Airbox?

[Taltruda]

What does the airbox look like on a rocket? I would love to have a forward “rocket style” smiley face on my -4, although I probably don’t have the room.. pic for attention

 

[Aden Rich]

On the HRII inlet (smiley) under the spinner, there is NO airbox. It mates up to a wye inlet that is bolted to the front of the the forward facing fuel servo. So on the end of the smiley, its going from the smile to like a 3" inch round outlet. Then the smiley outlet mates up to the inlet on one side of the wye (the straight part) The wye has an alternate air valve in there that can be closed and you can pull from the other inlet if the smile was to be blocked up. Problem with that set up is that second inlet is always open so any RAM air is lost as the engine is only pulling in air as needed instead of air being "forced" into the servo inlet like a poor man's turbo charger.

 

[Ironflight]

In the F1, the Airbox is part of the removable cowl inlet - somethign that is turning out to be incredibly handy. Nine Skybolt fasteners take ten seconds to unlock, the scoop comes off to reveal the entire FI Servo, alternator, starter, and pretty much 90% of the things you want to check under the cowl when looking for problems. The flat rectangular air filter sits horizontally in a carrier so the air come sin the smiley scoop, passes UP through the filter, is collected in a plenum and goes back a 3-1’2” outlet fromt eh plenum into a short SCAT tube connected to the horizontal servo inlet. I of course, have 1800 pictures from my build, none of which are organized other than chronologically right now, so here is a picture with the scoop removed after the first flight (checking for leaks):