Pitot tube

HomeBuiltAirplanes.com

Help Support HomeBuiltAirplanes.com:

WindHorseRookie

Well-Known Member
Joined
Aug 24, 2020
Messages
54
Location
Oakwood Va.
Hello all,

I have a question about a pitot tube, I have one that has a very small hole in the tip end. It is made by Dwyer, single tube , single small hole. Is there a reason for this?

2nd question,
I installed a separate ASI to test because I bought it used, it is kind of “bouncy” the needle seems to bounce around some. What might cause this?
the tube is 1/4” plastic with a full diameter open 1/4” SS tube on the end.
my original is the same setup only the tube is aluminum.
 

Dana

Super Moderator
Staff member
Joined
Apr 3, 2007
Messages
9,744
Location
CT, USA
What you have is made for measuring low velocity airspeed in ducts and such, it's not an aircraft pitot tube. If the hole is "very small" as you say the ASI will probably have too much lag in the indication. Typically the pitot tube is about the same diameter as the tubing going back to the instrument, usually 1/4".

If the instrument is "bouncy" it could be that some of the gears or bearings inside are worn. I had an altimeter like that.
 

Aesquire

Well-Known Member
Joined
Jul 28, 2014
Messages
2,612
Location
Rochester, NY, USA
It's possible it's old sorta aviation stuff. I had a Dwyer Wind meter long ago, they still make them. Their stuff gets marketed to boat folk, and beach/surf/kite/... on to hang gliders, ultralights, aviation.

I suspect repurposed industrial or boating origins.

Some stuff everyone uses, because it works. Little line cleats, for example. In sailboats, power kites, paragliders, you need a gizmo that can shorten a line, which is a high strength synthetic, small, smooth, ( so as not to catch on lines & you ) light, corrosion resistant, etc. So everyone uses pretty much copies of wee alloy/plastic slider things.
 
Top