Airspeed is... WTF... alive?

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Phillip

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Phillip
Youtube cannot lie, so the question: why anyone care for the airspeed to be undead at takeoff?

In thousands of youtube videos of various takeoffs the incantation of the airspeed verility from the PIC comes at the critical time between forward throttle and liftoff. Thinking rationally about this, among the several performance indicators that are truly important at takeoff (RPM, Fuel Pressure) and general desirability of keeping eyes outside why would anyone care about validating the pitot static system then and there. It is not critical for the flight at that point, so why even bother?

I was taught to keep my eyes outside the cockpit at all time during takeoff. I am somewhat lax at that since majority of my flights originate and terminate at class Charlie airport where there are others tasked with assuring the separation. So I do briefly check the RPM and Fuel Pressure during acceleration, simply because the loss of those would leave me next no time to react. But the thousands of takeoffs on youtube, which cannot lie, make no references to RPM or FP, and the incessant parroting of "Airspeed is alive" makes me suspect there is a secret society of pitot static observers I was not somehow invited to join.

Anyways, whats with the "Airspeed is alive" magic spell?
 
It's a common call out,when flying bigger aircraft.
 
Many airspeed indicators in aircraft do not show airspeeds below a certain point, such as 40 or 50 knots. "Airspeed alive" means that the aircraft has passed this speed and the airspeed indicator has started to move above the minimum speed that it can display.

Also it helps to validate that both the indicator is working and that you are making speed at the expected rate. If the indicator is neither "alive" nor making the speed you expect by the point you expect, it's a good idea to reconsider takeoff and abort.

You could have a bogus RPM reading due to a failed gauge, fuel flow is least important to me.
 
I did my IR through the Air Force base aero club and they required the call out. The reasoning was that a verbal call out plus visual check makes sure you are checking gauges and that the plane is performing the expected way or you will know and abort.
 
Caramon13 said:
You could have a bogus RPM reading due to a failed gauge, fuel flow is least important to me.
Click to expand...

Good points about bigger craft. The Cherokees and the Cessna I fly though can takeoff at 40-50.

Bogus RPM is less likely that bogus Airspeed. There is runup that can, more or less, validate the RPM gauge functioning. There is no such runup check of the pitot static system.... By that rationale RPM reading is more trustworthy than the Airspeed.
The loss of FP can mean dead engine right then and there, which (to me at least) is way more important than oil pressure. The engine will run without oil, it won't without fuel.
 
Phillip said:
Youtube cannot lie, so the question: why anyone care for the airspeed to be undead at takeoff?

In thousands of youtube videos of various takeoffs the incantation of the airspeed verility from the PIC comes at the critical time between forward throttle and liftoff. Thinking rationally about this, among the several performance indicators that are truly important at takeoff (RPM, Fuel Pressure) and general desirability of keeping eyes outside why would anyone care about validating the pitot static system then and there. It is not critical for the flight at that point, so why even bother?

I was taught to keep my eyes outside the cockpit at all time during takeoff. I am somewhat lax at that since majority of my flights originate and terminate at class Charlie airport where there are others tasked with assuring the separation. So I do briefly check the RPM and Fuel Pressure during acceleration, simply because the loss of those would leave me next no time to react. But the thousands of takeoffs on youtube, which cannot lie, make no references to RPM or FP, and the incessant parroting of "Airspeed is alive" makes me suspect there is a secret society of pitot static observers I was not somehow invited to join.

Anyways, whats with the "Airspeed is alive" magic spell?
Click to expand...
You can blame your original CFI for not 'inviting' you into the club.

A good pilot checks both engine instruments and airspeed during the takeoff roll.

Since you are already in the habit of looking at looking at RPM and FP (I personally would be more concerned with Oil Pressure than Fuel Pressure though) it should not be any more challenging to validate that the ASI is working as well.

Can you safely takeoff and land a small GA airplane without a working ASI: yes, but unless you practice that frequently, why force yourself into an abnormal operation when you can simply and quite safely abort the takeoff and get it fixed???
 
I think it's kinda important that the airspeed indicator is working for most flights and is kinda real important right during lift off for a lot of flights.
 
I do it, and it is a reminder to me to do an overall check of my performance instruments before I rotate. Plus a functioning ASI is required equipment as per 91.205:

A – airspeed indicator
T – tachometer (for each engine)
O – oil pressure gauge (for each engine using a pressure system)
M – manifold pressure gauge (for each altitude engine)
A – altimeter
T – temperature gauge (for each liquid cooled engine)
O – oil temperature gauge (for each air cooled engine)
F – fuel gauge
L – landing gear position indicator
A – anti collision lights (for aircraft certified after March 11th 1996)
M – magnetic compass
E – ELT
S – safety belts

Everything else can be checked on the ground during taxi and run-up. The ASI not so much, so you have to check it on your take-off roll.
 
Phillip said:
The loss of FP can mean dead engine right then and there, which (to me at least) is way more important than oil pressure. The engine will run without oil, it won't without fuel.
Click to expand...
If this question is serious and not trolling....please think about this: If you have a fuel pressure problem (fuel pump not working properly) it is going to be far more apparent from other indications - not making full RPM, takeoff roll sluggish, engine doesn't sound right...etc.

If you don't have proper oil pressure because of a pump failure or blockage - you are right, it is not going to be immediately apparent. The airplane will take off and the engine will keep running at full takeoff power.....until it doesn't which could very well be at 3-400' AGL. If you are going to check any gauge on the takeoff roll, I would argue that OP is the most important.
 
Phillip said:
Good points about bigger craft. The Cherokees and the Cessna I fly though can takeoff at 40-50.

Bogus RPM is less likely that bogus Airspeed. There is runup that can, more or less, validate the RPM gauge functioning. There is no such runup check of the pitot static system.... By that rationale RPM reading is more trustworthy than the Airspeed.
The loss of FP can mean dead engine right then and there, which (to me at least) is way more important than oil pressure. The engine will run without oil, it won't without fuel.
Click to expand...

There is no benefit that I can discern that comes from not using ALL the available information. You can argue that one indicator is more important than another if you wish, but your scan shouldn't be excluding any of them. On every take-off I audibly call out the IAS at each 10 knot interval to my pre-planned rotation speed as a check against time since opening the throttles. There's a certain cadence from doing it over and over and if it isn't on that cadence its one more way I know something isn't quite right before I leave the ground.
 
Fearless Tower said:
A good pilot checks both engine instruments and airspeed during the takeoff roll.
Click to expand...

I was taught three callouts on the takeoff roll:


  1. After fully advancing the throttle, check MP and RPM, and if good, call "engine power good", if not, abort.
  2. Check all the other engine gauges and vacuum, if good, call "gauges in the green", if not, abort.
  3. By then airspeed should be off the peg, if so, call "airspeed alive", if not, abort.
 
There's not much difference between Airspeed alive and Vr in my plane. It becomes pretty apparent that the airspeed isn't working if I'm not heading towards Vr shortly after the takeoff roll commences.

There's not much point in "calling" airspeeds in a single pilot operation anyhow. You just act on whatever the speed means (V1, Vr, whatever...).
 
While checking the ASI on the takeoff roll, I observed it suddenly drop to about zero.

Long enough runway to easily abort. Went back to the FBO and the mech fished a dead bug out of the pitot. How is that for a lucky shot?

-Skip
 
Yeah, in fact Oil Pressure is the first thing I check after engine start to make sure it's where it needs to be, if it's not where it needs to be within a few seconds, shut the engine down. You should be doing it again at run-up (or should be, if you aren't well shame on you).

The Cherokee I fly has an aux fuel pump on for critical phases of flight as well (I think a LOT of piston aircraft have this). I'll maybe glance at the fuel flow, but my eyes are glued to RPM and speed and listening for any engine issues.

I'll admit I don't probably pay as MUCH attention to the oil gauges during the roll since I just checked them at run-up, but on climbout you bet I am.
 
Fearless Tower said:
You can blame your original CFI for not 'inviting' you into the club.

A good pilot checks both engine instruments and airspeed during the takeoff roll.

Since you are already in the habit of looking at looking at RPM and FP (I personally would be more concerned with Oil Pressure than Fuel Pressure though) it should not be any more challenging to validate that the ASI is working as well.

Can you safely takeoff and land a small GA airplane without a working ASI: yes, but unless you practice that frequently, why force yourself into an abnormal operation when you can simply and quite safely abort the takeoff and get it fixed???
Click to expand...

I do check the ASI and the FP/RPM. The goals here are safety and the efficient use of my mental focus (limited resource). What I've observed is that I look at the panel way too much, cause that's how my mind is wired, I am an engineer by trade. Where I want to get to is eyes out all the time except the specific and limited cockpit tasks. Right now with the time I spend looking at the panel I am making myself less safe than I could be.

THe airspeed is alive callout reminds me of the "Stop, do not move" callout in armed self defense classes. Both seem perfunctory and somewhat disingenious to me. :)
 
Fearless Tower said:
A good pilot checks both engine instruments and airspeed during the takeoff roll.
Click to expand...

Yeah, I'm a bit lost on why someone would choose not to do this. My CFI always has me glance down to make sure everything is "in the green" during takeoff roll (especially oil temp & pressure). When I do that, I also quickly check my ASI and RPM. Figure it's best to abort a takeoff than deal with problems airborne...
 
If I'm departing IFR into a low ceiling, an immediate return and land in case the ASI is inop may not be safe. In that case I DEFINITELY want to be sure it's functioning properly before I'm wheels up.
 
Phillip said:
Youtube cannot lie, so the question: why anyone care for the airspeed to be undead at takeoff?

In thousands of youtube videos of various takeoffs the incantation of the airspeed verility from the PIC comes at the critical time between forward throttle and liftoff. Thinking rationally about this, among the several performance indicators that are truly important at takeoff (RPM, Fuel Pressure) and general desirability of keeping eyes outside why would anyone care about validating the pitot static system then and there. It is not critical for the flight at that point, so why even bother?

I was taught to keep my eyes outside the cockpit at all time during takeoff. I am somewhat lax at that since majority of my flights originate and terminate at class Charlie airport where there are others tasked with assuring the separation. So I do briefly check the RPM and Fuel Pressure during acceleration, simply because the loss of those would leave me next no time to react. But the thousands of takeoffs on youtube, which cannot lie, make no references to RPM or FP, and the incessant parroting of "Airspeed is alive" makes me suspect there is a secret society of pitot static observers I was not somehow invited to join.

Anyways, whats with the "Airspeed is alive" magic spell?
Click to expand...

If you are looking at videos of airline or crew operations, keep in mind that there are two people. The non-flying pilot is the one checking the instruments and doing the airspeed alive callout while flying pilot is looking outside.
 
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Phillip said:
Good points about bigger craft. The Cherokees and the Cessna I fly though can takeoff at 40-50.

Bogus RPM is less likely that bogus Airspeed. There is runup that can, more or less, validate the RPM gauge functioning. There is no such runup check of the pitot static system.... By that rationale RPM reading is more trustworthy than the Airspeed.
The loss of FP can mean dead engine right then and there, which (to me at least) is way more important than oil pressure. The engine will run without oil, it won't without fuel.
Click to expand...

In my mind the objective during the take off sequence is to detect any anomaly and act appropriately as early as possible, preferably before leaving the ground.

No argument that a total loss of FP means a dead engine rather quickly. A partial loss of FP will probably show up as a loss of engine RPM and reduced acceleration. Personally, ignoring the oil pressure might just get you killed one day.
 
flyingron said:
There's not much difference between Airspeed alive and Vr in my plane. It becomes pretty apparent that the airspeed isn't working if I'm not heading towards Vr shortly after the takeoff roll commences.

There's not much point in "calling" airspeeds in a single pilot operation anyhow. You just act on whatever the speed means (V1, Vr, whatever...).
Click to expand...

:yes:

I push to takeoff power, check that I'm getting it and that all the instruments are in the green, then start monitoring the airspeed to know when to rotate. I don't feel the need to say "airspeed is alive", I'm watching it anyway. If it stays at zero or doesn't get to Vr before my abort point then I will abort.
 
Cajun_Flyer said:
Yeah, I'm a bit lost on why someone would choose not to do this. My CFI always has me glance down to make sure everything is "in the green" during takeoff roll (especially oil temp & pressure). When I do that, I also quickly check my ASI and RPM. Figure it's best to abort a takeoff than deal with problems airborne...
Click to expand...

Because you don't need it for a safe VFR flight. I was taught to fly via external references (ground/sky in the windshield, for ex), rather than by the instruments.
At takeoff various crucial things can happen. You can have a runway excursion(incursion?), you can have wildlife on the runway, wind gusts, birds.. I'd rather not be caught looking inside.
 
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Phillip said:
I do check the ASI and the FP/RPM. The goals here are safety and the efficient use of my mental focus (limited resource). What I've observed is that I look at the panel way too much, cause that's how my mind is wired, I am an engineer by trade. Where I want to get to is eyes out all the time except the specific and limited cockpit tasks. Right now with the time I spend looking at the panel I am making myself less safe than I could be.

THe airspeed is alive callout reminds me of the "Stop, do not move" callout in armed self defense classes. Both seem perfunctory and somewhat disingenious to me. :)
Click to expand...


Sounds like you are allowing yourself to get fixated on the panel. You want to be looking for "differences from normal" without staring at any one indicator excessively.
 
Phillip said:
At takeoff various crucial things can happen. You can have a runway excursion, you can have wildlife on the runway, wind gusts, birds.. I'd rather not be caught looking inside.
Click to expand...
If you have a loss of control or runway excursion due to glancing down to confirm ASI is working, you are doing it wrong.

youre_doing_it_wrong.jpg
 
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GRG55 said:
You want to be looking for "differences from normal" without staring at any one indicator excessively.
Click to expand...

Again this is focus management problem. "different from normal" is somewhat non-specific and open ended. I want to pair it down to what's absolutely necessary. Cause I'll have plenty of time to reflect on "different from normal" after I've got handed off to approach and given the initial heading. At that point I am still within circle back distance from the field...
 
Phillip said:
Again this is focus management problem. "different from normal" is somewhat non-specific and open ended. I want to pair it down to what's absolutely necessary. Cause I'll have plenty of time to reflect on "different from normal" after I've got handed off to approach and given the initial heading. At that point I am still within circle back distance from the field...
Click to expand...
If you want to be obstinate about it, I guess it depends on where you want to go with this aviation thing: If you know for a fact that all you ever are going to do with aviation is fly a J-3 Cub around the pattern then fine- forget about the ASI.

But, if you ever think you might, just might venture into more advanced aircraft and things like instrument flying (like Azure mentioned), then you best get this into your routine. Develop the habit now or it will be a lot harder later.
 
you kind of answered the question yourself..........it's on youtube so it's gotta be correct.

but seriously, I can't imaging using "I need to focus my attention outside" as a reason not to take a nanosecond to check airspeed.

maybe I missed it or should know, but are you still training or PPL'd? just curious.
 
Cajun_Flyer said:
Yeah, I'm a bit lost on why someone would choose not to do this.
Click to expand...

Every airplane and situation is different. When your high-powered, highly sensitive, blind as a bat tailwheel airplane is based on a very narrow runway, and breaks ground about 5 seconds after pushing the throttle in, your eyeballs are outside the airplane until it's in the air. It would be pointless and foolish to attempt to scan multiple instruments during those few seconds. If you fly a tricycle airplane that allows you to trim your toenails during the takeoff roll, scan to your heart's content.
 
Phillip said:
Good points about bigger craft. The Cherokees and the Cessna I fly though can takeoff at 40-50...
Click to expand...


According to the POH, the ones I fly take off at 65 and 55 respectively.


If you read the "dumb things I've done" threads on various flying forums, there are many accounts of people who forgot to take off the pitot tube cover before take-off. Its just a check and it never hurts to verbalize your checks.
 
RoscoeT said:
Every airplane and situation is different. When your high-powered, highly sensitive, blind as a bat tailwheel airplane is based on a very narrow runway, and breaks ground about 5 seconds after pushing the throttle in, your eyeballs are outside the airplane until it's in the air. It would be pointless and foolish to attempt to scan multiple instruments during those few seconds. If you fly a tricycle airplane that allows you to trim your toenails during the takeoff roll, scan to your heart's content.
Click to expand...
A bit of an exaggeration. I fly a lot of different Tailwheels (including a radial engine biplane) and I still find the time to check the ASI. Just not that hard.
 
Skip Miller said:
While checking the ASI on the takeoff roll, I observed it suddenly drop to about zero.

Long enough runway to easily abort. Went back to the FBO and the mech fished a dead bug out of the pitot. How is that for a lucky shot?

-Skip
Click to expand...

Good example. Most of the time I take off from a 9000 runway at sea level. Plenty of room to abort. But then there can be those (short field) situations where aborting is of greater risk than continuing takeoff and circling back for landing. ASI is not really necessary for a safe VFR flight. Especially nowadays with secondary airspeed indicators (ex GPS).
 
Phillip said:
Because you don't need it for a safe VFR flight. I was taught to fly via external references (ground/sky in the windshield, for ex), rather than by the instruments.
Click to expand...

One of the questions on the written is about always prioritizing and trusting the instruments over your senses, especially during emergency situations. I get what you are saying and I do that too (using external references to feel out angles, speeds and distances), but, at the end of the day, human error is notorious and the FAA apparently prefers we not rely on those things.


Phillip said:
At takeoff various crucial things can happen. You can have a runway excursion(incursion?), you can have wildlife on the runway, wind gusts, birds.. I'd rather not be caught looking inside.
Click to expand...

In my short time as a pilot, I've found being safe is all about being a precise, effective multi-tasker. I'm not talking about fumbling around with stuff in the cockpit during takeoff roll, or staring for a long time at all your instruments without keeping your peripheral vision sharp and glancing back up frequently. I'm talking about quickly making sure everything is in the green and the ASI and RPM gauges are doing what they should be. Again, rather know these things before I lift off the ground.
 
eman1200 said:
you kind of answered the question yourself..........it's on youtube so it's gotta be correct.

but seriously, I can't imaging using "I need to focus my attention outside" as a reason not to take a nanosecond to check airspeed.

maybe I missed it or should know, but are you still training or PPL'd? just curious.
Click to expand...

I do (check the ASI). I am PPLd with fairly short hours (about 200TT). I am at the point where the routine aviating tasks are more or less habitual and I can pay some attention to analysing/questioning my cockpit "habits".
 
RoscoeT said:
Every airplane and situation is different. When your high-powered, highly sensitive, blind as a bat tailwheel airplane is based on a very narrow runway, and breaks ground about 5 seconds after pushing the throttle in, your eyeballs are outside the airplane until it's in the air. It would be pointless and foolish to attempt to scan multiple instruments during those few seconds. If you fly a tricycle airplane that allows you to trim your toenails during the takeoff roll, scan to your heart's content.
Click to expand...


Well, obviously there are always exceptions. But the OP is talking about what typical pilots in typical situations are out there doing.
 
Cajun_Flyer said:
Well, obviously there are always exceptions. But the OP is talking about what typical pilots in typical situations are out there doing.
Click to expand...

Well, pilots are like doctors, in that they do things the same exact way every time. Cause the safety is in following the protocol in either ultra conservative endeavor. Hence the quest for a perfect protocol...
 
RoscoeT said:
Nope. Ever had a 540-powered Pitts based on a 30' wide runway?
Click to expand...

Of course not. And just how many people DO just that?

That is just my point: for the vast majority of operations nose or taildragger, it is just not that hard to glance at the ASI during the initial takeoff roll. Stop trying to make it some boogeyman that causes airplanes to careen off the runway if people look down at their instruments.
 
Phillip said:
Well, pilots are like doctors, in that they do things the same exact way every time. Cause the safety is in following the protocol in either ultra conservative endeavor. Hence the quest for a perfect protocol...
Click to expand...
So again, get in the habit now or limit your flying.
 
Bill Jennings said:
I was taught three callouts on the takeoff roll:


  1. After fully advancing the throttle, check MP and RPM, and if good, call "engine power good", if not, abort.
  2. Check all the other engine gauges and vacuum, if good, call "gauges in the green", if not, abort.
  3. By then airspeed should be off the peg, if so, call "airspeed alive", if not, abort.
Click to expand...

This for technique ^

Also OP, I think it's important to note that when the people in the videos are saying "airspeed alive" first, then "instruments in the green" the issue I have is, are they focused on the ASI until it starts moving and THEN checking other data? If so, there is a serious disconnect in instrument scanning on power up roll. I know, because I had that horrible habit when I first started flight training.

For me personally, my technique at "throttle up" is the following:

Manifold Pressure
RPM
Look outside
Oil Pressure
Oil / CH temps
Suction
Look outside
Airspeed
Oil Pressure
Look outside
Fuel flow/level
Airspeed
Flaps
Trim
Look outside
Rotate
(note, I consider oil pressure and manifold pressure to be the canaries in the coal mine)
 
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