717 certification stall test

Thanks Todd i have an old DC-9-10/30 Poh from Midway Airlines but i could never find anything about the pusher system in it, but it did explain about the limited Hydro assist on the down elevator.

It's got a pretty strong pusher system. When it kicks in you'll lose about 2500 feet in before you can get enough speed to pull the nose back up.
 
The point is that everyone seems to have an opinion about something they have little to no experience with.
If someone is unable to form an opinion or gain knowledge about something they have little to no experience with, I would consider them either intellectually disabled or intellectually dishonest. Anyone who has taken a philosophy 101 course or course on the law is familiar with the term a priori.. that knowledge which we gain with out prior experience.
 
If someone is unable to form an opinion or gain knowledge about something they have little to no experience with, I would consider them either intellectually disabled or intellectually dishonest. Anyone who has taken a philosophy 101 course or course on the law is familiar with the term a priori.. that knowledge which we gain with out prior experience.
Wait...what? I don't get it. ;)
 
Ok, so when you roll inverted, you do a split S straight towards the ground and overspeed, overstress the aircraft throw full boards and lose 10,000+ of altitude.


Or, you can do what a normal pilot should do, and just continue rolling the aircraft through the same direction it had rolled you and get your self right side up again.


And oh, this is a wake turbulence exercise? Pretty sure the NTSB came down harshly on at least one legacy airline for over-emphasizing the impact of wake turbulence on large transport category aircraft. If you're cruising along, you're not gonna flip on your back. This isn't a RJ or a Learjet.
 
If someone is unable to form an opinion or gain knowledge about something they have little to no experience with, I would consider them either intellectually disabled or intellectually dishonest. Anyone who has taken a philosophy 101 course or course on the law is familiar with the term a priori.. that knowledge which we gain with out prior experience.

How old are you, Old Pete?

In the very dark ages some fifty years ago (at a university, a college, and a seminary), to approach a subject "a apriori" was verboten. It demonstrated arrogance in forming an opinion before facts were researched and evaluated, and let personal opinion rule over objective evidence. Opinion was meant to be altered by fact, not vice-versa.

One need not personally experience something for it to mold opinion; one does need to mold personal opinion by the expertise and demonstrated experience of others, however, particularly in areas where personal experience is lacking.

Of course, language and the meaning of words is dynamic and can change subtly over time, and perhaps the concept of "a priori" is different than I learned as a strongly negative (if genuine) concept many decades ago.
 
Pretty sure the NTSB came down harshly on at least one legacy airline for over-emphasizing the impact of wake turbulence on large transport category aircraft. If you're cruising along, you're not gonna flip on your back. This isn't a RJ or a Learjet.

No, but it should would wake you up, though.
 
Ok, so when you roll inverted, you do a split S straight towards the ground and overspeed, overstress the aircraft throw full boards and lose 10,000+ of altitude.


Or, you can do what a normal pilot should do, and just continue rolling the aircraft through the same direction it had rolled you and get your self right side up again.

Assuming they departed the jet (my guess is on purpose here?), that doesn't really work. With a fully stalled wing, or even partially stalled in some cases, your ailerons aren't doing anything for you, aside from potentially making the problem worse (adverse yaw and all that)…..depending on the airframe, you might be able to do what you say with rudder/s but that can open up a whole other can of undesirable worms in a jet with a big inertia coupling tendency. Only solution is to get more airspeed over the control surfaces. Their departure wasn't this extreme, but having been in 0 airspeed or even negative airspeed/tailside departures, you are along for the ride until the stabs start working again, and a wise man still rides it out a little while longer before trying to add any roll inputs, lest you depart again.
 
Assuming they departed the jet (my guess is on purpose here?), that doesn't really work. With a fully stalled wing, or even partially stalled in some cases, your ailerons aren't doing anything for you, aside from potentially making the problem worse (adverse yaw and all that)…..depending on the airframe, you might be able to do what you say with rudder/s but that can open up a whole other can of undesirable worms in a jet with a big inertia coupling tendency. Only solution is to get more airspeed over the control surfaces. Their departure wasn't this extreme, but having been in 0 airspeed or even negative airspeed/tailside departures, you are along for the ride until the stabs start working again, and a wise man still rides it out a little while longer before trying to add any roll inputs, lest you depart again.

We're talking commercial airliners here. Why would you be stalled due to a wake encounter? You had the normal slightly positive AOA and a flip over in the 3 seconds it took doesn't mean you're now deep stalling with ineffective ailerons.
 
Much younger than Immanuel Kant. But a better question would be how catholic am I ? Not very. I know that "a priori" is a dirty word in the Catholic Church but I learned it as a college freshmen studying philosophy not as a teenager learning the catechism. If one cannot use deductive reasoning and logic to determine certain truths rather than experience I think he lacks a certain intellectual rigor.
 
I wonder how many of the critics in this thread would have reacted if they had their hand on the yoke during this.. err... maneuver. Seems like a lot of posters have the rather sensible reaction of "HOLY F***!!! ) The rest are like "yeah, he did that so wrong, I would have done it better".

How many of you guys have been in an actual 717, in any scenario, training or whatever, pointed straight down at Terra Firma? Chemicals in your brain often interfere with rational thought and all...
 
We're talking commercial airliners here. Why would you be stalled due to a wake encounter? You had the normal slightly positive AOA and a flip over in the 3 seconds it took doesn't mean you're now deep stalling with ineffective ailerons.

I must not have had the volume turned up correctly and just read the thread title……..I'd agree, if we are talking about wake turbulence, yes, you can jam the rudders and roll back upright…..at least that is what young ///AMG did the first time he was flipped upside down near BFI back in the day by said occurrence. But if we are talking about a post departure gyration, I'd say commercial airliners with clean, swept wings are more unforgiving of any hamfisting than most other types of airplanes. With that perspective and assumption, my seat cushion was firmly up the b-crack while watching them pull out, with all kinds of warning tones going off (presumably AoA and later airspeed limit)
 
We're talking commercial airliners here. Why would you be stalled due to a wake encounter? You had the normal slightly positive AOA and a flip over in the 3 seconds it took doesn't mean you're now deep stalling with ineffective ailerons.
He's not talking about a wake encounter, he's talking about this video. Regardless of what they were simulating they departed controlled flight during a stall. Not an approach to stall. I'm still wondering if you read stuff. Just curious when the last time you departed controlled flight in a swept wing jet or a 717? You seem to have such vast knowledge on multiple subjects. Please enlighten us with your knowledge. We're not talking about the wake encounter in NY in 2001 or their controversial recovery technique. We're talking about this video.
 
Just curious when the last time you departed controlled flight in a swept wing jet or a 717?
That's what I was saying... 12,000 hours of flying with the sun's shadow just casually creeping across the glareshield and then all of a sudden the sun is spinning all over the place. Complacency doesn't help hone skills. Most normal people would just react by instinct... whether right or wrong.

In this case, whatever the scenario, apparently the recovery was very successful since the plane was reusable and the only set back was that the jumpseater having to get up after it was done to track down his bag of Funions.
 
That's what I was saying... 12,000 hours of flying with the sun's shadow just casually creeping across the glareshield and then all of a sudden the sun is spinning all over the place. Complacency doesn't help hone skills. Most normal people would just react by instinct... whether right or wrong.

In this case, whatever the scenario, apparently the recovery was very successful since the plane was reusable and the only set back was that the jumpseater having to get up after it was done to track down his bag of Funions.

In this case a lot could be advanced from adopting tools from military aircraft development.

We have faced the issue of departures from controlled flight for decades and finally in our latest series aircraft with the advent of fly by wire and visual display systems we have gotten to the point where the aircraft is telling the pilot what to do and not the opposite.

You watch HUDs on modern aircraft and it's as simple as an arrow and audible commands telling you "do this stupid" for exactly the reasons your talking about.
 
He's not talking about a wake encounter, he's talking about this video. Regardless of what they were simulating they departed controlled flight during a stall. Not an approach to stall. I'm still wondering if you read stuff. Just curious when the last time you departed controlled flight in a swept wing jet or a 717? You seem to have such vast knowledge on multiple subjects. Please enlighten us with your knowledge. We're not talking about the wake encounter in NY in 2001 or their controversial recovery technique. We're talking about this video.

Good work keeping the cool, not over-G'ing the jet in general, keeping the G's symmetrical in the recovery, and making it happen. That's really all you can do. The video itself reminded me of what happens in the last 1/2 of a barrel roll when the nose digs too far below the horizon due to the roll rate being too slow on the backside
 
The video itself reminded me of what happens in the last 1/2 of a barrel roll when the nose digs too far below the horizon due to the roll rate being too slow on the backside

We called it the "barrel dive" as a T-38 IP, and was usually what happened the first time guys attempted the maneuver. It was usually followed by "I have the aircraft" in order to avoid an overspeed (hitting the number, really, since the white rocket oversped at 710KCAS) or an over-G in the recovery.

That's part of what makes me believe so strongly that airline pilots, at a minimum, need upset recovery training as part of their journey to the front end of a 121 cockpit. Better, actual aerobatic training.
 
We called it the "barrel dive" as a T-38 IP, and was usually what happened the first time guys attempted the maneuver. It was usually followed by "I have the aircraft" in order to avoid an overspeed (hitting the number, really, since the white rocket oversped at 710KCAS) or an over-G in the recovery.

That's part of what makes me believe so strongly that airline pilots, at a minimum, need upset recovery training as part of their journey to the front end of a 121 cockpit. Better, actual aerobatic training.

The barrel dive is indeed it! Throttles idle, boards, roll to the nearest horizon, stop roll, commence symmetric-G pull, remaining in limits. Enough altitude, and you're golden.
 
He's not talking about a wake encounter, he's talking about this video. Regardless of what they were simulating they departed controlled flight during a stall. Not an approach to stall. I'm still wondering if you read stuff. Just curious when the last time you departed controlled flight in a swept wing jet or a 717? You seem to have such vast knowledge on multiple subjects. Please enlighten us with your knowledge. We're not talking about the wake encounter in NY in 2001 or their controversial recovery technique. We're talking about this video.

Don't let the gun thread get to you here, leave off the personal attacks.

No airline pilot practices departure from controlled flight in a real airliner. For that matter, no one trains maneuvers in the real plane, it's all in the Level D sim.

As for this video, it's too grainy to make out many things on the PFD but it seems to flip on its back and the pilot pulls into what appears to be a split-S type dive.
 
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