I am considering a tail mounted NACA scoop in the tail of my Legacy (will still have the factory vents running to panel mounted eyeball vents). Noise reduction is my primary reason for considering this. I modified my stock located 360 cabin vents (reshaped the inlets and redid the plenum) so they flow decent on the ground, very well in climb, and blast away at high speed cruise. However, as Scott Kreuger and others have pointed out, they are very noisy, materially increasing the cockpit noise level. The option of the extra flow of more vents would be a further plus.
I am looking at the ACS NACA vent 902 MA-A that has an opening of 5.5" x 2.5" with a 2" diameter outlet. I would run this to a small overhead console that I am building to hold map and dome lights.
Has anyone done this on the Legacy? I would appreciate any thoughts on how effective the noise reduction might. Also, any tthoughts on where the best location for the NACA vent might be? I would think the pilot's side would be less susceptible to taking in exhaust (I noticed that an oil leak on my 360 wrapped around up the copilot's side of the rudder.
Clark Baker
LNC2 360- 950hrs
L2K in progress
>>>----- Original Message ----- From: "Roger Iverin" <
roger@iverin.com>
To: <
lml@lancaironline.net>
Sent: Saturday, July 26, 2008 5:30 AM
Subject: [LML] Your best modification/upgrade etc.
My best Mod, the one I most appreciated was the NACA air duct installed in the vertical stab together with an air plenum with a low end with a water drain in the vertical stab and rear tail cone area. I then installed a half tube formed from a split pvc pipe about 4 inches OD affixed on the top underside of the fuselage forward along the fuselage seam which was duct taped and a one bid fiberglass layup applied which became the permanent air tube forward. I then constructed an air box just behind the fuselage rollover bar imediately behind the canopy and above the seat back. <<<<