A colleague at work , and ex-RAF Technician, Pete Bush gave me an article about calibrating an ASI using the pressure from dipping a hose at different depths in a clear container.
Euipment: Old coke bottle with top cut off Food colouring (optional) 1/4" ID clear pastic hose (to fit standard Vans pitot) Aluminium pipe or similar to keep hose straight in bottle Ruler in inches Spread sheet Download here
The spreadsheet contains instructions and as you can see from the second photo it works up to 90 kts. If you want more speed you will need a taller clear vessel. It also checks for leaks.
I love simple things like this. Thanks Pete
Post Note I adapted a Pressure Error Correction spreadsheet and used that for an airborne calibration which showed my ASI was overeading by about 4.5%. I used the Vans aluminium pitot and the standard static port rivet and location. Not an issue as I know what the value is and it's pretty small.
