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The unstallable plane that stalled

fearoflanding.com

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Re: The unstallable plane that stalled

#31

Post by hluska »

macintux wrote: post #26
jcalvinowens wrote: post #17

It is not necessary to empirically determine a specific airplane's stall speed in order to operate it safely. It's not required in the US, we just use the number the manufacturer publishes. It's normal for airplanes of the same model to fly differently: I fly a little fleet of six Citabrias, and their stall characteristics are radically different. You'd expect more uniformity from a modern aluminum airplane, but stil…

I'll admit to complete and total ignorance, but: > ...we just use the number the manufacturer publishes. From the article it sounds like this plane was radically modified, to the point where the manufacturer's stall speed would be irrelevant. Why wouldn't you want to confirm for yourself where the speed is after so many changes?

The plane had a cargo pack and a Robertson STOL. Cargo packs are essentially for bush planes and as an example, the 1975 Skywagon’s owners manual even had one diagrammed. Robertson STOL’s are extremely common in Northern Canada to the point that even as a passenger I know about them.

It’s nothing too radical.

Edit - Here’s a copy of the 1975 owners manual:

https://www.seaplanescenics.com/documents/1975-cessna-185f-p...

Re: The unstallable plane that stalled

#32

Post by jcalvinowens »

macintux wrote: post #26
jcalvinowens wrote: post #17

It is not necessary to empirically determine a specific airplane's stall speed in order to operate it safely. It's not required in the US, we just use the number the manufacturer publishes. It's normal for airplanes of the same model to fly differently: I fly a little fleet of six Citabrias, and their stall characteristics are radically different. You'd expect more uniformity from a modern aluminum airplane, but stil…

I'll admit to complete and total ignorance, but: > ...we just use the number the manufacturer publishes. From the article it sounds like this plane was radically modified, to the point where the manufacturer's stall speed would be irrelevant. Why wouldn't you want to confirm for yourself where the speed is after so many changes?

My understanding is that in the US, part of the modification would be updating the plane's official operating limitations, and there could be a new stall number. Still a number from the manufacturer, not a number empirically determined by testing that specific airplane. For special one-off modifications, I don't know: I've always been told that's almost impossible with certified airplanes.

One Citabria I've flown had vortex generators installed on the leading edge of the wings, but the club sold it over a year ago and I don't remember if it listed a modified stall speed. I do remember it said "not airworthy if more than N of the VGs are broken off", I think it was three?

Re: The unstallable plane that stalled

#33

Post by roywiggins »

lettergram wrote: post #10
travisjungroth wrote: post #5

Earlier quoted context omitted.

It sounds like the two surviving passengers would have died if they had life jackets on. I can’t imagine getting out of an inverted, flooded 185 cabin with a life jacket on. I think there was some sense to not requiring life jackets on seaplanes. They’re much more confined spaces than most pleasure boats, not to mention that you’re usually on a boat rather than in it. The flooding is also usually just about instant a…

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…

Everyone ends up paying for that, in the form of insurance rates.

Re: The unstallable plane that stalled

#34

Post by Tuna-Fish »

cjbgkagh wrote: post #21
golergka wrote: post #11

Earlier quoted context omitted.

Edit: It seems that I completely misread what Wikipedia said, disregard this comment.

Over 18k An-2 were produced during the time of 1947-2001. It’s an unusual plane due how old it is and that many are still in operation so general stats should take that into account. It’s well known for being nearly impossible to stall with a stall speed of 30 knots - if it does stall it’ll sink at the rate of a parachute which is still faster than you’d want to hit the ground for a landing. It’s also easy to pick up…

Wasn't AN-2 the plane where the manual advises that if you need to land and cannot see your landing site, you should fly low and slow and intentionally stall the plane?

Re: The unstallable plane that stalled

#35

Post by sumofproducts »

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 was very skeptical of this until I had the chance to fly one of those brand-new C172 models that come equipped with 'em. They're so convenient!

Sure, ye olde haptic feedback + inner ear + stall horn/shaker combo has always worked for me—but if you are a new or overwhelmed or complacent or unlucky pilot, having a big angry indicator sitting atop the glare shield furiously (visually & audibly) informing you of the approaching cross-control stall that is about to bury you in your base-to-final grave makes danger IMPOSSIBLE to miss.

The LEDs were bright enough to be clearly visible even under direct sun, but the Geiger-esque clicking and chattering increasing in urgency as I approached critical AoA made it for me. No need to put your head down or even alter your scan to include it: you can hear trouble coming!

Re: The unstallable plane that stalled

#36

Post by hinkley »

jcalvinowens wrote: post #17

It is not necessary to empirically determine a specific airplane's stall speed in order to operate it safely. It's not required in the US, we just use the number the manufacturer publishes. It's normal for airplanes of the same model to fly differently: I fly a little fleet of six Citabrias, and their stall characteristics are radically different. You'd expect more uniformity from a modern aluminum airplane, but stil…

Decreases the stall speed? How does that work?

Re: The unstallable plane that stalled

#37

Post by eesmith »

andrewaylett wrote: post #23
Waterluvian wrote: post #2

Life jackets seem like they’d be problematic in an enclosed cabin where their use is if you’ve crashed and are taking on water. That’s a bit different compared to a pleasure craft or other vessel that has an outside deck and likely more time to react. But I don’t really know things. Perhaps most float plane emergencies that require life jackets don’t suffer from my perception of the issue.

In my vernacular, I distinguish between "life jackets" and "buoyancy aids". Apparently most people don't. A buoyancy aid has a foam core, and always provides buoyancy. It's the sort of thing you'd wear while kayaking, but it's far too bulky to want to wear it unless you expect to go in the water. A life jacket is inflatable, and normally automatic. If you're at risk of falling in, and to do so would be dangerous, you…

Which vernacular is that?

In boating a life jacket does not need to be inflatable. https://uscgboating.org/recreational-boaters/life-jacket-wea... says:

> There are four basic design types: Inherent, Inflatable, Hybrid, and Special Purpose.

> There are two main classes of PFDs.

> * Those which provide face up in-water support to the user regardless of physical conditions (lifejackets).

> * Those which require the user to make swimming and other postural movements to position the user with the face out of the water (buoyancy aid).

It mentions both "Foam filled lifejackets" and "Inflatable lifejackets".

Re: The unstallable plane that stalled

#38

Post by hinkley »

talkingtab wrote: post #25

Non sequitur from non-pilot: I was once in Duluth, MN in the bitter cold and watched a Cessna with skis (for landing on the frozen lakes of the Boundary Waters) land at the airport. It was the utterly bewildering to see how slowly it was going in the air. And how little distance it took to stop. Short Landing Kit I assume. I've seen ducks and geese come into land on lakes at higher speeds!

Some of those Cessnas have a stall speed so low they can fly backward on a windy day.

Re: The unstallable plane that stalled

#39

Post by dramm »

What a horrible click-bait title. There is nothing about a C185 or one modified with a STOL kit that is unstallable. A better title would be something like "Clueless pilot stalls aircraft. Which unfortunately is not an uncommon thing.

Re: The unstallable plane that stalled

#40

Post by lettergram »

roywiggins wrote: post #33
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…

Everyone ends up paying for that, in the form of insurance rates.

They could just not cover injuries where a seatbelt isn’t warn.

That said, we have evidence that seatbelt wearing didn’t impact insurance rates. Literally look at the rates over time, even after these laws were enacting, insurance rates rose fast as ever

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