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No Airspeed and altitude

FinnFlyer

Well Known Member
Had an interesting flight this early evening.

Due to wildlife (deer, turkeys and other birds) I keep my eyes outside during takeoff.

When above tree level I looked at ASI. Zero!

Then a look at altitude. None.

This was my second flight with a 60 lbs concrete bag in the baggage area, so feel was still a bit unfamiliar. Fortunately I had GPS speed and altitude.

By the time I was ready to land, herds of deer had decided to start grazing on the runway. Coming in for touchdown they stood there just looking at me.

Fortunately I didn't come in all that hot and was able to slow down and avoid the deer.

Inspection of static ports revealed that both were clogged. I had no idea that mud daubers (or whatever they were) were able to get into such tiny holes and block them with their mud.

I though that a static bypass valve in the cockpit were only for IFR (icing). Now I'm considering adding at least a Tee with a plug in the static line.

Meanwhile I'm adding inspection of static ports to my preflight routine.

Finn
 
Steinair has a nice alternate static valve that looks like a standard toggle switch. Easy to install and works well!
 
Their are indeed mud daubers of all appropriate sizes to fit and fill all openings of any size that would problematic once stoped up on any aircraft and most other machines too :eek:
 
Interesting that ASI was zero. Was pitot also blocked?

Hmm ... actually had Dynon D-100 show something like 169 mph on final approach, AOA tone blaring. I guess it got confused.

But seem to remember near zero airspeed during take-off. Could be wrong. And then later picked up a bit. When at a few thousand feet, the altimeter did show a few hundred feet.

But during flight the D-100 showed "GPS assist" and GPS speed in purple.

No, didn't find any pitot blockage. Have zip ties in pitot and fuel vents when parked.

I agree airspeed was odd and I should have paid more attention.

Finn
 
Have you had any training for landing without asi? I was fortunate enough to have an instructor that made me do it before I soloed. It’s actually pretty easy. I could uncover the asi on short final and be bang on speed. It certainly gives one confidence.
 
Have you had any training for landing without asi? I was fortunate enough to have an instructor that made me do it before I soloed. It’s actually pretty easy. I could uncover the asi on short final and be bang on speed. It certainly gives one confidence.

Well, not my first time. Have forgot pitot cover a few times.

But my first time with no altitude (other than GPS).

And yes, not too difficult. Get a feel for stick forces. But was first or second time with 100 lbs in the baggage compartment, which does change stick forces significantly.

Finn
 
Remember that you still have your power settings. When you fly approaches, etc., take note of various RPM settings vs. indicated airspeed just in case you need to fly power and not airspeed. Altitude-wise, you should know where you were and should be able to use your VSI to determine the descent or climb rate to the next altitude, e.g., 500ft/min, etc. Scan remaining instruments for trends and stop them before they exacerbate such as turn and bank, skid (ball), and RPM. If VFR, you're in good shape as you have the horizon.

Steve
 
Remember that you still have your power settings. When you fly approaches, etc., take note of various RPM settings vs. indicated airspeed just in case you need to fly power and not airspeed. Altitude-wise, you should know where you were and should be able to use your VSI to determine the descent or climb rate to the next altitude, e.g., 500ft/min, etc. Scan remaining instruments for trends and stop them before they exacerbate such as turn and bank, skid (ball), and RPM. If VFR, you're in good shape as you have the horizon.

Steve

VSI is using static ports.

Finn
 
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