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ok I get departure stall. but why departure stall?


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After sleeping on it, you are correct and I need to reword what i said. When we pull power, the engine will respond just as you say, like a piston. I was confusing the total acceleration and stability of the plane and thrust. With the acceleration difference in the king air vs a small 2000lb max airplane I would still imagine pulling power would only work if the situation hadnt reached a critical point. 
 
In this incident, i believe he sits for a second, spooling the engine, and then goes to full power. He gets off the ground in a very short distance. As he gets to the point he notices there's a problem, and Im going to assume he does pulling power, as it looks as if the plane is developing into a spin. And a spin at 300ft isnt going to be a fun time, as shown in that video. I also do not see a clear deflection of controls as well. 
 
I think you're right on people not being wired to pull power in an emergency. We are taught early on that stall recovery is adding, if not full, power. Even if you can recover just by pushing the nose over, the basic instinct for most people always seems to be adding in power. 

I wondered about an over torque or runaway prop situation. Is it possible that he lost rudder authority and that allowed it to roll off to the P factor side?


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10 minutes ago, Marauder said:


I wondered about an over torque or runaway prop situation. Is it possible that he lost rudder authority and that allowed it to roll off to the P factor side?


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I dont think it would be either those issues. I still believe it was some sort of flight control issue. 

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22 minutes ago, Mooney Dog said:

I dont think it would be either those issues. I still believe it was some sort of flight control issue. 

My thoughts as well. Any TD pilot is stirring the stick during during taxi.  For take off, stick comes back (not too much or tail wheel can shimmy) until the tail is ready to fly, then stick comes forward enough to lift the tail. Depending on attitude the stick may come back at lift off speed to initiate lift off and climb. This is an odd one. One thing is certain, he did not have pitch control and perhaps no roll either.   Not much travel in the seats so it seems unlikely a seat letting go of the rails would cause this.  The seatbacks on the other hand do appear to be adjustable. If the seatback failed that could cause a host problems but that seems unlikely as well. 

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There's a pic online elsewhere of the rear seat stick installation, and shows that the hinge mechanisms are essentially exposed.   If there was something loose in the cockpit that got in there it could explain both elevator and aileron impediment.   This is the accident aircraft.

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2 hours ago, Nukemzzz said:

Is this a seat adjuster failure?  The seat slides back as you are holding the stick. If you hold on too long you are screwed. If you let it go you are screwed. 

Looks like this seat only slides a couple of inches, so little screwing is going on here. Just means that it was something else, cause Snort sure enough got screwes.

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On 8/9/2021 at 2:43 PM, Shadrach said:

My thoughts as well. Any TD pilot is stirring the stick during during taxi.  For take off, stick comes back (not too much or tail wheel can shimmy) until the tail is ready to fly, then stick comes forward enough to lift the tail. Depending on attitude the stick may come back at lift off speed to initiate lift off and climb. This is an odd one. One thing is certain, he did not have pitch control and perhaps no roll either.   Not much travel in the seats so it seems unlikely a seat letting go of the rails would cause this.  The seatbacks on the other hand do appear to be adjustable. If the seatback failed that could cause a host problems but that seems unlikely as well. 

Some aircraft, the T-6 Texan and the P-51 and all Thrush crop dusters have locking tail wheels, to unlock them the stick is released and allowed to fall full forward, so you taxi without touching the stick, then before takeoff you pull the stick back, this locks the tail wheel and you go. All of those aircraft were North American / Rockwell designs and an automatic locking tail wheel was considered desirable, other aircraft the tail wheel has to be locked prior to takeoff

On smaller and lighter tailwheel aircraft that have Mr Maule’s tailwheel design, (steerable tailwheel was a Maule  invention) it’s common to taxi with the stick aft to help prevent nose over and stick into the wind just like you do all small aircraft.

I can’t imagine why anyone would be moving the stick around during taxi?

But I concede your point that anyone should notice control locks engaged, but for some reason many haven’t.

‘I know nothing about this aircraft and have been wondering what turbine is only 400 HP? sort of small for most turbines. Even the -21 Bill Hatfield uses on his 206 conversions is 550 SHP, but you can derate anything.

Edited by A64Pilot
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13 hours ago, A64Pilot said:

Some aircraft, the T-6 Texan and the P-51 and all Thrush crop dusters have locking tail wheels, to unlock them the stick is released and allowed to fall full forward, so you taxi without touching the stick, then before takeoff you pull the stick back, this locks the tail wheel and you go. All of those aircraft were North American / Rockwell designs and an automatic locking tail wheel was considered desirable, other aircraft the tail wheel has to be locked prior to takeoff

On smaller and lighter tailwheel aircraft that have Mr Maule’s tailwheel design, (steerable tailwheel was a Maule  invention) it’s common to taxi with the stick aft to help prevent nose over and stick into the wind just like you do all small aircraft.

I can’t imagine why anyone would be moving the stick around during taxi?

But I concede your point that anyone should notice control locks engaged, but for some reason many haven’t.

‘I know nothing about this aircraft and have been wondering what turbine is only 400 HP? sort of small for most turbines. Even the -21 Bill Hatfield uses on his 206 conversions is 550 SHP, but you can derate anything.

Stiring the stick was my euphemism for verifying free and correct as well as orienting ailerons and elevator for wind conditions. At my airport going for my hanger to the runway means facing the airplane into at least three of the cardinal directions. There is NFW that I’m arriving at the hold short line without deflecting all of the flight controls several times. In the Mooney I push the yoke full forward whenever there’s a passenger entering the aircraft. During Taxi I watch the yoke to ensure it turns in the opposite direction of my ground turns (this verifies the operation of the wing leveler). My point was that in addition to “controls free and correct” there are a number of reasons to move the stick/yoke prior to takeoff.

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  • 10 months later...

The control lock allowed you to taxi the plane because it did not lock the rudder.   But did lock the control surfaces.   another pilot has taken off with the lock in place but was able to get it out in time.

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In light wind conditions you don’t need to use the stick to taxi, just your feet.

But I would think in any airplane with a stick that it being locked would be noticed as usually a stick falls full forward on its own at slow or no speed with the elevator being full down, so before takeoff you reach forward, grab it and pull it back to neutral position. If there is an aileron / rudder interconnect the stick moves left and right with rudder too, unless locked.

I’ve not seen an airplane with a stick that didn’t fall forward when released at taxi speeds, but assume some don’t.

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2 hours ago, EricJ said:

It seems particularly odd to not know the control lock was in place in a taildragger.

Yeah.  I cannot imagine. In a tail dragger with a stick, I’ve already verified stick movement before hitting the starter. Sometimes just getting in requires movement of the stick. Also, the PTT switch is usually on the stick. So hard to not notice it being locked.

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1 hour ago, Shadrach said:

Yeah.  I cannot imagine. In a tail dragger with a stick, I’ve already verified stick movement before hitting the starter. Sometimes just getting in requires movement of the stick. Also, the PTT switch is usually on the stick. So hard to not notice it being locked.

FAA years ago spent quite a lot of money to determine why people just out of the blue would do something foolish, like for instance the guy that drives the same way to work everyday, one day doesn’t stop at the stop sign that’s been there for years.

They offered grants to College’s to study it, poor sleep, fatigue, medication etc we’re all ruled out. Only conclusion was that rarely people will just do something or not do something that they always do, for no reason, only thing that came from the studies was an acronym, SLOJ, or sudden loss of judgement.

My belief is it’s often a sign of complacency, you just get real comfortable with something and forget to do something.

The most likely people to suffer from SLOJ are the high time experienced people.

Before I moved here there was a double fatality in my neighborhood, both were very experienced one with over 10,000 hours, ATP etc., took off leaned out, aircraft crashed soon after takeoff. 

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2 hours ago, A64Pilot said:

FAA years ago spent quite a lot of money to determine why people just out of the blue would do something foolish, like for instance the guy that drives the same way to work everyday, one day doesn’t stop at the stop sign that’s been there for years.

They offered grants to College’s to study it, poor sleep, fatigue, medication etc we’re all ruled out. Only conclusion was that rarely people will just do something or not do something that they always do, for no reason, only thing that came from the studies was an acronym, SLOJ, or sudden loss of judgement.

My belief is it’s often a sign of complacency, you just get real comfortable with something and forget to do something.

The most likely people to suffer from SLOJ are the high time experienced people.

Before I moved here there was a double fatality in my neighborhood, both were very experienced one with over 10,000 hours, ATP etc., took off leaned out, aircraft crashed soon after takeoff. 

So the SM.1019 definitely incorporates a number of controls into the stick. The report says that the trim was full nose down perhaps indicating an attempt to recover. In an aircraft with tab controlled elevator trim that would have done nothing to help and perhaps exacerbated the nose up pitch condition.  I keep coming back to the fact that For this accident to have occurred as the NTSB suggests, he likely hast to set trim and communicate with tower using PTT without noticing the stick locked in place. Furthermore, it seems unlikely that an experienced Tailwheel pilot would start his takeoff roll without the stick aft.

Color me skeptical of the NTSB’s analysis.

 

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6 minutes ago, Shadrach said:

Furthermore, it seems unlikely that an experienced Tailwheel pilot would start his roll without the stick aft.

I'd think it'd be highly unusual to not do *something* with the elevator at the beginning of the takeoff roll, like push it forward to help raise the tail, or just make adjustments keep the tail where you want it, with enough time margin to pull the throttle back off before lift off if it was stuck.    I suppose it is possible that that particular airplane could be flown off the runway with little to no stick input, and maybe it was tempting to do that because it was kinda fun or something, but def not a great idea.   

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On 7/8/2022 at 6:34 PM, EricJ said:

I'd think it'd be highly unusual to not do *something* with the elevator at the beginning of the takeoff roll, like push it forward to help raise the tail, or just make adjustments keep the tail where you want it, with enough time margin to pull the throttle back off before lift off if it was stuck.    I suppose it is possible that that particular airplane could be flown off the runway with little to no stick input, and maybe it was tempting to do that because it was kinda fun or something, but def not a great idea.   

Perhaps there are different techniques that I’ve not been exposed to, but I was always taught to start my take off roll in a taildragger with thr stick near full aft, then decreasing back pressure transitioning to forward pressure as speed builds to lift the tail.  I’ve never taken off the tail dragger with the stick in it”s neutral position. It’s always an exercise in maximizing Tailwheel control until transitioning control to the tail control surfaces.

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Most tailwheel drivers push forward on the stick at the beginning of the takeoff roll to lift the tail, that way you can see over the nose better and it seems the rudder has more authority with it up, I’m not sure why you were taught to hold the tail down

Many are convinced with the fuselage level that the airplane accelerates faster, you will see in STOL competitions the tail come up for a few feet then usually slam the ground as they try to takeoff early, Pro’s will takeoff with the tail wheel just about to touch. 

My testing showed that at least for a heavily loaded Ag plane that it made no measurable difference.

But I concede what I assume your point is, that’s it’s unusual for some control movement to not be made in the takeoff roll. Maybe he normally set trim where he knew she would fly and just let herself fly off?

However I stand by my assertion that every once in a while even a very experienced, professional pilot can make a foolish error, one that just doesn’t make sense given their experience and past record.

But his accident video sure looks like frozen controls to me.

 

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1 hour ago, A64Pilot said:

Most tailwheel drivers push forward on the stick at the beginning of the takeoff roll to lift the tail, that way you can see over the nose better and it seems the rudder has more authority with it up, I’m not sure why you were taught to hold the tail down

Many are convinced with the fuselage level that the airplane accelerates faster, you will see in STOL competitions the tail come up for a few feet then usually slam the ground as they try to takeoff early, Pro’s will takeoff with the tail wheel just about to touch. 

My testing showed that at least for a heavily loaded Ag plane that it made no measurable difference.

But I concede what I assume your point is, that’s it’s unusual for some control movement to not be made in the takeoff roll. Maybe he normally set trim where he knew she would fly and just let herself fly off?

However I stand by my assertion that every once in a while even a very experienced, professional pilot can make a foolish error, one that just doesn’t make sense given their experience and past record.

But his accident video sure looks like frozen controls to me.

 

I’ve had two TW instructors in different parts of the country.  Both made me conscious of appropriate stick position to the relative wind. I was taught to keep stick back as you enter the runway environment as a continuation of appropriate elevator position to relative wind (stick forward when wind is at the tail, back when on the nose). Taking the runway stick back going  gradually forward as the throttle is opened and the tail gains adequate airflow/prop wash to come up making the transition from tail wheel steering to yaw and pitch control during the roll. I’m not a high time Tailwheel pilot (<150hrs), maybe as folks get more experience and confidence they just push everything forward and go. 
 

Agree there was a control problem.  Skeptical of the controller as a certainty. We will never know. Also agree that folks do really dumb things every now and again. Not moving the stick during taxi and take off roll doesn’t seem stupid so much as just weird.

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11 hours ago, Shadrach said:

Perhaps there are different techniques that I’ve not been exposed to, but I was always taught to start my take off roll in a taildragger with thr stick near full aft, then decreasing back pressure transitioning to forward pressure as speed builds to lift the tail.  I’ve never taken off the tail dragger with the stick in the neutral position. It’s always an exercise in maximizing Tailwheel control until transitioning control to the tail control surfaces.

Isn't it standard in a tailwheel to taxi with the stuck full aft?

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13 hours ago, A64Pilot said:

My belief is it’s often a sign of complacency, you just get real comfortable with something and forget to do something

It's also the reason for checklists used as verification. It's so easy to think in terms of familiar airplane = no need for checklist but it's a false equivalence.
 

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1 hour ago, midlifeflyer said:

Isn't it standard in a tailwheel to taxi with the stuck full aft?

Under any conditions I’d fly one, yes.  As long as the net effect of prop wash and relative wind is a headwind, stick full aft. However, strong winds at the tail during taxi could could get under an elevator in the full aft position and pitch the aircraft over on its nose, so stick forward is recommended under those conditions. 
 

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