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Quote:

Originally Posted by georgegassaway

I did an R/C R/G for the night launch at NARAM-51 (10 years ago). It used a number of super-bright individual LED's. Some were "flashlight beam" types, shining horizontally onto the top of the wing panels, and also on the wingtips and nose pointed forward to light up the ground ahead of it during landing. I didn't know much about "Strip" LED's before (they certainly would use up a lot more battery current than the LED's I did use). A lot of info and pics beginning here:

https://tinyurl.com/y5mh2twe

Before liftoff:

Almost all of the illumination is by the model's LED's

Video of the last minute of glide, by Chris Taylor:
https://www.youtube.com/watch?v=jvu3iZA2vow

If I did it again, I'd use strip LED's along the fuselage sides and in a few strategic places. But not across the wingspan due to the disruption of the airflow over the wing, not only would performance be hurt really badly but the handling and trim would suck terribly.

I'd use the same kind of super-bright LED's as before for the rest of it. To do LED strips inside the wing would either require building in or cutting out a shallow channel for the strips, then covering them over with something transparent. Or building an open-bay balsa wing covered by something like Monokote, which I'm not keen to do again (much less for rocket boosted gliders). My last open-bay balsa wing was a sailplane (my own design) over 25 years ago.

BTW - I used two batteries onboard. One for most of the lighting. The other for the receiver and just enough secondary lighting to try to fly it back if the primary lighting went out. I figured the primary battery would go dead before the receiver and secondary lighting battery went dead. Never had that happen. I would also repeat that double battery strategy if I did it again.

Unfortunately the model was destroyed a few years later, used a Quest D5 which took off too slow. It pitched down and crashed before getting enough airspeed to be controllable. Normally used a reloadable D7 or E6.

Ouch...having seen the Chinese-made Quest C6 motors' under-performance (they might have had the correct ^total^ impulse, but their average thrust was more like that of a C4--I had a couple of cliff-hanger flights on those, after which I only flew them in lighter rockets), I was always leery of their black powder D motor.

Thank you for posting these still and motion pictures! Your wing "sign illumination" worked very well, like the night-time vertical stabilizer lighting on jetliners. To give a Douglas Trumbull-esque, ghostly "Close Encounters" halo lighting effect, strip LEDs could be "investment cast" into an expanding foam fuselage, perhaps a millimeter or two below the outer surface (there are "How-To" YouTube videos on molding model airplane wings and other parts using regular hardware store-type expanding foam, the kind that comes in aerosol cans fitted with plastic tubing hoses). Or:

For a model with a built-up or box-type fuselage (with aerodynamic fairings applied), the LED strips could be pressed into strips of structural foam, which would be trimmed to form the fairings (the LEDs' bezels would be ^just^ under the fairing surface, to keep them from producing drag). Built-up (tissue-covered balsa framework) fuselages would also give a bright, eerie effect; I once read an older man's account of having flown, as a boy in the 1940s, a white tissue-covered Wakefield-type rubber-powered airplane with a flashlight bulb & battery in the fuselage. The police ran him out of the local park, after people complained about a formless, glowing white "thing" flitting back and forth in the dark...:-)