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Jack Poller

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About Jack Poller

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    Student Poster
  1. See the PM article at http://www.popularmechanics.com/technology...aw/4316172.html
  2. See the Popular Mechanics Article at http://www.popularmechanics.com/technology...354.html?page=1
  3. When I was racing cars, where fire is a much greater concern, and wearing heavy nomex along with a fully enclosed helmet, I wore silk long-johns underneath. Summer weight silk long-johns are very comfortable, stop the itching of sweaty nomex, and won't melt in the heat like nylon. If you're concerned about fire, make sure everything is fireproof - including your underwear and socks. If you want cool suits, check out the car racing products, such as http://www.ioportracing.com/Merchant2/merc...ategory_Code=CS
  4. Maybe you can help me understand why, in all the tilt rotors, it seems necessary to swivel the entire engine housing? Wouldn't it be easier and cheaper, and much lighter to have inboard engines, and have driveshafts on sponsoons that tilt? By only moving the rotor/driveshaft sponsoon, rather than the entire engine, you're rotating a much smaller weight and can therefore reduce size/weight of the rotator components, etc. About the only downside I can see with this is getting air to the engines, but that shouldn't be too hard to solve. Or am I way off base? Thanks Jack
  5. pardon my ignorance, but what are flares and flare launchers used for?
  6. Skids: I did the same thing last September. I had to be at Buchanan to pick up someone, so scheduled an intro flight - also with Stian. When I told him I used to race cars, he also took me on the river run. For those that are interested in following, you can see the run here http://maps.google.com/maps?f=q&hl=en&...mp;t=h&z=14 just a few klicks north of CCR, cutting through the west end of Concord Naval Weapons Station. For my tour, we proceeded east along the channel, and up and over the fuel offload pier, turning south, and heading inland just before the Benicia bridge. Stian let me take the controls, and we headed south into the mountains. Over the uninhabited area, Stian showed me a pinnacle landing (no actual landing, though), along with an auto-rotation. Since then, I've been hooked, but have zero free time to take lessons. Someday..... JLP
  7. In Guitar Heroes, Michael Yon gives an excellent profile of the 4 th Squadron 6 Air Cavalry Regiment, based in Mosul Iraq.
  8. Folks: I unfortunately have the "privilege" of being in the Peoples Republic of Berkeley, California, where the city council now is actively preventing people from getting access to the military recruiting center. I don't have the time at the moment to protest against the city and the rest of the local lunatics. However, I want to say THANK YOU for your serivce to this country. Your sacrifice allows me to live in the best country in the world. Once again, THANK YOU and keep up the good work. Jack
  9. Sorry for the late reply -- I've been traveling. First, RPM and tolerances are related but are not the same thing. Second, tolerances do not dictate cooling factor. In fact, temperature is one of the factors that affects tolerances. There are hundreds of moving parts in a piston engine, and tolerances are different for each one, depending on material, load, temperature, lubrication, etc. Don't believe me - do the research - look up the tolerances yourself. As an example, a VW Type IV 2.0 Liter air-cooled motor has a crankshaft bearing minimum clearance of 0.0008" whereas the Continental IO-520 minimum is 0.0018. And both are air cooled. The big difference is the operating temperature - the Continental has to live in -50F temperatures that the VW will likely never see. Third, auto engines are definitely designed to be run at 100% of rated RPM (redline) -- in places such as on the Autobahn, in addition to Porches loafing at low RPMs at 120MPH, you'll find Peugots and Citroens and VWs all happily bouncing off their rev limiters at 120MPH. (If the manufacturers didn't design for this, the lawsuits would be horrendous.) You're mixing things up here. First you say auto engines will never have air cooling, then you site an air cooled auto engine. And you say auto engines will not have air cooling even if you put them in an aircraft. What type of logic is this? If you put an engine into an aircraft, you have to be able to cool it. If you're putting a liquid-cooled automotive engine in an airframe designed for an air-cooled engine, clearly you have to make some modifications - either to the engine to convert it to air cooling, or, more likely, to the airframe, to add ducting to a radiator. Now, let's get down to facts instead of opinions - Crank bearing clearance 1991 Acura (Honda) Integra (Liquid Cooled, Fuel Injected Inline 4): 0.0007"-.0017" VW Type-4 (Air Cooled Horiz. Opposed 4) 0.0010 - .0027" The difference is much more likely attributed to 40 years of materials science and computer controlled manufacturing than Air Cooling vs. Liquid Cooling. Please site a reference regarding auto engines at 100% RPM. Bet you can't because it's just not true. If it was, the manufacturers would be facing trillions of dollars of class-action lawsuits. And the FAA red tape and approval process is completely unrelated to the design of the engine - it exists for all engines and all manufactures. I wish you could state some facts, rather than throw platitudes around willy-nilly. There were many successful liquid cooled (not water cooled) motors developed during the WWII era. I leave it to you to come back with clearance and tolerance numbers that show differences between air cooled and liquid cooled (hint - there aren't any significant differences). The motivation during WWII was the same as it is today. The rate of heat transfer of of a radiator is much greater than that of fins for air cooling. This means that a much smaller frontal area is required, contributing to better (in general) aerodynamics. To date, you have shown little comprehension for the question at hand, little comprehension of design choices for motors, automobiles, and aircraft, and a complete lack of ability to string together two sentences into a cohesive non-contradictory paragraph. Please come back and play once you find the shift key, the spell checker, the grammar checker, and, of-course, the fact checker. Jack
  10. I think (actually, I'm quite sure) you're wrong. Tolerances may be different between aircraft and auto engines -- I don't know. If they are, it is more than likely because the Lycoming engine is a very old design, is manufactured in low numbers (compared to auto engines) and uses old manufacturing techniques, old manufacturing technology, and old tooling. Regardless, tolerances do no dictate the type of cooling required. Most aircraft engines use air cooled because, 99% of the time, the engine is moving through the air, and air cooling is cheap, easy, light weight, uses less parts, and, did I mention, it's light weight. Auto engines use liquid cooling because they have to endure long periods of running with zero airflow in very hot conditions. And, there's very little weight penalty (relatively speaking). Tolerance of components does not dictate cooling. Tolerance of components is a design factor, and is dictated by cost, type of component, use, wear allowances, technology of materials, etc., Jack
  11. Jack Poller


    The beauty of 401k is that you take the money with you. Any money you contribute is yours. Any money your employer contributes is yours (typically after a vesting period). When you leave the job, you can roll over the funds into a new 401k managed by you. You can pick any 401k management company you want. A couple of really good choices are Charles Schwab and Northwestern Mutual.
  12. Although I'm not yet flying, I have a headset question. I have a number of David Clark H8840 headsets that I use in motorsports. These appear to be the same as the DC H10-56 (with the M-101 microphone), but have a different headband. The H8840 has a behind-the-neck spring band. Over the top of the head is a small strip of fabric, split in the middle, and joined by velcro. The fabric strip adjusts the height of the earpieces relative to your ears, while the behind-the-neck spring band applies the pressure to your ears. The idea is that, most of the time in motorsports you're standing out in the sun, and therefore wearing a hat (typically, a baseball cap, but I usually wear a wide brimmed hat). Also, instead of having a volume knob, they have a push-to-talk switch. Rather than investing in yet another headset, I wanted to use what I already have (of course, with the appropriate connector adapters). Any idea of these are OK in a helicopter? Any reason not to use them? Thanks Jack
  13. I'm in about your same situation... Live in Oakland, work in San Jose. Have you looked at Bristow Academy http://www.heli.com/index.php - they originally started in Concord and claim they still do instruction there. I'm going to be at Concord for another reason and will probably check them out... Jack
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