Re: [PSAS] Weather advisory, Tuesday 11-Jan-2011 meeting canceled?
On 01/11/2011 06:13 PM, Glenn LeBrasseur wrote: I just talked to Andrew (6 pm) and he thinks the weather is bad enough to cancel tonight's meeting. I'm in SE Portland right now and there is freezing rain coming down, and it seems to be sticking on the road. Temperature is 30 deg F here. It certainly could get bad enough. I'm net control for KD7ZDO at the moment, Clackamas ARES, we're running a weather reporting net (I'm running it from my home station - listen to 147.12 to hear me, or 147.32 for all NW Oregon/District 1). It seems to be getting colder with light precip everywhere. Near the gorge people are getting some icing. Cheers, James KN1X -- James Perkins ja...@loowit.net KN1X www.loowit.net/~james 28950 S Girard Rd, Colton, OR 97017+1.971.344.3969 mobile ___ psas-team mailing list psas-team@lists.psas.pdx.edu http://lists.psas.pdx.edu/mailman/listinfo/psas-team This list's membership is automatically generated from the memberships of the psas-airframe, psas-avionics, and psas-general mail lists. Visit http://lists.psas.pdx.edu to individually subscribe/unsubscribe yourself from these lists.
Re: [PSAS] Weather advisory, Tuesday 11-Jan-2011 meeting canceled?
On 01/11/2011 07:11 PM, Benjamin Kaplin wrote: Well, those of us willing to brave the conditions will be here - and some in fact are already! There is still a winter advisory, but it appears most of the moisture moved through. The NWS doesn't have anything more to collect from the the ham weather spotters and we've closed our nets. I'd be watchful for slick patches here and there, especially just W of the Columbia Gorge, but I don't expect there to be a skating rink on the roads tonight. Cheers, James It certainly could get bad enough. I'm net control for KD7ZDO at the moment, Clackamas ARES, we're running a weather reporting net (I'm running it from my home station - listen to 147.12 to hear me, or 147.32 for all NW Oregon/District 1). It seems to be getting colder with light precip everywhere. Near the gorge people are getting some icing. Cheers, James KN1X -- James Perkins ja...@loowit.net mailto:ja...@loowit.net KN1X www.loowit.net/~james http://www.loowit.net/~james 28950 S Girard Rd, Colton, OR 97017+1.971.344.3969 mobile ___ psas-team mailing list psas-team@lists.psas.pdx.edu mailto:psas-team@lists.psas.pdx.edu http://lists.psas.pdx.edu/mailman/listinfo/psas-team This list's membership is automatically generated from the memberships of the psas-airframe, psas-avionics, and psas-general mail lists. Visit http://lists.psas.pdx.edu to individually subscribe/unsubscribe yourself from these lists. ___ psas-team mailing list psas-team@lists.psas.pdx.edu http://lists.psas.pdx.edu/mailman/listinfo/psas-team This list's membership is automatically generated from the memberships of the psas-airframe, psas-avionics, and psas-general mail lists. Visit http://lists.psas.pdx.edu to individually subscribe/unsubscribe yourself from these lists. -- James Perkins ja...@loowit.net KN1X www.loowit.net/~james 28950 S Girard Rd, Colton, OR 97017+1.971.344.3969 mobile ___ psas-team mailing list psas-team@lists.psas.pdx.edu http://lists.psas.pdx.edu/mailman/listinfo/psas-team This list's membership is automatically generated from the memberships of the psas-airframe, psas-avionics, and psas-general mail lists. Visit http://lists.psas.pdx.edu to individually subscribe/unsubscribe yourself from these lists.
Re: [PSAS] Sony-sponsored student rocket project
On 08/02/2010 11:13 AM, I wrote: Learning from the failures of others, what can we gain from this? * On clusters, design the ignition to minimize the chance that two motors can ignite, yanking the ignitors out of the third motor (perhaps make the rocket light it's own ignitors?). I wonder if they would share their ignitor setup so we can learn something from them. Hm. One part of this is physical contact between the solid rocket fuel and the ignitor (being pulled out before ignition). You could help with that by physically binding the ignitor's cabling to the rocket, but then if you still needed milliseconds more contact to ignite, while the rocket is under motion, you really *do* need the ignition power source, current switch, and cabling to all live on the rocket or be on a long wire. I wonder if you only need positive ignition response for a short time before it loses value. Perhaps if the ignition components were external to the rocket and on a 20m cord or launch rail interlock where it gets disarmed/ falls off once the rocket clears the launch tower, then you can avoid a motor firing up well into flight. Maybe a long ignition wire is best. *Make sure the conrol is capable of nulling out the yaw caused by a motor failure. I have little mechanical engineering background, but aerodynamic forces and likely bending of components, freezing of separation surfaces when things are misaligned make this another interesting discussion for which it may be difficult to design a viable solution. I had another idea: In the case of a major failure of an earlier stage, consider design of mechanisms by which subsequent stages may be separated and have a reasonable expectation they may be safely recovered. (Imagine if we still had the avionics from LV2b) OK, I can hear the mechanical people say 'what, you want it unbreakable and boostable under 25G and shaking up to 25G but have it separable and independently recoverable?'. Well, it should make for an interesting discussion. James ___ psas-team mailing list psas-team@lists.psas.pdx.edu http://lists.psas.pdx.edu/mailman/listinfo/psas-team This list's membership is automatically generated from the memberships of the psas-airframe, psas-avionics, and psas-general mail lists. Visit http://lists.psas.pdx.edu to individually subscribe/unsubscribe yourself from these lists.
