Thoughts on cabin ventilation

[Dorsal]

Looking for advice on cabin venting, I have vista vents which I am leery of putting in my bubble doors. Van's has a $60 kit with two naca inlets and a couple of eyeball vents which looks interesting.
Ideas, comments suggestions?

[Dave S]

Dorsal,

I know of several folks who have used the vista vents on a kitfox; and, on other aircraft. They are happy with them

I puzzled over what I wanted to do for vents also. I believe my initial inspiration/motivation was taking off on the first flight in 89 degree weather with no vents and no shutoff valve on the heater line. Oh well.

We fabricated some rectangular cowl vents for N128DD rather soon after the first flight - not too different than the ones which can be purchased for an RV. End result was good - they provide all the fresh air on each side of the aircraft you need, the flow can be regulated; and, they fit flush when closed and seal so there is no extra pneumonia hole when the OAT is below zero.

BTW - two thoughts factored into not using the vista vents (although everyone who has them say they work well) 1 - didn't want to cut a hole in the window. 2) didn't want to have anything on the window for the sake of unobstructed vision.

I'll plan on snapping a couple photos to send you the next time I get out to the 'port.

Sincerely,

Dave S
St Paul Minnesnowta
Kitfox 7 Trigear
912ULS Warp drive

[Dorsal]

Dave,
Thanks, pictures would be great

[RandyL]

I plan to put NACA ducts in each kick panel just above where the map pocket is and connect them to eyeball vents, either directly or routed via scat tube to eyeball vents in the panel. I know the Kitfox S-LSA is being built this way and I think the McBean's will be introducing such a kit. I too would prefer not to go the Vista vent approach... too much drag. ;-)

[hansedj]

We just put naca's on the cowl, they open and close got them at aircraft spruce 2 years ago but I can not find them in the catalog now. posting pictures of inside and outside.

[Skybolt]

I don't have NACA vents cut into my side panels, so I have no comparison there. But the Vista vents that I placed into the door windows work very well and are easy to istall. As Dee said;
...no obsructions (I never notice they are there unless I want to use them).
...very good directional control (can blow cool air to hands and then move to face [this is good in the Atlanta summer] or turn open slightly for ventilation.

I think I would be unhappy with the NACA vents at the low cowl position and if I used scat tubes and eyeball contols, I don't think I would get the amount of cool air that comes from the Vista.

Eric.

[Dave S]

Dorsal,

Finally got some photos of the cowl mounted cabin vents on our kitfox. See attached. These are home-fabricated and designed sort of like the RV cowl vents. Pardon the lack of final paint finish.

The reason for the larger gap on the rear of the vent is to provide adequate relief on this edge because of the hinge swing. The last photo is rotated 90 degrees - the vents open at the front into the airstream. There is one on each side of the cowl. The size of the hole is 2" wide X 3" high. Friction of the bolts/washers is sufficient to hold them where they are set and to allow complete range of movement.

I will likely add some sort of screen for the openings in the future - a 100 MPG june bug came through the vent and splattered all over the inside once.

Sincerely

Dave S

[Dorsal]

Bad day for the bug!
I like the design and I think this is the direction I will go, anything you would do differently now that you have completed them?
Thanks for taking the time to post these pictures.

[Bryan]

I use the NASA vents in the kick panels and have had no problems. I usually leave my door open while taxiing and then shut it as I get ready to depart. As soon as I land I usually open the door back up for taxiing. With that said I really believe the system that Vans uses, that has an eyeball so that you can aim the blast of air where you want it would be better.

[Dave S]

Dorsal,

The size worked out right - wouldn't change that. Thought about having a cable to operate the vent but decided against that to avoid extra stuff. It is a little bit of a pain to work out the geometry of the lever - but that is unavoidable with this particular design - used up a few pieces of 100# pattern paper before cutting up aluminum anyway. Having a short lever that is out of the way of my knee worked out just fine - lever goes forward to open on this one.

Dave S