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The unstallable plane that stalled

fearoflanding.com

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Re: The unstallable plane that stalled

#151

Post by eesmith »

andrewaylett wrote: post #89
eesmith wrote: post #37

Earlier quoted context omitted.

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 use…

Seems like it's maybe a UK thing, and my (fairly limited) water-sports experience is kayaking and small sailboats. Isn't the English language fun?

Interesting! I checked out what the RNLI had to say at https://rnli.org/safety/lifejackets and that page only mentions lifejackets along with gas.

However, if you "Download our lifejackets and buoyancy aids guide as a PDF (3.48MB)" at https://rnli.org/-/media/rnli/downloads/1983319_choose_it_we... you'll read "Children’s lifejackets may rely on foam, air and foam, or CO2 only to provide buoyancy" and "Air and foam or CO2 lifejackets meet the requirements of a level 150 lifejacket and are suitable for offshore use. Normally, foam lifejackets provide level 100 buoyancy and are suitable for inshore use."

A further search of the RNLI site finds https://rnli.org/magazine/magazine-featured-list/2018/june/t... with "The foam-based Beaufort lifejacket [of the 1970s] upped the buoyancy level, allowing a crew member to also support the person being rescued." but by the 1990s "The bulkier gear of all-weather lifeboat crews meant they needed a more compact lifejacket, which inflated automatically on hitting the water using a built-in gas canister."

Since I learned my small watercraft skills in the warm waters of Florida, instead of chilly UK, I can see how that would make a difference.

Re: The unstallable plane that stalled

#152

Post by rob74 »

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'm not a pilot or an aviation expert, but I think you're arguing against a strawman here. The investigation report said nothing about determining the precise stall speed, it just recommended "that pilots be informed about the stall behaviour of the Robertson short take-off and landing kit on the Cessna 185 aircraft, both by listing the issue in the aircraft flight manual supplement and through education through the aviation authority". The fact that the stall speeds were not listed on the test flight report was just further proof that the pilot didn't actually test the stall behaviour of the aircraft.

What the investigation report also didn't mention is that pilots should actually practice stall recovery and not just think "if I believe strongly enough that my plane is unstallable, I can ignore stall recovery". But that probably goes without saying...

Re: The unstallable plane that stalled

#153

Post by datascienced »

JumpCrisscross wrote: post #147
WalterBright wrote: post #68

Earlier quoted context omitted.

> nobody should be flying an airplane like this so close to the edge the exact stall speed needs to be known numerically within one knot. An experienced pilot can feel the stall coming on with a bit of a "burble" in the stick. My dad (fighter pilot) told me that knowing exactly where the stall point is is life and death. When you're in a dogfight, the winner often is the one that can turn inside the other. Turning as…

> An experienced pilot can feel the stall coming on with a bit of a "burble" in the stick Stall recovery has also been an essential part of my flight training.

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

Re: The unstallable plane that stalled

#154

Post by wkat4242 »

JumpCrisscross wrote: post #147
WalterBright wrote: post #68

Earlier quoted context omitted.

> nobody should be flying an airplane like this so close to the edge the exact stall speed needs to be known numerically within one knot. An experienced pilot can feel the stall coming on with a bit of a "burble" in the stick. My dad (fighter pilot) told me that knowing exactly where the stall point is is life and death. When you're in a dogfight, the winner often is the one that can turn inside the other. Turning as…

> An experienced pilot can feel the stall coming on with a bit of a "burble" in the stick Stall recovery has also been an essential part of my flight training.

The most dangerous situations are when you're flying low and slow like before a landing though, when there's often no time for recovery (especially when you end up in a spin due to asymmetric stall). When I was flying I always worried about this too the point of approaching too fast. But I never finished my PPL anyway

Re: The unstallable plane that stalled

#155

Post by wkat4242 »

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…

Yeah and because of that we're also still exposed to lead fumes and pollution :(

It's really time for GA to get into this century.

Re: The unstallable plane that stalled

#156

Post by wkat4242 »

aaronharnly wrote: post #131
teeray wrote: post #126

Earlier quoted context omitted.

My favorite anecdote I heard of from a flight instructor is that of a cargo plane taking off that had some heavy vehicle tied down in its hold. It broke free of its straps during takeoff and rolled to the back of the aircraft, which shifted the CG such that the plane entered an unrecoverable stall and crashed.

I’m not sure if this is the one your instructor was referencing, but there was a fairly notorious such event in Afghanistan about a decade ago. https://en.wikipedia.org/wiki/National_Airlines_Flight_102 https://www.faa.gov/lessons_learned/transport_airplane/accid...

Also the excellent (as usual) write up from Admiral Cloudberg https://admiralcloudberg.medium.com/strength-in-numbers-the-...

Re: The unstallable plane that stalled

#157

Post by tim333 »

buildsjets wrote: post #94

I've been involved in general aviation since the late 1970s, currently commercial/twin/instrument rated, have a degree in aerospace engineering, and do what my username says for a living. So I know airplanes, and why they do the things they do. But an appreciation for what is physically occurring during a stall, how the resulting balance of forces influence the aircraft handling during a stall and recovery, and why t…

Yeah I got a PPL and there was no mention in my training of stuff like that which happened to this plane. That said I'm surprised it behaved like that - turning dramatically to one side on stalling. All planes I've flown, model aircraft that I've built and paper darts just lose lift when they stall rather than yawing to one side. It seems there was something off with the aerodynamics of that plane.

Re: The unstallable plane that stalled

#158

Post by ExoticPearTree »

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.

> Stall speed is an approximation. It's baffling that GA aircraft don't have one of the most safety-critical measurements: AOA.

All aircraft equipped with a six pack, you have an artificial horizon indicator which can tell you what is your angle of attack. And Cessna's have them in all planes, even 50-60 years old ones.

Re: The unstallable plane that stalled

#159

Post by speedbird »

buildsjets wrote: post #94

I've been involved in general aviation since the late 1970s, currently commercial/twin/instrument rated, have a degree in aerospace engineering, and do what my username says for a living. So I know airplanes, and why they do the things they do. But an appreciation for what is physically occurring during a stall, how the resulting balance of forces influence the aircraft handling during a stall and recovery, and why t…

I’ve got a few hundred hours in the usual pipers and light twin, but I’d say I never really learned about flying, and particularly “flying the wing” until I got into aerobatics and deliberately upsetting the aircraft. It’s priceless learning to go beyond the normal and being comfortable with it.

Re: The unstallable plane that stalled

#160

Post by speedbird »

tim333 wrote: post #157
buildsjets wrote: post #94

I've been involved in general aviation since the late 1970s, currently commercial/twin/instrument rated, have a degree in aerospace engineering, and do what my username says for a living. So I know airplanes, and why they do the things they do. But an appreciation for what is physically occurring during a stall, how the resulting balance of forces influence the aircraft handling during a stall and recovery, and why t…

Yeah I got a PPL and there was no mention in my training of stuff like that which happened to this plane. That said I'm surprised it behaved like that - turning dramatically to one side on stalling. All planes I've flown, model aircraft that I've built and paper darts just lose lift when they stall rather than yawing to one side. It seems there was something off with the aerodynamics of that plane.

STOL kit and possibly trim setting causes tip stall rather than root.
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