---------------------------------------------------------- Kolb-List Digest Archive --- Total Messages Posted Wed 08/28/19: 6 ---------------------------------------------------------- Today's Message Index: ---------------------- 1. 07:33 AM - Re: FireFly Weight and Balance (Richard Girard) 2. 07:47 AM - Re: Re: FireFly Weight and Balance (Richard Girard) 3. 09:01 AM - Re: FireFly Weight and Balance (Denny Baber) 4. 09:49 AM - Re: FireFly Weight and Balance (John Hauck) 5. 03:17 PM - Re: Re: FireFly Weight and Balance (Terry) 6. 06:44 PM - Re: Re: FireFly Weight and Balance (Russ Kinne) ________________________________ Message 1 _____________________________________ Time: 07:33:54 AM PST US From: Richard Girard Subject: Re: Kolb-List: FireFly Weight and Balance Sid, Measure the chord of the FIrefly wing, include the aileron. Divide by 4. That's the quarter chord point measured from the leading edge. That is roughly the ideal CG. Divide your original chord measurement by 10. Add and subtract that number from the quarter chord point. That's your CG range from 15% to 35% chord. If you find your CG is a little aft, BUT by no means further than 40% chord, you're still OK, Kolbs tend to fly better with an aft CG. However, if you can move something forward to get into the 15 to 35% range, do that. Last, It is vitally important that you get the aircraft at the proper attitude for measuring the arms. Roughly, it's horizontal stabilizer level. Check with Kolb they may have an angle for the engine mount (about 3 degrees for the Mk III) or the underside of the wing (9 degrees on the Mk III). I know that the Kolb uses the the leading edge of the wing as the origin for calculating the CG. Do yourself a favor and use the nose of the aircraft instead. The reason is simple, no negative numbers in your calculations. If you keep the origin forward all calculations are additions (you could put the origin at the tail for that matter and all calculations would still be consistent and that's what you're after). Nothing can screw up a CG calculation faster than adding a moment arm when it should be subtracted. Hope this helps, Rick On Sat, Aug 24, 2019 at 1:06 PM sidsx wrote: > > Can anyone tell me if the CG limits for the FireFly are different from th e > FireStar > (12.8 to 22.4} I have a copy of the W&B for the FireStar not for the > FireFly. > Thanks, > > > Read this topic online here: > > http://forums.matronics.com/viewtopic.php?p=491026#491026 > > =========== =========== =========== =========== =========== > > -- =9CBlessed are the cracked, for they shall let in the light.=9D Groucho Marx ________________________________ Message 2 _____________________________________ Time: 07:47:36 AM PST US From: Richard Girard Subject: Re: Kolb-List: Re: FireFly Weight and Balance Eugene, That's about the worst advice I've ever seen on this forum. First, if the aircraft has any sort of experimental certificate, either ELSA or EAB, a weight and balance measurement is REQUIRED by law. It's a part of your aircraft's operating limitations. Second, Aft CG has probably been the cause or contributed to far too many stall spin accidents, or as the FAA calls it, Loss of Control. Just because it's an ultralight doesn't give the aircraft a pass on the physics of flight. Assuming an aircraft is in proper trim is like assuming the pistol is unloaded. There is one positive side to not doing a W & B, you'll probably qualify for next year's Darwin Awards. Rick On Sun, Aug 25, 2019 at 12:01 PM Eugene Zimmerman wrote: > > Concern about CG limits on any Kolb aircraft is for all practical purpose s > unnecessary unless there is a significant deviation from, or modification > of, the airframe from the original Kolb design plans. > > The best way to optimize the CG on any Kolb airplane is to test fly the > airplane and trim the control surfaces to fly hands off straight and > level. Modifying a Kolb aircraft's CG is beneficial only for the purpose s > of minimizing significant control surface deflection necessary for > neutral-hands off straight and level flight. > > > Read this topic online here: > > http://forums.matronics.com/viewtopic.php?p=491047#491047 > > =========== =========== =========== =========== =========== > > -- =9CBlessed are the cracked, for they shall let in the light.=9D Groucho Marx ________________________________ Message 3 _____________________________________ Time: 09:01:36 AM PST US From: Denny Baber Subject: Re: Kolb-List: FireFly Weight and Balance I agree with your observations on weight and balance. If you can get the center of gravity right below the center of lift you won't need any trim tabs. I also like to calculate it with an empty tank of gas so if that ever happens you can still fly it to the ground. Respectfully, Dennis Baber Cape Coral, Fl baberdk@gmail.com Stay Curious ________________________________ Message 4 _____________________________________ Time: 09:49:33 AM PST US From: John Hauck Subject: RE: Kolb-List: FireFly Weight and Balance SSBkaXNhZ3JlZSBvbiB5b3VyIHN0YXRlbWVudDogICJJZiB5b3UgY2FuIGdldCB0aGUgY2VudGVy IG9mIGdyYXZpdHkgcmlnaHQgYmVsb3cgdGhlIGNlbnRlciBvZiBsaWZ0IHlvdSB3b24ndCBuZWVk IGFueSB0cmltIHRhYnMuIg0KDQpJbiBvbmUgcmVzcGVjdCBpdCBpcyBwcm9iYWJseSB0cnVlLiAg VGhhdCBiZWluZyBmbHlpbmcgdGhlIEtvbGIgd2l0aG91dCBwb3dlci4gIEhvd2V2ZXIsIGFzIHNv b24gYXMgeW91IGJyaW5nIHRoZSBwb3dlciBpbiwgdGhlIGhpZ2ggdGhydXN0IGxpbmUgd2lsbCBw dXNoIHRoZSBub3NlIGRvd24gYW5kIGFmdCBzdGljayBwcmVzc3VyZSB3aWxsIGJlIHJlcXVpcmVk IHRvIGhvbGUgdGhlIGFpcmNyYWZ0IGxldmVsLCB1bmxlc3MgeW91IGhhdmUgZm9yY2VkIHBpdGNo IHRyaW0gb3IgYW4gZWxldmF0b3IgdHJpbSB0YWIuICBJdCBpcyB0aGUgbmF0dXJlIG9mIHRoZSBi ZWFzdC4NCg0KSSByZWNlbnRseSByZWxhdGVkIG15IGV4cGVyaWVuY2Ugd2l0aCBteSBNS0lJSS4g IE5vIHBpdGNoIHRyaW0sIG5vIHBvd2VyLCBwZXJmZWN0IGhhbmRzIG9mZiBmbGlnaHQuICBCcmlu ZyBpbiB0aGUgcG93ZXIgYW5kIGJyaW5nIGluIHRoZSBub3NlIHVwIGZvcmNlZCB0cmltLg0KDQpq b2huIGgNCm1rSUlJDQpUaXR1cywgQWxhYmFtYQ0KDQpGcm9tOiBvd25lci1rb2xiLWxpc3Qtc2Vy dmVyQG1hdHJvbmljcy5jb20gW21haWx0bzpvd25lci1rb2xiLWxpc3Qtc2VydmVyQG1hdHJvbmlj cy5jb21dIE9uIEJlaGFsZiBPZiBEZW5ueSBCYWJlcg0KU2VudDogV2VkbmVzZGF5LCBBdWd1c3Qg MjgsIDIwMTkgMTE6MDAgQU0NClRvOiBrb2xiLWxpc3RAbWF0cm9uaWNzLmNvbQ0KU3ViamVjdDog UmU6IEtvbGItTGlzdDogRmlyZUZseSBXZWlnaHQgYW5kIEJhbGFuY2UNCg0KSSBhZ3JlZSB3aXRo IHlvdXIgb2JzZXJ2YXRpb25zIG9uIHdlaWdodCBhbmQgYmFsYW5jZS4gSWYgeW91IGNhbiBnZXQg dGhlIGNlbnRlciBvZiBncmF2aXR5IHJpZ2h0IGJlbG93IHRoZSBjZW50ZXIgb2YgbGlmdCB5b3Ug d29uJ3QgbmVlZCBhbnkgdHJpbSB0YWJzLiBJIGFsc28gbGlrZSB0byBjYWxjdWxhdGUgaXQgd2l0 aCBhbiBlbXB0eSB0YW5rIG9mIGdhcyBzbyBpZiB0aGF0IGV2ZXIgaGFwcGVucyB5b3UgY2FuIHN0 aWxsIGZseSBpdCB0byB0aGUgZ3JvdW5kLg0KDQoNClJlc3BlY3RmdWxseSwNCkRlbm5pcyBCYWJl cg0KQ2FwZSBDb3JhbCwgRmwNCmJhYmVyZGtAZ21haWwuY29tPG1haWx0bzpiYWJlcmRrQGdtYWls LmNvbT4NCg0KDQpTdGF5IEN1cmlvdXMNCg0KDQo ________________________________ Message 5 _____________________________________ Time: 03:17:17 PM PST US Subject: Re: Kolb-List: Re: FireFly Weight and Balance From: Terry Rick, Who died and made you God?! This is why some of us went to ultralights so that we could get away from aviation Nazi's like you. You think you know it all, but have no idea how much time Eugene has in the air proving you wrong. I think he knows more about the physics of flight then you will ever understand. Maybe you could suggest you disagree without be an a-hole about it. Talk about a an entry into the Darwin awards. Grow up!! Terry On 8/28/2019 10:46 AM, Richard Girard wrote: > Eugene, That's about the worst advice I've ever seen on this forum. > First, if the aircraft has any sort of experimental certificate, > either ELSA or EAB, a weight and balance measurement is REQUIRED by > law. It's a part of your aircraft's operating limitations. > Second, Aft CG has probably been the cause or contributed to far too > many stall spin accidents, or as the FAA calls it, Loss of Control. > Just because it's an ultralight doesn't give the aircraft a pass on > the physics of flight. Assuming an aircraft is in proper trim is like > assuming the pistol is unloaded. > There is one positive side to not doing a W & B, you'll probably > qualify for next year's Darwin Awards. > > Rick > > On Sun, Aug 25, 2019 at 12:01 PM Eugene Zimmerman > wrote: > > > > > Concern about CG limits on any Kolb aircraft is for all practical > purposes unnecessary unless there is a significant deviation from, > or modification of, the airframe from the original Kolb design plans. > > The best way to optimize the CG on any Kolb airplane is to test > fly the airplane and trim the control surfaces to fly hands off > straight and level. Modifying a Kolb aircraft's CG is beneficial > only for the purposes of minimizing significant control surface > deflection necessary for neutral-hands off straight and level flight. > > > Read this topic online here: > > http://forums.matronics.com/viewtopic.php?p=491047#491047 > > > ========== > -List" rel="noreferrer" > target="_blank">http://www.matronics.com/Navigator?Kolb-List > ========== > FORUMS - > eferrer" target="_blank">http://forums.matronics.com > ========== > WIKI - > errer" target="_blank">http://wiki.matronics.com > ========== > b Site - > -Matt Dralle, List Admin. > rel="noreferrer" target="_blank">http://www.matronics.com/contribution > ========== > > > -- > > > Blessed are the cracked, for they shall let in the light. Groucho > Marx > > ________________________________ Message 6 _____________________________________ Time: 06:44:17 PM PST US From: Russ Kinne Subject: Re: Kolb-List: Re: FireFly Weight and Balance Terry: Grow Up! > On Aug 28, 2019, at 6:15 PM, Terry wrote: > > Rick, > > Who died and made you God?! This is why some of us went to ultralights so that we could get away from aviation Nazi's like you. You think you know it all, but have no idea how much time Eugene has in the air proving you wrong. I think he knows more about the physics of flight then you will ever understand. > > Maybe you could suggest you disagree without be an a-hole about it. Talk about a an entry into the Darwin awards. Grow up!! > > Terry > > > > On 8/28/2019 10:46 AM, Richard Girard wrote: >> Eugene, That's about the worst advice I've ever seen on this forum. >> First, if the aircraft has any sort of experimental certificate, either ELSA or EAB, a weight and balance measurement is REQUIRED by law. It's a part of your aircraft's operating limitations. >> Second, Aft CG has probably been the cause or contributed to far too many stall spin accidents, or as the FAA calls it, Loss of Control. >> Just because it's an ultralight doesn't give the aircraft a pass on the physics of flight. Assuming an aircraft is in proper trim is like assuming the pistol is unloaded. >> There is one positive side to not doing a W & B, you'll probably qualify for next year's Darwin Awards. >> >> Rick >> >> On Sun, Aug 25, 2019 at 12:01 PM Eugene Zimmerman > wrote: > >> >> Concern about CG limits on any Kolb aircraft is for all practical purposes unnecessary unless there is a significant deviation from, or modification of, the airframe from the original Kolb design plans. >> >> The best way to optimize the CG on any Kolb airplane is to test fly the airplane and trim the control surfaces to fly hands off straight and level. Modifying a Kolb aircraft's CG is beneficial only for the purposes of minimizing significant control surface deflection necessary for neutral-hands off straight and level flight. >> >> >> >> >> Read this topic online here: >> >> http://forums.matronics.com/viewtopic.php?p=491047#491047 >> >> >> >> >> >> >> ========== >> -List" rel="noreferrer" target="_blank">http://www.matronics.com/Navigator?Kolb-List >> ========== >> FORUMS - >> eferrer" target="_blank">http://forums.matronics.com >> ========== >> WIKI - >> errer" target="_blank">http://wiki.matronics.com >> ========== >> b Site - >> -Matt Dralle, List Admin. >> rel="noreferrer" target="_blank">http://www.matronics.com/contribution >> ========== >> >> >> >> >> >> -- >> =9CBlessed are the cracked, for they shall let in the light. =9D Groucho Marx >> ------------------------------------------------------------------------------------- Other Matronics Email List Services ------------------------------------------------------------------------------------- Post A New Message kolb-list@matronics.com UN/SUBSCRIBE http://www.matronics.com/subscription List FAQ http://www.matronics.com/FAQ/Kolb-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/kolb-list Browse Digests http://www.matronics.com/digest/kolb-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.