I had a Cox .049 Black Widow engine many years ago, which I mounted to a home-built balsa wood U-control model airplane. That engine was great..started easily and ran well really screamed. It seemed a definite step up from the standard .049 engines usually mounted on the 'ready to fly' plastic U-control model airplanes of the day. The only problem for me was the rather large fuel capacity and long run time..I found myself getting motion sickness waiting for the thing to run out of fuel.

Ive always liked the black widow, one of the best cox engines , they always glow brightly when running well

@coolengineguy The glow you are seeing is the reflection of the glow head element! This Black Widow has the open exhaust ports that give you a clear view of the piston. Plus most of the time, I'm only like 3-4 inches away from the engine. Like I said this glow head is one of my brightest glow heads, plus its quite new it was only used a few times.

Yea..I always say the devil have nasty red eyes ha,ha..great video.I saw it the first time also in garden house,close door,with my COX P-51 mustang test run....I say...what the F@ck???. Its a nice view.I have some cox engines too.. from peewee to also the 15 madalion 2,5 cc. I buy it in a box full of engines,it was a surprice buy! .cant wait to here hem run...big brotha :-) ...Also cox engine with diesel head doing fine,..start easy as glow! keep them singing!

@rastus10 It could be that too. The video is not that clear but you can see the reflection of the glowing filament coil on the top of the piston. It does glow a lot brighter once it is started. I rarely run 35% nitro in my engines as it shortens the head life and it just plain wears it out faster. I only had 35% at the moment so that is why I used it.

@coolengineguy You should run one of these engines at night and watch it glow! If you look at it right, you can see that is really the glow head element glowing. This is one of the brightest heads I have, when you connect the glow head clip to the head, you can really see it glowing! Yeah, using the 35% nitro fuel was like running Cox racing fuel through it but the engine still glows bright even when its ran off 5% nitro. No the piston was not red hot, it was a reflection from something.

You think the filament is that bright? I would guess we see combustion fire from the nitromethane and methanol. Ever seen a dragster at night.? That ain't the sparkplug light. As much noise as it gives off I think it would be creating enough energy to way outshine the glowplug. I could be wrong. Maybe it could be tested by watching the glow with varying amounts of the two volatiles in the fuel. Only one at a time because it's mostly the methanol catalyzing the platinum to glow.