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On Jun 2, 10:13 am, Tina wrote:
On Jun 2, 12:01 pm, "Ken S. Tucker" wrote: On Jun 1, 4:39 pm, Tina wrote: The induction port for the ram air on the m20J bypasses the air filter as well, so we typically observe about a half inch improvement in MP. That's in line with some of the other numbers offered here. I guess there's no free lunch. There is no way we want to have an IO540 pull the airplane along, nor do we want the fuss with turbo charging. The payback for our typical for real flight mission is just not there. My thought was and is that if it was something pretty obvious someone would have done it on a homebuilt. Actually, knowing some of those guys, it does not have to be obvious at all, they are really creative designers. Tina, I think this analysis you posted is good, " It's only a 360 cubic inch engine turning at 2300 RPM or so. Isn't that a demand of, let's see, at 23 inches mp at sea level that's 23/30 * 2300/2 * 360 / 12^3 or 180 cubic feet a minute? " I see Tango 2 Denny has some interesting ideas. Ken Well, I think it's a dead issue for us. What is fun to think about is, let's see, about 200 cubic feet a minute, that's 40 cubic feet of oxygen a minute, or about 3 pounds. For 50% more O2, 1.5 pounds a minute, or say 20 pounds to get to a pleasantly high altitude. Maybe that translates in to dewer weighing a total of 50 pounds with liquid O2? But it would make 15 inches of MP look like 22 or so as far as the engine is concerned. I better get back to my day job. Without crackin' the books and pounding the abacus, you look like +/- 20% using BoE (Back of Envelope) calculation, which means you get either 80% or 120% on your physics exam, you choose. Resolved: psychologists should not be permitted to minor in the physical sciences. All in favor? OR pilots should not be permitted to engage in psychology in this group, now what's the chances of that happening...is "nil" close :-). Ken PS: What's the rationale of the 12,000' cruise? You know about the "bends" don't you, if not just read Berties post! |
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On Jun 2, 2:19 pm, "Ken S. Tucker" wrote:
On Jun 2, 10:13 am, Tina wrote: On Jun 2, 12:01 pm, "Ken S. Tucker" wrote: On Jun 1, 4:39 pm, Tina wrote: The induction port for the ram air on the m20J bypasses the air filter as well, so we typically observe about a half inch improvement in MP. That's in line with some of the other numbers offered here. I guess there's no free lunch. There is no way we want to have an IO540 pull the airplane along, nor do we want the fuss with turbo charging. The payback for our typical for real flight mission is just not there. My thought was and is that if it was something pretty obvious someone would have done it on a homebuilt. Actually, knowing some of those guys, it does not have to be obvious at all, they are really creative designers. Tina, I think this analysis you posted is good, " It's only a 360 cubic inch engine turning at 2300 RPM or so. Isn't that a demand of, let's see, at 23 inches mp at sea level that's 23/30 * 2300/2 * 360 / 12^3 or 180 cubic feet a minute? " I see Tango 2 Denny has some interesting ideas. Ken Well, I think it's a dead issue for us. What is fun to think about is, let's see, about 200 cubic feet a minute, that's 40 cubic feet of oxygen a minute, or about 3 pounds. For 50% more O2, 1.5 pounds a minute, or say 20 pounds to get to a pleasantly high altitude. Maybe that translates in to dewer weighing a total of 50 pounds with liquid O2? But it would make 15 inches of MP look like 22 or so as far as the engine is concerned. I better get back to my day job. Without crackin' the books and pounding the abacus, you look like +/- 20% using BoE (Back of Envelope) calculation, which means you get either 80% or 120% on your physics exam, you choose. Resolved: psychologists should not be permitted to minor in the physical sciences. All in favor? OR pilots should not be permitted to engage in psychology in this group, now what's the chances of that happening...is "nil" close :-). Ken PS: What's the rationale of the 12,000' cruise? You know about the "bends" don't you, if not just read Berties post Depending on trip length and winds aloft, we choose as high an altitude as is reasonable without oxygen. Many of our trips are the order of 500 nm. At the moment that's often 11000 feet east bound. When we can no longer run 5k or 10ks, or find ourselves winded when walking high in the mountains or have other evidence of physical limitations (we do have access to high altitude chambers here) we'll reduce that altitude. From 12000 feet we are usually requesting lower when we're 45 minutes from the airport. When traffic permits we like coming down at 300 feet a minute! Bertie's welcome to his bends: bends would be a problem if we were going up really fast, but at 18000 feet atmospheric pressure is reduced only by 50%. 12000 feet is probably a 10 psia atmosphere, and I don't think there will be much outgassing with a difference of 5 psi, even if we went up fast (Mooneys are nice, but their climb time to altitude is not remarkable!) I think for divers that would be like coming up suddenly from maybe 10 feet down. As is clear in this group, different people flight plan differently. We choose high. There are less likely to be undisciplined pilots, or those flying under VFR, at 10,000 or 12,000 than at 3000. |
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On Mon, 2 Jun 2008 11:19:41 -0700 (PDT), "Ken S. Tucker"
wrote: On Jun 2, 10:13 am, Tina wrote: On Jun 2, 12:01 pm, "Ken S. Tucker" wrote: On Jun 1, 4:39 pm, Tina wrote: The induction port for the ram air on the m20J bypasses the air filter as well, so we typically observe about a half inch improvement in MP. That's in line with some of the other numbers offered here. I guess there's no free lunch. There is no way we want to have an IO540 pull the airplane along, nor do we want the fuss with turbo charging. The payback for our typical for real flight mission is just not there. My thought was and is that if it was something pretty obvious someone would have done it on a homebuilt. Actually, knowing some of those guys, it does not have to be obvious at all, they are really creative designers. Tina, I think this analysis you posted is good, " It's only a 360 cubic inch engine turning at 2300 RPM or so. Isn't that a demand of, let's see, at 23 inches mp at sea level that's 23/30 * 2300/2 * 360 / 12^3 or 180 cubic feet a minute? " I see Tango 2 Denny has some interesting ideas. Ken Well, I think it's a dead issue for us. What is fun to think about is, let's see, about 200 cubic feet a minute, that's 40 cubic feet of oxygen a minute, or about 3 pounds. For 50% more O2, 1.5 pounds a minute, or say 20 pounds to get to a pleasantly high altitude. Maybe that translates in to dewer weighing a total of 50 pounds with liquid O2? But it would make 15 inches of MP look like 22 or so as far as the engine is concerned. I better get back to my day job. Without crackin' the books and pounding the abacus, you look like +/- 20% using BoE (Back of Envelope) calculation, which means you get either 80% or 120% on your physics exam, you choose. Resolved: psychologists should not be permitted to minor in the physical sciences. All in favor? OR pilots should not be permitted to engage in psychology in this group, now what's the chances of that happening...is "nil" close :-). Ken PS: What's the rationale of the 12,000' cruise? You know about the "bends" don't you, if not just read Berties post! ************************************************** * Ken Have you ever talked to anyone who got the bends flying? I have thousands of hours and never have. I have gone to 43K+ and made supersonic dives to 10K +/- with no problems. I have cruised for hours at 30K cockpit pressure and no problems during let down and landing. Big John |
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On Jun 4, 7:56 am, Big John wrote:
On Mon, 2 Jun 2008 11:19:41 -0700 (PDT), "Ken S. Tucker" wrote: On Jun 2, 10:13 am, Tina wrote: On Jun 2, 12:01 pm, "Ken S. Tucker" wrote: On Jun 1, 4:39 pm, Tina wrote: The induction port for the ram air on the m20J bypasses the air filter as well, so we typically observe about a half inch improvement in MP. That's in line with some of the other numbers offered here. I guess there's no free lunch. There is no way we want to have an IO540 pull the airplane along, nor do we want the fuss with turbo charging. The payback for our typical for real flight mission is just not there. My thought was and is that if it was something pretty obvious someone would have done it on a homebuilt. Actually, knowing some of those guys, it does not have to be obvious at all, they are really creative designers. Tina, I think this analysis you posted is good, " It's only a 360 cubic inch engine turning at 2300 RPM or so. Isn't that a demand of, let's see, at 23 inches mp at sea level that's 23/30 * 2300/2 * 360 / 12^3 or 180 cubic feet a minute? " I see Tango 2 Denny has some interesting ideas. Ken Well, I think it's a dead issue for us. What is fun to think about is, let's see, about 200 cubic feet a minute, that's 40 cubic feet of oxygen a minute, or about 3 pounds. For 50% more O2, 1.5 pounds a minute, or say 20 pounds to get to a pleasantly high altitude. Maybe that translates in to dewer weighing a total of 50 pounds with liquid O2? But it would make 15 inches of MP look like 22 or so as far as the engine is concerned. I better get back to my day job. Without crackin' the books and pounding the abacus, you look like +/- 20% using BoE (Back of Envelope) calculation, which means you get either 80% or 120% on your physics exam, you choose. Resolved: psychologists should not be permitted to minor in the physical sciences. All in favor? OR pilots should not be permitted to engage in psychology in this group, now what's the chances of that happening...is "nil" close :-). Ken PS: What's the rationale of the 12,000' cruise? You know about the "bends" don't you, if not just read Berties post! ************************************************** * Ken Have you ever talked to anyone who got the bends flying? I have thousands of hours and never have. I have gone to 43K+ and made supersonic dives to 10K +/- with no problems. I have cruised for hours at 30K cockpit pressure and no problems during let down and landing. Is Mt. Everest summit at ~29K? You can get a quick overview here, http://en.wikipedia.org/wiki/Decompression_sickness Ken Big John |
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"Ken S. Tucker" wrote in
: On Jun 4, 7:56 am, Big John wrote: On Mon, 2 Jun 2008 11:19:41 -0700 (PDT), "Ken S. Tucker" wrote: On Jun 2, 10:13 am, Tina wrote: On Jun 2, 12:01 pm, "Ken S. Tucker" wrote: On Jun 1, 4:39 pm, Tina wrote: The induction port for the ram air on the m20J bypasses the air filter as well, so we typically observe about a half inch improvement in MP. That's in line with some of the other numbers offered here. I guess there's no free lunch. There is no way we want to have an IO540 pull the airplane along, nor do we want the fuss with turbo charging. The payback for our typical for real flight mission is just not there. My thought was and is that if it was something pretty obvious someone would have done it on a homebuilt. Actually, knowing some of those guys, it does not have to be obvious at all, they are really creative designers. Tina, I think this analysis you posted is good, " It's only a 360 cubic inch engine turning at 2300 RPM or so. Isn't that a demand of, let's see, at 23 inches mp at sea level that's 23/30 * 2300/2 * 360 / 12^3 or 180 cubic feet a minute? " I see Tango 2 Denny has some interesting ideas. Ken Well, I think it's a dead issue for us. What is fun to think about is, let's see, about 200 cubic feet a minute, that's 40 cubic feet of oxygen a minute, or about 3 pounds. For 50% more O2, 1.5 pounds a minute, or say 20 pounds to get to a pleasantly high altitude. Maybe that translates in to dewer weighing a total of 50 pounds with liquid O2? But it would make 15 inches of MP look like 22 or so as far as the engine is concerned. I better get back to my day job. Without crackin' the books and pounding the abacus, you look like +/- 20% using BoE (Back of Envelope) calculation, which means you get either 80% or 120% on your physics exam, you choose. Resolved: psychologists should not be permitted to minor in the physical sciences. All in favor? OR pilots should not be permitted to engage in psychology in this group, now what's the chances of that happening...is "nil" close :-). Ken PS: What's the rationale of the 12,000' cruise? You know about the "bends" don't you, if not just read Berties post! ************************************************** * Ken Have you ever talked to anyone who got the bends flying? I have thousands of hours and never have. I have gone to 43K+ and made supersonic dives to 10K +/- with no problems. I have cruised for hours at 30K cockpit pressure and no problems during let down and landing. Is Mt. Everest summit at ~29K? You can get a quick overview here, http://en.wikipedia.org/wiki/Decompression_sickness Ken You're an idiot. How's that kill file working out, BTW? Bwsawahwhahwhahwhahwhahhw! Bertie |
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On Jun 4, 10:56 am, Big John wrote:
On Mon, 2 Jun 2008 11:19:41 -0700 (PDT), "Ken S. Tucker" wrote: On Jun 2, 10:13 am, Tina wrote: On Jun 2, 12:01 pm, "Ken S. Tucker" wrote: On Jun 1, 4:39 pm, Tina wrote: The induction port for the ram air on the m20J bypasses the air filter as well, so we typically observe about a half inch improvement in MP. That's in line with some of the other numbers offered here. I guess there's no free lunch. There is no way we want to have an IO540 pull the airplane along, nor do we want the fuss with turbo charging. The payback for our typical for real flight mission is just not there. My thought was and is that if it was something pretty obvious someone would have done it on a homebuilt. Actually, knowing some of those guys, it does not have to be obvious at all, they are really creative designers. Tina, I think this analysis you posted is good, " It's only a 360 cubic inch engine turning at 2300 RPM or so. Isn't that a demand of, let's see, at 23 inches mp at sea level that's 23/30 * 2300/2 * 360 / 12^3 or 180 cubic feet a minute? " I see Tango 2 Denny has some interesting ideas. Ken Well, I think it's a dead issue for us. What is fun to think about is, let's see, about 200 cubic feet a minute, that's 40 cubic feet of oxygen a minute, or about 3 pounds. For 50% more O2, 1.5 pounds a minute, or say 20 pounds to get to a pleasantly high altitude. Maybe that translates in to dewer weighing a total of 50 pounds with liquid O2? But it would make 15 inches of MP look like 22 or so as far as the engine is concerned. I better get back to my day job. Without crackin' the books and pounding the abacus, you look like +/- 20% using BoE (Back of Envelope) calculation, which means you get either 80% or 120% on your physics exam, you choose. Resolved: psychologists should not be permitted to minor in the physical sciences. All in favor? OR pilots should not be permitted to engage in psychology in this group, now what's the chances of that happening...is "nil" close :-). Ken PS: What's the rationale of the 12,000' cruise? You know about the "bends" don't you, if not just read Berties post! ************************************************** * Ken Have you ever talked to anyone who got the bends flying? I have thousands of hours and never have. I have gone to 43K+ and made supersonic dives to 10K +/- with no problems. I have cruised for hours at 30K cockpit pressure and no problems during let down and landing. Big John John, for what it's worth, bends have to do with gas coming out of solution in the blood, and would happen if pressure was reduced too fast. Rapid descent in an airplane would increase pressure, explosive decompression would decrease it. I don't dive so don't have decompression tables at hand, but remember coming up from 34 feet in water means going to two atmospheres pressure to one. Sudden decompression from a 7000 foot cabin to a 30,000 foot actual attitude is not as great a change in pressure. It's not comparing apples with apples exactly, but changes in altitude are a lot less challenging in terms of getting bends than diving. Divers are cautioned about flying immediately after diving, it takes time for the dissolved gases to come out of the blood -- too fast makes bubbles, and bubbles in joints makes bends. |
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"Ken S. Tucker" wrote in
: On Jun 2, 10:13 am, Tina wrote: On Jun 2, 12:01 pm, "Ken S. Tucker" wrote: On Jun 1, 4:39 pm, Tina wrote: The induction port for the ram air on the m20J bypasses the air filter as well, so we typically observe about a half inch improvement in MP. That's in line with some of the other numbers offered here. I guess there's no free lunch. There is no way we want to have an IO540 pull the airplane along, nor do we want the fuss with turbo charging. The payback for our typical for real flight mission is just not there. My thought was and is that if it was something pretty obvious someone would have done it on a homebuilt. Actually, knowing some of those guys, it does not have to be obvious at all, they are really creative designers. Tina, I think this analysis you posted is good, " It's only a 360 cubic inch engine turning at 2300 RPM or so. Isn't that a demand of, let's see, at 23 inches mp at sea level that's 23/30 * 2300/2 * 360 / 12^3 or 180 cubic feet a minute? " I see Tango 2 Denny has some interesting ideas. Ken Well, I think it's a dead issue for us. What is fun to think about is, let's see, about 200 cubic feet a minute, that's 40 cubic feet of oxygen a minute, or about 3 pounds. For 50% more O2, 1.5 pounds a minute, or say 20 pounds to get to a pleasantly high altitude. Maybe that translates in to dewer weighing a total of 50 pounds with liquid O2? But it would make 15 inches of MP look like 22 or so as far as the engine is concerned. I better get back to my day job. Without crackin' the books and pounding the abacus, you look like +/- 20% using BoE (Back of Envelope) calculation, which means you get either 80% or 120% on your physics exam, you choose. Resolved: psychologists should not be permitted to minor in the physical sciences. All in favor? OR pilots should not be permitted to engage in psychology in this group, now what's the chances of that happening...is "nil" close :-). Ken PS: What's the rationale of the 12,000' cruise? You know about the "bends" don't you, if not just read Berties post! I double everyone up. Bertie |
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