---------------------------------------------------------- Kolb-List Digest Archive --- Total Messages Posted Sun 04/17/11: 10 ---------------------------------------------------------- Today's Message Index: ---------------------- 1. 06:30 AM - Re: Re: 2nd Flight! (Richard Girard) 2. 07:45 AM - ramp checks (chris davis) 3. 09:33 AM - Re: ramp checks (b young) 4. 12:38 PM - Prop MOI (Jimmy Young) 5. 02:26 PM - Re: Prop MOI (Richard Girard) 6. 05:21 PM - Re: Prop MOI (Jimmy Young) 7. 05:39 PM - Re: Prop MOI (robert bean) 8. 08:22 PM - Re: Re: Prop MOI (Jack B. Hart) 9. 09:32 PM - Re: Prop MOI (DAquaNut@aol.com) 10. 10:01 PM - Re: Prop MOI (Richard Pike) ________________________________ Message 1 _____________________________________ Time: 06:30:20 AM PST US Subject: Re: Kolb-List: Re: 2nd Flight! From: Richard Girard Richard, Greg, Seems like a lot of work to get the weight down and still not qualify as an ultralight. Why? Speed. The Firestar cruises too fast. The limit under FAR 103 is 55 knots. Do the worksheet from AC 103-7 Appendix 1. Your local FAA guy might not have his scales, but he probably will have a pencil. Rick Girard On Sat, Apr 16, 2011 at 6:22 PM, Richard Pike wrote: > > [quote="gtaylor35918(at)roadrunne"]Kolbers, > I appreciate all the info, I have the plane down to roughly about > 288, with no BRS. The faa told me I basically had to options, use my > firestar to repair one that is currently registered, or get it down to 254 > LBS. My biggest worry with flying it as a fat ultralight is if they were to > ramp check me and find it overweight what my punishment would be, or how > would it affect my private/instrument rating. > > > --- > > > The way I see it, you need to strip the fabric off the airplane and take it > apart. Weigh the various pieces, and see what you can make go away. > Eliminate everything you can do without. Period. > > Until you get it down to 245 pounds, you need to keep at it. Then recover > it using U/L fabric and minimal paint. I suspect that if you came below 260 > pounds, you might be able to skate, but you need to get it very, very close. > Due to changes in humidity, etc, there are legitimate variables, but I would > aim for under 260 if I was concerned about making the scales. > > Richard Pike > MKIII N420P (420ldPoops) > > > Read this topic online here: > > http://forums.matronics.com/viewtopic.php?p=337161#337161 > > -- Zulu Delta Mk IIIC Thanks, Homer GBYM It isn't necessary to have relatives in Kansas City in order to be unhappy. - Groucho Marx ________________________________ Message 2 _____________________________________ Time: 07:45:10 AM PST US From: chris davis Subject: Kolb-List: ramp checks dont know where thesubject for my last post came from but my question was how many of us has ever been weighed or even questioned on a ramp check or even ever had a ramp check? Chris Davis KXP 503 492 hrs Glider Pilot Disabled from crash building Firefly ----- Original Message ---- From: chris davis Sent: Sat, April 16, 2011 8:25:19 PM Subject: Kolb-List: Que pachuca con toluca! Just my cuiorosity, but how many of us have ever been weighed on a ramp check? Had my Firestar sitting at the fuel pump at Chatham municipal when an FAA inspector walked by (gave me a heart attack) he said when talking to the electronics man setting up the automatic weather reporting unit"serious looking little aircraft" and thats as close as my KXP weighing 330lbs ever got go a ramp check! KXP 503 492 hrs Glider Pilot Disabled from crash building Firefly ----- Original Message ---- From: Richard Pike Sent: Sat, April 16, 2011 7:22:47 PM Subject: Kolb-List: Re: 2nd Flight! [quote="gtaylor35918(at)roadrunne"]Kolbers, I appreciate all the info, I have the plane down to roughly about 288, with no BRS. The faa told me I basically had to options, use my firestar to repair one that is currently registered, or get it down to 254 LBS. My biggest worry with flying it as a fat ultralight is if they were to ramp check me and find it overweight what my punishment would be, or how would it affect my private/instrument rating. > --- The way I see it, you need to strip the fabric off the airplane and take it apart. Weigh the various pieces, and see what you can make go away. Eliminate everything you can do without. Period. Until you get it down to 245 pounds, you need to keep at it. Then recover it using U/L fabric and minimal paint. I suspect that if you came below 260 pounds, you might be able to skate, but you need to get it very, very close. Due to changes in humidity, etc, there are legitimate variables, but I would aim for under 260 if I was concerned about making the scales. Richard Pike MKIII N420P (420ldPoops) Read this topic online here: http://forums.matronics.com/viewtopic.php?p=337161#337161 ________________________________ Message 3 _____________________________________ Time: 09:33:36 AM PST US From: "b young" Subject: Re: Kolb-List: ramp checks dont know where the subject for my last post came from but my question was how many of us has ever been weighed or even questioned on a ramp check or even ever had a ramp check? Chris Davis >>>>>>>>>>>>>>>>>>>>> i have heard of one,,,, 15 - 20 years ago my friend was ramp checked at Monument Valley.,,, faa inspector was on vacation,, and decided a working vacation was in order. probably could get the boss to pay for the hotel room that way. boyd young mkiii utah ________________________________ Message 4 _____________________________________ Time: 12:38:23 PM PST US Subject: Kolb-List: Prop MOI From: "Jimmy Young" I ran the Rotax Service Info propeller mass moment of inertia test today on both my Powerfin 66" 2-Blade & the Warp Drive 64" 3-Blade props. Here is what I found: Powerfin: weight, 3.03 kg seconds required for 30 occillations, 162 MOI, 2700 kgcm^ Warp Drive: weight, 4.09 kg seconds required for 30 occillations, 180 MOI, 4500 kgcm^ Since the max. MOI for the HKS "B" box is 3000 kgcm^, I've put the Powerfin back on for now. The Warp Drive was smoother & performed better in climb and cruise on the nice/still/calm Tuesday morning I tested it, about 100 - 150 fpm climb increase and incrementally better cruise of 2 mph. What I thought was most impressive about it was I could maintain altitude at 4400 rpm vs. 4700 rpm with the Powerfin. The only conclusion I can draw from that is the Warp must be a more efficient prop on my particular plane. Both props made the engine run very rough if the idle speed drops to less than 1800 rpm, but both were fine once rpm's go over 2000. From what I've learned, at low idle is where most of the conflict occurs. I've always had my HKS set to idle at about 2200 rpm once it's warmed up. What I'm looking for is a more durable prop, which is why I wanted to use a Warp Drive. I'd like to find out what a WD 2-Blade 66" prop's MOI is without having to buy one first. My guess would be it would slightly exceed the 3000 kg limit, but if it were just by a little bit I wouldn't be concerned. I haven't been flying all that long, so I'm not up to date about what many of the 503 "B" box powered Kolbs that have WD props are using. The 3000 kg MOI limit applies to them as well. Can any of you long-time veterans of our sport shed any light on that? -------- Jimmy Young Missouri City, TX Kolb FS II/HKS 700 Read this topic online here: http://forums.matronics.com/viewtopic.php?p=337239#337239 ________________________________ Message 5 _____________________________________ Time: 02:26:36 PM PST US Subject: Re: Kolb-List: Prop MOI From: Richard Girard Jimmy, You might consider having the WD's blades tapered and the stainless leading edge removed. Both will lower the MOI of the prop since you are removing mass where it has the most effect, out at the tips. Doing that should help considerably. Personally, I don't think many people do the MOI test, even though, as you've found out, it's pretty simple, and there's a lot of misinformation about it. One fellow I know believes that Warp Drive props have an MOI up around 10,000. How long have you run the WD? Have you gone a full oil change interval? If you didn't change out the oil drain plug for one with a magnet on it, run a magnet through your old oil at the next change. If the WD is causing problems iron on the magnet is your early warning signal. I have the 3.47 gearbox that has the higher MOI limit and I run a four blade Powerfin on my trike, but it still made a lot of metal during the first 50 hours until the gears were run in. Every oil change has been clean since then. There may be another benefit to having the blades tapered, too. One of our EAA chapter members works with Paul Lipps on the Ellipse props. He did a presentation on propeller design at our meeting last Friday night. One of his claims was that a propeller with a constant chord planform, like yours and mine, is like having a wing with wing tips eight times as wide, chordwise, as the wing root. I started planning on having my blades tapered right then. Rick Girard On Sun, Apr 17, 2011 at 2:35 PM, Jimmy Young wrote: > > I ran the Rotax Service Info propeller mass moment of inertia test today on > both my Powerfin 66" 2-Blade & the Warp Drive 64" 3-Blade props. Here is > what I found: > > Powerfin: weight, 3.03 kg > seconds required for 30 occillations, 162 > MOI, 2700 kgcm^ > > Warp Drive: weight, 4.09 kg > seconds required for 30 occillations, 180 > MOI, 4500 kgcm^ > > Since the max. MOI for the HKS "B" box is 3000 kgcm^, I've put the Powerfin > back on for now. The Warp Drive was smoother & performed better in climb and > cruise on the nice/still/calm Tuesday morning I tested it, about 100 - 150 > fpm climb increase and incrementally better cruise of 2 mph. What I thought > was most impressive about it was I could maintain altitude at 4400 rpm vs. > 4700 rpm with the Powerfin. The only conclusion I can draw from that is the > Warp must be a more efficient prop on my particular plane. > > Both props made the engine run very rough if the idle speed drops to less > than 1800 rpm, but both were fine once rpm's go over 2000. From what I've > learned, at low idle is where most of the conflict occurs. I've always had > my HKS set to idle at about 2200 rpm once it's warmed up. > > What I'm looking for is a more durable prop, which is why I wanted to use a > Warp Drive. I'd like to find out what a WD 2-Blade 66" prop's MOI is without > having to buy one first. My guess would be it would slightly exceed the > 3000 kg limit, but if it were just by a little bit I wouldn't be concerned. > > I haven't been flying all that long, so I'm not up to date about what many > of the 503 "B" box powered Kolbs that have WD props are using. The 3000 kg > MOI limit applies to them as well. Can any of you long-time veterans of our > sport shed any light on that? > > -------- > Jimmy Young > Missouri City, TX > Kolb FS II/HKS 700 > > > Read this topic online here: > > http://forums.matronics.com/viewtopic.php?p=337239#337239 > > -- Zulu Delta Mk IIIC Thanks, Homer GBYM It isn't necessary to have relatives in Kansas City in order to be unhappy. - Groucho Marx ________________________________ Message 6 _____________________________________ Time: 05:21:13 PM PST US Subject: Kolb-List: Re: Prop MOI From: "Jimmy Young" > You might consider having the WD's blades tapered and the stainless leading edge removed. Rick, I'll talk with WD tomorrow & see what suggestions they have. I should have done my research before I bought the prop, so it is on me. Maybe tapering the blades could solve the problem, since an 8.25 lb., 64" 3-blade GSC prop has an MOI of 3200 kgcm^. If tapering took 4 oz. off each blade, I should be close. Kolb Folks, For those who are interested in the prop inertia test, here is a pdf file from Rotax Service. I found this doing an archive search, so this is not new info - it has been posted on the Kolb List before. -------- Jimmy Young Missouri City, TX Kolb FS II/HKS 700 Read this topic online here: http://forums.matronics.com/viewtopic.php?p=337281#337281 Attachments: http://forums.matronics.com//files/11ul91_2_817.pdf ________________________________ Message 7 _____________________________________ Time: 05:39:15 PM PST US Subject: Re: Kolb-List: Prop MOI From: robert bean Jimmy, although I'm not running a rotax, I get good performance from a 70" two blade WD and the weight should be closer to what you should have. Two blade hub is expensive though. BB On 17, Apr 2011, at 3:35 PM, Jimmy Young wrote: > > I ran the Rotax Service Info propeller mass moment of inertia test today on both my Powerfin 66" 2-Blade & the Warp Drive 64" 3-Blade props. Here is what I found: > > Powerfin: weight, 3.03 kg > seconds required for 30 occillations, 162 > MOI, 2700 kgcm^ > > Warp Drive: weight, 4.09 kg > seconds required for 30 occillations, 180 > MOI, 4500 kgcm^ > > Since the max. MOI for the HKS "B" box is 3000 kgcm^, I've put the Powerfin back on for now. The Warp Drive was smoother & performed better in climb and cruise on the nice/still/calm Tuesday morning I tested it, about 100 - 150 fpm climb increase and incrementally better cruise of 2 mph. What I thought was most impressive about it was I could maintain altitude at 4400 rpm vs. 4700 rpm with the Powerfin. The only conclusion I can draw from that is the Warp must be a more efficient prop on my particular plane. > > Both props made the engine run very rough if the idle speed drops to less than 1800 rpm, but both were fine once rpm's go over 2000. From what I've learned, at low idle is where most of the conflict occurs. I've always had my HKS set to idle at about 2200 rpm once it's warmed up. > > What I'm looking for is a more durable prop, which is why I wanted to use a Warp Drive. I'd like to find out what a WD 2-Blade 66" prop's MOI is without having to buy one first. My guess would be it would slightly exceed the 3000 kg limit, but if it were just by a little bit I wouldn't be concerned. > > I haven't been flying all that long, so I'm not up to date about what many of the 503 "B" box powered Kolbs that have WD props are using. The 3000 kg MOI limit applies to them as well. Can any of you long-time veterans of our sport shed any light on that? > > -------- > Jimmy Young > Missouri City, TX > Kolb FS II/HKS 700 > > > > > Read this topic online here: > > http://forums.matronics.com/viewtopic.php?p=337239#337239 > > > > > > > > > > ________________________________ Message 8 _____________________________________ Time: 08:22:51 PM PST US From: "Jack B. Hart" Subject: Re: Kolb-List: Re: Prop MOI At 05:18 PM 4/17/11 -0700, you wrote: > >I'll talk with WD tomorrow & see what suggestions they have. I should have done my research before I bought the prop, so it is on me. Maybe tapering the blades could solve the problem, since an 8.25 lb., 64" 3-blade GSC prop has an MOI of 3200 kgcm^. If tapering took 4 oz. off each blade, I should be close. > Jimmy, Ask them if they will loan you a two blade hub so you can see how it performs. It looks like a two blade may make it in under the inertia limit. Crank up the pitch, and it may perform just as well as your Powerfin. Jack B. Hart FF004 Winchester, IN ________________________________ Message 9 _____________________________________ Time: 09:32:33 PM PST US From: DAquaNut@aol.com Subject: Re: Kolb-List: Prop MOI Jimmy, I have a brand new never installed 64" Warp Drive /with tapered tips and SS LE inlay if you want to check the MOI. I've never installed it because I have always thought it was over the 3000kg. limit Ed Diebel FF# 62 In a message dated 4/17/2011 2:38:26 P.M. Central Daylight Time, jdy100@comcast.net writes: What I'm looking for is a more durable prop, which is why I wanted to use a Warp Drive. I'd like to find out what a WD 2-Blade 66" prop's MOI is without having to buy one first. My guess would be it would slightly exceed the 3000 kg limit, but if it were just by a little bit I wouldn't be concerned. I haven't been flying all that long, so I'm not up to date about what many of the 503 "B" box powered Kolbs that have WD props are using. The 3000 kg MOI limit applies to them as well. Can any of you long-time veterans of our sport shed any light on that? -------- Jimmy Young Missouri City, TX Kolb FS II/HKS 700 ________________________________ Message 10 ____________________________________ Time: 10:01:20 PM PST US Subject: Kolb-List: Re: Prop MOI From: "Richard Pike" Can you go to Mobil 1 synthetic gear oil in the HKS gear box? Since doing that in the Rotax B box, metal on the magnet at oil change has been nil, and the box is notably cooler at the end of each flight than when using mineral oil. I realize that is irrelevant to MOI, but thinking in terms of how to optimize whatever you end up with... Richard Pike MKIII N420P (420ldPoops) Read this topic online here: http://forums.matronics.com/viewtopic.php?p=337310#337310 ------------------------------------------------------------------------------------- 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.