What happened to the "impossible turns" thread?
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What happened to the "impossible turns" thread?
It had all the potential for a good discussion, although it would probably overlap a bit (maybe a lot) with the EFATO thread.
You didn't delete it, n5296s, did you?
Fortunately I still have it cached here...
You didn't delete it, n5296s, did you?
Fortunately I still have it cached here...
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Annoying. I spent around 15 minutes writing, checking, editing and re-editing my response. That work was dumped in the bit bucket as well.
On the other hand, if you write this to someone:
And then you're proven wrong, I can imagine people do not want to have that preserved for eternity.
On the other hand, if you write this to someone:
I'd suggest you stick to the simming and leave flying to people who know what they're talking about.
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Looking at the EFATO thread, it seems to include discussion on the Rogers report, so it could well be the author realised and deleted his thread. Either that or we got trolled!
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That was my first thought... That the threads may have been merged. But they're not.
And the angle in this one was different. This one was about someone who practiced an EFATO turn-back in his own aircraft (kudos for that) and found out that 500' was possible using a technique with which he was comfortable.
But in the course of his explanation we found a fundamental flaw in his reasoning and aerodynamic understanding. We tried to correct that but he wouldn't have any of it, apparently.
And the angle in this one was different. This one was about someone who practiced an EFATO turn-back in his own aircraft (kudos for that) and found out that 500' was possible using a technique with which he was comfortable.
But in the course of his explanation we found a fundamental flaw in his reasoning and aerodynamic understanding. We tried to correct that but he wouldn't have any of it, apparently.
Hmm... As somebody who only saw the first half of his thread, I'd have been keen to see where the rest of the conversation went if there was a serious flaw in his reasoning.
It was deleted by the originator.
I must admit, as a Pprune regular of lots of years standing, that always annoys the heck out of me. When other people have put a lot of effort into crafting constructive replies to something, and there are no personal attacks on anybody, it strikes me as very poor manners.
Backpacker - I've moved your long and really quite helpful post from the deleted thread into the EFATO thread. You might want to tweak it slightly as it refers to some other posts I've not copied over.
G
I must admit, as a Pprune regular of lots of years standing, that always annoys the heck out of me. When other people have put a lot of effort into crafting constructive replies to something, and there are no personal attacks on anybody, it strikes me as very poor manners.
Backpacker - I've moved your long and really quite helpful post from the deleted thread into the EFATO thread. You might want to tweak it slightly as it refers to some other posts I've not copied over.
G
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When other people have put a lot of effort into crafting constructive replies to something, and there are no personal attacks on anybody, it strikes me as very poor manners.
On balance, I think the feature of p p r u n e whereby the starter can delete a thread which has been thus hijacked is a good thing.
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GtE, when a thread is deleted, by the Op or by mods (or by any other way, if there is one), does it still reside somewhere you can get at it? If so, for how long?
(No agenda, just interested on the process, if you don’t mind sharing it with us.)
Chris N.
(No agenda, just interested on the process, if you don’t mind sharing it with us.)
Chris N.
Usually there are, however, personal attacks, or moves by certain individuals to broaden the debate into areas where the original poster did not intend to go, and those individuals are well aware that the OP does not want to go there (a common reason might be that he doesn't want to identify certain individuals).
On balance, I think the feature of p p r u n e whereby the starter can delete a thread which has been thus hijacked is a good thing.
On balance, I think the feature of p p r u n e whereby the starter can delete a thread which has been thus hijacked is a good thing.
De facto, he's stolen from those later posters the time they put into posting, constructing discussion which contained stuff they felt was worth saying, and might have created valuable discussion for other people. Even if it was off topic.
So, yes I agree that the feature should exist, but equally don't like the abuse that one or two people have made of it simply because they didn't like thread drift or the fact that some opinions differed from theirs.
G
Yes, I deleted it. Sue me. Despite Genghis's peeved reply, it seems that the content is retained and therefore nobody has stolen anything.
Actually I was in the middle of writing a long reply about why there is NOT a fundamental misunderstanding of aerodynamics in what I wrote when my browser decided to delete the whole window. At which point I thought, screw it, this thread has been hijacked by a bunch of people who seem to take a perverse pleasure in being patronising just for the sake of it, and seem seriously irony-challenged to boot. So why bother? "Stealing" backpacker's inaccurate and patronising reply gave me a brief moment of pleasure, of which I am not ashamed.
So, just for the record:
-- whether you are climbing or descending does NOT affect the load factor on the wing. Only CHANGES in vertical speed do. If you are in a steady bank at a steady vertical speed, the load factor is sec(angle of bank) and that's all there is to it. People who think otherwise should definitely stick to simming.
-- precisely BECAUSE you can't really fly a bank angle to 1% accuracy, I prefer to have a bit of margin in EITHER the speed I'm flying OR altitude. Since the latter is impossible with this manouver, I went for speed.
-- one of bp's patronising remarks was "clearly you have no experience of aerobatics". I have 120 hours flying acro in the Pitts, with manouvers of all levels up to unlimited. I do know what an accelerated stall is.
My original post was written with the intent of "people often ask questions about this, I went and did it, in case anyone's interested, here's what happened". Unlike others, I wasn't trying to show how smart I am or what a superior pilot I am or what an inferior pilot (or aerodynamicist) everyone else is.
Mods, feel free to ban me - it'll be a while before I'm back.
Actually I was in the middle of writing a long reply about why there is NOT a fundamental misunderstanding of aerodynamics in what I wrote when my browser decided to delete the whole window. At which point I thought, screw it, this thread has been hijacked by a bunch of people who seem to take a perverse pleasure in being patronising just for the sake of it, and seem seriously irony-challenged to boot. So why bother? "Stealing" backpacker's inaccurate and patronising reply gave me a brief moment of pleasure, of which I am not ashamed.
So, just for the record:
-- whether you are climbing or descending does NOT affect the load factor on the wing. Only CHANGES in vertical speed do. If you are in a steady bank at a steady vertical speed, the load factor is sec(angle of bank) and that's all there is to it. People who think otherwise should definitely stick to simming.
-- precisely BECAUSE you can't really fly a bank angle to 1% accuracy, I prefer to have a bit of margin in EITHER the speed I'm flying OR altitude. Since the latter is impossible with this manouver, I went for speed.
-- one of bp's patronising remarks was "clearly you have no experience of aerobatics". I have 120 hours flying acro in the Pitts, with manouvers of all levels up to unlimited. I do know what an accelerated stall is.
My original post was written with the intent of "people often ask questions about this, I went and did it, in case anyone's interested, here's what happened". Unlike others, I wasn't trying to show how smart I am or what a superior pilot I am or what an inferior pilot (or aerodynamicist) everyone else is.
Mods, feel free to ban me - it'll be a while before I'm back.
You won't get banned "n" - I may be a moderator, but I was simply expressing an opinion.
A few people have deleted threads recently, on grounds that personally I didn't agree with. I reserve the right to express an opinion about that (or about aerodynamics!), and that right of-course belongs to everybody else around here too, so long as they're polite and impersonal about it.
G
A few people have deleted threads recently, on grounds that personally I didn't agree with. I reserve the right to express an opinion about that (or about aerodynamics!), and that right of-course belongs to everybody else around here too, so long as they're polite and impersonal about it.
G
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I absolutely agree that there need to be mechanisms for weeding out personal abuse (although I can't say I could see any in the deleted thread), but alternately consider say that somebody spends 2 minutes posting a brief comment, it drifts somewhat, and several other people have spent 20+ minutes each constructing some detailed discussion which people are getting a lot out of. However, the OP decides that these lengthy posts aren't what he wanted to talk about at-all, so deletes the thread.
De facto, he's stolen from those later posters the time they put into posting, constructing discussion which contained stuff they felt was worth saying, and might have created valuable discussion for other people. Even if it was off topic.
De facto, he's stolen from those later posters the time they put into posting, constructing discussion which contained stuff they felt was worth saying, and might have created valuable discussion for other people. Even if it was off topic.
My remark was not patronising in the least. It was most definitely insulting (assuming the poster was NOT a simmer), but not patronising. The first patronising remark was in the very first reply. I guess on reflection it was more nanny-knows-best than truly patronising, but definitely in that general area.
Actually I remain to be convinced that "Mark1234" is NOT a simmer and a flying wannabe, having taken a look at some of his other posts. But maybe it's just the way he writes.
Actually I remain to be convinced that "Mark1234" is NOT a simmer and a flying wannabe, having taken a look at some of his other posts. But maybe it's just the way he writes.
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It was most definitely insulting
But with an attitude like that, where you apparently deliberately chose to insult people, I don't think it's worth it.
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I was actually looking forward to the development of the latest "impossible turn" post. To me, there are two distinct considerations.
Firstly, is it possible? This depends on many variables. To quote a few: height, still air range from the runway, length of runway, wind, aircraft capability/performance.
Secondly, and probably equally/more relevant, the reaction of the pilot. I occasionally demonstrate the "impossible turn", showing that, under certain circumstances, it is quite possible. But then I point out that pilots are not perfect and when faced with a real engine failure their performance may well degrade beyond the point of successfully completing a relatively challenging manoeuvre.
Anecdotally, there are a number of fatal accident reports whereby pilots appear to have tried to turn back towards the airfield. I'm not aware of a similar, or indeed greater, number of incident reports indicating successful engine failure turnbacks.
One final point. I would have thought that a pilot with a significant number of hours on an aerobatic aircraft would have graduated beyond using airspeed as an indication of AoA (proximity to stall). Indeed, the reliance on the ASI during steep turns, especially when close to the ground, rather worries me.
Firstly, is it possible? This depends on many variables. To quote a few: height, still air range from the runway, length of runway, wind, aircraft capability/performance.
Secondly, and probably equally/more relevant, the reaction of the pilot. I occasionally demonstrate the "impossible turn", showing that, under certain circumstances, it is quite possible. But then I point out that pilots are not perfect and when faced with a real engine failure their performance may well degrade beyond the point of successfully completing a relatively challenging manoeuvre.
Anecdotally, there are a number of fatal accident reports whereby pilots appear to have tried to turn back towards the airfield. I'm not aware of a similar, or indeed greater, number of incident reports indicating successful engine failure turnbacks.
One final point. I would have thought that a pilot with a significant number of hours on an aerobatic aircraft would have graduated beyond using airspeed as an indication of AoA (proximity to stall). Indeed, the reliance on the ASI during steep turns, especially when close to the ground, rather worries me.
number of incident reports indicating successful engine failure turnbacks.
My only goal in doing this was to find MY personal minimum in MY plane (I will not be trying this in the Pitts!), and to have experience doing it in a low-stress context so if it ever really happens I won't be thinking "gee, I wonder if this works".
graduated beyond using airspeed as an indication of AoA
In any case there are much better indications of stall than any of this - though the 182 (mine anyway) has very little buffet, unlike the Pitts. Keeping airspeed way above the theoretical stall speed is just a handy way to avoid the problem. And I can recover a stall in less than 100', but I'd rather not be put to the test at 101' AGL if I can avoid it.
I confess to being baffled by this recurring statement that bank angle does not in itself tell you stall speed, in a steady state. One now-deleted and unmissed post said something about "stall speed could be anywhere from 40-80 knots at 45 degrees of bank" (for an aircraft whose Vs is 50 knots). I'm a pilot, not an aerodynamicist, so it's possible that the greatly oversimplified elementary texts I consult (e.g. Aerodynamics for Naval Aviators) chose to miss out something important, I guess. I'd like to know what it is.
So, let's try this one more time. In a steady bank at a steady horizontal and vertical airspeed, stall speed = sqrt(sec(angle of bank)) * (straight and level stall speed in the same configuration). What is the missing "mystery factor" that makes this not true?
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What would you suggest using, in a plane that doesn't have an AoA indicator (i.e. 99.99% of them)?
Another person cheesed off that this thread was pulled after putting effort into a reply!