High Airspeed Indications

My plane has recently started indicating about 11 knots high in cruise and also at stall. Reaching under the panel confirms the fittings from the static ports to be tight on the airspeed, altimeter, and VSI. Tomorrow morning the baggage bulkhead is coming off to see if the lines came loose at the static ports. Have any of you had similar indications on your airspeed indicator and if so what did you find to be the problem. Hopefully the airspeed indicator didn't go south on me.

Thanks,

Bryan Wood said:

My plane has recently started indicating about 11 knots high in cruise and also at stall. Reaching under the panel confirms the fittings from the static ports to be tight on the airspeed, altimeter, and VSI. Tomorrow morning the baggage bulkhead is coming off to see if the lines came loose at the static ports. Have any of you had similar indications on your airspeed indicator and if so what did you find to be the problem. Hopefully the airspeed indicator didn't go south on me.

Thanks,

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I had a 4% high indicated airspeed that was due to a static leak. I also noted that indicated altitude varied significantly (120ft) with indicated airspeed.

Everything was OK after replacing the static lines with icemaker tubing and fittings from Lowe's. The original tubing and fittings from the Van's kit (vinyl tubing, I think) had yellowed and cracked between the static ports.

You can check your airspeed indicator on the ground with a homemade manometer. Instruction are on Kevin Horton's site or at iflyez.com, among others.

Yup - I gained about 10 knots one day when a static line popped off behind the panel. Cheapest speed mod I ever saw...

flyeyes said:

The original tubing and fittings from the Van's kit (vinyl tubing, I think) had yellowed and cracked between the static ports.

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You were right on the money. Where the lines from the static ports join and "T" off for the line to the panel the tubing had split and fallen off. Home Depot's Aircraft Isle was closer to the house than Lowe's Aircraft Parts so I went there. (Don't you love flying an Experimental?)Thanks for you help.

Best,