You are flying along and your airspeed indicator fails

SixPapaCharlie

SixPapaCharlie

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You are at altitude 20 min from your destination (uncontrolled 4k ft runway) and it is Texas so one of those rogue plastic grocery bags has caught some lift and managed to get snagged on your pitot tube.

Curious about the different answers.
I know there are pilots that can feel their way to the ground but it is not something that is specifically taught.

Clearly in the case of Air France, this can lead to a catastrophic chain of events.

I have the stall horn to alert me of getting to slow but I think I might have issues with being too fast.

I would opt for a straight in as I don't want to mess with base - final turns w/ no ASI.


Tomorrow is my BFR and just for grins after, I am going up w/ the CISP to do a bunch of slow flight, stalls at various attitudes and kind of play with that envelope a bit.

What do you do?
 
Pitch for airspeed, power for altitude.

Find the trim setting that gives you 80kts in your final landing configuration (before the ASI failure, obviously). In that condition, the airplane always seeks to find it. Remember that setting and don't touch it again. Fly the approach using power and let the airplane naturally oscillate - seeking the 80kts.

Round out and flare normally.
 
In a 172, 1900 RPM on downwind, descend at 1500 RPM, pitched for 500 FPM, readjusted with each notch of flaps.

Cruise is a nonissue.

Get an instructor and try this.

You also might try melting that bag off with pitot heat, if you still have a pitot tube.
 
Had that happen a few weeks ago. Not a bag but got a pitot full of fur at rotation speed taking off from the cabin site. Briefly thought i'd land on the long runway in town but by flying the aoa indicator as primary it made for an easy landing at the farm.
 
MAKG1 said:
In a 172, 1900 RPM on downwind, descend at 1500 RPM, pitched for 500 FPM, readjusted with each notch of flaps.

Cruise is a nonissue.

Get an instructor and try this.

You also might try melting that bag off with pitot heat, if you still have a pitot tube.
Click to expand...

I thought about the melting thing, but what if a piece then gets inside the pitot. Yuck. For me, it's MP and RPM and trim. At this point with the number of hours I have in my plane, I'm pretty comfy with what it should look like. Plus, if you've got AWOS on the field, you can always do a GS to airspeed calc if you've got a GPS.
 
JHW said:
Had that happen a few weeks ago. Not a bag but got a pitot full of fur at rotation speed taking off from the cabin site. Briefly thought i'd land on the long runway in town but by flying the aoa indicator as primary it made for an easy landing at the farm.
Click to expand...

I would probably aborted the landing after hitting the wallaby. :D
 
;) Fly the plane... I just had to say it.

One of the first things I did when I got my plane is learn the numbers. This was reinforced once again while working on my instrument ticket. Know YOUR numbers and settings, then fly the plane.

While a hand held or panel mount GPS will provide ground speed you will at least know the winds and have a good idea when on final what the airspeed should be.
 

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MAKG1 said:
In a 172, 1900 RPM on downwind, descend at 1500 RPM, pitched for 500 FPM, readjusted with each notch of flaps.
Click to expand...

Which model 172 and at what weight? I've mostly flown mid-seventies 172s with either 160 or 180 hp.

For me, normal settings in a 172 either solo or one other on board are about 1400 rpm and 400 fpm descent flying about a 1/2 to 3/4 mile pattern. I can see the higher rate of descent and higher power setting might work if you're heavy but it will be fast if you're light. When solo in a 180 hp, power would be a tad lower. The nice thing about those settings is once you're on speed with the first 10 degrees of laps, the airplane slows about 5 knots for each additional 10 degrees of flaps without re-trimming.

Anyway, for the OP, go do pattern work until the pitch and power settings are "burned in" then the airspeed indicator becomes something that is nice to have but not required. Remember to always keep the nose down on downwind-to-base and base-to-final.
 
You're talking a small GA plane, you should be able to feel the plane enough to get where you need to go without the ASI. I've had pre solo guys do a few laps in the pattern without allowing them to see their panel, if they can do it I'd think you should be able to as well.
 
MODS, this thread is offensive, please ban the OP.


(sorry, just wanted to try it. actually that was kinda fun!)
 
James331 said:
You're talking a small GA plane, you should be able to feel the plane enough to get where you need to go without the ASI. I've had pre solo guys do a few laps in the pattern without allowing them to see their panel, if they can do it I'd think you should be able to as well.
Click to expand...

I think I could do it in a 172.
As I sit here now, I know in the Cirrus I would end up coming in probably way faster than I should.
 
You should be able to land your plane with a towel covering the entire pattern. I had an instructor who used to do this.

There are plenty of warning prior to stall (and even prior to the stall horn) in a 172. We had a pitot tube block right after takeoff and it was no big thing to get to an airport and land (though we did choose one with a longer runway just in case).
 
James331 said:
You're talking a small GA plane, you should be able to feel the plane enough to get where you need to go without the ASI. I've had pre solo guys do a few laps in the pattern without allowing them to see their panel, if they can do it I'd think you should be able to as well.
Click to expand...


I had all kinds of instrument failures before solo, including a handful of trips around without any instruments.

Thanks to the IR, I now know specific RPM and pitch settings for various flight regimes, but pre-solo the goal was "keep the speed up". If you don't have an ASI and you're going to miss the ideal approach speed, a little fast seems like a better idea than too slow.
 
Like Gary said, learn your numbers, what power settings produce what speeds. In my Bo, I am 17" 2400 rpm in the pattern, just fly to the runway and maintain power like you usually do. The airframe don't care...
 
The other option is to try a spin with the pitot tube on the inside of the spin, or go vertical and back slide the plane, and that might created enough air disruption to remove the bag.
 
SixPapaCharlie said:
but it is not something that is specifically taught.
Click to expand...

What? You paid too much for that specific lesson.

I can still hear my primary CFI intoning the mantra: Pitch Plus Power equals Performance. And we flew it, too. Maybe a half dozen landings with the ASI covered.

It is a non-issue. -Skip
 
flyingron said:
You should be able to land your plane with a towel covering the entire pattern. I had an instructor who used to do this.

There are plenty of warning prior to stall (and even prior to the stall horn) in a 172. We had a pitot tube block right after takeoff and it was no big thing to get to an airport and land (though we did choose one with a longer runway just in case).
Click to expand...

:yes:

Ron,

This brought back some good memories and a laugh.

My instructor used to ride my ass about eyes in checking numbers...he took his coat off one day and the only thing I could see was the yoke. He said take us off, fly the pattern and land it. :yikes: If you don't know what pattern altitude looks like and can't judge your airspeed you're a long way from being a pilot. Of course he asked what my guesstimated airspeed was and altitude and HE confirmed. It taught me to learn my plane and the sight picture.
 
flyingron said:
You should be able to land your plane with a towel covering the entire pattern. I had an instructor who used to do this.

There are plenty of warning prior to stall (and even prior to the stall horn) in a 172. We had a pitot tube block right after takeoff and it was no big thing to get to an airport and land (though we did choose one with a longer runway just in case).
Click to expand...

It happened to me twice both in my cessna 140 and my Stearman. Not a big deal if your familiar with the plane your flying. In both cases I landed back at home base, a 2200 foot runway.( I was trained in the same way as above. )
 
If you've got a GPS use the ground speed for reference if approaching an airport near sea level and there's a ten knot headwind and your ground speed reads 60 you would know that your roughly at 70 knots airspeed. It's a great reference so long as you take into account your airports elevation and the wind speed
 
I've always wondered about the obsession with specific speeds at specific points in the pattern anyway. As the coat-over-the-panel exercises demonstrate, speeds obviously aren't critical. Repeatability?

I can see wanting to climb out at, say, Vy. And you probably don't want to stall before you're ready, and for some airplanes coming in too fast means a looooong float. But other than that, what's it matter?

Let's say you're flying a plane you're NOT familiar with (bringing it home for a friend or something). Seems like if you lost your ASI, you could do some slow flight on the way home, figure out what the RPM/MP settings and attitudes were, and then just do that on final and land. Should be relatively easy to figure out, even if you don't already know what the numbers are.
 
For a Cirrus driver....don't they train to pull the chute for every emergency? :D

Pull the chute is my vote....definitely. :yes:
 
Pick up my trusty iPad with Stratus and fore flight and turn on my trusty backup ahrs screen with synthetic vision? And wait till it blows off at 200 mph or so?
 
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I have experienced an inop airspeed indicator in a high performance aircraft due to one of these gizmos closing right after take-off:

e6c059ecd0321b4441d5ac78fa4f5d6b.jpg


As others mentioned, you need to know your numbers. It is a fairly benign event if you know the power settings that will give you the desired airspeed. But I will admit that the smell of raw adrenaline permeates the cockpit when it first happens...




Sent from my iPad using Tapatalk
 
SixPapaCharlie said:
You are at altitude 20 min from your destination (uncontrolled 4k ft runway) and it is Texas so one of those rogue plastic grocery bags has caught some lift and managed to get snagged on your pitot tube.

Curious about the different answers.
I know there are pilots that can feel their way to the ground but it is not something that is specifically taught.

Clearly in the case of Air France, this can lead to a catastrophic chain of events.

I have the stall horn to alert me of getting to slow but I think I might have issues with being too fast.

I would opt for a straight in as I don't want to mess with base - final turns w/ no ASI.


Tomorrow is my BFR and just for grins after, I am going up w/ the CISP to do a bunch of slow flight, stalls at various attitudes and kind of play with that envelope a bit.

What do you do?
Click to expand...

All of my pre-solo students had to do at least one pattern with the airspeed covered. Power + attitude = performance. The Wright brothers did just fine without an airspeed indicator. If you cannot land without one you are not ready for prime time.

Bob Gardner
 
I've flown a plane with a blocked static system a few times. One was the Navion and yes since the gear speed was 87 knots I had some fun trying to figure out how to tell when I was below that but I just used the AWOS and my GPS groundspeed to make that determination.

And yes, I meant put a towel over the PANEL not pattern.
 
I got my tailwheel endorsement in a twitchy little C-150 tail dragged with a broken airspeed indicator. It was great training. Feel the airplane, fly the airplane. Pretty simple.
 
EdFred said:
The other option is to try a spin with the pitot tube on the inside of the spin, or go vertical and back slide the plane, and that might created enough air disruption to remove the bag.
Click to expand...

The inside wing is more stalled than the outside wing but it' still moving forward. Tailsides are known to ram control surfaces hard against the stops and bend or break stuff. Dangerous for the guy with no training in such maneuvers.

Much better to use the usual power settings and watch the altimeter and VSI for excessive sink, which indicates low airspeed.

When I learned, and later taught, we sometimes covered various instruments including the ASI. When I had only about 70 hours I had a dead airspeed in a 150, and it was no big deal.

VFR should be fine. In IMC it's much more difficult.
 
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I had the pilot side pitot tube heat fail one time on a C-425. It finally froze over and the A/S indicator started acting like an altimeter.

I just used the co-pilot A/S for landing.
 
Use my backup panel on either my 496 or foreflight with the stratus.
 
Slow down until you get a stall chirp then lower the nose a little and maintain that configuration.

I have an angle of attack meter so it's academic. ASI is useless on very slow STOL approaches anyway ....
 
Give the controls to your copilot with an operational ASI. Done it before myself with a pitot cover left on. :wink2:

Personal aircraft? Worst case with no GPS one should know approx speeds with power.
 
Approach the airport normally, slow down so the wind in the wires is the usual pitch. Simple, really...

Ron Wanttaja
 
SixPapaCharlie said:
That would be a HUGE towel.
I Think you may be lying about this.
Click to expand...

My instructor did the same thing. Bought a big black bath towel and draped it over the glare shield so that it touched the rod the yoke is attached to (what do you call that?). We flew the pattern that way for the entire lesson.
 
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