---------------------------------------------------------- Zenith-List Digest Archive --- Total Messages Posted Fri 10/24/03: 12 ---------------------------------------------------------- Today's Message Index: ---------------------- 1. 03:57 AM - ZODIAC XL Wing removal (hugo van ruyskensvelde) 2. 05:56 AM - Re: Crash 701 (jnbolding1) 3. 06:05 AM - Re: Crash 701 (Benford2@aol.com) 4. 06:37 AM - Throttle Springs (Dave Alberti) 5. 07:53 AM - Re: Crash 701 (jnbolding1) 6. 08:02 AM - Re: Crash 701 (Flydog1966@aol.com) 7. 08:33 AM - Re: Crash 701 (Steve Dixon) 8. 11:41 AM - Re: Crash 701 (Larry McFarland) 9. 11:56 AM - Re: ZODIAC XL Wing removal (bryanmmartin@comcast.net) 10. 04:24 PM - Re: Crash 701 (caspainhower@aep.com) 11. 06:20 PM - Re: Crash 701 "going off topic?" (Gary Gower) 12. 07:43 PM - Re: Crash 701 (Greg Ferris) ________________________________ Message 1 _____________________________________ Time: 03:57:10 AM PST US From: hugo van ruyskensvelde Subject: Zenith-List: ZODIAC XL Wing removal --> Zenith-List message posted by: hugo van ruyskensvelde Hi, The website of ZAC states : "The wings bolt to the ZODIAC XL fuselage section, and can be easily removed for trailering or storing the aircraft." How long (minutes, hours ) does it take to connect the wings again to the fuselage ? Is it practical to trail your plane home every time you fly ? I live in Belgium and tie down places for airplanes are very costly. Thanks, hugo (searching for a practical airplane) ________________________________ Message 2 _____________________________________ Time: 05:56:40 AM PST US From: "jnbolding1" Subject: RE: Zenith-List: Crash 701 --> Zenith-List message posted by: "jnbolding1" It is unclear to me that >a broken push-pull wire is more likely than a broken spring, however. >It has worked now for 400+ hours. If memory serves (it does at an ever decreasing rate these days) NASCAR requires TWO springs to return the throttle to closed position in the event of actuator breakage /malfunction. Something else to think about huh? LOW&SLOW John ________________________________ Message 3 _____________________________________ Time: 06:05:14 AM PST US From: Benford2@aol.com Subject: Re: Zenith-List: Crash 701 --> Zenith-List message posted by: Benford2@aol.com In a message dated 10/24/2003 6:57:41 AM Mountain Daylight Time, jnbolding1@mail.ev1.net writes: > > If memory serves (it does at an ever decreasing rate these days) NASCAR > requires TWO springs to return the throttle to closed position in the event of > actuator breakage /malfunction. Something else to think about huh? LOW&SLOW > John > > This is exactly the opposite idea for safety. A hung full throttle has killed Adam Petty and others in racing. Full throttle in a plane is you friend when the linkage breaks. Ben Haas.N801BH. ________________________________ Message 4 _____________________________________ Time: 06:37:46 AM PST US From: "Dave Alberti" Subject: Zenith-List: Throttle Springs --> Zenith-List message posted by: "Dave Alberti" Carbs in the racing/NASCAR configuration will suck the throttle plates to wide open configuration with the loss of the return springs. The Rotax configuration is designed to assist even the added drag of linkage and cables in the event that the pilot is unable to control the throttle from the cockpit. This is exactly what happened to Jon's plane, but the replacement springs were too weak. I think the Zenith design would be safer still if the friction device were located in the cockpit and not on the firewall. That way any separation of the linkage past that friction point would easily be overcome by the springs. It is unclear to me that >a broken push-pull wire is more likely than a broken spring, however. >It has worked now for 400+ hours. If memory serves (it does at an ever decreasing rate these days) NASCAR requires TWO springs to return the throttle to closed position in the event of actuator breakage /malfunction. Something else to think about huh? LOW&SLOW John ________________________________ Message 5 _____________________________________ Time: 07:53:33 AM PST US From: "jnbolding1" Subject: Re: Zenith-List: Crash 701 --> Zenith-List message posted by: "jnbolding1" ---------- Original Message ---------------------------------- From: Benford2@aol.com >--> Zenith-List message posted by: Benford2@aol.com > >In a message dated 10/24/2003 6:57:41 AM Mountain Daylight Time, >jnbolding1@mail.ev1.net writes: > > >> >> If memory serves (it does at an ever decreasing rate these days) NASCAR >> requires TWO springs to return the throttle to closed position in the event of >> actuator breakage /malfunction. Something else to think about huh? LOW&SLOW >> John >> >> >This is exactly the opposite idea for safety. A hung full throttle has killed >Adam Petty and others in racing. Full throttle in a plane is you friend when >the linkage breaks. > >Ben Haas.N801BH. Was not suggesting that springs be rigged to CLOSE the throttle, only that TWO springs were required instead of one. I have always used throttle quadrants or knobs that were adjustable for friction from inside the cockpit. Never had two carbs thou and understand that compounds the problem. John ________________________________ Message 6 _____________________________________ Time: 08:02:26 AM PST US From: Flydog1966@aol.com Subject: Re: Zenith-List: Crash 701 --> Zenith-List message posted by: Flydog1966@aol.com In a message dated 10/23/03 6:08:47 PM Eastern Daylight Time, Jon@joncroke.com writes: << Actually, it is not accurate to say that it descended into the trees. I was about 10' off the runway when I applied full power from my go-around and got 4000 rpm or less; then JUST crossed above the power lines at about 25' ; then couldnt quite make it to about 50' when the trees arrived in my path. >> Ahh-haa, more clear now. I just had concearns like..."what kind of plane am I building, if it wo'nt fly with the power a Rotax 912 makes at 4000rpm." I looked on the Koiak/Rotax web site and found some interesting numbers: power setting % 65 75 100 rpm 4,800 5,000 5,800 hp 50 58 81 fuel consumption 4.2 5.1 6.3 no figure @ 4,000 rpm, but is interesting to see the significant power increase in the LAST 800 rpm. Yet the fuel consumption increases nearly linear. Takes fuel to make h.p. ,no? Any way, best-o-luck on the next. Phil do not archive ________________________________ Message 7 _____________________________________ Time: 08:33:14 AM PST US From: "Steve Dixon" Subject: Re: Zenith-List: Crash 701 --> Zenith-List message posted by: "Steve Dixon" That would be......redundancy! This would get my vote every time it could be used in a critical application. I was very sorry to hear about Jon's accident and the damage to his 701. At the same time, I was very happy to hear that he came out unscathed, and with an attitude that I thoroughly admire. I have enjoyed reading his posts from first flight to the mishap and beyond. He was doing exactly the kind of flying I plan to do in the future, so all his posts were very relevant to me. Thanks Jon, for all the information you have shared. Steve Dixon DO NOT ARCHIVE ----- Original Message ----- From: Subject: Re: Zenith-List: Crash 701 > --> Zenith-List message posted by: Benford2@aol.com > > In a message dated 10/24/2003 6:57:41 AM Mountain Daylight Time, > jnbolding1@mail.ev1.net writes: > > > > > > If memory serves (it does at an ever decreasing rate these days) NASCAR > > requires TWO springs to return the throttle to closed position in the event of > > actuator breakage /malfunction. Something else to think about huh? LOW&SLOW > > John > > > > > This is exactly the opposite idea for safety. A hung full throttle has killed > Adam Petty and others in racing. Full throttle in a plane is you friend when > the linkage breaks. > > Ben Haas.N801BH. > > ________________________________ Message 8 _____________________________________ Time: 11:41:31 AM PST US From: "Larry McFarland" Subject: Re: Zenith-List: Crash 701 --> Zenith-List message posted by: "Larry McFarland" "Full throttle in a plane is you friend when the linkage breaks." Seems there's a difference of opinion as to whether the spring and cables are an advantaged design or source of a problem. This design seems to have only succeeded in making a 2-carb connection linkage. Most aircraft throttles are free of springs that preclude failure when done correctly. A design that offers full throttle at the occasion of a broken cable begins a defective argument for its use. The throttle should only do what the pilot intends it to do a the time it is needed without breakage or secondary consequences. It would be frightening if all the aircraft at Oshkosh employed a full open spring throttle at startup and taxiing, etc. I doubt that commercial aircraft standards would tolerate such a design for certification. If it's possible to use a solid throttle linkage, it should be carefully considered. Larry McFarland @ www.macsmachine.com ________________________________ Message 9 _____________________________________ Time: 11:56:58 AM PST US From: bryanmmartin@comcast.net Subject: Re: Zenith-List: ZODIAC XL Wing removal --> Zenith-List message posted by: bryanmmartin@comcast.net > --> Zenith-List message posted by: hugo van ruyskensvelde > >How long (minutes, hours ) does it take to connect the wings again to the > fuselage ? > Is it practical to trail your plane home every time you fly ? On each wing of the 601XL there are six bolts through the spar and one bolt through the rear Z that hold the wing on. You have to remove an access panel under the seat cushion to get at the bolts in the spar. Since the fuel in the standard kit is contained in the wings, there are also fuel lines to disconnect to remove the wings. There may also be electrical and pitot-static lines to disconnect. As a guess I would say that two people could remove the wings in half an hour or so if the kit is built with quick disconnects for the fluid and electrical lines. It would not be an easy job for one person to do alone. If you plan on removing the wings frequently, I think you would be better off putting in a header tank in the forward fuselage instaid of the wing tanks. This would simplfy the wing removal process. If you build the kit with ease of wing removal in mind, it should be quite practical to trailer the plane to the airport each time you fly. Bryan Martin CH 601XL ________________________________ Message 10 ____________________________________ Time: 04:24:19 PM PST US Subject: Re: Zenith-List: Crash 701 From: caspainhower@aep.com 10/24/2003 07:23:29 PM --> Zenith-List message posted by: caspainhower@aep.com > If memory serves (it does at an ever decreasing rate these days) NASCAR > requires TWO springs to return the throttle to closed position in the event of > actuator breakage /malfunction. Something else to think about huh? LOW&SLOW > John > > >This is exactly the opposite idea for safety. A hung full throttle has killed >Adam Petty and others in racing. Full throttle in a plane is you friend when >the linkage breaks. I may be way off here, but I think the point is; if it's critical to safety you may want to have TWO springs in case the first one fails. Craig S. 601 XL fuel tanks plumbed and left wing almost ready to close. This e-mail message and all attachments transmitted with it from the Nuclear Generation Group of American Electric Power are for the sole use of the intended recipient(s) and may contain confidential and privileged information. Any unauthorized review, use, disclosure or distribution is prohibited. If you are not the intended recipient, please contact the sender by reply e-mail and destroy all copies of the original message. ________________________________ Message 11 ____________________________________ Time: 06:20:38 PM PST US From: Gary Gower Subject: Re: Zenith-List: Crash 701 "going off topic?" --> Zenith-List message posted by: Gary Gower Friends: I think We are getting "off topic" with this theme, the ascelerator system in Jon plane did not failed, remember the the problem was not the failure of the system, but something very normal that Jon thought was a good idea (we also thought of it as probably most of you have), He replaced the hard springs with some too light to work properly... When you pull the thottle with the friction stop and the original springs... Is hard! This is a fact, but we can live with it. I personaly dont think the cables will fail in the life of the engine (1000+hrs), but if we (as pilots) are in doubt, we can change them in the annual or "X" amount of hours (say 100, 200, 500...), they are very easy to visual check every oil /plugs change, I doubt that there is any sign of cables or spring wear in the older engines in this list (say 500+ hrs) Any Facts from the Ol' experienced in 912 pilots?. We will probably use the original springs in our planes, but since Jon incident we made some tests in our engine while we install the instruments... (sometimes we have to do something :-) We tryed with the VW carb springs, are the same size but just a little less hard, we also put special attention in the "curves" of the cables betwen the carbs and the firewall, to be as gentle as possible, also we used the liquid rubber for grips and handles (I saw the can is sold by Permatex). Is flexible but very hard when cured, will not break, and hold the end of the cables "balls" to the bolt very well... We have pushed very fast (this will not be done in flight to prevent engine "cof" of course) and the cables moved freely, all this with the engine stoped (not even has the prop installed) is only in the engine mount waiting for the cowling. Just my point of view. and remeber this (I like them a lot): "If its not broken dont fix it" and "Only Add simplicity and lightness to an airplane" also "One very dificult goal is to design something as simple as possible". Hope this helps Saludos Gary Gower. --- caspainhower@aep.com wrote: > --> Zenith-List message posted by: caspainhower@aep.com > > > > If memory serves (it does at an ever decreasing rate these days) > NASCAR > > requires TWO springs to return the throttle to closed position in > the > event of > > actuator breakage /malfunction. Something else to think about huh? > LOW&SLOW > > John > > > > > > >This is exactly the opposite idea for safety. A hung full throttle > has > killed > >Adam Petty and others in racing. Full throttle in a plane is you > friend > when > >the linkage breaks. > > I may be way off here, but I think the point is; if it's critical to > safety > you may want to have TWO springs in case the first one fails. > > Craig S. > 601 XL fuel tanks plumbed and left wing almost ready to close. > > > This e-mail message and all attachments transmitted with it from the > Nuclear Generation Group of American Electric Power are for the sole > use of the intended recipient(s) and may contain confidential and > privileged information. Any unauthorized review, use, disclosure or > distribution is prohibited. If you are not the intended recipient, > please > contact the sender by reply e-mail and destroy all copies of the > original > message. > > > > > > > > __________________________________ ________________________________ Message 12 ____________________________________ Time: 07:43:49 PM PST US From: "Greg Ferris" Subject: Re: Zenith-List: Crash 701 --> Zenith-List message posted by: "Greg Ferris" In cars, a torsion spring closes the throttle. As a safety measure, 2 springs are simultaneously coiled to offer redundency (they are tack welded at each end). One thing to consider is the deflection of these springs and the wire size. The deflection and wire size produce very low loading of the springs which will give them a very long fatigue life. It would be a good idea to change them when the engine is overhauled, but with all of the testing and field hours on the engine, I don't worry about it. If you use 2 springs, each one will have to be half the force unless you want to have to pry at the throttle lever. If one of those breaks, then you may have the same issue that caused this incident. Greg ----- Original Message ----- From: Subject: Re: Zenith-List: Crash 701 > --> Zenith-List message posted by: caspainhower@aep.com > > > > If memory serves (it does at an ever decreasing rate these days) NASCAR > > requires TWO springs to return the throttle to closed position in the > event of > > actuator breakage /malfunction. Something else to think about huh? > LOW&SLOW > > John > > > > > > >This is exactly the opposite idea for safety. A hung full throttle has > killed > >Adam Petty and others in racing. Full throttle in a plane is you friend > when > >the linkage breaks. > > I may be way off here, but I think the point is; if it's critical to safety > you may want to have TWO springs in case the first one fails. > > Craig S. > 601 XL fuel tanks plumbed and left wing almost ready to close. > > > This e-mail message and all attachments transmitted with it from the > Nuclear Generation Group of American Electric Power are for the sole > use of the intended recipient(s) and may contain confidential and > privileged information. Any unauthorized review, use, disclosure or > distribution is prohibited. If you are not the intended recipient, please > contact the sender by reply e-mail and destroy all copies of the original > message. > >