---------------------------------------------------------- Kolb-List Digest Archive --- Total Messages Posted Thu 02/28/08: 36 ---------------------------------------------------------- Today's Message Index: ---------------------- 1. 02:14 AM - Re: Re: FS II perfomance (Jimmy Young) 2. 05:36 AM - Re: FireStar Cockpit Noise Reduction? (Mike Welch) 3. 05:55 AM - Re: FireStar Cockpit Noise Reduction? (John Hauck) 4. 06:21 AM - Re: FireStar Cockpit Noise Reduction? (John Hauck) 5. 06:41 AM - Re: FireStar Cockpit Noise Reduction? (johnjoyes) 6. 07:19 AM - Re: FireStar Cockpit Noise Reduction? (Richard & Martha Neilsen) 7. 07:32 AM - Rear Spar Attachment questions (jb92563) 8. 08:13 AM - Re: FireStar Cockpit Noise Reduction? (WillUribe@aol.com) 9. 08:19 AM - project engine (robert bean) 10. 09:02 AM - Re: FireStar Cockpit Noise Reduction? (WillUribe@aol.com) 11. 09:36 AM - Re: FireStar Cockpit Noise Reduction? (Mike Welch) 12. 09:42 AM - Re: FireStar Cockpit Noise Reduction? (Mike Welch) 13. 11:54 AM - Re: project engine (Richard & Martha Neilsen) 14. 12:36 PM - Re: FireStar Cockpit Noise Reduction? (jb92563) 15. 12:39 PM - Re: FireStar Cockpit Noise Reduction? (Kirby Dennis Contr MDA/AL) 16. 12:44 PM - Re: Re: FireStar Cockpit Noise Reduction? (John Hauck) 17. 12:49 PM - Re: Re: FireStar Cockpit Noise Reduction? (John Hauck) 18. 12:53 PM - Re: Re: FireStar Cockpit Noise Reduction? (John Hauck) 19. 12:53 PM - Re: Re: FireStar Cockpit Noise Reduction? (Aaron Gustafson) 20. 12:54 PM - Re: Re: FireStar Cockpit Noise Reduction? (John Hauck) 21. 03:23 PM - Re: Re: FireStar Cockpit Noise Reduction? (Larry Cottrell) 22. 03:33 PM - Re: FireStar Cockpit Noise Reduction? (Ron) 23. 03:58 PM - Re: FireStar Cockpit Noise Reduction? (Ron) 24. 04:42 PM - Re: Re: FireStar Cockpit Noise Reduction? (robert bean) 25. 05:26 PM - Re: FireStar Cockpit Noise Reduction? (Ron) 26. 05:45 PM - prop noise (william sullivan) 27. 06:00 PM - Re: Rear Spar Attachment questions (Dan Walter) 28. 06:32 PM - Dept. of Dead Horses, VG div. (Bob Noyer) 29. 08:37 PM - Re: Dept. of Dead Horses, VG div. (Denny Rowe) 30. 08:48 PM - Re: prop noise (JetPilot) 31. 08:59 PM - Re: Rear Spar Attachment questions (JetPilot) 32. 09:11 PM - 912 Engine Oil - to John Hauck (Dave Bigelow) 33. 09:16 PM - Re: FireStar Cockpit Noise Reduction? (JetPilot) 34. 09:16 PM - Re: project engine (Mike Welch) 35. 09:56 PM - Re: prop noise (DAquaNut@aol.com) 36. 09:58 PM - Re: project engine (JetPilot) ________________________________ Message 1 _____________________________________ Time: 02:14:51 AM PST US From: "Jimmy Young" Subject: Kolb-List: Re: Re: FS II perfomance Howard, My FS II cruises comfortably at about 57 mph, straight & level, no wind. That requires about 5400 rpm. I've never tried to go all out top speed wide open yet except taking off. It stalls at 36 mph. I've seen 65 mph airspeed with a 37 mph gps ground speed, and I've seen 55 mph airspeed with 85 mph gps groundspeed, depends on the wind. I've heard a lot of claims of much faster airspeeds speeds and much lower rpms, but that's the straight bull on mine. My plane weighs 440 empty, no fuel, I weigh 210. It has the 503 DCDI, 3 blade IVO prop 66". I would like to cut weight on it, but there's nothing I want to take off. I'm pretty darn happy with it just the way it is. Jimmy Young FS II, N7043P 59 hrs on it & climbing. (my time) ________________________________ Message 2 _____________________________________ Time: 05:36:41 AM PST US From: Mike Welch Subject: RE: Kolb-List: FireStar Cockpit Noise Reduction? Our good friend Carlos, Your excessive noise problem is very likely something that can greatly improved in a couple of ways. First, I HIGHLY recommend getting a set of "ACTIVE" noise-cancelling headphones. I emphasized "active" because that is the term used to describe the electronic noise cancelling system. They have the "passive" style, but that isn't what you're after. You can either buy the incredibly expensive Bose, Lightspeed, David Clarks, etc., or convert your existing David Clarks. Here is a link to an outfit that makes an active noise cancelling module for most headset companies. http://www.headsetsinc.com/customer_reviews.htm For less than $200 you can modify your present headset, and have the performance that meets or exceeds the models that cost a small fortune. A little background on the active style of noise reduction: Sound is one of the many waves along the electromagnetic wavelength spectrum. Sound is a little different from the other examples, like light, x-rays, UV rays, etc, because sound requires air to help transmit this energy from molecule to molecule, and so on. Sound comes to you by way of a sinewave. There are crests and troughs, as seen in this link; http://science.hq.nasa.gov/kids/imagers/ems/waves3.html Now, here is the really amazing and cool part. In a sense, and due to the nature of the sinewave, you are listening to either a high crest or a low trough at any given time, and according to the frequency of the sound wave coming at you. What the electronic headsets do is record the sound coming to it, and play it back virtually instaneously, where it is EXACTLY opposite of the crest and trough. In other words, if you were able to look at this new sound wave coming at you, you would see the original sinewave, and now a NEW soundwave opposite from the original (essentially a mirror image). There would be a crest...and an anti-crest, at the same time, and a trough and an anti-trough, etc. So what you are now hearing is...sound, and anti-sound, at the same moment. This added feature of "anti-sound" can and does counter-act the "sound", so that you are left with silence. For the airplane headset company, their mission is to reduce as much "bad" noise as possible, allowing you to hear only the deliberate sound from your ear speakers, and virtually all other outside noises cancelled...literally! It is possible to be in a noisy room and hear nothing. Not because the sound is muffled, but because the noise is counteracted by anti-noise, the result of which is silence. Of course, for something as small as a pair of headphones, you can't achieve such performance, but you can come close. BTW, this same exact concept of cancelling out wavelengths in the electromagnetic spectrum is shown by way of "photo-gray lenses" You've all seen the pair of glasses that the lenses get dark once they are exposed to direct sunlight, right? This phenomenon happens because the lenses have microscopic lines cut into the lenses. As sunlight (a very specific wavelength) passes through the lense some of the light is captured and refracted by the microscopic grooves. This shift is just enough to divert the light and cause it to interact with the unobstructed light. So, again, you have light wavelengths passing through the lense, and being counteracted with "opposite" lightwaves (on the electromagnetic spectrum). The result: no light (or reduced light). Essentially the light is cancelled by the anti-light, and the lense becomes dark. Of couse, photo gray lenses objective is only to reduce light, not eliminate it, so they place the microscopic grooves at such intervals as to only partially block some the light passing through, thereby making them "sunglasses". Walk back into the house, and the effect goes away, because in-door light wavelengths aren't the wavelengths that these grooves are affected by. Secondly, you may want to put an additional small muffler on your plane, or build a new system altogether. I bought a small glass pack muffler for my custom turbo installation. The muffler was still a little heavier than I wanted, so I cut it in half. I'm sure you could do a LOT in quietening down the exhaust noise. I don't know how your plane is configured, but you may consider installing a sound deadening material. I purchased a roll of this stuff for my GlaStar, to be placed against the firewall. I got it at JC Whitney, just look up "sound deadening". I am very confident these things will make a world of difference to your flying pleasure. I especially believe you will find the most improvement with the noise cancelling headset, followed by the quieter muffler improvements. I look forward to your progress reports. Mike Welch Kolb MkIII PS. One of the main reasons I chose to use the GEO engine on my MkIII was it's incredibly low engine noise. Plus, now that I have decided to use a turbo, I would be willing to bet that this will be one of the quietest MkIII's around. > I have measured the inflight cockpit noise during take-off and get about 117db on a Radio Shack Db meter. ( Not the Highest tech device but at least it gives a starting point.) > > What can a person do to reduce the noise level? (besides glide...) Even at moderate power settings the noise is still around 115 db or so. > > Help! > > Carlos G. [Crying or Very sad] _________________________________________________________________ Climb to the top of the charts!Play the word scramble challenge with star power. http://club.live.com/star_shuffle.aspx?icid=starshuffle_wlmailtextlink_jan ________________________________ Message 3 _____________________________________ Time: 05:55:19 AM PST US From: "John Hauck" Subject: Re: Kolb-List: FireStar Cockpit Noise Reduction? > I wear a helmet with a set of David-Clarks that has the Gel ear pads but for others to hear my radio transmissions, I have to reduce power to less than 3500rpm to be heard. I have my radio volume cranked up as high as it will go just to hear other pilots. It can't be doing my hearing very much good. > > Help! > > Carlos G. [Crying or Very sad] Carlos: I had to graduate from David Clarks with gel ear seals to an ANR headset. I have lived in a high noise environment most of my life. During my military career hearing protection was unheard of. My hearing has become so poor I had to graduate from passive noise reduction headsets. With the ANR I can hear and transmit quite well. Without the ANR my ability to hear and comprehend is nearly zero. I fly with a DRE6000 headset that works great. Unfortunately, this company was in business for a short time and is now belly up. john h mkIII ________________________________ Message 4 _____________________________________ Time: 06:21:27 AM PST US From: "John Hauck" Subject: Re: Kolb-List: FireStar Cockpit Noise Reduction? > Mike Welch > Kolb MkIII > > PS. One of the main reasons I chose to use the GEO engine on my MkIII was > it's incredibly low engine noise. Plus, now that I have decided to use a > turbo, I would be willing to bet that this will be one of the quietest > MkIII's around. Mike W: Once you start flying your mkIII you will probably discover the major noise producing item is the prop. By producing a very quiet engine, you will be able to hear your prop better. ;-) john h ________________________________ Message 5 _____________________________________ Time: 06:41:43 AM PST US Subject: Kolb-List: Re: FireStar Cockpit Noise Reduction? From: "johnjoyes" Forget all those suggestions of (expensive) Active Noise Reduction headsets. Sure they will help, but nowhere near as good as a pair of good in-ear noise-reduction headphones like the Shure E2C, which will cost you a tenth as much. Just pop your ordinary headset over the top, for even more noise reduction and of course to hold the microphone. I nearly gave up learning to fly because I suffered tinitus for a week after every flight, even in a "quiet" aeroplane. Now I fly my noisy Kolb in comfort, with the knowledge that I have less noise in my ears than even the most expensive Sennheiser set. Read this topic online here: http://forums.matronics.com/viewtopic.php?p=166730#166730 ________________________________ Message 6 _____________________________________ Time: 07:19:13 AM PST US From: "Richard & Martha Neilsen" Subject: Re: Kolb-List: FireStar Cockpit Noise Reduction? Carlos There are a number of things you can do. Cut the noise at the source or keep it away from you. To cut the noise at the source you can add mufflers, intake silencers and cut prop tip speeds. To cut prop noise you can shorten your prop or get a larger reduction ratio for your redrive. Most of these things will reduce your performance. Changing reduction ratios with any prop changes will be expensive. Find out where the noise is coming from first. With my direct drive VW I added a muffler and then found it was the prop that made the noise. To keep the noise away get a active noise reduction headset with a good noise canceling mike. I have the noise canceling kit in my Sigtronics headset and it helps a bunch. To get a additional level of reduction I also use a set of Sony MDR-EX51PP headphones under my active noise canceling headset. They are cheap and help a bunch. There are many others that are good and may work better. Seems like someone even found a inexpensive active noise canceling set. My set up works so well that I can listen to music at a low level with a DRE intercom cutting the music for communication and still no ringing in the ears afterwards. Rick Neilsen Redrive VW powered MKIIIC ----- Original Message ----- From: "John Hauck" Sent: Thursday, February 28, 2008 9:17 AM Subject: Re: Kolb-List: FireStar Cockpit Noise Reduction? > > > > Mike Welch >> Kolb MkIII >> >> PS. One of the main reasons I chose to use the GEO engine on my MkIII >> was it's incredibly low engine noise. Plus, now that I have decided to >> use a turbo, I would be willing to bet that this will be one of the >> quietest MkIII's around. > > > Mike W: > > Once you start flying your mkIII you will probably discover the major > noise producing item is the prop. > > By producing a very quiet engine, you will be able to hear your prop > better. ;-) > > john h > > > ________________________________ Message 7 _____________________________________ Time: 07:32:33 AM PST US Subject: Kolb-List: Rear Spar Attachment questions From: "jb92563" I was wondering about the rear spar attachment on the UltraStar. The wing rear spar fitting has a flattened steel tube that is maybe 1/4" thick and the fuselage attach "U" bracket is maybe 1" wide, leaving a big gap between the two. I know that Spar Bolts are typically designed to work in shear but by just having all that space between the two parts the bolt will likely bend a lot easier. Does this work as designed or should I be using washers/spacers to fill the void and make for a fit that I can torque down more? Not sure is this was designed to allow some flexibility and assembly freedom or not, or maybe I am just missing some assembly parts? -------- Ray Kolb UltraStar (Cuyuna UL-202) Moni MotorGlider Schreder HP-11 Glider Riverside County, CA Do Not Archive Read this topic online here: http://forums.matronics.com/viewtopic.php?p=166737#166737 ________________________________ Message 8 _____________________________________ Time: 08:13:11 AM PST US From: WillUribe@aol.com Subject: RE: Kolb-List: FireStar Cockpit Noise Reduction? Hi Carlos, 115 dB(A) is about right for my FireStar and I have an intake silencer plus the exhaust silencer. Other pilots would tell me when they heard me over the radio there was too much noise picked up by my David Clarks. The ANR works great but I found the ANR annoying to the point that on long flights it was better when I turned it off. I changed to Comtronic headsets and put the mic touching my lips, now the other pilots can hear me much better. I use Classic Foamy ear plus so I can raise the volume up and not worrying about hearing loss. The ear plus also protect me from the noise that leaks into my headsets via the sunglasses frame temples. When flying the Piper Colt I use Lightspeed QFR Soloc with the cell phone patch cord. The cell phone doesn't work unless the headsets are hooked into an intercom so I haven't tried them in my FireStar. When flying in Thom Riddle's Allegro 2000 912UL we averaged about 100 dB(A) for the durations of the flight. Regards, Will Uribe El Paso, TX FireStar II N4GU _http://www.members.aol.com/willuribe/mv/_ (http://www.members.aol.com/willuribe/mv/) do not archive -----Original Message----- From: owner-kolb-list-server@matronics.com [mailto:owner-kolb-list-server@matronics.com] On Behalf Of The BaronVonEvil Sent: Wednesday, February 27, 2008 9:45 PM Subject: Kolb-List: FireStar Cockpit Noise Reduction? Hi All, This subject may have been flogged to death already but I am to a point that if I cant get the noise level in my Firestar II down to a dull roar I will have to sell it. I have measured the inflight cockpit noise during take-off and get about 117db on a Radio Shack Db meter. ( Not the Highest tech device but at least it gives a starting point.) What can a person do to reduce the noise level? (besides glide...) Even at moderate power settings the noise is still around 115 db or so. I wear a helmet with a set of David-Clarks that has the Gel ear pads but for others to hear my radio transmissions, I have to reduce power to less than 3500rpm to be heard. I have my radio volume cranked up as high as it will go just to hear other pilots. It can't be doing my hearing very much good. Help! Carlos G. [Crying or Very sad] **************Ideas to please picky eaters. Watch video on AOL Living. (http://living.aol.com/video/how-to-please-your-picky-eater/rachel-campos-duffy/ 2050827?NCID=aolcmp00300000002598) ________________________________ Message 9 _____________________________________ Time: 08:19:05 AM PST US From: robert bean Subject: Kolb-List: project engine For those with ambition, patience, and maybe a high mental pain threshold here's something to look at: (paste at eBay) 130201933456 BB do not archive ________________________________ Message 10 ____________________________________ Time: 09:02:45 AM PST US From: WillUribe@aol.com Subject: RE: Kolb-List: FireStar Cockpit Noise Reduction? Sorry, I meant ear plugs not ear plus. My right hand types faster them my left. (http://us.st11.yimg.com/us.st.yimg.com/I/earplugstore_1986_20967346) In a message dated 2/28/2008 9:14:21 A.M. Mountain Standard Time, WillUribe@aol.com writes: I use Classic Foamy ear plus so I can raise the volume up and not worrying about hearing loss. The ear plus also protect me from the noise that leaks into my headsets via the sunglasses frame temples. do not archive **************Ideas to please picky eaters. Watch video on AOL Living. (http://living.aol.com/video/how-to-please-your-picky-eater/rachel-campos-duffy/ 2050827?NCID=aolcmp00300000002598) ________________________________ Message 11 ____________________________________ Time: 09:36:01 AM PST US From: Mike Welch Subject: RE: Kolb-List: FireStar Cockpit Noise Reduction? Will, Thanks for clearing that typo up. I kept doing a Google search, and all I could could with is pictures of Dumbo. he he he Mike Welch Do not archive ________________________________ From: WillUribe@aol.com Subject: RE: Kolb-List: FireStar Cockpit Noise Reduction? Sorry, I meant ear plugs not ear plus. My right hand types faster them my left. In a message dated 2/28/2008 9:14:21 A.M. Mountain Standard Time, WillUribe@aol.com writes: I use Classic Foamy ear plus so I can raise the volume up and not worrying about hearing loss. The ear plus also protect me from the noise that leaks into my headsets via the sunglasses frame temples. do not archive ________________________________ Delicious ideas to please the pickiest eaters. Watch the video on AOL Living. _________________________________________________________________ Need to know the score, the latest news, or you need your Hotmail-get your "fix". http://www.msnmobilefix.com/Default.aspx ________________________________ Message 12 ____________________________________ Time: 09:42:13 AM PST US From: Mike Welch Subject: RE: Kolb-List: FireStar Cockpit Noise Reduction? > Mike W: > > Once you start flying your mkIII you will probably discover the major noise > producing item is the prop. > > By producing a very quiet engine, you will be able to hear your prop better. > ;-) > > john h > Ah, John, With very little MkIII flying time (read that to be "none"), I wouldn't know that the prop makes that much noise. But I really do believe I should have a very quiet engine, and I figured if the prop was a problem, then I would just install VGs on it. chuckling Mike Welch _________________________________________________________________ Helping your favorite cause is as easy as instant messaging.You IM, we give. ________________________________ Message 13 ____________________________________ Time: 11:54:57 AM PST US From: "Richard & Martha Neilsen" Subject: Re: Kolb-List: project engine Bob/All This would be a very inexpensive option for a Kolb. It would be a bit low on power for one of the big Kolbs but with a two bladed prop, for slightly more thrust, it might work ok. Robert seems happy. The laydown engine configuration (more specifically the redrive or prop center line) might allow one to use the stock Kolb engine mount. The lower thrust of this engine would allow it to work with a slightly higher thrust line than an engine with lots of thrust. There has been talk of using a turbo on these engines. Wouldn't the turbo shorten the life of the engine quite a bit? Would it become dangerous? If the engine were designed to use a turbo and only used on takeoff maybe? Even so you would have to run the engine at a higher power level than it is designed for to even get a 65MPH cruise? Would this be a better choice for a Firestar II?? Rick Neilsen Redrive VW Powered MKIIIC ----- Original Message ----- From: "robert bean" Sent: Thursday, February 28, 2008 11:16 AM Subject: Kolb-List: project engine > > For those with ambition, patience, and maybe a high mental pain threshold > here's something to look at: > > (paste at eBay) 130201933456 > > BB > do not archive > > > ________________________________ Message 14 ____________________________________ Time: 12:36:09 PM PST US Subject: Kolb-List: Re: FireStar Cockpit Noise Reduction? From: "jb92563" For transmitting I have recently seen some throat microphones that basically rest on your neck and pick up you voice through direct skin contact, and muffle some of the other external noises. ANR Headphones are great as well. Muffler is a good idea if that is where your noise is coming from, as many times its the prop that is actually creating the most noise. Prop noise occurs as the tips approach the speed of sound. If they are spinning to fast you need higher pitch and less diameter to reduce noise. Do a google search on "propeller tip speed" and you will find calculators to input your diameter and rpm to determine if your tips are going to fast. Should be under 600 mph tip speed to reduce noise from the prop. -------- Ray Kolb UltraStar (Cuyuna UL-202) Moni MotorGlider Schreder HP-11 Glider Riverside County, CA Do Not Archive Read this topic online here: http://forums.matronics.com/viewtopic.php?p=166787#166787 ________________________________ Message 15 ____________________________________ Time: 12:39:47 PM PST US Subject: Kolb-List: Re: FireStar Cockpit Noise Reduction? From: "Kirby Dennis Contr MDA/AL" << I cant get the noise level in my Firestar II down to a dull roar I will have to sell it. >> Carlos - I had the same problem in my Mark-III. It was almost impossible to hear my radio, even with a well-fitting Comtronics helmet with built-in gel earseal headsets. The single most effective thing you can do is get yourself a set of ANR (Active Noise Reduction) headsets. MAN, what a difference they made for me! I bought the least-expensive set I could find on the market - LightSPEED QXC. The cost me about $275. Worth every penny. Sure, there are more expensive sets on the market, and they may perform better. But just making the step up to any ANR headset (even an entry-level one) is an order of magnitude better than any passive set you can buy. Dennis Kirby Mark-III Classic, 912ul Cedar Crest, NM ________________________________ Message 16 ____________________________________ Time: 12:44:16 PM PST US From: "John Hauck" Subject: Re: Kolb-List: Re: FireStar Cockpit Noise Reduction? ----- Original Message ----- From: "jb92563" Sent: Thursday, February 28, 2008 2:33 PM Subject: Kolb-List: Re: FireStar Cockpit Noise Reduction? > > For transmitting I have recently seen some throat microphones that > basically rest on your neck and pick up you voice through direct skin > contact, and muffle some of the other external noises. > > ANR Headphones are great as well. > > Muffler is a good idea if that is where your noise is coming from, as many > times its the prop that is actually creating the most noise. > > Prop noise occurs as the tips approach the speed of sound. > > If they are spinning to fast you need higher pitch and less diameter to > reduce noise. > > Do a google search on "propeller tip speed" and you will find calculators > to input your diameter and rpm to determine if your tips are going to > fast. > > Should be under 600 mph tip speed to reduce noise from the prop. > > -------- > Ray > > Kolb UltraStar (Cuyuna UL-202) > Moni MotorGlider > Schreder HP-11 Glider > Riverside County, CA > > Do Not Archive > > > Read this topic online here: > > http://forums.matronics.com/viewtopic.php?p=166787#166787 > > > ________________________________ Message 17 ____________________________________ Time: 12:49:13 PM PST US From: "John Hauck" Subject: Re: Kolb-List: Re: FireStar Cockpit Noise Reduction? > > Should be under 600 mph tip speed to reduce noise from the prop. > > -------- > Ray Hi Ray: We've knocked this noise thing around quite a bit over the years. I'd say it it more prop noise than anything else. Also, I think we can discount prop tips approaching or exceeding supersonic speeds. The Rotax engines have already taken that into consideration for us. I believe most of our noise is the result of a pusher engine configuration with a prop that must run through air that is not always clean and in close proximity to the aircraft structure. I have gotten down to the point where I accept my noisy airplane and try to take other routes to help make it liveable for long flights. Some of us have proven that it is not so excessive we can not live in our airplanes for very long periods of time. john h mkIII Noisy beyond imagination. ________________________________ Message 18 ____________________________________ Time: 12:53:01 PM PST US From: "John Hauck" Subject: Re: Kolb-List: Re: FireStar Cockpit Noise Reduction? > The single most effective thing you can do is get yourself a set of ANR > (Active Noise Reduction) headsets. MAN, what a difference they made for > me! > > Dennis Kirby Dennis: Got your bag packed for MV? I tried the best Litespeed had to offer when they first came out without success. Then, last summer, I bought the best that David Clark had to offer the XL somethings. Neither would work in the mkIII cockpit. The set that worked best for me was the DRE6000, which unfortunately, is out of business. Got my fingers crossed my old set will keep on trucking. john h mkIII Bag packed for MV 2008. ________________________________ Message 19 ____________________________________ Time: 12:53:35 PM PST US From: "Aaron Gustafson" Subject: Re: Kolb-List: Re: FireStar Cockpit Noise Reduction? I noticed on my FS2 when I changed from the Culver wood prop to an IVO and had to add the 3" extension that the noise went down considerably and I think only slightly because of the prop. Before I could not keep the gap seal in place (would shred) near the prop but getting the prop away from the TE nearly solved that problem and was where the most of the noise was coming from I think. Ear plugs and a helmet, it never bothered me, but no radio installed. Aaron G. ________________________________ Message 20 ____________________________________ Time: 12:54:25 PM PST US From: "John Hauck" Subject: Re: Kolb-List: Re: FireStar Cockpit Noise Reduction? Sorry Folks: Looks like I fired a blank. The real one will follow shortly. john h mkIII ________________________________ Message 21 ____________________________________ Time: 03:23:46 PM PST US From: "Larry Cottrell" Subject: Re: Kolb-List: Re: FireStar Cockpit Noise Reduction? I only want to add a couple of things about the noise in a Kolb. A prop extension will help a lot, all mikes on anr type headsets are directional. This is where anyone has trouble hearing you transmit. Put the mike on the other side and see if that helps. Larry C ________________________________ Message 22 ____________________________________ Time: 03:33:52 PM PST US From: Ron Subject: Re: Kolb-List: FireStar Cockpit Noise Reduction? Get one of their mods ASAP. http://www.headsetsinc.com/ ============================================= ---- The BaronVonEvil wrote: ============ Hi All, This subject may have been flogged to death already but I am to a point that if I cant get the noise level in my Firestar II down to a dull roar I will have to sell it. I have measured the inflight cockpit noise during take-off and get about 117db on a Radio Shack Db meter. ( Not the Highest tech device but at least it gives a starting point.) What can a person do to reduce the noise level? (besides glide...) Even at moderate power settings the noise is still around 115 db or so. I wear a helmet with a set of David-Clarks that has the Gel ear pads but for others to hear my radio transmissions, I have to reduce power to less than 3500rpm to be heard. I have my radio volume cranked up as high as it will go just to hear other pilots. It can't be doing my hearing very much good. Help! Carlos G. [Crying or Very sad] Read this topic online here: http://forums.matronics.com/viewtopic.php?p=166684#166684 -- kugelair.com ________________________________ Message 23 ____________________________________ Time: 03:58:25 PM PST US From: Ron Subject: RE: Kolb-List: FireStar Cockpit Noise Reduction? Do you have a link to the optical cancellation you mentioned. I have not heard of it before. ======================== ---- Mike Welch wrote: ============ Our good friend Carlos, Your excessive noise problem is very likely something that can greatly improved in a couple of ways. First, I HIGHLY recommend getting a set of "ACTIVE" noise-cancelling headphones. I emphasized "active" because that is the term used to describe the electronic noise cancelling system. They have the "passive" style, but that isn't what you're after. You can either buy the incredibly expensive Bose, Lightspeed, David Clarks, etc., or convert your existing David Clarks. Here is a link to an outfit that makes an active noise cancelling module for most headset companies. http://www.headsetsinc.com/customer_reviews.htm For less than $200 you can modify your present headset, and have the performance that meets or exceeds the models that cost a small fortune. A little background on the active style of noise reduction: Sound is one of the many waves along the electromagnetic wavelength spectrum. Sound is a little different from the other examples, like light, x-rays, UV rays, etc, because sound requires air to help transmit this energy from molecule to molecule, and so on. Sound comes to you by way of a sinewave. There are crests and troughs, as seen in this link; http://science.hq.nasa.gov/kids/imagers/ems/waves3.html Now, here is the really amazing and cool part. In a sense, and due to the nature of the sinewave, you are listening to either a high crest or a low trough at any given time, and according to the frequency of the sound wave coming at you. What the electronic headsets do is record the sound coming to it, and play it back virtually instaneously, where it is EXACTLY opposite of the crest and trough. In other words, if you were able to look at this new sound wave coming at you, you would see the original sinewave, and now a NEW soundwave opposite from the original (essentially a mirror image). There would be a crest...and an anti-crest, at the same time, and a trough and an anti-trough, etc. So what you are now hearing is...sound, and anti-sound, at the same moment. This added feature of "anti-sound" can and does counter-act the "sound", so that you are left with silence. For the airplane headset company, their mission is to reduce as much "bad" noise as possible, allowing you to hear only the deliberate sound from your ear speakers, and virtually all other outside noises cancelled...literally! It is possible to be in a noisy room and hear nothing. Not because the sound is muffled, but because the noise is counteracted by anti-noise, the result of which is silence. Of course, for something as small as a pair of headphones, you can't achieve such performance, but you can come close. BTW, this same exact concept of cancelling out wavelengths in the electromagnetic spectrum is shown by way of "photo-gray lenses" You've all seen the pair of glasses that the lenses get dark once they are exposed to direct sunlight, right? This phenomenon happens because the lenses have microscopic lines cut into the lenses. As sunlight (a very specific wavelength) passes through the lense some of the light is captured and refracted by the microscopic grooves. This shift is just enough to divert the light and cause it to interact with the unobstructed light. So, again, you have light wavelengths passing through the lense, and being counteracted with "opposite" lightwaves (on the electromagnetic spectrum). The result: no light (or reduced light). Essentially the light is cancelled by the anti-light, and the lense becomes dark. Of couse, photo gray lenses objective is only to reduce light, not eliminate it, so they place the microscopic grooves at such intervals as to only partially block some the light passing through, thereby making them "sunglasses". Walk back into the house, and the effect goes away, because in-door light wavelengths aren't the wavelengths that these grooves are affected by. Secondly, you may want to put an additional small muffler on your plane, or build a new system altogether. I bought a small glass pack muffler for my custom turbo installation. The muffler was still a little heavier than I wanted, so I cut it in half. I'm sure you could do a LOT in quietening down the exhaust noise. I don't know how your plane is configured, but you may consider installing a sound deadening material. I purchased a roll of this stuff for my GlaStar, to be placed against the firewall. I got it at JC Whitney, just look up "sound deadening". I am very confident these things will make a world of difference to your flying pleasure. I especially believe you will find the most improvement with the noise cancelling headset, followed by the quieter muffler improvements. I look forward to your progress reports. Mike Welch Kolb MkIII PS. One of the main reasons I chose to use the GEO engine on my MkIII was it's incredibly low engine noise. Plus, now that I have decided to use a turbo, I would be willing to bet that this will be one of the quietest MkIII's around. > I have measured the inflight cockpit noise during take-off and get about 117db on a Radio Shack Db meter. ( Not the Highest tech device but at least it gives a starting point.) > > What can a person do to reduce the noise level? (besides glide...) Even at moderate power settings the noise is still around 115 db or so. > > Help! > > Carlos G. [Crying or Very sad] _________________________________________________________________ Climb to the top of the charts!Play the word scramble challenge with star power. http://club.live.com/star_shuffle.aspx?icid=starshuffle_wlmailtextlink_jan -- kugelair.com ________________________________ Message 24 ____________________________________ Time: 04:42:22 PM PST US From: robert bean Subject: Re: Kolb-List: Re: FireStar Cockpit Noise Reduction? The fact that we are sitting at the focal point of a cone shaped megaphone is the problem. If we move our seats out in front of the windshield it will be a lot quieter. -or maybe a sound diffuser behind our backs. BB do not archive On 28, Feb 2008, at 3:46 PM, John Hauck wrote: > > >> >> Should be under 600 mph tip speed to reduce noise from the prop. >> >> -------- >> Ray > > > Hi Ray: > > We've knocked this noise thing around quite a bit over the years. > I'd say it it more prop noise than anything else. Also, I think we > can discount prop tips approaching or exceeding supersonic speeds. > The Rotax engines have already taken that into consideration for us. > > I believe most of our noise is the result of a pusher engine > configuration with a prop that must run through air that is not > always clean and in close proximity to the aircraft structure. > > I have gotten down to the point where I accept my noisy airplane > and try to take other routes to help make it liveable for long > flights. Some of us have proven that it is not so excessive we can > not live in our airplanes for very long periods of time. > > john h > mkIII Noisy beyond imagination. > > ________________________________ Message 25 ____________________________________ Time: 05:26:41 PM PST US From: Ron Subject: RE: Kolb-List: FireStar Cockpit Noise Reduction? The problem with VG's on the prop is that you will always have lots of Thrust. Even after you shut the engine down. You will need to install thrust nualifiers to keep your airplane from taking off and disappearing into the sky, perpetually loitering in the heavens. =================================================== ---- Mike Welch wrote: ============ > Mike W: > > Once you start flying your mkIII you will probably discover the major noise > producing item is the prop. > > By producing a very quiet engine, you will be able to hear your prop better. > ;-) > > john h > Ah, John, With very little MkIII flying time (read that to be "none"), I wouldn't know that the prop makes that much noise. But I really do believe I should have a very quiet engine, and I figured if the prop was a problem, then I would just install VGs on it. chuckling Mike Welch _________________________________________________________________ Helping your favorite cause is as easy as instant messaging.You IM, we give. -- kugelair.com ________________________________ Message 26 ____________________________________ Time: 05:45:55 PM PST US From: william sullivan Subject: Kolb-List: prop noise I noticed the prop noise exceeded the engine noise while having my Firestar tied to a tree. Without the wings, as soon as the RPM's got up to about 4000, the prop started sounding like a helicopter. There is also a spot on the main boom tube right below the prop that is missing the paint. Maybe the prop tips passing 1" from the tube is generating the "whopping" noise. It is a 66" Warp Drive 2 blade ground adjustable prop. I never went past 4000rpm, as we were worried about both the tree and the rope. I imagine the noise will be quite a bit louder when the wings are on, as I have to check for aileron clearance to the prop. If the prop is too close to the ailerons, will it give the aircraft a horizontal trim problem? I have looked a pictures of Firestars with both long (close to the prop) and short (lots of clearance) ailerons. How much difference is there in ease of handling, control response, and trim? What would be the recommended minimum clearance? It doesn't look too difficult to take a couple of sections out of the aileron, but should I? Bill Sullivan Old Firestar ________________________________ Message 27 ____________________________________ Time: 06:00:19 PM PST US From: "Dan Walter" Subject: Re: Kolb-List: Rear Spar Attachment questions ----- Original Message ----- From: "jb92563" Sent: Thursday, February 28, 2008 10:29 AM Subject: Kolb-List: Rear Spar Attachment questions > > I was wondering about the rear spar attachment on the UltraStar. Same on My Ultrastar. I use a pin and clip and no spacers and have had no problems in 175 hours. Dan Walter Ultrastar, Turbulent Do not archive ________________________________ Message 28 ____________________________________ Time: 06:32:18 PM PST US From: Bob Noyer Subject: Kolb-List: Dept. of Dead Horses, VG div. I'm working on VVGs (variable vector generators) with my Irish asst, Pat Pending. Through our semi-complex electro-mechanical linkages, aka lotsa rods, reels, shafts, and idlers..as best represented by Ferguson's Paradox, we envision many breakthroughs. This will allow VGs to be variably converted into variable vector drag generators, which will then take the place of such drag generators as used on glider wings, wing flaps, dual lift struts, and more importantly, the use of vvgs on propellers, to be used as "aerobrakes." By the mere flip-of-a-switch the vehicle driver may use his vvg- equipped propeller to both advance his machine into the air, to slow (or even stop in the air if his engine has enough power), and to back into his hangar! One area still not refined is the use of wooden propellers, which do not seem to offer enough hollow volume for the complex linkages. A neutral setting, called the Hauck, will be provided for those operators who do not want any addition or subtractions afforded by our vvgs. And, although the linkages will be machined by Rolex=99 we have formed a partnership with SeaFoam=99 for lubrication of the vvgs. As soon as my medication arrives wil tr t end m o if nnno . fer pte"s sak do not archive regards, Bob N. FireFly 070 Old Kolb http://www.angelfire.com/rpg/ronoy/ ________________________________ Message 29 ____________________________________ Time: 08:37:44 PM PST US From: "Denny Rowe" Subject: Re: Kolb-List: Dept. of Dead Horses, VG div. Grinning, Thanks Grey Baron Do not archive ________________________________ Message 30 ____________________________________ Time: 08:48:16 PM PST US Subject: Kolb-List: Re: prop noise From: "JetPilot" One inch of boom clearance is not very much, I have more on my MK III. The closer the prop tips are to both the boom and ailerons, the more noise it will generate. You should us a prop extension rather than cut out your ailerons for more clearance. Mike -------- "NO FEAR" - If you have no fear you did not go as fast as you could have !!! Kolb MK-III Xtra, 912-S Read this topic online here: http://forums.matronics.com/viewtopic.php?p=166870#166870 ________________________________ Message 31 ____________________________________ Time: 08:59:31 PM PST US Subject: Kolb-List: Re: Rear Spar Attachment questions From: "JetPilot" There is very little stress on the rear spar attachment on a Kolb. The forces involved insignificant compared to what you would find on attach points of the main spar and the struts. You are correct that the bolt is not as strong in bending as in shear, but given the little amount of force on a rear spar of a Kolb, I would not think it would ever make a bolt fail. You should post some pictures of the place you are talking about, but be aware and be very careful, some parts of a Kolb are designed to have play in them, and that tightening them againste each other rather than allowing them to " Float " freely can cuase fatigue from bending and vibration that will cause something to fail. Mike -------- "NO FEAR" - If you have no fear you did not go as fast as you could have !!! Kolb MK-III Xtra, 912-S Read this topic online here: http://forums.matronics.com/viewtopic.php?p=166871#166871 ________________________________ Message 32 ____________________________________ Time: 09:11:45 PM PST US Subject: Kolb-List: 912 Engine Oil - to John Hauck From: "Dave Bigelow" HKS recently put out a factory bulletin regarding fuel and engine oil. In a nutshell, they say not to use fuel with more than 5% ethanol, and lower than 91 octane. Aviation gas is OK. They say to only use synthetic automotive oil. The 4 stroke Rotax and HKS engines share many similarities. In my case, I can get 89 octane gas with no ethanol. I blend that 3:1 with 100/130 octane avgas to end up with gas that is above 91 octane. It is known that leaded gas and synthetic oil are not a good combination, but it appears that HKS owners are locked in to using synthetic automotive oil. John, you probably have more 912 time than anyone alive. I know you use avgas during your cross-country trips, mainly because that is all you can get at many airports. How have you dealt with the lead/synthetic oil problem? -------- Dave Bigelow Kamuela, Hawaii FS2, HKS 700E Read this topic online here: http://forums.matronics.com/viewtopic.php?p=166872#166872 ________________________________ Message 33 ____________________________________ Time: 09:16:33 PM PST US Subject: Kolb-List: Re: FireStar Cockpit Noise Reduction? From: "JetPilot" My MK III Xtra was very noisey, the prop noise going into a huge megaphone is a very good description of the problem. The good news is that the noise can be fixed, and a Kolb can become pretty quiet. On my MK III Xtra, I put 1/2 inch ductboard in the Cabin anywhere it faces the prop, and also under the engine ( Center Section ). Ductboard is rigid, fireproof, oil and fuel proof on the foil side, and does a fair job of dapening sound. I installed ductboard inside the lexan rear windows, and closed the back space of the cage where it goes against the prop. This was so successful in reducing the noise, that I can now communicate normally in the plane with headsets and intercomm, I could not before... The plane is now enjoyable to fly for long periods of time with out fatigue. I did lose my view to the rear, but it was well worth it. I dont directly behind me much, and given the choice of having an airplane that I could not fly without going deaf, and one that is comfortable to fly, losing the rear visibility is a very good tradeoff. Second, I do use ANR headsets. The ANR headsets did not work well alone with the huge roar of noise inside my life sized megaphone of a cockpit, but the headsets along with the ductboard made noise a Non - Issue in my plane. I will post pictures soon. Mike -------- "NO FEAR" - If you have no fear you did not go as fast as you could have !!! Kolb MK-III Xtra, 912-S Read this topic online here: http://forums.matronics.com/viewtopic.php?p=166873#166873 ________________________________ Message 34 ____________________________________ Time: 09:16:59 PM PST US From: Mike Welch Subject: RE: Kolb-List: project engine Rick N., If a person put a mild turbo on that one liter engine, I do not think it would shorten the life of the engine to any depreciable degree. The turbo I am mounting on my GEO 1.0L engine is about the littlest turbo you ever saw, in fact, I bet it is the littlest turbo you ever saw!! It is made by Garrett, the 1544 model, made for engines around 800 to 1000cc range. By its size alone, it couldn't produce much boost. Besides it's own limitations, I don't want it to put out too much boost. The stock engine computer can handle barimetric changes up to 5-6psi (above atmospheric). Meaning, if I limit the boost to 5psi, the O2 sensor and MAP (manifold air pressure) sensor can adjust the fuel flow automatically, by way of the standard throttle body fuel injection. Most peoples knowledge of turbos come from automobile applications. In those situations, the engines are made to be borderline timebombs, sometimes doubling or tripling the original engines hp and torque rating. I read all kinds of ads on eBay about people claiming this turbo will produce 20lbs or 30 pounds , etc. of boost. For an airplane that would be obscene!! For a dragcar it's really cool! (for a few minutes) For those that aren't very familiar with turbos and boost, here is some basics: A normally aspirated engine has to suck air in as the pistons are on their downstroke. Atmospheric pressure is 14.7 psi at sea level. As your car engine is running, the ECU (Electronic Control Unit) computer, by way of the fuel injection, supplies the perfect amount of fuel at a given atmospherpressure. If you climb in elevation,,,say, from Long Beach to Denver, the computer senses less oxygen (by way of the O2 sensor) and leans the fuel to the appropriate amount. If you happen to drive "down" to Death Valley where you are below sea level, the the computer richen the fuel level a bit, because atmospheric pressure is slightly greater below sea level. This ability to adjust the fuel/air ratio is one of the HUGE advantages of using an auto engine conversion. Especially if you are going to put a MILD turbo on it. If you want to build a screamer, then that's another matter, but for a little bit of boost, then things are just fine. So, what the heck does adding boost do? Here's what: Remember we said barometric pressure is 14.7 psi. According to the fundamentals of physics, if an engine is running properly with it's fuel/air ratio, and it is normally aspirated, and this engine produces....say 100 HP at 3900 rpm. If you force more air....say about 5 psi, by way of a turbo, and the computer makes the appropriate fuel adjustment, we will have increased the power the same amount as the boost percentage of atmospheric...which we said is 1/3 of atmospheric (we are assuming the 5psi is about 1/3rd of 14.7...yeah, I know, but it's close) Our power output in this example is now increased by 1/3rd, namely 133 HP. That's a fact, and one of the fundamentals of a "heat engine" (If you took Thermodynamics in college.) If we add 15 lbs. of boost(which would be 2 atmospheric pressures, our engine will produce TWICE it's original HP output, and if we give it 30 psi (that would be 3 atmos pressures, etc.)and so on. But as usual, in physics, there ain't no free lunch, as they say!!! You do not get every bit of your added boost back in usable performance. Some energy is used up in turning the turbo (or supercharger, which is a belt driven turbo). Some energy is lost in the added back-pressure of spinning the turbo. So, you do lose "some" of the added power, to normal devices and friction, etc. to acheive this extra power, but you do get to keep the lion's share in raw added performance!! In my particular application, I have a run-of-the-mill basic grocery getter GEO Metro engine. About 1000cc, and supposedly puts out about 62 HP. By adding a small turbo, I should see around 75-80 HP, and about 107 ftlbs. of torque. The GEO achieves these torque and horsepower figures of performance at about 1000rpm less than a Rotax 912 does. A quick check of the Rotax 912 performance numbers says the 912UL has about 76 ftlbs of torque @4800 rpm. The 912S has about 96 ftlbs of torque @ 5100 rpm. The GEO with a turbo (according to GEO Corp.) has 107 ftlbs. of torque at around 3900rpm. By allowing the significantly reduced lower cruise rpm, and corresponding noise/prop/fuel reduction, this is what I am told by those that have this setup obtain. We shall see! If I set my cruise rpm to around 3500 (well into the power band and still possibly exceeding a Rotax 912S's maximum torque), the propeller swings @ 1555 rpm( I have a 2.25 to 1 reduction). By being able to adjust the prop pitch (by way of the Ivo Electric In-Flight adjustable propeller), this should make a very quiet, fuel efficient, fairly strong powerplant. This is also how a GEO and turbo combination is able to claim a fuel burn of about 1.75 gal/hr. As I have previously said..."we'll see". These are the things I've heard, and read, and am told by those that have a GEO with turbo. I make no claims until I experience these results myself. BFN, Mike Welch Disclaimer: This is email is NOT meant to be disparaging to any Rotax owners! If you have a Rotax, and are happy with it, then I am happy for you. Rotax is a fine engine. They're the best! You are NOT a fool, a moron, an idiot or any other insulting name if your opinion and experiences differ from mine. You do not need to agree with me, nor do you have to buy a GEO engine and try it out. You are not required to have a contest of a GEO against a Rotax, carried out in ideal weather conditions. And finally, the opinions stated here are my own, your mileage may vary, and that's okay by me. _________________________________________________________________ Connect and share in new ways with Windows Live. http://www.windowslive.com/share.html?ocid=TXT_TAGHM_Wave2_sharelife_012008 ________________________________ Message 35 ____________________________________ Time: 09:56:06 PM PST US From: DAquaNut@aol.com Subject: Re: Kolb-List: prop noise Bill, A prop spacer should help if you don't have one. Ed FF # 62 ( working on wing) **************Ideas to please picky eaters. Watch video on AOL Living. (http://living.aol.com/video/how-to-please-your-picky-eater/rachel-campos-duffy/ 2050827?NCID=aolcmp00300000002598) ________________________________ Message 36 ____________________________________ Time: 09:58:19 PM PST US Subject: Kolb-List: Re: project engine From: "JetPilot" Mike, While you are claiming to be this nice guy that would never say anything bad, you are are taking any opportunity you can to take a cheap shot at me here on the list. No matter what you say, your actions speak louder than your words. There is also a very big difference between opinion and FACT. I dont care much about your or other peoples opinions, that is up to them. When people dismiss FACTS and give bad information to others, then you could use any of the terms in your above post to describe them. People come to this list to get good information, and it is our responsibility to give them the best information possible. The only time I have a problem with what some post is when a few individuals like yourself put list politics, and saving face above giving truthful and accurate information to the many people that read this list. Mike Bigelow -------- "NO FEAR" - If you have no fear you did not go as fast as you could have !!! 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