poadeleted20
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...about embarassing foul-ups.
New PTS standards, in effect 6/2012
- Thread starter Tracey
- Start date
Alexb2000
En-Route
If the stall is fully developed, you're going to lose at least a little altitude, right?
denverpilot
Tied Down
Got a hard citation for that first claim? I've never seen anything in the accident record other than "failed to maintain airspeed / departure stall". There aren't categories for "departure stall where engine was definitely producing full power" and "departure stall where engine was producing 65%".
There's usually a "engine was producing power determined by metallurgy" and maybe if it survived "throttle was found in wide open position"... sometimes.
But I think you'll be hard-pressed to prove that the accident record shows a hard difference between known power outputs.
I'm the one who brought up the point about creeping throttles, and more to the point, lower than normal power being produced.
The PTS is teaching you to recognize and pitch, but a good instructor will also teach that the throttle hand goes forward simultaneously to make sure that thing up front is firewalled
(we'll leave engines with throttle handles that can put them above safe operating limits out if this for a minute, but there's an Air Florida crew dead from frozen instrumentation who'd be alive today if they shoved theirs up).
You keep saying it's an exercise to teach about recognizing a stall when no more power is available. If that's the case, I say that particular change to the PTS should include wording to the effect that the student needs to confirm that they really are.
Recognizing is but one step. Pitch is the next. Third is "why?".
How many people know roughly how many inches of MP their engine will put out up here at my home base before they start that takeoff roll, for example? How would that person know if they werent producing full power? How would they know to abort before lifting off on a hot day?
(There's multiple ways to tell, not just MP. My point here is the change to saying "full stall" is fine by me, but we've all seen folks who thought they were producing full power on a high DA takeoff who left the mixture full rich. The few who get it together and figure it out while in the middle of "recognizing" that they're on the edge of a stall after liftoff when they can't get out of ground-effect, survive.
The rest go into the record as a "departure stall" accident because they're not trained in that third step... figure out why it doesn't have enough power. The PTS doesn't require it. And it does get very little attention at lower altitude airports.
jesse
Touchdown! Greaser!
Without the time to look, I think that you'll find a large chunk of such incidents happen at high density altitudes, which means partial power, and can be verified by reading the NTSB reports.
Depends on your trajectory.
denverpilot
Tied Down
poadeleted20
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Already went through a bunch, and did not find a single one where a throttle slippage was involved.
denverpilot
Tied Down
Not being a pain, but do they specifically say when it wasn't a factor?
I still contend they're wont be reports of it because it's rarely possible to know for sure -- unless there's a specific notation that the position of the control was checked.
I rarely see that check documented in non-commercial GA accident reports.
I don't know many pilots who haven't had at least a partial power "loss" from a mis-set lever at least once, though.
Unless someone knows with certainty that it's a requirement of all NTSB teams to document the handle positions if the panel is intact (admittedly likely), and they're allowed to leave it out of the final reports (unlikely, but don't know).
It's not as important as recognizing and pitching to break the stall, understandably. There's just another step involved after that if you're going to train like you fight...
poadeleted20
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That makes it speculation on your part, and nothing more. I'll stick with actual recorded data.
denverpilot
Tied Down
Which is inconclusive about the topic. The data shows stalls. It doesn't show the reason why.
If you're not teaching students to look for the reason why they're stalling in a configuration they think is normal, but isn't... the recorded data will continue to show little change in the number of accidents, right? The definition of insanity is doing the same thing over and over and expecting a different outcome?
I can "recognize" the stall and even pitch to avoid it, all the way to the ground. I'd prefer to add looking at the MP gauge to see why it's happening and start troubleshooting the problem as soon as possible.
There's no added risk in asking students to verbalize "power full, and confirmed" at each power-on stall event. If teaching that procedure at high altitude there's no reason in the world to leave out the troubleshooting step. Omitting it will likely end up with a pilot who'll have about a 50/50 chance of brain-lock when it eventually happens to them.
Blind adherence to exactly the letter of the PTS can lead to holes in knowledge and procedures. "Everyone knows" you should check the power if you're slow and sinking and don't expect to be, doesn't cut it for every pilot. Some need to be shown that the pitch stall recovery is just the first step in saving their own butt. Further actions are required after the pitch to ensure survival in some cases.
Why not teach them?
gismo
Touchdown! Greaser!
I can list the likely most common causes for stalls in VMC (or IMC with a rated, current pilot) without referring to any statistical
data.
1) Desire/need for more lift, typically in a turn while close to the ground. This includes the classic base to final stall, the "impossible" turn, high DA departures, and buzzing. IMO the combination of unusual circumstances (i.e. a scenario rarely experienced) and proximity to the ground causes pilots to revert to a "primal" reaction rather than a rational response.
2) Distraction. Something has gotten hold of the pilots full attention and they instinctively add some back pressure and/or fail to notice that the power is not sufficient for the flight path they're on. This would include stalling on short final (flaring too early/high), falling out of a straight pattern segment, and a few similar situations where there's no direct intent to "pull up" to avoid contact with the ground.
The reduced power departure stall is intended to address one of the scenarios in group 1, most of the rest are taught from an avoidance (don't do this) perspective only IME (e.g. "Don't buzz", "don't overbank when turning final", "don't attempt to return to the runway if the engine quits" etc).
As near as I can tell, the primary approach to group 2 is pronouncements like "fly the airplane" and "aviate, navigate, communicate", none of which are likely to significantly affect behavior in the presence of a major distraction IMO. I suspect that the most effective remedy for those situations would be an AoA sensor tied to a throttled back TASER like device in the pilot seat.
Perhaps if the CFI were able to limit the application of throttle (e.g. by blocking further advance with a hand) opening the throttle would be a good addition to the standard departure stall technique. The problem I see with just letting the trainee go to full power during the recovery of a departure stall is that the resulting surge of thrust isn't likely to be there when the real event occurs at high DA and or when faced with rapidly approaching trees off the end of the runway. It's pretty clear to me that the PTS defined departure stall recovery is intended to ram home the facts that power is not required to break a stall and that additional power is likely to be unavailable at that time. And since the approach stall recovery does include going to WOT I suspect that most pilots are going to react to any stall with throttle as well as elevator. It's not like they're going to analyze the situation to determine if it more closely matches the departure or approach scenario and react differently.
Jaybird180
Final Approach
I had an impending stall once on departure. Hot, humid day. Airplane didn't want to climb (didn't know the engine was a dog) was at full gross. Short field technique (Vx to Vy my a$$). It was only training that caused me to NOT pull as the trees barely passed beneath the landing gear. Then after I’d pulled the flaps and the airplane began sinking with the stall warning going off, I instinctively PUSHED to unload (was at about 150’ AGL), rolled into a right turn and noticed the power lines at 9 O’Clock high.
I’m in the group that doesn’t know (see above).
Jaybird180
Final Approach
Because that instinct will be ingrained from power-off stall recovery training.
I hold no such suspicions after AF447 or Colgan, at this point I don't trust the ability for pilots to be screened for ability to react.
+1...
That is why I prefer to be the one in the left seat flying any plane... I don't want to be taken out by some idiot who gets past the carrier sim flightcheck out only to find out they cannot recognize an stall..... If I am going out, it is because of my stupidy.....
Well, you did say "way" after rotation speed. You want a smooth ride for the passengers...raise the nose wheel early and smooth, hold the attitude and let it fly off. No reason to even look at the ASI. No reason to stay on the ground longer than necessary. Jesse was coming from the standpoint of good and artful flying technique.
jpower
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Do you mean the changes between the last one and this one? If so, that will take much less than a page. Off the top of my head:
- Emergency descent added
- Added demonstration of a fully developed stall
- Emphasis on cockpit resource management
bflynn
Touchdown! Greaser!
Didn't they also add an emergency descent as one of the optionally requested flight manuevers? I remember when I read this when it first came out, that was the big change I saw. The rest of it was mostly just beefing up what was already there.
ainokea
Pre-takeoff checklist
Read this version of the latest PTS. It easily shows the changes.
http://www.2012pts.com/2012PTS.pdf
http://www.2012pts.com/2012PTS.pdf
ebetancourt
Line Up and Wait
Depends on the wing. Some airplanes will not respond well to this technique. Mooney and most jets come to mind. All this will do is lengthen the T/O roll.
Yeah I know 747s don't do that either. I think she's flying a Cessna. Works fine in those.
TMetzinger
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Each airplane is different - on some beat-up trainers the nosewheel will start shaking as the load on it is lifted. You may add a little back pressure to get the nosewheel off at that point but not rotate fully.
Assuming a smooth runway and an airplane in good shape, it's best to concentrate on maintaining the centerline, sneak a glance at the ASI now and again, and when you've reached the rotation speed and the airplane feels ready to fly (and with practice you'll know what it feels like), gently raise the nose to the takeoff attitude and fly away.
As others have noted - raising it too early increases the takeoff roll length, even in Cessnas, though it's not as dramatic an increase as it can be in something like a Mooney.
Assuming a smooth runway and an airplane in good shape, it's best to concentrate on maintaining the centerline, sneak a glance at the ASI now and again, and when you've reached the rotation speed and the airplane feels ready to fly (and with practice you'll know what it feels like), gently raise the nose to the takeoff attitude and fly away.
As others have noted - raising it too early increases the takeoff roll length, even in Cessnas, though it's not as dramatic an increase as it can be in something like a Mooney.