#General
*PC Composites, Machine Sciences, and Boeing have showed interest in donating material/machining. *Trapezoidal fins with a large sweep angle (70 degrees from perpendicular) show a slight advantage over other fin types, based on some preliminary OpenRocket testing.
#PSAS meeting notes
- Getting a freezer for the CF is our immediate bottleneck. LV4 is in charge of this, but there's no reason LV3 can't help. *See Boeing notes about sizes. *There are walk-in freezers in the SRTC. I'll ask about them. *We should ask Machine Sciences if they would be willing to do the machining for the NSR too. (After the stuff for LV3 of course.) *Does the CF need so be stored in an inert atmosphere? *No, according to Sandie, our Boeing contact, it just needs to be vacuum bagged to block moisture and kept in a freezer. *If we're worried about heating in the nose cone, we should look up what temperature epoxy starts to be damaged at. *N-class motors are essentially our design motors. *During the PSAS meeting next week there will be a short introduction to Github... in theory. *Open question for the whole airframe mailing list and LV3: what stability margin caliber is too low? *Stability margin caliber is how far the center of pressure (CP) is behind the center of gravity (CG) in units of rocket diameters.
#Boeing meeting notes
*The Boeing CF comes in widths ranging from 6" to 60". They have 24" wide rolls, which would be ideal. (The PCC rolls are 5 feet?) *If Boeing donates material it will be 8276 (unidirectional) and expired. *"Cat 1" or "Category 1" material is super-primo aerospace grade. *"Cat 3" or "Category 3" material is no longer fit for making planes, but still pretty great. *The prepreg they use isn't tacky at room temperature. *They use tackifier (basically adhesive) to get it to stick to things. Heating it might also work. *They might not have any adhesive sheets to donate, since that's not a thing they really use.
- We need to make a list of the things we want from them, including quantities. *The way material donations from Boeing work is this... They keep a bunch of stock. Sometimes some of it goes unused and expires. Sometimes they order a lot of stuff and their freezers get full. When this stuff happens, they normally just pass it on to the University of Washington. *Because we're not part of this default donation process, we need to periodically ask if there's going to be a donation cycle soon. Leslie has volunteered to do this. *There might be future seminars on CF, composites, and material science.