t_andrews

Interesting item which may or may not be related... http://thermocompass.orgfree.com/index1.html

Even water cooling doesn't extended valve life. Probably cook some corn pretty quick though... [youtubevideo] [/youtubevideo]

Dune gooning will be my motivator to become biwingual. You can't beat the setup time for a ragwing, but HGs have certain advantages for sure. These guys have some airtime behind them.

Awesome.

See: http://spectrumled.com/fixtures.htm Search the page for "Super Bright Strobe Light Kits" These are xenon, tuneable flash interval and run on 10-14.5v. Ring in at $6 and weigh very little. Strobes are embedded in clear acrylic and are waterproof and indestructible in daily use, including cage mount. Control board is vibe sensitive and requires potting/filling in silicone to avoid shaking a large capacitor off the board over time, but easy mod. Cheapest strobe I've found and wired into my battery on a common switch with my low fuel warning LED. I extended the leads with RC three wire extensions for easy disconnect with cage quadrants. If you forget to turn them off when disconnecting, they will even remind you (bzzt).

I think the trailing edge sand has been refuted in another discussion. One should note the prevailing winds @ 0.29 on the water plyon, that is was indeed a beach in Southern US, and risks were being taken to finish the course quickly in a sanctioned event. My theory is a thermal beach release was triggered by the presence of the pylon and his left edge just happened to be in the lee of the pylon when it happened. While he did get off bar very quickly which would explain some of the pop, the turn happened quicker then a simple assymetric collapse would warrant. Thermic lift may have contributed to that as well, but it's all theory. He brakes quickly to reinflate, which very likely slowed his horizontal motion although he may have traded some of it for vertical. The winds were not calm at all, although he makes it look that way. Skillz. As sore as he must be healing bones, it could have been much worse due to proximity of hard things where he landed. Glad he's on the mend.

If you see a Typhoon flying in front of you, there's a good chance your wing is gonna get rocked! I wonder if that may be misinterpreted

Don't know who the pilot was, but they simply didn't consider rotor on a low downwind over that "structure". The result was predictable except to them. Silly rabbit. Did they even plan to land inside the facility or do a classic outside land and dash... They're lucky it went parachutal at least.

We best enjoy it while it lasts - geologically speaking... http://www.space.com/3373-earth-moon-de ... grate.html Rings would be cool. Surfing the solsphere not so much.

I bet propless it was shaking more than you could see: [youtubevideo] [/youtubevideo](This probably had a prop, who knows) It's pretty common to hear belt squeak when a motor is cold and it's four or eight cycling like at the end of that video. When my mini2/3blade is warm, it idles without squeak and *seems* amazingly smooth. The prop acts as a mass damper to the engine pulses and acts backwards on four cycling, causing the belt chirps on subsequent firing. At higher rpms it damps them better, and even more so when every cycle fires. With no prop, there is nothing to react against (torquewise) other then the low mass of the engine and eyeballs aren't that fast. With mass to counter the pulses, it gets uglier on idle: [youtubevideo]http://www.youtube.com/watch?v=Vw8z9msIHEE[/youtubevideo]

Dmwood nailed it. Thrust is just thrust. Knowing how much you need: 1) skill level 2) load 3) wing size 4) wheels or not Par example; I know a pilot who could launch at 110kg all up on a sky 26 with a pittance of 27kg thrust. He didn't have a high skill level as he was new, but he was fit and could run for 100m full bore. Since he needed to run so much to get airborne, he didn't fly much, and had a pretty bad taste from his gear making his life so hard and failed launches so common. If he had wheels, he may still be flying it. (motor) If he had a larger wing he may still be flying it. If he weighed a lot less he may be.... you get the idea. The amount you need depends more on wing loading as that takes wing size and all up weight into account. You can fly with much less then you need to launch quickly and therefor safely, rather then running 100m and fatiguing on your face. So, your call in the end how much you need. I like lots. edit: One board member compiled a survey: http://paramotorsurvey.cloudstrategies.co.uk/ Another compiled some results links: viewtopic.php?f=4&t=5111&p=33555 None of them speak to wing loading in relation to thrust. That's a pilot decision.

Am I reading this right? You are doing winch tow releases @ 60ft alt? Even in benign conditions that reads like a scenario for disaster. An experienced tow operator can bring the risk down with an unloaded tow line at release, but it leaves no altitude for error at all. A pilot (yourself) without the benefit of automatic response to surge and experience to use limited altitude for a safe recovery and flare is ill equipped for such tasks. I'm not bashing the learning potential for "low and slow" tows, but there is a cutoff point where the tow leaves the twisted ankle range and requires altitude to become safe again. One handed flying at release is not for pilots that have no time to react before they reach earth again. Here's hoping you (and your school) gets away with it until they change that practice and that they decide to before an avoidable accident forces them to. If they dismiss this avoidable danger, do reconsider their expertise.

@ 1:50 the condor slips right to the runway. Bet the passengers did the when they felt the gear go back up the first time. The second time they meant it. Respect for the skills.

rpm, prop speed, engine output are all part of one equation. When I ordered my motor I specified 3.1:1, but it was shipped with 2.34:1. The result was the prop limited output to 16HP of the 26HP the engine was capable of. While this is great for economy, it limits thrust and therefor climb rate. Some manufacturers build their combinations for longevity, sacrificing some performance in doing so. Owners can reprop to a lower pitched propeller to regain some of the HP hidden in lower rpm limited props, but even so it's a trade off and efficiencies vary simply due to how fast you fly on average (fast/slow trim). I didn't check my redrive prior to first flight, assuming the manufacturer shipped what I asked for. The result was inability to resist sink that would have been easily dealt with otherwise. Thrust curves climb steepest toward the highest end of the rpm range due to the cube law, so whatever limits your rated engine rpm holds you back from using all your engine's power. Some people prefer this for economy, engine longevity and noise. Others feel cheated and dissapointed, and replace redrives, props or both to get all their engines can deliver with a squeeze of the throttle. Deciding which you are may not happen until you have some experience on several combinations to compare, and expect it to change as your skills do. See for yourself: [youtubevideo] [/youtubevideo]

Voltage does not tell the full story of a battery. If you battery is old, has not been fully charged/equalized monthly in storage, is low on water (assuming Lead/acid here and possible sulphation). If you run Nicads, they may have formed internal dendrites limiting amperage output and storage capacity. Nicads have a better chance of being recovered: http://blog.makezine.com/2006/12/18/how ... d-batte-1/ Try a utility battery, or car battery in it's place to test other components with compression load. May be your current battery just never had sufficient giddyup gumption . Tick one vote for a lithium/iron replacement if you need to.