I once stalled a K13 glider at 80knots with about 80deg bank, it took a lot of pull!I've also final turned a C152 at 60deg at 60knots (descending). So all this crap about bank angles wouldn't apply unless you are trying to keep it level without added throttle/speed. Shirley?

Stall warner calibration is a problem with many light aircraft. Fly the attitude please, with a check of the asi from time to time. Learn to feel the aircraft, know how it handles.

And any passenger wanting to take control when I am P1, flying my own aircraft, had better be prepared to learn to fly without arms.

Shirley replies:

This bank angle stuff does apply because as you just pointed out, your stall speed does increase, even if you are in a dive. The majority of pilots are so uncurrent/unconfident in generic 3000ft straight and level stalls, let alone an accelerated version in landing configuration at a high angle of bank at low level. There is a fatal difference.

Yeah, well obviously! That's because stalling has eff all to do with speed, and everything to do with angle of attack.

I've stalled a Yak at 140 kts, and flown it at zero airspeed with no stall. I do wish all this pish about 'stall speed' would go away! Of course we'd need AoA indicators, and I wonder why they are not standard fit, since flying is all about the wing, and the wing is all about AoA.

My standard dead side descent in the Chippy was done near-wings-vertical, but wings unloaded. Which was also my method of 'throwing away' an aerobatic manouvre where I'd commenced the pull-up and wanted to exit back to level flight quickly and without drama.

Crikey, puff your chest back in! Just a jocular response to your 'rip your arm off' comment, I would be quite happy to die with you Bose.

By the way, just got back from Sainsburys and they have half price Heidsiek champagne on offer if anyone is looking to uncork one the morrow. Just opened a bottle and it's quite quaffable.

No, all of this crap about bank angles doesn't apply unless you are in a level turn. Or not loading the wings. Or the various other permutations we've been discussing.

So if you were flying with me ( I think you are far more experienced than me if I remember some of your previous posts) and I was P1, the aircraft commander and you were just along for the ride, no matter what I did you wouldn't take over? Even if you called 'Airspeed' if I was low and slow or some other life threatening situation?

No, all of this crap about bank angles doesn't apply unless you are in a level turn. Or not loading the wings. Or the various other permutations we've been discussing.


I thought that's what I said. The glider was certainly loaded, the C152 was not.

Yes you did say that, I was just agreeing!

Jeez, I give up. On a more serious note, I wonder how many commercial crashes with the loss of many thousands of lives over the years could have been avoided without this attitude. Not having a pop at you in particular but I'm surprised at the more experienced pilots here giving the 'I have a squillion hours therefore how can you ever be more right than me with your 250' line. I thought those days were over.

The number of freshly licensed PPLs who think you can't turn at a bank angle over 15 degrees on base to final is amazing...and a reflection on flight training I am afraid.

To the OP, I've known stall warners to be conservatively off by up to 10 knots, get the pilot to demonstrate an actual stall at height and compare the airspeed then to airspeed at the warning, he might just know something you don't

He could also of course be an idiot, but at least this way you'll know.

Lone Ranger, please read my post above. Stalling is not directly related to airspeed. Because of that, such an IAS indication is meaningless. Wing loading will affect the indicated stall speed, so pilot and pax weight come into it, and fuel weight. And of course if you're in a balanced turn (so G loading becomes a factor) you can forget the IAS / stall relationship.

AoA is ALL the wing knows about as far as stalling is concerned. It never varies for a given configuration (flaps etc), regardless of loading.

So how do you fly a bad weather/low level circuit?

Shaggy, read your post./...it does nothing to increase my understanding.
A wing stalls at a certain AoA of course, but it also is most certainly 'related' to airspeed
You seem to be forgetting how a stall warning vane actually works

Reference passengers interfering with controls, in the event of an accident and injury etc the pilot may be able to take a civil action against the passenger who interfered by proving that such action precipitated the accident.

Crikey! Even when I was a PPL stude back in 1978 circuits at Barton were 800' QFE. So by final turn one was down to maybe 500' max (I'd done the rote power, flaps, trim thing on base, and did it again on final).

Once I started to learn to fly into strips etc, height on final turn could be as low as you can go before the wingtip is in danger of hitting the ground!

Now obviously you won't be doing 20 foot final turns as a stude or a low hours PPL... but 800 feet? That's just silly in a little aeroplane (unless there's some local noise rule).

There's a relationship between IAS and stall, but it's not in any way reliable for the reason I give (re-read the post). 0 or 140 knots, the stall being at 140! How inconsistent is that? Yes, that was in aeros, so an extreme example.. but it demonstrates the point and the wing has no idea whether it's doing aeros or just circuits.

How do you think a stall warning device works?

No, I haven't forgotten, but your post makes me wonder if you ever knew how it works? If you think it's triggered by IAS, for your own safety go read 'Stick & Rudder' before you become a statistic!

Whether it's a vane or a 'whistle' type of warner, it's triggered by AoA!

The 800 ft sounds more like a misunderstanding to me.

Quite often a student will say "Instructor Bloggs said this or told me to do this".

And then when you research and ask Instructor Bloggs nothing of the sort was said or something was said which was misunderstood.

This is why as instructors we are in the "communication business" - be precise and make sure what you teach isn't misleading.

I'd like to thank all the posters here for pointing out how close to death I have been when flying aircraft without stall warning equipment fitted. What were Geoffrey DeHavilland and others thinking?

Flying a 3-axis microlight with no stall warner installed (cheese us! that would add another 600 grammes or so!) I can only agree. Turned a handful of circuits yesterday, trying various approach speeds and feeling the plane, I am coming to terms with it. Even the one time I let the ASI get rather low I felt it in my pants (or was it my stomach? can't be sure) before confirming on the needle.

Don't you get pre-stall buffet? That was the warning on the Chippy (thank you Mr de Havilland)! And of course it's entirely AoA related (as is every stall warner I've ever met)!

Back to the taking control thing.

A real world story of getting it right.

I was right hand seat, instructor, sat back arms folded but monitoring a very good student on his tailwheel (and an antique type) conversion. At 400ft just after take-off, we had a sudden loss of power. My student, not unreasonably said loudly and clearly "you have control Genghis".


I took control, called a Pan, and was manoeuvring to land back (eventually) on a disused crosswind runway. Partway through the manoeuvring - turning, stressed, trying to relate attitude to variably sloping hills around the airfield, and close to the ground, my student recalls noting that I was very close to the stall. His recollection is that he said something like "Genghis, check your airspeed".

I do not recall hearing that. I do recall at that point, glancing at the airspeed, realising from that and stick pressure and pitch attitude that I was close to the stall, and easing the nose forwards. Almost certainly I was responding to what he said, but too stressed to be consciously aware that that was what I was doing.

His clear verbal reminder to me almost certainly saved 2 lives and the aircraft.


I agree that a passenger should not be taking control from a qualified PiC under almost any circumstances. (Obvious circumstances when he might include PiC having a heart attack, or inviting pax to take control to have a go). However, it is excellent airmanship to clearly draw a safety concern to the attention of the pilot. The pilot then, who hopefully knows their aeroplane well enough to form sensible judgments, can do the right thing. In *some* aeroplanes that *might* be to continue to fly with the stall warner operating.

G

SSD, I was being sarcastic. People are obsessed with the stall warning and not flying the aircraft.

Guess what I am doing next weekend!! Circuits with no instruments! Cant go solo with no SPL (still waiting on CASA), so I am using the opportunity to fine tune my circuits since I still have someone sitting next to me. I asked the FI last lesson if we could go up and fly without any instruments, so I could try learn to see and feel airspeed and altitude with out looking at instruments.

I was taught to make the turn onto final at about 600feet. Also taught 65knot final with full flap (C172S), obviously dependant on conditions.. Oddly enough, if you drop much below 60knots in the c172, the tail feels like its sinking and plane pitches up.

FWIW, when I first started training, they tell you to set certain RPM and on downwind, base and final. Likewise, the tell you what airspeeds to achieve. I have since learned that these are only guidelines, and whist they are ideal, sometimes you need a bit more or less depending on conditions.

Anyway, sorry about the hijack. Learning lots from you guys and gals!

To turn your argument on it's head, if I were flying in the RH seat with you and you pranged the a/c even after I had warned you about low airspeed/ insert frightening situation of choice, and I didn't take control and sat through the inevitable crash, would I have a claim against you? I would have an insurance claim obviously but if I pressed for damages in that I could have prevented the accident had you listened would that stand up in a court of law? We're not talking about pax here we're talking about qualified and current pilots. Would the court say 'Well as a current on type and qualified pilot Mr Wilson why didn't you take control?'

Sorry Fujii... So was I! I agree with you entirely! :ok:

Dave Wilson, I am not a lawyer!

One relevant point that has been missed is that when pilots are task saturated the very first sense the brain deletes is hearing. Your ear hears but the brain says "hey we're busy enough here - we don't need that stuff!".

So it's possible the pilot is not aware that the stall warner is operating (how many have landed gear up with the warning horn blasting away?).

Similarly the pilot may not be aware of your airspeed prompt. You might have to break the pilot's pattern by (for example) shaking him on the shoulder etc.

In the event of an accident with injury etc IF the passenger(s) can prove negligence on the part of the pilot they would have a case for civil action. But being negligent implies a deliberate act rather than a "genuine" mistake as I understand it but, as I say, I am not a lawyer.

But this is really getting highly hypothetical now. Sounds as though the OP was flying with someone who was not that competent.

One question I often ask students/pilots is "Can I stall if I am diving vertically towards the ground?" (with model a/c in hand pointing vertically down!) The answers are quite illuminating since almost exclusively all their stalling training has been done from more or less level flight and/or modest bank angles.

Dave Wilson, my answer to that is that there is only ever ONE Commander on an aircraft!

I agree - but would still emphasise that the qualified and competent PASSENGER should draw the pilot's attention to anything of concern.

G

Genghis the Engineer, I agree of course! I was alluding to the strict legal aspect.

Exactly. It's not a point that is really driven home and it's one of the most important things to understand in flying. I suppose time and the syllabus are against most instructors. I don't come entirely virginal to the theory of it, before my whole 250 hrs as a powered pilot I spent 20 odd years as a glider pilot and was an instructor in theory of flight at a military establishment for four years. I already had the background when I started powered so any gaps were I suppose unconsciously filled in by me.

Also you can demonstrate the fact that the a/c can stall at any attitude/airspeed much more easily if the a/c is aerobatic.

Fly a loop and as you become inverted show the student "nose high, low speed (below 1g Vs) - but NO stall" and then when more or less vertical pull to buffet and show "nose low, high speed, STALL"

Firefly, yes, that's where my example of a Yak zero airspeed with no stall and seconds later a stall at 140 knots (both in the same manouvre) came from.

But I wonder if the average non-flyer (i.e. a low hour stude) would gain anything from such a demo? I suspect not.

Experienced pilots, however, should know this stuff. It seems many don't.

A graphic illustration a few years ago was the spitfire at an airshow, which looped too low.....pancaked into the ground....IIRC pilot killed, not a lot left of the A/c.

Can I (the student) have a crack at answering that?

If you are diving vertically to the ground, and you pull up to quick, the AoA can be exceeded and you will stall?

In my head, I visualise it as this: diving vertically to the ground, relative airflow is also vertical. Pulling out of the dive quickly, relative airflow is still vertical, but you are becoming horizontal, therefore AoA may be exceeded?

As for turns, I guess the same logic applies.When turning, to keep the plane flying vertical you would have to pitch up? So a steep turn in a vertical dive could still result in a stall?

Your question poses and interesting point for me though. How much can you bank a plane without it turning, and how do you do it. Thoughts of aerobatics in head and how they do it. Clear gap in my knowledge here, time to go do some research. I am at work now, I really need to get a model for these moments, visualising it helps a lot.

Shaggy Sheep Driver, I take your point but it depends on the instructor and how it is taught.

In the "olden days" my dad had students doing loops before they went solo.

If you have enough speed / power as much as you like! A classic example of this is a knife edge pass flown during many displays. The aircraft is flown straight and level down the display line but with 90degrees of bank applied.

It's done using a load of aileron input to hold the bank balanced with a shed load of opposing rudder to hold the nose up along with power to balance the weight of the aircraft since the wings are not developing lift. Technically the fuselage will actually have a significant positive AOA and will be developing some lift but not much! You 'steer' the aircraft down the display line using pitch at that point but I run out of rudder beyond about 60-70 degrees even at 200mph so never personally tried it right over at 90 degs!

If you ever go on to fly an ex mil jet you'll be shown high speed stalling as part of the conversion syllabus which is a bit of an eye opener to say the least!

Regards

UA

For part of the FAA CPLs we did all manner of accelerated stalls etc....My best stall was upside down at the top of a loop and we ended up falling with style. It was quite surreal, I can still remember watching the car on the road that we'd been using as a reference line 5000' below as the harness straps were fluttering around my ears and we were weightless, with an aero's FI laughling like a hyena beside me....I was a bit overloaded then and forgot to close the throttle so we were accelerating downward and a remarkable rate of knots. After what seemed like an eternity (probably a couple of seconds) he said "my plane" and recovered from my numerous botched recoveries in which I stalled about 10 times ( felt like it anyway).

Regarding taking over - Depends. I have taken over in the past when the person I used to fly with (in a shared aeroplane of which I owned a share) was destined to break the aeroplane on landing after flaring at about 50 feet and just waiting for the inevitable. Now I'd certainly take over if we were about to die horribly and I knew I could save us - self preservation and all that.

800'....our circuit is 800'....

Mad Jock ........ Unreasonable !
 

Jock I think you are unreasonable being critical of people who are turning onto final at 800 ft while deploying flap with the aim to be full flap speed stable at 500ft as they roll the wings level...........it's what I do all the time at small airfields.










Aircraft type Boeing 737-800, typical threshold speed 145 KTS.


I think a C152 or PA28 being flown this way is likely to be in the hands of a budding child of the magenta line !

FLY THE AIRCRAFT you are flying NOT the aircraft you aspire to FLY !

Basics......I agree
 

It goes all the way back to your first flying lesson the first clue should be the controls getting less effective, then the aircraft attitude followed by the light buffet...... Without getting too far into the theory those are the clues that should be ringing alarm bells in the mind of a low time pilot long before the stall warner sounds.

To fail to teach that, and mitigate that with a whole lot of guff derived from videos of airliner flying is to sow the seeds of an accident be it a C152 Turing final at some small airfield of an A330 over the Atlantic.

Dave, I invite you to note the word Passenger in my previous post. Not co-pilot, not instructor. PASSENGER. Pilot in command flies. Passenger does not interfere.

The OP never did answer my original question about the nature of the stall warning - i.e. intermittent or blaring. Noting his location, I'm also reminded of the need for particular vigilance in NVFR flight in many parts of Australia. There are not always many visual cues and, indeed, the strip lighting can be basic to say the least. Before the thread got silly, Mad Jock correctly made the point that flying around with the stall waring blaring is bad form. To that I'd add that anything other than the gentle turn rates appropriate in instrument flying are not wise in the NVFR environment, especially in locations where you need to keep all your wits about you to avoid sensory and other traps.

A rider on some of the comments re stall warning devices concerns certified (VLA) vs LSA versions of the same aircraft. I'm amused to see that my certified aircraft boasts a stall warning vane, while its LSA stablemates assume that our recreational pilot colleagues can go hang (figuratively). I doubt they lose any sleep over the omission.

I know AnC its got the stink of commercial ops. I would be at 600ft and do the last 100ft with 5 degs of bank on in the works machine. Did have one idiot that announced that it was illegal to do less that a 5 mile final in a commercial airliner.
This was just after he announced he was back to OAT to help out in the sim for an open day. It took nearly 500 sectors to batter most of the rubbish out of him and sort his handling out. I am sure he was a whizz with automatics. Unfortunately the only thing we had automatic was the engine start the rest of it you were doing it yourself.


In the tommy I would be at 300-400 feet and if the donk went I would be able to glide the rest of the way.