 2008 7:23 PM Subject: Re: Zenith701801-List: After 5 hours flight time, questions 2" in from the tip of the prop. I used the line between the red tips and the black prop. Bob Spudis In a message dated 9/17/2008 5:17:52 P.M. Eastern Daylight Time, craig@craigandjean.com writes: With the Woodcomp 3 bladed composite prop where and how are people measuring the pitch angle? I have the Woodcomp prop and a Warp Drive protractor. -- Craig _____ Psssst...Have you heard the news? There's a new fashion blog, plus the latest fall trends and hair styles at StyleList.com. ________________________________ Message 28 ____________________________________ Time: 06:49:52 PM PST US From: "Curt Thompson" Subject: RE: Zenith701801-List: fuel flow for CH701 I think what some have said is that there is a little negative pressure (vacuum) at the vent in the cap. And then the vacuum is not the same on both sides. Attaching a tube to each cap and facing them forward causes a positive pressure. But again, this is not equal on both sides. Curt -----Original Message----- From: owner-zenith701801-list-server@matronics.com [mailto:owner-zenith701801-list-server@matronics.com] On Behalf Of Ken Ryan Sent: Wednesday, September 17, 2008 6:08 PM Subject: Re: Zenith701801-List: fuel flow for CH701 Let's say each fuel cap is vented to the outside air. Wouldn't that be the same as tieing them together with a vent line? What would make tying them together with a vent line better than just having two vented fuel caps? On 17 Sep 2008 at 15:42, bob wrote: > The best way to minimize the pressure difference is to have a common vent line that connects the two tanks together above the fuel level. ________________________________ Message 29 ____________________________________ Time: 06:53:37 PM PST US From: "n801bh@netzero.com" Subject: Re: Zenith701801-List: Re: fuel flow for CH701 My 801 does the same thing. I have both tanks tied together with a vent line and still the left tank will drain twice as fast as the right one.. My guess it has to do with the airflow swirling around the fuselage and wings,,,, coming off the prop in a circular motion. The right wing gets hit on the top and the left wing gets hit on the bottom.... Anyone got any other ideas ???? Ben Haas N801BH www.haaspowerair.com -- "n85ae" wrote: Great post, and a good experiment! That's exactly what my experience with my Kitfox has been as well. It's easy to discount the effects of the vents, and the vent plumbing but it is a very real phenomenon. Have ground tested my fuel flow from both tanks and they are very close, but in flight is a different matter. Even in carefully coordinated flight I get uneven flow. I think there's one 801 crashed when fuel flow stopped, which makes me very suspicious of the stock caps as the culprit. Jeff Read this topic online here: http://forums.matronics.com/viewtopic.php?p 4826#204826 ======================== =========== ======================== =========== ======================== =========== ======================== =========== ____________________________________________________________ Click to get information on owning your own franchise. Great products. Low entry cost. http://thirdpartyoffers.netzero.net/TGL2241/fc/Ioyw6i4vFkRvzLB1yCe4ahiVi TzCadosqsXsVIgQXvzGvwuuKSnLkO/ ________________________________ Message 30 ____________________________________ Time: 07:01:07 PM PST US From: "n801bh@netzero.com" Subject: Re: Zenith701801-List: fuel flow for CH701 I started with the Zenith supplied vent caps. The 801 has such a massive amount of lift the low pressure area above the wing will suck out fuel through the vented caps if I have anything more then 7/8 full tanks of f uel. One my first flight it stained the top of the right wing, yeah, I used Dupont Imron aircraft paint @ 300.00 + a gallon too. Boy, was I pis sed and I even stopped at the Dupont booth at Osk and explained my probl em. Those guys said , " yup, 100LL blue dye will stain the paint". So mu ch for aircraft grade crap !!! I epoxied up my caps and that fixed that issue. I also have aux vents that protrude below the wings with the fro nt of those tubes cut at an angle. Ben Haas N801BH www.haaspowerair.com -- "Ken Ryan" wrote: Let's say each fuel cap is vented to the outside air. Wouldn't that be t he same as tieing them together with a vent line? What would make tying the m together with a vent line better than just having two vented fuel caps? On 17 Sep 2008 at 15:42, bob wrote: > The best way to minimize the pressure difference is to have a common v ent line that connects the two tanks together above the fuel level. ======================== =========== ======================== =========== ======================== =========== ======================== =========== ____________________________________________________________ Planning for retirement? Click for free information on 401(k) plans. http://thirdpartyoffers.netzero.net/TGL2241/fc/Ioyw6i4tFiz4AoJzxobbaYH2b O0BUjTrVR6Xj2hVYPSDSlQuDrfB6y/ ________________________________ Message 31 ____________________________________ Time: 07:17:04 PM PST US From: NYTerminat@aol.com Subject: Re: Zenith701801-List: After 5 hours flight time, questions The Woodcomp manual says 11- 12 degrees, I ended up at a little over 13 degrees. I would start at 13 and see what your static RPM is. You should be at least 5400 static. Bob In a message dated 9/17/2008 9:31:25 P.M. Eastern Daylight Time, craig@craigandjean.com writes: Thanks, any advice on an initial angle? -- Craig From: owner-zenith701801-list-server@matronics.com [mailto:owner-zenith701801-list-server@matronics.com] On Behalf Of NYTerminat@aol.com Sent: Wednesday, September 17, 2008 7:23 PM Subject: Re: Zenith701801-List: After 5 hours flight time, questions 2" in from the tip of the prop. I used the line between the red tips and the black prop. Bob Spudis **************Psssst...Have you heard the news? There's a new fashion blog, plus the latest fall trends and hair styles at StyleList.com. (http://www.stylelist.com/trends?ncid=aolsty00050000000014) ________________________________ Message 32 ____________________________________ Time: 07:54:26 PM PST US Subject: Zenith701801-List: 801 wing root rib From: "bcchurch" I'm working on the right wing and ran into a problem with the root rib. When I locate the root rib, the rear spar deflects rearward 6 or 7 mm. The distance between the main spar and rear spar at all of the rear wing ribs is 820 mm. At the root rib, I get 827 mm. Now, the IB bottom skin is 820 mm wide which tells me that all the ribs are looking good except for the root rib. I'm discussing the issue with Caleb but wanted to ask some of the 801 builders here a few questions: 1) is the root rib parallel to the other rear wing ribs? 2) is the root rib the same length as the other rear wing ribs? 3) does the root rib join the rear spar at the 1st or 2nd row of pre-drilled holes in the rear spar? (My pre-drilled skin tells me the first row in the rear spar is correct). Without your parts in front of you, I realize it's a pretty small detail and probably hard to answer. I've attached an excel file with some measurements and notes to help describe my problem. I suppose there are some that would say I'm nit-picking over a few mm. But, when I get that root rib in place I really see a curve in the rear spar between the root and station 1 and I just don't like that. Thanks, Ben -------- Ben Church CH801 Racine, WI Read this topic online here: http://forums.matronics.com/viewtopic.php?p 4883#204883 Attachments: http://forums.matronics.com//files/wing_177.xls ------------------------------------------------------------------------------------- Other Matronics Email List Services ------------------------------------------------------------------------------------- Post A New Message zenith701801-list@matronics.com UN/SUBSCRIBE http://www.matronics.com/subscription List FAQ http://www.matronics.com/FAQ/Zenith701801-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/zenith701801-list Browse Digests http://www.matronics.com/digest/zenith701801-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.