---------------------------------------------------------- Pietenpol-List Digest Archive --- Total Messages Posted Tue 02/04/03: 20 ---------------------------------------------------------- Today's Message Index: ---------------------- 1. 05:17 AM - wire wheels for sale (rambog@erols.com) 2. 07:50 AM - Re: Landing Gear Placement (John Dilatush) 3. 08:02 AM - Re: Landing Gear Placement (Waytogopiet@aol.com) 4. 09:17 AM - Re: Question about Gross Weight (Jon Botsford) 5. 10:12 AM - some sources on gear position (Christian Bobka) 6. 12:38 PM - Re: Question about Gross Weight (walter evans) 7. 02:16 PM - Re: some sources on gear position (Borodent@aol.com) 8. 04:59 PM - Re: long fuse gear (D.Dale Johnson) 9. 05:02 PM - my feeelings on dihedral (Christian Bobka) 10. 05:31 PM - Re: long fuse gear (walter evans) 11. 05:32 PM - Re: my feeelings on dihedral (DJ Vegh) 12. 06:18 PM - Re: Question about Gross Weight (Jack Phillips) 13. 08:43 PM - Re: fuel gauges (Christian Bobka) 14. 08:54 PM - Re: Question about Gross Weight (Mike) 15. 08:57 PM - I discoverd something (Christian Bobka) 16. 09:09 PM - Re: I discoverd something (DJ Vegh) 17. 09:23 PM - Re: I discoverd something (TWINBOOM) 18. 09:30 PM - Re: I discoverd something (Christian Bobka) 19. 09:37 PM - Re: I discoverd something (Christian Bobka) 20. 09:55 PM - Re: I discoverd something (DJ Vegh) ________________________________ Message 1 _____________________________________ Time: 05:17:35 AM PST US From: "rambog@erols.com" Subject: Pietenpol-List: wire wheels for sale --> Pietenpol-List message posted by: "rambog@erols.com" I am selling a pair of wire wheels I had intended to put on my Piet. These are an original pair of wheels from the early 1920's. They are size 24x4 which is called for in some of the Piet plans. Some Jennies came with this same wheel, but these are not clinchers, they are drop-center. Of course, they do not have brakes. These are the same wheels that are on the Golden Age Air Museum's model A Piet in Pennsylvania, and you can see a photo on their web site. 24x4 means that the wheel is 16" in diameter and the tire is 4" tall, for a total of 24". The axle size is 1 1/2, correct size for the Piet. When I bought the wheels, I disassembled them while I was working at the Air & Space facility at Silver Hill. We soaked them in several chemical baths to remove all rust and coat the metal. I primed them with chromated black paint and clear coated over that. The wheels had some surface rust which has left the surface with a "textured" look from light surface pitting, but they are not damaged or weakened. I had planned to cover them with fabric anyway. I ordered all new spokes from Buchanan's and trued the wheels. It was everyone's opinion that these wheels have never been mounted on an airplane due to the lack of wear marks on the bronze bushings. I have quite a bit invested in the wheels, but if someone really wants them I am willing to negotiate. I have found anopther pair of wire wheels that are a different size and I like better. Anyone that is interested please e-mail me and let me know what you would give for these. Gene ________________________________ Message 2 _____________________________________ Time: 07:50:53 AM PST US From: "John Dilatush" Subject: Re: Pietenpol-List: Landing Gear Placement --> Pietenpol-List message posted by: "John Dilatush" ----- Original Message ----- From: Subject: Re: Pietenpol-List: Landing Gear Placement +++++++++++++++++++ Dennis, That measurement is 12 degrees, which is a line drawn from the calculated center of gravity of the entire plane swung forward of vertical 12 degrees to the point of ground contact of the wheel. This measurement depends on the usage of plane and can vary from about 10.5 to as much as 20 degrees. At the minimum of 10.5 degrees, you would find on a plane that doesn't have brakes and a low CG. At the other end of the scale you might have a design such as a Helio Courier with a high CG and used for short fields and heavy braking. David Thurston in his book "Design for Flying" suggests 16.5 degrees as the average for a certified aircraft. However remember that the further forward the gear is, the greater tendency to ground looping and the harder it is to raise the tail on take off. I used 12 degrees arbitrarily and have found it perfect for a Pietenpol. Hope this helps, John D. +++++++++++++++++++++++++ > --> Pietenpol-List message posted by: Dmott9@aol.com > > In a message dated 2/3/03 7:18:52 AM Eastern Standard Time, > dilatush@amigo.net writes: > > > When it came to the placement of the gear, I figured that I wanted to have > > the ground contact of the wheels to be about 12 degrees forward of the CG. > > Turned out to be perfect. I can use the brakes pretty hard without any > > tendency to nose over, (the brakes are not that effective)yet it is light > > enough on the tailwheel, (12 lbs) to handle easily on the ground. > > I am curious John, how did you arrive at the 12 degrees forward of the CG ? > Or is that 12 inches ? > -dennis > > ________________________________ Message 3 _____________________________________ Time: 08:02:01 AM PST US From: Waytogopiet@aol.com Subject: Re: Pietenpol-List: Landing Gear Placement --> Pietenpol-List message posted by: Waytogopiet@aol.com Dave, I would be very interested in seeing this if you are able to scan and post. Don Hicks ________________________________ Message 4 _____________________________________ Time: 09:17:54 AM PST US From: "Jon Botsford" Subject: Re: Pietenpol-List: Question about Gross Weight --> Pietenpol-List message posted by: "Jon Botsford" To all, Thanks for you insight on gross weight. It is very helpful. jon b ----- Original Message ----- From: "clif" Subject: Re: Pietenpol-List: Question about Gross Weight > --> Pietenpol-List message posted by: clif > > I have a formula for " minimum safe horsepower" > around here somewhere. I believe it's based on > the minimum hp that will provide a climb of 300 ft/min. > The ford A hp comes out right at that figure. So > my assumption has been that the power available > was the original bases for Bernards choice of gross > weight. Now that we have more powerful engines > in use the gross wt can be optimized for other > parameters, with safety in mind, of course. As Jack > has pointed out we must be carefull in our assumptions. > > One question is how come the new plans come with > a 3/4" spar when the original was 1"? Who determined > that this is safe? Who performed the necessary > calculations? Where can we see these and what > design load was used? What are the permissable > G loads with this spar? > > The answers are important to us now that we have > overcome the original power limitations. > Clif. > ----- Original Message ----- > From: "Jack Phillips" > To: > Subject: RE: Pietenpol-List: Question about Gross Weight > > > > --> Pietenpol-List message posted by: "Jack Phillips" > > > > > Jon, > > > > Chris is right, up to a point. The gross weight is basically set by some > > structural parameter in the aircraft, usually the wing spar or the landing > > gear. You hear of a plane being stressed to +/- 10 G's, well that means > > the structure can handle a certain limit load, and depending on how many > G's > > the designer wants the plane to be good for, he divides the limit load by > > that number of G's and voila - the gross weight pops out! > > > > When I was a young engineer just out of college and was working for > General > > Dynamics on the F-16 initial design (sad that a plane designed in 1975 is > > still one of our front line fighters), the initial gross weight of the > plane > > was 23,000 lbs. (which meant it could go supersonic straight up with its > > 25,000 lb. thrust engine). Later, some mods to the landing gear enabled > it > > to takeoff with more fuel on board in external tanks and the takeoff gross > > weight was increased to 37,000 lbs, but its maneuvering gross weight was > > still 23,000. > > > > In other words, the gross weight is somewhat arbitrary. However, be aware > > that stall speed is a variable and goes up with gross weight. It is quite > > possible with a robust structured airplane to have a gross weight that is > > structurally safe but simply can't fly because the stall speed is too > high. > > > > For my Pietenpol, I've figured on a gross weight of around 1100 lbs. > > > > Jack > > > > -----Original Message----- > > From: owner-pietenpol-list-server@matronics.com > > [mailto:owner-pietenpol-list-server@matronics.com] On Behalf Of Christian > > Bobka > > Sent: Sunday, February 02, 2003 11:36 PM > > To: pietenpol-list@matronics.com > > Subject: RE: Pietenpol-List: Question about Gross Weight > > > > --> Pietenpol-List message posted by: "Christian Bobka" > > > > > Jon, > > > > For an experimental, it is whatever you want it to be. Believe it or not. > > You set the rules. No kidding. > > > > Chris Bobka > > > > -----Original Message----- > > From: owner-pietenpol-list-server@matronics.com > > [mailto:owner-pietenpol-list-server@matronics.com]On Behalf Of Jon > > Botsford > > To: pietenpol-list@matronics.com > > Subject: Pietenpol-List: Question about Gross Weight > > > > > > --> Pietenpol-List message posted by: "Jon Botsford" > > > > > Can someone on this list tell me how the Gross Weight is calculated for an > > aircraft? > > > > Jon Botsford > > > > > > ________________________________ Message 5 _____________________________________ Time: 10:12:32 AM PST US From: "Christian Bobka" Subject: Pietenpol-List: some sources on gear position --> Pietenpol-List message posted by: "Christian Bobka" I did some research in my extensive aeronautical library and have turned up the following: Source: Aircraft Design Vol II Aero Structures by Cecil Hugh Latimer-Needham published 1939 says: "The point of wheel contact with the ground [not the axle centerline] should make an angle with the vertical through the CG in side elevation (aircraft rigging position) of not less than 10 degrees, and may increase with wheel brakes up to a maximum of 14 degrees. The tendency of aircraft to overturn when landing with wheel brakes may be provided against by arranging for the brakes to be released as the tail skid leaves the ground. It has been found, however, that if the angle, made by the line joining the point of wheel contact [not the axle centerline] to the CG with the vertical through the CG when the tail skid is touching, is at least 20 degrees no overturning is likely. An angle much greater than 20 degrees results in excessive tail loads at landing and difficulty in taxi-ing and at takeoff. It may be noted that the overturning tendency is not great at the moment of touching down, since the aircraft is still largely airborne and skidding of the wheels takes place. Towards the end of the run both aerodynamic lift and control are negligible, the braking effect increases and for safety the braking laod should be decreased." Latimer-Needham is an Englishman. rigging position refers to tail elevated so that upper longereons on the piet are level. Source: Prelimiary Aircraft Design by R. C. Wilson published 1941 says, in the context of drawing a side elevation with the tail in rigging position, as defined above: "E. Location of the Landing Gear (Main Wheels and Tail Wheel System) From the assumed CG draw a line downward and forward making the vertical an angle of not more than 20 degrees nor less than 12 degrees. The former angle should be used when extremely effective brakes are to be used, the latter when no wheel brakes whatever are contemplated. A fair normal figure for ordinary wheels and brakes is 18 degrees. The axle of the main wheels [not the point of wheel contact with the ground], with shock absorbers fully compressed, will lie on this diagonal line." Wilson is from the U.S. I added the comments in the [ ] for emphasis. Note that the Brits define the diagonal line as that from the CG through THE WHEEL POINT OF CONTACT WITH THE GROUND. The Americans define the diagonal as that from the CG through THE AXLE CENTERLINE. The diameter of the wheel, therfore, comes into play in the British scenario. I hope this helps. Chris Bobka ________________________________ Message 6 _____________________________________ Time: 12:38:29 PM PST US From: "walter evans" Subject: Re: Pietenpol-List: Question about Gross Weight --> Pietenpol-List message posted by: "walter evans" Clif, I've often wondered those things too. But just to add....... was in a hanger and saw an Aeronca (don't know which model) wing with the fabric ripped off. It's amazing to see, the wing had 3/4" wood spars. They look like a skinny piece of book shelf. Since then I've pulled some "G's" in one doing steep turns. That memory always pops in my head at those times. walt ----- Original Message ----- From: "clif" Subject: Re: Pietenpol-List: Question about Gross Weight > --> Pietenpol-List message posted by: clif > <<>> >> One question is how come the new plans come with > a 3/4" spar when the original was 1"? Who determined > that this is safe? Who performed the necessary > calculations? Where can we see these and what > design load was used? What are the permissable > G loads with this spar? > > The answers are important to us now that we have > overcome the original power limitations. > Clif. > ----- Original Message ----- > From: "Jack Phillips" > To: > Subject: RE: Pietenpol-List: Question about Gross Weight > > > > --> Pietenpol-List message posted by: "Jack Phillips" > > > > > Jon, > > > > Chris is right, up to a point. The gross weight is basically set by some > > structural parameter in the aircraft, usually the wing spar or the landing > > gear. You hear of a plane being stressed to +/- 10 G's, well that means > > the structure can handle a certain limit load, and depending on how many > G's > > the designer wants the plane to be good for, he divides the limit load by > > that number of G's and voila - the gross weight pops out! > > > > When I was a young engineer just out of college and was working for > General > > Dynamics on the F-16 initial design (sad that a plane designed in 1975 is > > still one of our front line fighters), the initial gross weight of the > plane > > was 23,000 lbs. (which meant it could go supersonic straight up with its > > 25,000 lb. thrust engine). Later, some mods to the landing gear enabled > it > > to takeoff with more fuel on board in external tanks and the takeoff gross > > weight was increased to 37,000 lbs, but its maneuvering gross weight was > > still 23,000. > > > > In other words, the gross weight is somewhat arbitrary. However, be aware > > that stall speed is a variable and goes up with gross weight. It is quite > > possible with a robust structured airplane to have a gross weight that is > > structurally safe but simply can't fly because the stall speed is too > high. > > > > For my Pietenpol, I've figured on a gross weight of around 1100 lbs. > > > > Jack > > > > -----Original Message----- > > From: owner-pietenpol-list-server@matronics.com > > [mailto:owner-pietenpol-list-server@matronics.com] On Behalf Of Christian > > Bobka > > Sent: Sunday, February 02, 2003 11:36 PM > > To: pietenpol-list@matronics.com > > Subject: RE: Pietenpol-List: Question about Gross Weight > > > > --> Pietenpol-List message posted by: "Christian Bobka" > > > > > Jon, > > > > For an experimental, it is whatever you want it to be. Believe it or not. > > You set the rules. No kidding. > > > > Chris Bobka > > > > -----Original Message----- > > From: owner-pietenpol-list-server@matronics.com > > [mailto:owner-pietenpol-list-server@matronics.com]On Behalf Of Jon > > Botsford > > To: pietenpol-list@matronics.com > > Subject: Pietenpol-List: Question about Gross Weight > > > > > > --> Pietenpol-List message posted by: "Jon Botsford" > > > > > Can someone on this list tell me how the Gross Weight is calculated for an > > aircraft? > > > > Jon Botsford > > > > > > ________________________________ Message 7 _____________________________________ Time: 02:16:20 PM PST US From: Borodent@aol.com Subject: Re: Pietenpol-List: some sources on gear position --> Pietenpol-List message posted by: Borodent@aol.com Chris does aircraft rigging position refer to the plane positioned- tail up - as if it were flying in straight and level? Henry Williams trying to decide on dihedral: yes or no ________________________________ Message 8 _____________________________________ Time: 04:59:24 PM PST US Subject: Re: Pietenpol-List: long fuse gear From: "D.Dale Johnson" --> Pietenpol-List message posted by: "D.Dale Johnson" Dick N Not ready for W/B yet. Have the wings covered but not the fuselage Moved the wing back 3 " Moved the engine forward 1.5 " Put on a heavy prop. I hope we are close. Dale ________________________________ Message 9 _____________________________________ Time: 05:02:31 PM PST US From: "Christian Bobka" Subject: Pietenpol-List: my feeelings on dihedral --> Pietenpol-List message posted by: "Christian Bobka" From: Christian Bobka Subject: Re: dihedral Why mess with the dihedral. Every aircraft has apparent dihedral (what you see) and effective dihedral (what you get). Successful aircraft designs without dihedral or anhedral or negative dihedral have enough effective dihedral to provide the stability required. Such things as a slab sided fuselage (like the Piet or a Taylorcraft, for example) create a lot of effective dihedral. Some airplanes like the C-141 Starlifter and the Avro BAE 146/RJ-85 had so much effective dihedral early in their design phase that a lot of negative dihedral was necessary to get the aircraft's stability in a desirable range. In a side slip/gust upset, air gets dammed up under the wing and against the fuselage and provides way too much corrective action so the negative dihedral is used to correct this characteristic. So the bottom line is why change something that ain't broke. Did not Bernard do all the tinkering for us and found the right combination? Just think. In a correctly designed aircraft, if a vertical gust upsets the left wing, lifting it up, the aircraft sideslips a little to the right, creating a little more lift on the right side, bringing the right wing up THE SAME AMOUNT as the left wing went up initially. SO....a little rudder action on your part to keep it heading the way you were going and the plane flies sweet. Add a little dihedral, THAT IS NOT NEEDED, and the scenario goes like this. A vertical gust upsets the left wing, lifting it up, and the aircraft sideslips a little to the right. But there is too much effective dihedral, so a little more lift is created on the right side during the sideslip and it is more than what is needed to right the aircraft. So the right wing goes up a little more than the left wing did initially. This has the same effect of having a gust upset from the right. Now the aircraft sideslips a little to the left.... And there you go, round and round. A miserable airplane to fly because it has too much stability. As an exercise, think about what would happen if you did not have enough effective dihedral. Read old issues of Kitplanes where Barnaby Wainfan discusses dihedral effect. Or read Perkins and Hage's Aircraft Stability and Control. Or read Aerodynamics for Naval Aviators. If you still don't get it, then pull out your trusty copy of Langewiesche's Stick and Rudder. It is all there. Leave it alone. ________________________________ Message 10 ____________________________________ Time: 05:31:25 PM PST US From: "walter evans" Subject: Re: Pietenpol-List: long fuse gear --> Pietenpol-List message posted by: "walter evans" Dale, In a nutshell it sounds like my Piet. My WB came in at the rear CG with my 200+ arse. I built to plans for the long fuselage. You shouldn't have any probs. walt ----- Original Message ----- From: "D.Dale Johnson" Subject: Re: Pietenpol-List: long fuse gear > --> Pietenpol-List message posted by: "D.Dale Johnson" > > Dick N > Not ready for W/B yet. > Have the wings covered but not the fuselage > Moved the wing back 3 " > Moved the engine forward 1.5 " > Put on a heavy prop. > I hope we are close. > Dale > > ________________________________ Message 11 ____________________________________ Time: 05:32:39 PM PST US From: "DJ Vegh" Subject: Re: Pietenpol-List: my feeelings on dihedral --> Pietenpol-List message posted by: "DJ Vegh" the only reason I'm adding a tad of dihedral is to kill the "drooping wing" visual effect of a straight winged Piet. DJ Vegh N74DV www.raptoronline.com Mesa, AZ ----- Original Message ----- From: "Christian Bobka" Subject: Pietenpol-List: my feeelings on dihedral > --> Pietenpol-List message posted by: "Christian Bobka" > > Date: Dec 31, 2000 > From: Christian Bobka > Subject: Re: dihedral > > Why mess with the dihedral. Every aircraft has apparent dihedral (what you > see) and effective dihedral (what you get). Successful aircraft designs > without dihedral or anhedral or negative dihedral have enough effective > dihedral to provide the stability required. Such things as a slab sided > fuselage (like the Piet or a Taylorcraft, for example) create a lot of > effective dihedral. Some airplanes like the C-141 Starlifter and the Avro > BAE 146/RJ-85 had so much effective dihedral early in their design phase > that a lot of negative dihedral was necessary to get the aircraft's > stability in a desirable range. In a side slip/gust upset, air gets dammed > up under the wing and against the fuselage and provides way too much > corrective action so the negative dihedral is used to correct this > characteristic. > > So the bottom line is why change something that ain't broke. Did not > Bernard do all the tinkering for us and found the right combination? > > Just think. In a correctly designed aircraft, if a vertical gust upsets the > left wing, lifting it up, the aircraft sideslips a little to the right, > creating a little more lift on the right side, bringing the right wing up > THE SAME AMOUNT as the left wing went up initially. SO....a little rudder > action on your part to keep it heading the way you were going and the plane > flies sweet. Add a little dihedral, THAT IS NOT NEEDED, and the scenario > goes like this. A vertical gust upsets the left wing, lifting it up, and > the aircraft sideslips a little to the right. But there is too much > effective dihedral, so a little more lift is created on the right side > during the sideslip and it is more than what is needed to right the > aircraft. So the right wing goes up a little more than the left wing did > initially. This has the same effect of having a gust upset from the right. > Now the aircraft sideslips a little to the left.... And there you go, > round and round. A miserable airplane to fly because it has too much > stability. > > As an exercise, think about what would happen if you did not have enough > effective dihedral. > > Read old issues of Kitplanes where Barnaby Wainfan discusses dihedral > effect. Or read Perkins and Hage's Aircraft Stability and Control. Or > read Aerodynamics for Naval Aviators. If you still don't get it, then pull > out your trusty copy of Langewiesche's Stick and Rudder. It is all there. > > Leave it alone. > > This email has been scanned for known viruses and made safe for viewing by Half Price Hosting, a leading email and web hosting provider. For more information on an anti-virus email solution, visit . ________________________________ Message 12 ____________________________________ Time: 06:18:05 PM PST US From: "Jack Phillips" Subject: RE: Pietenpol-List: Question about Gross Weight --> Pietenpol-List message posted by: "Jack Phillips" Citabrias also have 3/4" spars, as do Pitts Specials and many other aerobatic planes. 1" is overkill, which is why BHP routed them down. I used 3/4" spars fore and aft in my Piet. Jack -----Original Message----- From: owner-pietenpol-list-server@matronics.com [mailto:owner-pietenpol-list-server@matronics.com] On Behalf Of walter evans Subject: Re: Pietenpol-List: Question about Gross Weight --> Pietenpol-List message posted by: "walter evans" Clif, I've often wondered those things too. But just to add....... was in a hanger and saw an Aeronca (don't know which model) wing with the fabric ripped off. It's amazing to see, the wing had 3/4" wood spars. They look like a skinny piece of book shelf. Since then I've pulled some "G's" in one doing steep turns. That memory always pops in my head at those times. walt ----- Original Message ----- From: "clif" Subject: Re: Pietenpol-List: Question about Gross Weight > --> Pietenpol-List message posted by: clif > <<>> >> One question is how come the new plans come with > a 3/4" spar when the original was 1"? Who determined > that this is safe? Who performed the necessary > calculations? Where can we see these and what > design load was used? What are the permissable > G loads with this spar? > > The answers are important to us now that we have > overcome the original power limitations. > Clif. > ----- Original Message ----- > From: "Jack Phillips" > To: > Subject: RE: Pietenpol-List: Question about Gross Weight > > > > --> Pietenpol-List message posted by: "Jack Phillips" > > > > > Jon, > > > > Chris is right, up to a point. The gross weight is basically set by some > > structural parameter in the aircraft, usually the wing spar or the landing > > gear. You hear of a plane being stressed to +/- 10 G's, well that means > > the structure can handle a certain limit load, and depending on how many > G's > > the designer wants the plane to be good for, he divides the limit load by > > that number of G's and voila - the gross weight pops out! > > > > When I was a young engineer just out of college and was working for > General > > Dynamics on the F-16 initial design (sad that a plane designed in 1975 is > > still one of our front line fighters), the initial gross weight of the > plane > > was 23,000 lbs. (which meant it could go supersonic straight up with its > > 25,000 lb. thrust engine). Later, some mods to the landing gear enabled > it > > to takeoff with more fuel on board in external tanks and the takeoff gross > > weight was increased to 37,000 lbs, but its maneuvering gross weight was > > still 23,000. > > > > In other words, the gross weight is somewhat arbitrary. However, be aware > > that stall speed is a variable and goes up with gross weight. It is quite > > possible with a robust structured airplane to have a gross weight that is > > structurally safe but simply can't fly because the stall speed is too > high. > > > > For my Pietenpol, I've figured on a gross weight of around 1100 lbs. > > > > Jack > > > > -----Original Message----- > > From: owner-pietenpol-list-server@matronics.com > > [mailto:owner-pietenpol-list-server@matronics.com] On Behalf Of Christian > > Bobka > > Sent: Sunday, February 02, 2003 11:36 PM > > To: pietenpol-list@matronics.com > > Subject: RE: Pietenpol-List: Question about Gross Weight > > > > --> Pietenpol-List message posted by: "Christian Bobka" > > > > > Jon, > > > > For an experimental, it is whatever you want it to be. Believe it or not. > > You set the rules. No kidding. > > > > Chris Bobka > > > > -----Original Message----- > > From: owner-pietenpol-list-server@matronics.com > > [mailto:owner-pietenpol-list-server@matronics.com]On Behalf Of Jon > > Botsford > > To: pietenpol-list@matronics.com > > Subject: Pietenpol-List: Question about Gross Weight > > > > > > --> Pietenpol-List message posted by: "Jon Botsford" > > > > > Can someone on this list tell me how the Gross Weight is calculated for an > > aircraft? > > > > Jon Botsford > > > > > > ________________________________ Message 13 ____________________________________ Time: 08:43:23 PM PST US From: "Christian Bobka" "pietenpol" Subject: Pietenpol-List: RE: fuel gauges --> Pietenpol-List message posted by: "Christian Bobka" Eddie, Follow these rules: The tank in the fusealge is the main tank. The tank in the wing is and auxialry tank. The fuselage tank must be no closer than 1/2 inch to the firewall. Both tanks must be vented and vented in such a manner is to prevent ice formation on the vent (even in florida). Both tanks must have a sump and sump drain at their lowest point in a parked attitude. Air must be able to circulate around the tanks somehow and fumes and liquid fuel must be able to escape down and out from the space beneath the tanks. The fuel for engine use will not be drawn from the main tank at the sump but at some point higher than the sump. Test pressure is 3-1/2 psi for the tanks. And what you asked for: "Where two or more tanks are interconnected and it is impossible to feed from each one separately, only one fuel-level gauge need be installed." Obviously the gauge is for the main tank only as the aux tank will drain into the main tank. Copper fuel lines must be annealed after they are bent. Ed, I hope this helps. chris -----Original Message----- From: Ed Grentzer [mailto:flyboy_120@hotmail.com] Subject: fuel gauges Hi Chris...How's it going...good luck with your D.A.R. application..We definitely need more qualitied D.A.R.s out there. I have a technical question..I'm building a 7.5 gallon wing tank for the forward 15" of my center section. Behind the tank will be a small baggage compartment. I'm trying to keep the cg forward as much as I can so this tank is centered above the most fwd/rearward recommended cg measurements. The function of the wing tank will just be to replenish the cowl tank during flight. I think Walt Evans has a similar set up but with a full sized wing tank. Anyhoo..I read somewhere that "each fuel tank must have a fuel quantity gauge" My question is if a tank is only used to refill a tank which has a gauge does that tank ( the wing tank) have to have a gauge?? My tank mold is finished but if I HAVE TO install a gauge now would be the time to add the sender boss to the mold. Thanks in advance. Ed G. ________________________________ Message 14 ____________________________________ Time: 08:54:24 PM PST US From: Mike Subject: Re: Pietenpol-List: Question about Gross Weight --> Pietenpol-List message posted by: Mike Bernie routed down the center portions of his spars to save weight but didn't rout the spar caps. The material in the center of a beam (spar) in bending does very little other than carry shear loads. This is why there are many spars with the "beef" located at the top and bottom with only a plywood shear web between the caps. A much more important measurement than the spar thickness is the spar's width, from top to bottom. Before we go writing off Bernie's spars as overkill on thickness, lets do a real comparison with these other famously strong wings that includes spar width, length of the wing in actual bending (the Piet wing inboard of the strut attach points sees less bending load than the outboard portion), comparable flight loads, etc. A blanket statement that 1" is overkill because something like a Pitts has thinner spars is not really supportable. The experiences of a very large number of builders who have successfully and safely flown 3/4" spars is certainly more reliable than comparing apples and oranges, but I'm not sure anyone has any idea how much safety margin is left over when pulling significant flight loads on spars thinner than designed. Mike Jack Phillips wrote: > --> Pietenpol-List message posted by: "Jack Phillips" > > Citabrias also have 3/4" spars, as do Pitts Specials and many other > aerobatic planes. 1" is overkill, which is why BHP routed them down. I > used 3/4" spars fore and aft in my Piet. > > Jack ________________________________ Message 15 ____________________________________ Time: 08:57:20 PM PST US From: "Christian Bobka" Subject: Pietenpol-List: I discoverd something --> Pietenpol-List message posted by: "Christian Bobka" While researching dihedral I learned that the word meaning "negative dihedral" is the word "cathedral". I never could remember whether a cathode was negative or positive. Now I will remember a Cathode is negative... chris bobka ________________________________ Message 16 ____________________________________ Time: 09:09:34 PM PST US From: "DJ Vegh" Subject: Re: Pietenpol-List: I discoverd something --> Pietenpol-List message posted by: "DJ Vegh" hmmm I've always known it as "anhedral" DJ Vegh N74DV www.raptoronline.com Mesa, AZ ----- Original Message ----- From: "Christian Bobka" Subject: Pietenpol-List: I discoverd something > --> Pietenpol-List message posted by: "Christian Bobka" > > While researching dihedral I learned that the word meaning "negative > dihedral" is the word "cathedral". I never could remember whether a cathode > was negative or positive. Now I will remember a Cathode is negative... > > chris bobka > This email has been scanned for known viruses and made safe for viewing by Half Price Hosting, a leading email and web hosting provider. For more information on an anti-virus email solution, visit . ________________________________ Message 17 ____________________________________ Time: 09:23:55 PM PST US From: "TWINBOOM" Subject: Re: Pietenpol-List: I discoverd something --> Pietenpol-List message posted by: "TWINBOOM" Chris, In the R/C soaring group I run with, they call negative dihedral, "annhedral", ever hear that one? Doug Blackburn Doug/Elizabeth Blackburn Yucaipa California Inland Slope Rebels, Riverside Ca. http://inlandsloperebels.com ----- Original Message ----- From: "Christian Bobka" Subject: Pietenpol-List: I discoverd something > --> Pietenpol-List message posted by: "Christian Bobka" > > While researching dihedral I learned that the word meaning "negative > dihedral" is the word "cathedral". I never could remember whether a cathode > was negative or positive. Now I will remember a Cathode is negative... > > chris bobka > > ________________________________ Message 18 ____________________________________ Time: 09:30:47 PM PST US From: "Christian Bobka" Subject: RE: Pietenpol-List: I discoverd something --> Pietenpol-List message posted by: "Christian Bobka" DJ, The prefixes A or AN mean "without" so anhedral is no dihedral and no cathedral. Atheist meaning without God and anonymous meaning without name. Chris Bobka -----Original Message----- From: owner-pietenpol-list-server@matronics.com [mailto:owner-pietenpol-list-server@matronics.com]On Behalf Of DJ Vegh Subject: Re: Pietenpol-List: I discoverd something --> Pietenpol-List message posted by: "DJ Vegh" hmmm I've always known it as "anhedral" DJ Vegh N74DV www.raptoronline.com Mesa, AZ ----- Original Message ----- From: "Christian Bobka" Subject: Pietenpol-List: I discoverd something > --> Pietenpol-List message posted by: "Christian Bobka" > > While researching dihedral I learned that the word meaning "negative > dihedral" is the word "cathedral". I never could remember whether a cathode > was negative or positive. Now I will remember a Cathode is negative... > > chris bobka > This email has been scanned for known viruses and made safe for viewing by Half Price Hosting, a leading email and web hosting provider. For more information on an anti-virus email solution, visit . ________________________________ Message 19 ____________________________________ Time: 09:37:10 PM PST US From: "Christian Bobka" Subject: RE: Pietenpol-List: I discoverd something --> Pietenpol-List message posted by: "Christian Bobka" Doug, I think words take on meanings of their own, despite their Latin roots. My references are books from the 'thirties. chris -----Original Message----- From: owner-pietenpol-list-server@matronics.com [mailto:owner-pietenpol-list-server@matronics.com]On Behalf Of TWINBOOM Subject: Re: Pietenpol-List: I discoverd something --> Pietenpol-List message posted by: "TWINBOOM" Chris, In the R/C soaring group I run with, they call negative dihedral, "annhedral", ever hear that one? Doug Blackburn Doug/Elizabeth Blackburn Yucaipa California Inland Slope Rebels, Riverside Ca. http://inlandsloperebels.com ----- Original Message ----- From: "Christian Bobka" Subject: Pietenpol-List: I discoverd something > --> Pietenpol-List message posted by: "Christian Bobka" > > While researching dihedral I learned that the word meaning "negative > dihedral" is the word "cathedral". I never could remember whether a cathode > was negative or positive. Now I will remember a Cathode is negative... > > chris bobka > > ________________________________ Message 20 ____________________________________ Time: 09:55:03 PM PST US From: "DJ Vegh" Subject: Re: Pietenpol-List: I discoverd something --> Pietenpol-List message posted by: "DJ Vegh" wow.... learn sumthin' new every day..... DJ Vegh N74DV www.raptoronline.com Mesa, AZ ----- Original Message ----- From: "Christian Bobka" Subject: RE: Pietenpol-List: I discoverd something > --> Pietenpol-List message posted by: "Christian Bobka" > > DJ, > > The prefixes A or AN mean "without" so anhedral is no dihedral and no > cathedral. Atheist meaning without God and anonymous meaning without name. > > Chris Bobka > This email has been scanned for known viruses and made safe for viewing by Half Price Hosting, a leading email and web hosting provider. For more information on an anti-virus email solution, visit .