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Coconut84
15th May 2014, 07:48
Hi Everybody, I've looked in CAR & CAAP and I've established the fact that CASA does not have any published minimas for stall recovery. Although the CAAP does touch on Aerobatic manoeuvres to be recovered above 3000', a basic stall isn't considered an aerobatic manoeuvre. Can anybody help me out in answering; why every flying college in Australia have adopted this arbitrary 3000' figure in which to recover from a stall. Is it written in something somewhere?:ugh:

Ex FSO GRIFFO
15th May 2014, 09:26
'It is written'.....

'Bold' pilot who try stall without sufficient altitude to safely recover....
Maybe Not live to grow 'old'......

It may well be an 'arbitary' figure, but then so may 2,000ft, or 2,500ft. or whatever.
This figure has been around for a loooong time - and I have forgotten any 'legal reference'.....:rolleyes:

Others will no doubt supply words of greater wisdom...:hmm:

I had student in the 'old days' who objected to the time consuming climb back up to 3,000ft following manoeuvres which involved some height loss.
I wonder where he is now...??:eek:

allthecoolnamesarego
15th May 2014, 09:32
Check the definition of 'aerobatic'. From memory it references a min speed (1.3vs??). Therefore, I think that means a 3000' minimum.

27/09
15th May 2014, 09:53
Check the definition of 'aerobatic'. From memory it references a min speed (1.3vs??).

Really, must be an Aussie definition. I fly briefly every day at 1.3 Vs in a non aerobatic aircraft. :E

TOUCH-AND-GO
15th May 2014, 09:57
A 'basic' stall may not be considered as an aerobatic manoeuvre. But a stall may impend into a wing drop or an incipient spin. There for a sufficient height of 3000' is used as a safety precaution. :ok:

Well that's my understanding...:}

Avgas172
15th May 2014, 09:59
I have often wondered why some think that climbing to a given altitude is a waste of time, in my book it is still aviation and demands arguably more skill than cruising at a set altitude for hours on end to get to a point from which you shall return from whence you came ....

Ixixly
15th May 2014, 10:15
I think this sort of thing comes up because of peoples conceived notion of what an "Aerobatic" is, everyone thinks of it as a manoeuvre specifically used in an "Air Show", but CAR 1988 (Correct me if I'm wrong) defines it as:
"… manoeuvres intentionally performed by an aircraft involving an abrupt change in its altitude, an abnormal attitude, or an abnormal variation in speed."
Now a stall is a manoeuvre that is performed intentionally and (usually) involves and abrupt change in attitude and/or possibly altitude, therefore it could certainly be classified as an "Aerobatic manoeuvre" therefore requiring the 3000ft.

But honestly that's only if you're splitting hairs and looking for a way to really try to justify the 3000ft recovering altitude, me personally I just think it's a good idea and don't see why not unless you're really worried about the extra few minutes to get to 3000ft in which case stop being so damned stingy!

I guess really everyone once upon a time thought "Well, if 3000ft is good enough for aerobatics it should be good enough for stalls then, let's go with that!" and so it became an un-written rule :D

airwolf117
15th May 2014, 10:54
At my old flying school it was 3000ft solo and 1500ft dual.

While it might not be a law, its just an accepted common practice for safety.

djpil
15th May 2014, 10:58
Reg 155 has this statement:

(2) For the purposes of subregulation (1), straight and steady stalls or turns in which the angle of bank does not exceed 60 degrees shall be deemed not to be acrobatic flight.
So, my opinion is therefore that such stalls do not need to be performed only in day VFR in an aerobatic aeroplane.
I don't see a reason to have subregulation (2) at all unless somewhere there is a rule stating that such stalls are aerobatics - perhaps there was and it no longer exists or there is and many of us don't understand it (Ixixly explains).

Subregulation (2) excludes sub (1) but not sub (3) indicating that subregulation (3) applies to those stalls i.e. a minimum height of 3,000 ft.

Hopefully clarified with the CASRs coming in the fullness of time.

Sunfish
15th May 2014, 11:20
My demonstration when a student of a deliberate spin and recovery was in an aerobat. Stalls straight and level in anything else at 3000'' just in case of a messed up wing drop recovery and resulting spin - which has happened to a mate of mine.

fujii
15th May 2014, 11:30
A three poing landing in a tail dragger is also called a full stall landing. Landing is not an aerobatic manoeuvre although try to make it so.

5-in-50
15th May 2014, 11:58
There is NO CASA rule regarding the minimum altitude for stalling.

The only rule you'll find, will be in your company / club Ops Manual, if they state a standard that must be adopted by it's pilots / members.

These arbitary figures are handed down over generations and never questioned.

Here's another one:

It s**ts me to no end when a student is taught to conduct a 360 degree clearing turn at 30 degrees AoB, before then practicing a 45 degree AoB steep turn. As if conducting a 45 degrees AoB turn is somehow less safe and requires an entire orbit at slightly less AoB to mitigate risk.

A simple airspace clear procedure of looking out all around is sufficient, but people will just do what they were taught without thinking why.

And one more for good measure:

HASELL checks before steep turns. The Day VFR syllabus specifies that you should perform an 'airspace cleared' procedure before steep turns, not HASELL. But people do that one also, because that's what Instructors hand down between generations.

BlatantLiar
15th May 2014, 12:40
I do my stalls at 1ft when I'm landing in most aircraft. Hopefully I'm not breaking the law by doing an aerobatic manoeuvre below 1500 in my case. Do stalls at whatever height is within your own perceived limitations and dont let anyone else tell you otherwise.

Dangly Bits
15th May 2014, 13:26
There are only 2 heights to stall an Aeroplane from. 3500 feet or 3.5 feet!

sheppey
15th May 2014, 14:33
(quote) I guess really everyone once upon a time thought "Well, if 3000ft is good enough for aerobatics it should be good enough for stalls then, let's go with that!" and so it became an un-written rule (/quote)

That's probably close to the truth of the matter.

Keep in mind that climbing to above 3000 ft in order to recover by 3000 ft is a good money spinner for both the flying instructor and the flying school. Especially on a hot summer's day when the rate of climb is low. Even the RAA "require" stalling in a ultra light like a Jabiru be conducted to recover by 3000 ft. That is blatant stealing money from the student especially as LSA types not only hardly stall they just waffle and recover in less than 50 feet. Again a nice money spinner.

CASA rightly state that a stall is not an aerobatic manoeuvre. Interestingly, some gliders have a wing drop at the stall yet it is quite normal for glider pilots to carry out a stall and recovery at 1000 ft and they don't even have a prop slipstream to aid recovery.

The recovery by 3000 ft should be dependant on aircraft type. For example, it would be most unwise even for an experienced pilot to conduct a powered landing configuration stall and recovery in a DC3 under 5000 ft. This because of the strong possibility of a vicious wing drop on that type. . Remember certification standards of those wartime types were less stringent than now. It can lead to an incipient spin in a DC3. Been there-done that on countless occasions as an instructor on the type.

Someone mentioned one operator had a company rule saying stall recovery to be made by 3000 ft if solo but 1500 ft if dual. Presumably talking about Cessna and similar types. Well, assuming the solo student has been signed and certified as competent to recover from stalls before first solo, if he wasn't competent to recover from stalls within stated height loss, then the instructor would not have sent him on his first solo. But to split the height between 3000 ft solo and 1500 ft dual is illogical. Either the student is competent or he isn't.

The long held 3000 ft stalling minimum practice height has been a flying school/instructor con for decades. But it makes money and that is the main reason why flying schools and their instructors still trot out varying reasons for its retention. Isn't it quite a coincidence that it is also the minimum height for aerobatics recovery?

Sunfish
15th May 2014, 20:21
Sheppy, I don't believe the 3000 ft. height recommendation is just a money spinner, it is there to provide a buffer for serious mishandling of a recovery resulting in a spin.

I am aware of Two events that resulted in spins, one inverted, caused by mishandling during endorsements where the aircraft lost a lot more than 1000 ft.

I am also aware of an endorsement in a Sportstar that went slightly pear shaped. It started with the instructor saying: " This little aircraft won't really stall, it just mushes down, watch this......." which turned out to be reasoably exciting, for when a dropped wing was picked up, it immediately dropped the other one, and so on.......and we weren't at 3000 ft either!

Sop_Monkey
15th May 2014, 23:01
Not sure where the 1.3 vs comes in here. You could only have 20 knots on the ASI and not stall if the wings are unloaded in a negative g maneuver.

43Inches
15th May 2014, 23:05
Sheppy, I don't believe the 3000 ft. height recommendation is just a money spinner, it is there to provide a buffer for serious mishandling of a recovery resulting in a spin.

I am aware of Two events that resulted in spins, one inverted, caused by mishandling during endorsements where the aircraft lost a lot more than 1000 ft.

I know of one 152 student lock up where the aircraft lost 2500ft before the instructor knocked out the student. I've seen 152s and PA28s lose over 1000ft in stalls where the student mishandles the situation. The closer to the ground you are the more likely a student will freeze on the controls when they notice the ground rushing up at them. If you havn't seen this then you do not have a lot of time instructing or you are not really practising stalling.

Don't forget that the closer to the ground you are the more likely the stall may be affected by wind shear or turbulence leading to more likely event of an excursion.

The flying training orgs I've worked for have mostly been trying to cut the cost of training times to be competitive. The minimum 3000ft for stalling was always viewed as a safety margin. It also allows you to let the students stuff up and get to the point you have to recover and show them their error of technique.

If the stalling is conducted as part of basic training you should be revising procedures during the climbs and descent so as not to waste the time.

Howard Hughes
15th May 2014, 23:13
Recently completed a turbo prop sim re-currency in the US. Stalls are now done as 'scenario based', different configurations, distractions (head down doing paperwork, multiple ATC clearance changes, etc...), including one at 200 feet on approach. I found this type of stalling far more beneficial than anything I had done in an aircraft at 3000/5000 feet. :ok:

43Inches
15th May 2014, 23:27
Recently completed a turbo prop sim re-currency in the US. Stalls are now done as 'scenario based', different configurations, distractions (head down doing paperwork, multiple ATC clearance changes, etc...), including one at 200 feet on approach. I found this type of stalling far more beneficial than anything I had done in an aircraft at 3000/5000 feet.

This is what a simulator should be used for. Even the aircraft based stalling lesson should be based on possible scenarios after the basics are done. Especially around landing stuff ups where the nose is too high, high drag after a bounce or balloon, or results of tightening the turn to final at too low a speed. These are not things you would want to practice at low altitude in the real aircraft with low experience pilots. The whole point of these exercises is basically a warning to stay away from these scenarios as they can bite hard.

djpil
15th May 2014, 23:39
I agree, Sunfish and 43Inches, I have been with students attempting a straight stall and suddenly entering a spin with significant loss of height. Sunfish, my guess is that it was not an inverted spin - a "flick" entry into an upright spin will have the aeroplane on its back initially.

I thought the thread was about the regulatory issue, not what was safe and/or smart. VH-XXX seems to have pointed to CASA's view of the convoluted words in the current regs.

VH-XXX
16th May 2014, 00:00
VH-XXX seems to have pointed to CASA's view of the convoluted words in the current regs.

Actually DJP, I was just editing that post and deleted it by accident. I was incorrect, the VFG does not suggest 3,000 ft for stalls, but talks about Acrobatic flight. Where we always "land" on this issue, is that a stall can quickly become "acrobatic" flight and for acrobatic flight we must be at 3,000 ft (unless exempted) so therefore, you are in theory legally tempting fate by conducting stalls below 3,000 ft AGL.

Acrobatic Flight (CAR 155)
An aircraft:

For the purposes of the avove, straight and steady stalls or turns in which the angle of bank does not exceed 60 degrees shall be deemed NOT to be acrobatic flight.

Except with the permission in writing of CASA, a person shall not engage in actobatic flight in an aircraft:

- At a height lower than 3,000 ft above the higest point of terrain or any obstacle thereon, within a radius of 600m of a line extending vertically below the aircraft.

43Inches
16th May 2014, 00:14
I thought the thread was about the regulatory issue, not what was safe and/or smart. VH-XXX seems to have pointed to CASA's view of the convoluted words in the current regs.

The regs don't specify a minimum height for straight and level unaccelerated stalls, this is true. What is the motive behind this thread though, to mandate they impose a minimum, or a student trying to save a few bucks and argue with their instructor, or are there instructors out there scaring students at low level and the students are asking for advice on the actual rules.

Imposing a minimum is type specific, so one altitude can't be deemed safe for all. Recover by 3000ft is a good starting point as you have lots of room if it gets worse than anticipated. You also run into problems if you mandate no stalls below 3000ft and your aircraft requires it to land. I will add a well trained competent pilot can stall and recover with very little height loss safely without much chance of an adventure in an aircraft he is familiar with. In the case with most flying schools/colleges in Australia the normal situation is unfamiliar/inexperienced pilots being taught how to fly, operating close to the stall with these students can result in very rapid loss of control.

Saving cash during training is more about smart planning and study than 10 minutes climbing on one or two lessons.

I have heard of instructors performing manuevres such as stalls at low level and almost coming to grief, scaring the student and the student reporting it. Its not worth it from an instructors point of view, whilst you are on board and even to a point whilst the student is solo you are responsible.

djpil
16th May 2014, 01:05
VH-XXX, you should've provided the full extract from the VFG as that bit about stalls not being aerobatics "for the purposes of the above" I guess means what it says i.e. for the purposes of the above only. i.e. you can do stalls IFR, at night and you can do them in a normal category aeroplane.

Under the heading of aerobatics per CAR 155 it specifically mentions straight stalls with that specific exemption for the requirements above. It then goes on to state that 3,000 ft is the minimum height.

It still seems to me that CASA's rule is 3,000 min height for straight stalls.

VH-XXX
16th May 2014, 01:14
Easy for you to say, it won't let me copy and paste from the VFG it would seem :ok:

Wally Mk2
16th May 2014, 01:29
I believe the 3000ft thingy is just an accepted std in the industry to cover all sorts of miss-events such as to keep the A/C a min of 1000ft which covers the low flying over populous area etc as just an Eg.


Wmk2

jas24zzk
16th May 2014, 13:02
I agree with Wally.

I also see no point in challenging the accepted standard. Many reasons have been posted here as to why this TRAINING EXERCISE could or could not be conducted at a lower altitude....for eg a DC3 needs more room...

Keep it into context..the original Q was posed for ab-initio.

I'm glider initial trained. I like many others from that genre did my spin training, not above 12-1300 agl. Theoretically I am comfortable with it.

Consider power instructors, their spin experience, is most likely limited to what they did during their rating.....99% of GFPT/PPL holders have never done a fully developed spin. Glider pilots spin every type they fly, and practice until the reaction is automatic, even in a look away situation.

I'm comfortable in spinning and stalling, but given the choice, i'll have the 3k AGL option thanks.

Student learning + Instructor that might not be comfortable...all the room we can get regardless of the dollars

Centaurus
16th May 2014, 13:30
I understand that NZ Regulations require 1500 ft agl as the minimum altitude for training in stall recovery. At least that is a realistic safe figure instead of the arbitrary figure used in Australian flying schools of recover by 3000 ft. I suppose its nice to be cautious just in case a student happens to stuff up on the recovery but where do you stop? Why not 5000 ft just in case a student really stuffs up. Better still why not wear a back pack parachute for stalling if it is that dangerous...

Sop_Monkey
17th May 2014, 08:46
Very good points on the stall training with different scenarios.

Even now, very experienced pilots are still getting caught out with departure from controlled flight. Some airshow pilots, among them.

I like to look at it this way.

Low altitude: speed is your friend.

Low speed/stalling: height is your friend and plenty of it.

Money in the bank.

scroogee
17th May 2014, 09:10
Nothing in the NZ rules about minimum altitudes for stalling or recovery. We used 2500' for most exercises where I was.

I had one pre-solo student put me into a RH spin onset at at 2500' (C152, full aft column, full power and a badly rebuilt wing) and another pre-cpl while doing wing-drop (full flap, with power) at 3000' (admittedly no real horizon for that one).

john_tullamarine
17th May 2014, 10:39
C152, full aft column, full power

.. why would you be doing that sort of thing ?

43Inches
17th May 2014, 11:14
C152, full aft column, full power

.. why would you be doing that sort of thing ?

Especially with;

a badly rebuilt wing

The point is helping them avoid and if needed recover from a stall in the approach config, not scare them or assist their progression into the afterlife.

Centaurus
17th May 2014, 12:18
and another pre-cpl while doing wing-drop (full flap, with power) at 3000' (admittedly no real horizon for that one).

Of course you would have written up that defect in the maintenance or equivalent document:E

Did you "arrange" the wing-drop by a cunning push on a rudder pedal at the point of stall? :E Or did the wing really seriously drop with full flap and power on. For certification requirements, the maximum wing drop permitted during the stall is (I seem to recall) 15 degrees. Any more than that, the aircraft is considered as un-airworthy and should be grounded until the defect is fixed. Usually it is a rigging problem.

Too many instructors/pilots are happy to accept un-airworthy aircraft because they fear writing up a defect will jeopardise their employment. Or they are too casual about reporting defect. It is not enough to verbally tell someone there is a purported defect - there is a legal requirement to record it in writing on the approved maintenance document. It is fact of life that not all aircraft owners are understanding; especially when it comes to paying for additional maintenance beyond the standard schedule

djpil
17th May 2014, 12:46
The certification requirement is not applicable when the student makes incorrect or nil control movements.

Biggles78
17th May 2014, 13:15
A CAA Testing Officer with the initials NK based in NZCH would often have a CPL testee do a fully developed stall over the Eyrewell low flying area at 1,000' AMSL. I had an instructor stalling the aircraft on final during my CPL training. Didn't much like it but it was a good learning experience. Things look a lot different down from 3,000'.

The Aero Club President took the aerobatic aircraft (never liked the thought of having to bolt 40lbs of weight to the tail to make it spin) out one day and for some unknown reason he decided that 5,000' was where he wanted to start. He said he usually started spinning at 3,000' but not that day and as luck or fate would have it, the Beagle went into a flat spin. He said if he had started at his usual 3,000' he would not have recovered in time and be recounting the story.

As for the 3,000' being a "fund raiser" for the flying school; I often used the clime to practise climbing turns, compass turns or wear the hood and log I/F time. Not a waste at all IMO.

43Inches
17th May 2014, 13:35
I had an instructor stalling the aircraft on final during my CPL training. Didn't much like it but it was a good learning experience. Things look a lot different down from 3,000'.

I have heard of an instructor who did this down to around 50 or 100ft in PA28s, used to demonstrate it as a way to lose height, can be done and has been done. What is the problem is inexperienced pilots with much less ability see this and copy it. The blokes who show off these manuevres have experience and some knowledge of when and when not to do it, they don't usually pass that part on after the demo. The students who witness the event then have a go and usually stuff it up. Instructors need to be leaders and keep things simple and to the point, even doing something and then saying "I'm experienced and can do that". leads a student to thinking maybe 10 hours I can do that on my 2nd solo etc... Do you specify how much experience is enough to bust a limit? Even on a simple navex diverting cautiously rather than pushing on may save the life of your student in the future, showing them how you pushed on and upgraded to IFR doesn't help.

scroogee
17th May 2014, 21:36
"C152, full aft column, full power

.. why would you be doing that sort of thing ?"

"Quote:
C152, full aft column, full power

.. why would you be doing that sort of thing ? Especially with;


Quote:
a badly rebuilt wing
The point is helping them avoid and if needed recover from a stall in the approach config, not scare them or assist their progression into the afterlife."

Arghhhh.

It wasn't taught or deliberate, I included it as an example of how a student could mis-handle the exercise and how other factors could come into play. We still would have had spin entry with the column and power situation, just the badly rebuilt wing made the aircraft go right rather than left so the conditioned rudder didn't help.

Because of the wing the aircraft was actually good later for more advanced students as it meant they actually had to pay attention rather than resond by rote.

And you're right, it took a while for that student to regain some confidence.

Oktas8
18th May 2014, 04:04
Just a note- a couple of posters have mentioned NZ rules.

Whilst no reputable country legislates for min. height for stalling, the NZ Flt Instructor Guide (http://www.caa.govt.nz/FIG/instructions.html) does recommend a minimum height of 2500'. A flying school minimum of 1500', dual only, is not uncommon.

When I was conducting renewals a few years ago, Mr CAA (JP) told me that failing to conform with the FIG without a well considered reason would be grounds for failure. So it was, sort of, a rule.

I had one pre-solo student put me into a RH spin onset at at 2500' (C152, full aft column, full power and a badly rebuilt wing)

Dear oh dear, on so many levels! Now I remember why I gave up flight examining and became a humble FO.

Don_Apron
18th May 2014, 10:50
On the subject of prestall sink at low altitude I used to watch in awe as Fletcher topdressing/AG aircraft pilots used this to great effect. The a/c not only looked like a brick, with barn doors attached but they dropped like bricks also, when this loss of lift technic was implemented. Fascinating to watch. However these guys were doing it day in and day out and knew what they were doing. Like a lot of maneuvers unless you're doing it as a day job great care must be taken with the added precautions! I would include FTO's/Examiner's even more so.