Hawker 900XP down, 2/7/24

Interpolating here…. But your math checks out, Steve.View attachment 76503
Total sidebar:

I think this poorly-conceived image has probably killed people, especially in the form where it's extrapolated and used for "stall speeds."

The load factor is not induced by the turn in this image, but by the application of elevator backpressure. The same load factor would be induced by the same backpressure in level flight.

You're loading the wing with the elevator. There is no load induced by the turn itself.

It causes fundamental misunderstanding of aerodynamics that takes a lot of work to fix. (I've worked to help quite a few people over the years who thought they understood turning aerodynamics and were shocked to find that they didn't.)

I know everyone here knows this, but I want to point out how bad this image (and caption) tangles up people who haven't developed a solid understanding of aerodynamics yet.
 
I love this gem…



Yup. Hitting wake turbulence that rolls you 10 degrees from inverted is a non-issue.
Yes, and:

To be clear, if you pass 90°, you're in the inverted flight regime. If you attempt to maintain level flight, it will require forward elevator pressure and opposite-bank rudder in turns (in addition to a significant increase in AoA in a non-symmetrical airfoil, plus uh ... inverted-capable fuel and oil systems).
 
I just declined my company request to do a stall test on our hawker 900. I have done one in the past when young and dumb. No more. I have been told that the stall test is docile until it is not. Once it is not then it is major and I have been told it may take over 20,000 feet to recover.

Yes hawker stall tests a commonly required. Any time the leading edge comes off. Also the leading edge must come off to do any tks work in the wing.
Hawker stall tests are mostly to verify handling characteristics after the stall trigger is removed/ replaced or is a certain number of leading edge pannels are removed - so you have to do it after C check etc.

It's a published procedure - you do it in all configurations - the setup is scripted, slowing at a rate of 1kt per second. Looking for a clean entry to stall and not settling into a descending stall. All you are really looking for is the ability to correct any roll tendencies with aileron input. If you are able to keep the roll within limits, it's successful, and you are looking for the calculated speeds to match the actual speeds in the plane.

The one that gets you is the full flaps. The airplane really wants to mush and then falls off to one side pretty quickly. I did them several times but only had one unsuccessful event. Upset recovery is kind of a prerequisite to doing these... however, recovery from the upset is pretty easily achieved so long as you don't do the wrong thing. There is a better-than-average chance you'll overspeed if it goes poorly, however.

I'd be ok doing them again if I was currently in the plane still - If you know that you will be doing them, pay close inspection to the panel and trigger alignment, make sure the sealant isn't bulging from the edges and that there are no wear or tool makes which indicate something isn't where it has been for the rest of its life.

Pulling a single panel for TKS work doesn't usually result in stall tests. If I recall correctly, was it 3 panels removed? it's been a while.

Re- this accident - I don't think 20,000 feet is in the envelope; if I recall, it was 15,000+/- a few... This one was at 20k.. so I'm not sure.

I almost always did them en route on the way home from MX; however, if the test was successful, I continued home and signed the log book off.
 
Total sidebar:

I think this poorly-conceived image has probably killed people, especially in the form where it's extrapolated and used for "stall speeds."

The load factor is not induced by the turn in this image, but by the application of elevator backpressure. The same load factor would be induced by the same backpressure in level flight.

You're loading the wing with the elevator. There is no load induced by the turn itself.

It causes fundamental misunderstanding of aerodynamics that takes a lot of work to fix. (I've worked to help quite a few people over the years who thought they understood turning aerodynamics and were shocked to find that they didn't.)

I know everyone here knows this, but I want to point out how bad this image (and caption) tangles up people who haven't developed a solid understanding of aerodynamics yet.

Yes ma’am… I was just looking for a picture that had a bank angle depicted with some degrees that’s all.
 
New math or something?

360 degrees = all the way around, 180 degrees = upside down, yes?
Ok, excellent call! Mea culpa. You're absolutely right. My wee, addled brain was confused. I think... maybe... I was "thinking" half-way to fully inverted. Probably due to too many beers and oxy deprivation from a long day. But, no excuses! Either way, I was wrong. You are correct. And, I sit corrected.

Also, all you other inattentive scrows who are now glomming onto the pile due to @SteveC 's insightful observation and critique. Well, you know what y'all can do. Notice yer own anomolies... don't steal others'.
:)
 
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I fall down a lot, have been in a couple brawls in years gone by where I shouldn't have been, and just got old, generally, where some stitches (and I did that one time personally - not at all recommended) were required. I try to ignore mirrors, too, with varying degrees of success.

Believe it or not, my worst visit to urgent care was for removal of an embedded tick in a very personal place I could neither see nor excise. I felt badly for the nurse who accomplished the task but more embarrassed for the process required. I hope never to have a tick that requires the same of me in a location such as that, whatever the professionalism of the caregiver🤷‍♂️

I'm still going to use the quote in different places as circumstances permit, if you don't mind. If you do, I'll respect your preference.
Mirrors are a bitch. Everything is backwards. Very difficult to do a home appendectomy via mirror. Kinda the same reason we should stop seeking to go back to some imagined "past of glory", and instead move ahead, smarter than we were back then. Going backward is only ever going to be a losing proposition - whether civilizationally or appendectomally.

There's a decent (albeit war-aggrandizing) movie called "We Were Soldiers Once, And Young". They kind of messed up that title. It should have been "We Were Young Once, And Soldiers". That way, folks would perhaps realize that the young are oft inveigled into answering stupid asks simply as a function of their youth and innocence and, consequent, ignorance.
 
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The load factor is not induced by the turn in this image, but by the application of elevator backpressure. The same load factor would be induced by the same backpressure in level flight.

I know everyone here knows this, but I want to point out how bad this image (and caption) tangles up people who haven't developed a solid understanding of aerodynamics yet.
NO. You don't (and you know that you don't)! That's precisely the problem. That's precisely why you scribed your excellent -yet seemingly unnecessary- post.
 
I love this gem…



Yup. Hitting wake turbulence that rolls you 10 degrees from inverted is a non-issue.
That's actually pretty damned funny. Just sad that you didn't suss it yourself and had to rely on @SteveC to give you your bullets.

Well piled! Are you a very heavy person who adds lots of weight at the top of the pile and squishes both your friends AND the poor sot at the bottom? Did you do that to the nerds during the football section of HS gym class, too? Well done, you brilliant, observant person, you!
 
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Woah let's stop the train for a second. I'm not like *entirely* convinced that most working pilots don't understand basic aerodynamics. I mean sure, you definitely get your outliers who treat it as a Dunken-Hines cake mix recipe (follow the directions, press the right buttons, and you get a nice cake, no need to understand how it works). But I'd put pretty good money down that 95%+ of the people I fly with understand in a basic sense that they're "flying the wing(s)".

It's popular and, what, "click-baity" to rail against the dying of Teh Fundamentals, etc. etc., but I haven't really seen much of that on the line, at least to the extent that it's obvious one way or the other.

I *have* seen a fair amount of complacency, and I'm sure I'm guilty of that myself. You (whoever you are) may be as well. But not understanding that the wing stalls when it's loaded up (whichever way the aircraft is pointed relative to the horizon)? Ehhhhh. I can count on one hand (ok maybe two hands) the number of times I've flown with someone who I would even *suspect* of that in *counts on fingers* 30ish years of operating the aviation appliances. Maybe I've just been lucky?

Or maybe this is just a weeee bit of confirmation-bias fueled by watching too much YouTube and a slightly negative attitude regarding These Danged Kids.

OTOH, their music does suck. There's no rational argument there.
 
Woah let's stop the train for a second. I'm not like *entirely* convinced that most working pilots don't understand basic aerodynamics. I mean sure, you definitely get your outliers who treat it as a Dunken-Hines cake mix recipe (follow the directions, press the right buttons, and you get a nice cake, no need to understand how it works). But I'd put pretty good money down that 95%+ of the people I fly with understand in a basic sense that they're "flying the wing(s)".

It's popular and, what, "click-baity" to rail against the dying of Teh Fundamentals, etc. etc., but I haven't really seen much of that on the line, at least to the extent that it's obvious one way or the other.

I *have* seen a fair amount of complacency, and I'm sure I'm guilty of that myself. You (whoever you are) may be as well. But not understanding that the wing stalls when it's loaded up (whichever way the aircraft is pointed relative to the horizon)? Ehhhhh. I can count on one hand (ok maybe two hands) the number of times I've flown with someone who I would even *suspect* of that in *counts on fingers* 30ish years of operating the aviation appliances. Maybe I've just been lucky?

Or maybe this is just a weeee bit of confirmation-bias fueled by watching too much YouTube and a slightly negative attitude regarding These Danged Kids.

OTOH, their music does suck. There's no rational argument there.
I call BEEE ESSS on that. At least the 95% statistical expectation. I'd call it more like, maybe 50%. Kinda off to one side of the bell curve.

The way pilots are "trained" these days is very similar to how McDonald's "trains' burger flippers. Mostly rote. No one really cares; We need asses in seats. FAA be all like, we'll get 'em later for bad paperwork. Hell, man, most "pilots" these days don't even know what a rudder even is.

If there really IS a supply-chain problem right now, it's the delay in the delivery of "give-a-poop-tablets". Both 50 and 100 mg.
 
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I call BEEE ESSS on that. At least the 95% statistical expectation. I'd call it more like, maybe 50%. Kinda off to one side of the bell curve.

I don't see how someone gets through EET training (for all of its limitations) without understanding how a wing works *shrug*. Maybe I'm not seeing the whole picture, since I mostly fly with people as Old (or Older) than myself, dunno. I suppose it's possible that at the dreaded Regionals (or 135 Charter, etc.) everyone is getting by on luck, but they sure don't seem to be tumbling out of the sky like shot pigeons all over the place.
 
I don't see how someone gets through EET training (for all of its limitations) without understanding how a wing works *shrug*. Maybe I'm not seeing the whole picture, since I mostly fly with people as Old (or Older) than myself, dunno. I suppose it's possible that at the dreaded Regionals (or 135 Charter, etc.) everyone is getting by on luck, but they sure don't seem to be tumbling out of the sky like shot pigeons all over the place.
For a variety of messed up reasons, I get to interact with the new hires at a particular airline. I'm very concerned. I'm really not meaning to be an arrogant, condescending ass-hat. I just see what see. It's freaking scary.

Real pilots should NOT be trained by rote. Their job is not to flip the switches in the correct order for the correct amount of time. Their job is to be able to continue to fly the airplane while fixing the stuff that just broke. It's ALL automation these days. Right up until it's NOT. Only then do you really even need a pilot.
 
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For a variety of messed up reasons, I get to interact with the new hires at a particular airline. I'm very concerned. I'm really not meaning to be an arrogant, condescending ass-hat. I just see what see. It's freaking scary.
Fair enough. Guess I'll just be grateful that my yob hires grandpas and grannies. And maybe start sleeping in the basement.
 
I *have* seen a fair amount of complacency, and I'm sure I'm guilty of that myself. You (whoever you are) may be as well. But not understanding that the wing stalls when it's loaded up (whichever way the aircraft is pointed relative to the horizon)? Ehhhhh. I can count on one hand (ok maybe two hands) the number of times I've flown with someone who I would even *suspect* of that in *counts on fingers* 30ish years of operating the aviation appliances. Maybe I've just been lucky?

Or maybe this is just a weeee bit of confirmation-bias fueled by watching too much YouTube and a slightly negative attitude regarding These Danged Kids.

OTOH, their music does suck. There's no rational argument there.
It ain't "those danged kids". Many of "those danged kids" are terrific. Some few are outstanding and, having just come from real engagement in a good training environment, know more of the minutia than I recall anymore.

I'm talking statistical norms, not about the outliers.

Also, I fly about 50% of my working flights SP, so my problem is typically not complacency (yet, truly, we are ALL susceptible). So, you know, my problem is usually overload.
 
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If you want to feel scared about the newer generation of pilots, watch a little YouTube.

Person was flying IFR, iPad died, "couldn't fly an approach"
Influencer kept trying to fly a Bonanza like it had autothrust and got kilt dead.
Student pilot clearly never worked the radio without much coaching and gets the flight basically cancelled and told to taxi back to the gate.
The title of the video mentions "hilarious" but it's tremendously concerning because who the hell is instructing has been instructing this pilot!?
View: https://www.youtube.com/watch?v=XBb0r8aLOYM
 
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