Just as a datapoint... Some experimental guys have a NACA vent on the flat underside of the wing, they seem to work extremely well. So it's not just where you place the vent, but also the shape which helps.

I was paying some attention to my airflow when I was out flying this morning. I don't know if I'm just lucky, but I seem to have almost as good of flow as I had prior to the Sportsman install. It might be slightly lower, but it's still blowing pretty good out of the vents in cruise.

How about making a small scoop that can be glued in place at the bottom of the opening. Along with closing off the internal box to ram the air more directly into the original opening...

Thinking out loud here..

Brian

So is it really only Gunny and I that are suffering from PSLF (post stol low flow)??? Brian I wish I was close by to have you tinker with a solution!

My wing root vents seem to work great (I have Sportsman cuff and 4-inch bubble windows) but then my door and window seals leave a lot of opportunity for air to leak out. Perhaps your cabin is sealed too well. See what happens to the vent air flow if you crack a window in flight.

My vents work fine also with the Sportsman. The mechanic who installed it put some extra rtv silicone in the hole to funnel in the air

I haven't noticed a change in airflow from the vents on my plane either after installing the Sportsmans STOL. I have a 172K and couldn't be happier with the addition of the kit. My bird has some pretty old seals around the doors and window though. Not sure if this would make much difference, but maybe it does. With the way the plane leaps off the ground at 45 MPH on takeoff, I think I'd still be happy even if my vent didn't work as well.

Do you have an updated review on the Sportsman STOL installation on your plane now that you have more time flying it Oregon180?

Scolopax wrote:Do you have an updated review on the Sportsman STOL installation on your plane now that you have more time flying it Oregon180?

I love it! I do land shorter, for sure, but for me the takeoff improvements are the bigger deal. I've flown it quite a bit heavy and have less time so far in it light. It really does wake the wing up.

The only time the stock wing would be preferable would be in turbulence, or gusty, swirly winds. You'll feel the bumps a bit more, and it'll be a little bit more of a handful in gusty winds, but it's nothing major.

Now I just need some big tires!

Has anyone else noticed their ASI reading 10-15mph low as compared to the GPS speed?
Prior to the Sportsman the ASI and GPS were in pretty good agreement which was useful in determining wind speed and direction when landing. After sportsman it's less so.
And btw my airflow through the vents is as good as before.

Excellent! I really enjoyed the improvements on my old plane. Installing it on my current C180 this winter. Looking forward to it.

AKclimber wrote:Has anyone else noticed their ASI reading 10-15mph low as compared to the GPS speed?
Prior to the Sportsman the ASI and GPS were in pretty good agreement which was useful in determining wind speed and direction when landing. After sportsman it's less so.
And btw my airflow through the vents is as good as before.

The angle of your pitot tube could be off maybe? I didn't notice any difference after installation.

I wasn't sure if others needed to adjust the angle of their pitot tube after sportsman. I have the heated pitot tube. Of course I could have just coincidentally sucked some bugs in there....

AKclimber wrote:I wasn't sure if others needed to adjust the angle of their pitot tube after sportsman. I have the heated pitot tube. Of course I could have just coincidentally sucked some bugs in there....

I have a horton on my 180, and it seems to read about 10-15mph slow at anything over 100mph. Not sure if its because of the stol kit or some other issue.

I will report on my most recent attempt to fix my post stol low flow (PSLF) problem. As I reported earlier, my vent airflow was extremely anemic following my sportsman cuff install. Interestingly I was getting much more air flow on climb out (higher angle of attack) than at a low angle of attack, but much higher airspeed, at cruise. Willie at Steen scared me into not enlarging the whole toward the top of the wing, and I have checked my opening to the supplied template several times and it is right on the money. A few weeks ago I put some 1.5" flexible tubing between the new leading edge and old leading edge intake, leaving a little tubing protruding in a scoop like fashion on the lower edge. This has helped the flow somewhat, but it is still not nearly as good my airflow prior. Any other suggestions? Do I dare extend the intake toward the top of the wing?

I know its probably not helpful at all to you... but I've done two Sportsman installs now (170B and the 180) and have had no issues w/ airflow. On both A/C, the top of my vent hole was at the upper template mark, and the bottom goes down flush with the foam.

ID172inCO wrote:I haven't noticed a change in airflow from the vents on my plane either after installing the Sportsmans STOL. I have a 172K and couldn't be happier with the addition of the kit. My bird has some pretty old seals around the doors and window though. Not sure if this would make much difference, but maybe it does. With the way the plane leaps off the ground at 45 MPH on takeoff, I think I'd still be happy even if my vent didn't work as well.

I noticed a little" singing "sound in air vents after adding the SPORTSMAN leading edge .

I have good airflow in my vents, perhaps ever so slightly less, but still plenty enough to blow maps around. My pilot side vent has a bit of a whistle as well during cruise, glad I'm not the only one.

Overall, this is such a marvelous mod.

Good news I found the solution, bad news it is expensive.
$450 expensive.

http://www.sportys.com/pilotShop/product/9578

Flow increased like 3 times, plus I can direct it anywhere I want, Costa Rica is hot, to me it is worth it, plus they look real good.
Totally solved my problem.

motoadve wrote:Good news I found the solution, bad news it is expensive.
$450 expensive.

http://www.sportys.com/pilotShop/product/9578

Flow increased like 3 times, plus I can direct it anywhere I want, Costa Rica is hot, to me it is worth it, plus they look real good.
Totally solved my problem.

I want to get some of these for our 185. We still have the stock "beer can" vents...