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The unstallable plane that stalled

fearoflanding.com

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Re: The unstallable plane that stalled

#171

Post by bornfreddy »

Waterluvian wrote: post #46
macintux wrote: post #28

Earlier quoted context omitted.

Heck, I recently saw a video (may be an old one) of a driver who fell out of his car while showing off his acceleration. Now the entire car is an uncontrolled projectile.

Interesting that pleasure craft have dead-man switches you can optionally affix. They’re also designed to turn anti-clockwise forever if nobody is at the wheel. I guess because there aren’t seatbelts and these boats are usually open-top.

Isn't this dangerous to the person falling off (assuming no dead-man switch)? You fall off only to be run over by your own craft one turn later... It does mean that the boat won't run away far though, so there's that.

Re: The unstallable plane that stalled

#172

Post by int_19h »

hakfoo wrote: post #150
schoen wrote: post #127

Earlier quoted context omitted.

I once got to ride in an An-2 on a tourist sightseeing flight. I've always remembered the sense that the pilot didn't even bother to line up with the runway ahead of time when landing, but simply took a gentle turn onto it upon reaching it, at roughly the speed of a car. I'm sure this is a slight exaggeration in my memory, but it really was able to fly incredibly slowly and take turns in an incredibly short distance.

You'd think that sort of handling would make for some interesting use cases-- aerial photography for example, maybe some sorts of cropdusting where the slower speed offers more precision. I wonder if there's anything else built that fits that market today, since I suppose it's a hard-sell to convince Western pilots and businesses to buy Soviet old-stock.

An-2 specifically is kinda popular with Western collectors, as far as I know. But if there were still broad applications for this kind of performance, surely we'd see more modern designs along those lines?

For An-2, the ability to perform such tricks wasn't really the goal, just a side effect. The goal was to have a cheap mass-produced utility plane that could take off and land on very rough makeshift airstrips in remote locations, which were plentiful in USSR at the time when it was designed (~1950). These days there's probably way fewer locations like that, and for those that do exist, helicopters provide an adequate solution without the need to design a new dedicated airframe. Note that all those benefits aren't free, either: the downsides of the design include high fuel consumption and high noise levels.

As far as I know, even in Russia, most present-day use of An-2 is for skydiving.

Re: The unstallable plane that stalled

#173

Post by overspeed »

nickff wrote: post #63
overspeed wrote: post #15

> His opinion was that the Cessna 185 simply didn’t stall. There's your problem. Don't opine on operating characteristics of a production aircraft. Read the handbook. This incident was caused by poor airmanship.

It seems like he was asked a question which compelled him to opine. You seem to be assuming that he went ‘out on a limb’ of his own accord, without any basis for that assumption.

No, I did not make that assumption. His answer to the investigator's question should have been what the operating handbook says and not an opinion he held.

Even he was offering an opinion as addendum (that may have been edited out of context in reporting), it shouldn't be this one.

Re: The unstallable plane that stalled

#174

Post by HeyLaughingBoy »

user_7832 wrote: post #62
lettergram wrote: post #10

Earlier quoted context omitted.

My reflex is to never mandate safety procedures. To put it simply, why should the state use force to mandate something like safety. The implication being if someone refuses the force of the state is used on them… which is definitely not good or improving safety. Mandating the seatbelts exist, sure. Mandating people wear them? Idk about that. In the case of tractors for instance, wearing a seatbelt is downright danger…

> In the case of tractors for instance, wearing a seatbelt is downright dangerous. You cannot jump out then, and will be killed by a tractor if it flips. The "proper" solution would be to have a rollcage so that even a flipped tractor does not crush its occupants. Not having a roll cage (presumably to save $) is a result of weaker/less mandated safety procedures already. Cars have a roof crush test. The solution isn'…

I believe that Rollover Protection Systems (ROPS) have been mandatory on new tractors up to a certain weight for quite some time now.

Re: The unstallable plane that stalled

#175

Post by Zak »

analog31 wrote: post #144
the__alchemist wrote: post #24

Soapbox: Stall speed is an approximation. It's baffling that GA aircraft don't have one of the most safety-critical measurements: AOA. Stall airspeed varies with a number of factors; this includes the mods described in the article, and weight change from burning fuel, passengers, payload etc. AOA is more invariant to that as a metric for choosing stall speed, speed down final etc.

I'm not a pilot, but now I'm curious. What do you actually do if the plane stalls, or is about to do so? Other than die?

To add to what Toutouxc said, stalls are a fairly routine training/familiarization maneuver in most light aircraft. The typical recovery is just to push forward on the stick/yoke. A manual[0] I found with a web search claims a Cessna 185 on floats may require up to 200 feet to recover.

Stalling one wing but not the other usually results in a spin, for which recovery requires both breaking the stall and stopping the rotation. The ailerons, located near the wingtips are not effective (or even counterproductive) during a spin because air is not flowing smoothly over the stalled wing; the rudder, located on the tail is used to stop the rotation. This usually requires more altitude for recovery.

If you stall one wing but not the other at an altitude of 15 meters (49 feet), it's very likely you're going to contact the surface in a manner you did not intend. Inappropriate control inputs, such as trying to correct the resulting bank using the ailerons guarantee it. It's still a good idea to attempt to recover rather than sit still and pray because a more controlled impact is usually more survivable.

[0] https://aerocet.com/uploads/A-10010.pdf

Re: The unstallable plane that stalled

#176

Post by ultrarunner »

KennyBlanken wrote: post #137
ultrarunner wrote: post #53

Earlier quoted context omitted.

Soapbox next to your soapbox: GA planes are old specifically because of the FAA and their overly restrictive regulations. The cost involved to create an AoA sensor & readout is minimal and at least one company has done it with an IMU only. The cost to certify, sell, and install an AoA sensor (in terms of both money and time waiting to get on the schedule of an FAA-blessed installer) is more than most people find it t…

The FAA is stuck in the 60's because there is a massive industry supporting the ancient technologies in general aviation. Modern stuff, like you point out, is far more reliable, cheaper, lower power consumption, and more functional. That better reliability means less need for aircraft mechanics and avionics shops. Nobody would want their discreet component transponder overhauled if it could be replaced with a cheaper…

This type of protectionism is exactly what I was referring to above. It's the single most frustrating aspect of aviation.

Re: The unstallable plane that stalled

#177

Post by datascienced »

psunavy03 wrote: post #166
datascienced wrote: post #153

Earlier quoted context omitted.

Although can you recover at a height 15m above terrain?

. . . probably not, but does that mean you never practice? Most stall/spin incidents occur at low altitude, but not THAT low. It's often pilot inattention in the landing pattern.

I agree! IANAP though.

Also in this case I suspect they needed to learn proper takeoff procedure. Since you can’t practice dying more than once the mitigation has to be avoidance (in addition to the stall practice you mentioned)

Re: The unstallable plane that stalled

#178

Post by fransje26 »

jcalvinowens wrote: post #168
fransje26 wrote: post #162

Earlier quoted context omitted.

> An experienced pilot can feel the stall coming on with a bit of a "burble" in the stick. Without any disrespect to the flying abilities of your Dad, as an aerospace engineer, the short answer to that is "no". You will have the luck to feel a "burble" if the airplane has been been built to be give you that warning. You have absolutely no guarantee that once the airplane has been modified beyond its original configur…

> You will have the luck to feel a "burble" if the airplane has been been built to be give you that warning. Airplanes which are designed to do this (most airplanes) do it very reliably, it's not luck. Several of the Citabrias I fly don't have stall horns, all I have is the buffet. Complexity is always a tradeoff: it's harder to fuck up building and/or repairing a simpler airfoil.

> Several of the Citabrias I fly don't have stall horns, all I have is the buffet.

That's fine, as long as the airfoil and wing planform you chose have a forgiving-enough lift vs angle-of-attack curve that you get plenty of buffeting before you start loosing significant lift and fall out of the sky.

> Airplanes which are designed to do this (most airplanes) do it very reliably

Yes, this is by design. Enough pilots were killed because their planes were not doing this reliably, and they literally fell out of the sky.

Re: The unstallable plane that stalled

#179

Post by fransje26 »

I_Am_Nous wrote: post #167
fransje26 wrote: post #162

Earlier quoted context omitted.

> An experienced pilot can feel the stall coming on with a bit of a "burble" in the stick. Without any disrespect to the flying abilities of your Dad, as an aerospace engineer, the short answer to that is "no". You will have the luck to feel a "burble" if the airplane has been been built to be give you that warning. You have absolutely no guarantee that once the airplane has been modified beyond its original configur…

Is it possible there's a mechanical/design cutoff where most planes designed to be fully mechanical would feel the "burble" while a more modern plane would not, similar to ABS vs non-ABS brakes or powersteering vs none? Are there hydraulic assists for flight controls that might smooth out those mechanical tells?

Not necessarily, no.

It's a design feature to give pilots an advanced, physical warning that they are about to stall, and fall out of the sky. Electronic systems are all nice an well, but they can fail. So why not simply make it a physical feature of your airplane design, that triggers reliably not matter what?

In some very specific edge cases a designer might decided that the planform trade-offs needed to bake the feature into the wing is not worth the performance loss in other metrics, and might forgo a nice, buffeting pre-stall wing. But plenty of pilots have died because they unexpectedly stalled, so it is not a design decision that should be taken lightly.

Re: The unstallable plane that stalled

#180

Post by psunavy03 »

datascienced wrote: post #177
psunavy03 wrote: post #166

Earlier quoted context omitted.

. . . probably not, but does that mean you never practice? Most stall/spin incidents occur at low altitude, but not THAT low. It's often pilot inattention in the landing pattern.

I agree! IANAP though. Also in this case I suspect they needed to learn proper takeoff procedure. Since you can’t practice dying more than once the mitigation has to be avoidance (in addition to the stall practice you mentioned)

Technically, power-on stalls are supposed to teach how to recover from bad technique on takeoff/go-around and power-off stalls are supposed to teach how to recover from bad technique in the landing pattern.

In reality, they're both training-wheels versions of how to deal with any departure from controlled flight, which is why any professional pilot worth their salt should have a decent grounding in aerobatics and some spin/departure/out-of-control flight experience.

-Am (or at least was) a pilot . . . I could jump in and fly a bugsmasher today if I really needed to, just not legally without a doc visit and a checkride.

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