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First - fly the airplane...

airguy

Unrepentant fanboy
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Had an interesting moment yesterday, I lost my airspeed indication on rotation off the runway. With 2600' of runway and wires on the end, it was a "keep going" situation.

This is when knowing the airplane really pays dividends. I know full power solo with full tanks will give me 2000'/min climb, so I just held about 1000'/min and knew I would be good. I leveled off and set 2500 rpm and 17" MAP which will always give me 100 knots, and came back around to a long final. Pulled all the power and dumped 20 degrees of flaps and stuffed the nose down to the same angle I use every time, and it worked this time just like every other, from my flare and float I'm guessing I was maybe 10 knots fast over the threshold. Turned out to be a non-event.

I chased the problem down to a broken TEE fitting where my pitot line splits behind the panel to feed my backup EFIS with airspeed data. This particular fitting came from the aviation department at Lowes Hardware, and after 135 flight hours it decided it had served its sentence and gave up.

Anyway - the upshot of all this - practice some slow flight occasionally without airspeed info, or just turn off the EFIS entirely and play with it. Learn how it feels and sounds, you never know when that experience and time spent will pay dividends.
 
Once lost my altimeter flying a rented Citabria. Asked the tower if they had my altitude; they did not. Oh well, I thought... guess I'm going by feel on this one, and it was no problem. During the decades of dreaming of owning my own airplane, one of the things I'm most keenly anticipating is getting the feel of my own personal aircraft; wearing it and understanding it's behavior intimately. Won't be too much longer...
 
Had an interesting moment yesterday, I lost my airspeed indication on rotation off the runway. With 2600' of runway and wires on the end, it was a "keep going" situation.

This is when knowing the airplane really pays dividends. I know full power solo with full tanks will give me 2000'/min climb, so I just held about 1000'/min and knew I would be good. I leveled off and set 2500 rpm and 17" MAP which will always give me 100 knots, and came back around to a long final. Pulled all the power and dumped 20 degrees of flaps and stuffed the nose down to the same angle I use every time, and it worked this time just like every other, from my flare and float I'm guessing I was maybe 10 knots fast over the threshold. Turned out to be a non-event.

I chased the problem down to a broken TEE fitting where my pitot line splits behind the panel to feed my backup EFIS with airspeed data. This particular fitting came from the aviation department at Lowes Hardware, and after 135 flight hours it decided it had served its sentence and gave up.

Anyway - the upshot of all this - practice some slow flight occasionally without airspeed info, or just turn off the EFIS entirely and play with it. Learn how it feels and sounds, you never know when that experience and time spent will pay dividends.

Did you figure out why the fitting failed?
 
Did you figure out why the fitting failed?

It cracked in the body of the fitting, did not separate but was leaking significantly enough that the airflow coming in from the pitot tube was only sufficient to show 30-40 knots. This was the white PVC push-in type that is typically used for 1/4" water line for a fridge or icemaker.

Come to think of it, I had one of these fail several months ago, on my icemaker... maybe they've just got it out for me...
 
I run Avare on my android phone. It gives me a good ground speed and fair altitude backup. Better than nothing and dirt cheap!
 
GPS is a pretty good check if you know the approximate wind and direction. I always crosscheck mine on final in case the ASI took some sort of dump.
 
What did your backup EFIS show without pitot pressure? I mean what attitude?

I've got Skyview for primary and Garmin G5 for my backup EFIS, the airspeed on both of them matched but was in the 25-40 knot range the whole time. That was my first clue as to the nature of the failure - two independent sensors showed identical results, so I knew it had to be a legitimate pressure problem somewhere between the pitot inlet and the devices. My initial assumption was a bug in the pitot tube, that happens and it's the easiest/simplest to check and fix. I pulled the pitot and blew it clean, reinstalled, and went to the runway and powered up. I got fast enough to lift the nosewheel off without any indication at all on the airspeed so pulled power off and went back to the hangar, where I pulled everything apart and finally found the Tee fitting that was cracked.

Both EFIS were indicating correctly for attitude. I know Skyview has a "GPS-assist" mode that it uses if the airspeed indication is suspect or missing, I guess the Garmin G5 does also because it was a good attitude on the display.
 
Had an interesting moment yesterday, I lost my airspeed indication on rotation off the runway. With 2600' of runway and wires on the end, it was a "keep going" situation.

Why couldn't you use your GPS ground speed?
 
Good job Greg

For all of us, if you can't fly your plane safely in a VFR pattern by just sound and engine settings, you NEED to practice. This is just basic airmanship 101 in light planes.

I'm ready with the flame suit, but we should all be comfortable if these little airplanes with just the basics.
 
Had a similar event with my RV-4. No airspeed on takeoff. Went high and did a few stalls just to remind myself what it felt like. Also came in ~10 knots fast. Turned out some little critter thought the pitot tube looked like home.
 
Way back at the end of the 90's my high school buddy airline captain/flight instructor came out and flew with me to get me current after a 13 year hiatus. During one of the refresher flights he covered my airspeed indicator with a piece of paper. I managed to perform a day of pattern work no problems that day. It was a huge confidence builder.
 
I agree with you totally Jerry.
We Are a large group of diverted flyers but some times over complicate matters. Yes learn to fly the aircraft using outside visual items like a horizon. We have so many pilots glued to the instrument panel. I see this all the time doing biennials.
 
While descending in a gap in broken clouds, the Dynon D10A (only airspeed indicator in the panel) horizon rolled completely up-side-down before slowly erecting. But the airspeed was reading at least 50 kts low.

But the flight was completed with no stress because of the non-electric LRI indicator (angle of attack) which is my primary flight instrument even when landing with everything working properly. Slow down on downwind until the LRI needle comes alive, then fly the pattern while decelerating until the needle is white/green over the numbers. Smooth landing. :)

I found an insect wing neatly covering the pitot tube, the wing had enough porosity to allow some ram air but not enough to keep the Dynon happy. This is one reason I like having the totally independent LRI in the panel. It is equally useful during takeoffs.
 
To be perfectly honest, if you can't land your airplane without ANY kind of instrumentation, you shouldn't be flying it!
 
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I cheat. I have an AoA system. I could easily land with that alone.

I've got the Dynon AOA also - but it lost its mind when I lost the pitot pressure because it compares the AOA pressure to the pitot pressure. One was normal while the other went offscale low, and the AOA was screaming at me for about 5 seconds thinking I was in a deep stall, until the Skyview recognized the airspeed was faulty and switched to GPS Assist mode. With that, you don't have an AOA on the display.
 
Good piloting Greg.
I have had a couple of "fly the airplane or die"
moments myself. Still here, thanks to some very good flight training.
 
For all of us, if you can't fly your plane safely in a VFR pattern by just sound and engine settings, you NEED to practice. This is just basic airmanship 101 in light planes.

I'm ready with the flame suit, but we should all be comfortable if these little airplanes with just the basics.

Better yet, go fly for 15 minutes at minimum airspeed and learn to feel what the wing is telling you.
 
For all of us, if you can't fly your plane safely in a VFR pattern by just sound and engine settings, you NEED to practice. This is just basic airmanship 101 in light planes.

I'm ready with the flame suit, but we should all be comfortable if these little airplanes with just the basics.

Think of the children!
 
Fly the plane

I have to agree. My instructors forced me to fly the plane without the instruments. Had me looking out the window and listening. It also helps if you are landing at the same field that you have also landed at 50 plus times.
Darrell
 
Good flying Greg.

Stuff happens and we find ourselves in new territory.

Fly the airplane is always best first thing to do.

I found GPS ground speed good aid last time I had no ASI. (forgot to remove pitot cover) Just add or subtract estimated wind and it is real close.
 
...

Anyway - the upshot of all this - practice some slow flight occasionally without airspeed info, or just turn off the EFIS entirely and play with it. Learn how it feels and sounds, you never know when that experience and time spent will pay dividends.

Good advice Greg. I had my pitot tube inop on several occasions (cover, ice, a bee). It gets your attention for sure.
 
I had a similar situation leaving Oshkosh--when there were planes everywhere. I had recently flown with the BEST CFI I have ever known, and he had showed me a trick. He told me to draw a blue dot on my fingertip, a really big, heavy dot. At cruise, he told me to reach out and touch the horizon straight in front of me. It left a blue smudge on the windscreen.

Then he covered the airspeed indicator. He would have me raise the dot a certain distance, and he would tell me the airspeed. He was always right on! I have tried it in other airplanes (I was in my 9A the first time) and it works every time.

Bob
 
For all of us, if you can't fly your plane safely in a VFR pattern by just sound and engine settings, you NEED to practice. This is just basic airmanship 101 in light planes.

Completely agreed. As a long time Cub and open cockpit ultralight pilot, airspeed indicator failure in VFR should be a non event. Now if your butt sensor fails... you've got problems.
 
I forgot my pitot cover on a walkaround one day, and ended up taking off with it. Noticed just after my wheels left the ground that my airspeed wasn't moving. Oh well... Keep going. I did have my Aera GPS on the panel, so I had groundspeed to reference, so I just flew a circuit and landed with it, adding the windspeed roughly in my head.

Afterwards I realised I spent more time checking my groundspeed during the circuit and wondering how well I would maintain the "right" speed on final, than I actually did on short final and landing... I just flew the plane and didn't check speeds because it felt like every other landing.
 
Me too Snowflake. Seems like forgetting pitot covers, chocks, etc. only happens to me when I'm taking up a nervous passenger for their first ride in an experimental. Guess I should worry more about the plane and less about the passenger. Keeps you humble. John
 
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