Stalls and Spins

[APenNameAndThatA]

I did spins today in a Super Decathlon. It turns out that spins speed up after the first couple of turns and it gets a bit physically intense. Its very different to gracefully autorotating.

 

And what about that bit when you put in full opposite rudder and stick forward and nothing happens? You just keep spinning. 😆 A second or two later, the spin starts to slow, but nobody seems to mention that bit where nothing changes for a while. 

 

And full power (180 hp engine but only 23” manifold pressure at 6000 ft) stalls? I thought the plane would do some sort of snap flip into a vicious spin but not much happened. 

 

I kept the wings level, in a stall, with the rudder for a couple thousand feet. Indicated speeds about 60 kts, and 1500 fpm. 

 

Its no humble brag that I still find stalls frightening. Like if I just hold the stick back, everything is still a bit too overwhelming to work out if what I have ended up in is a spin or a spiral. The uncertainty and waiting for a wing to drop (which is a catastrophe and must be avoided at all costs, right?) and what mysterious thing might happen next is what is anxiety-provoking as far as I can tell. 

 

Also, before I did this, I spent 2.5 months, going on about 90 rides at Movie World and Dream World so I would be game to do the stuff to make me game to stall. That was a while ago now.  

 

On reflection, now I know you can put in down elevator as soon as you put in opposite rudder in a spin, maybe you can do that in stalls. But my instructor said that if you put in forward elevator when you are inverted in the autorotation you might stay inverted. 

 

The autorotation stage is a mystery to me. And my instructor literally does not know when the stall ends and the autorotation starts. 🤷‍♂️  I brought that question up here before and no one else seemed to either.  

[facthunter]

You're not really going to know what's happening till you do quite a few more.   The Decathlon probably has Frise ailerons and you can't use out of spin aileron to hasten the spin entry if it does. IF you're scared it's not much fun. It should enter the spin in about 1/2 turn and very nose down. when it settles There's a big difference from some planes to others and you should know what's specific to the type. You are not supposed to be test pilots. In a spin the speed indicated stays a bit above the stall and there's little extra G load while in the spin.  If it's in a spiral the speed will build up and you have to prevent that getting away without  delay, or the plane may become over stressed. Nev

Edited December 16, 2021 by facthunter

[APenNameAndThatA]

5 hours ago, facthunter said:

You're not really going to know what's happening till you do quite a few more.   The Decathlon probably has Frise ailerons and you can't use out of spin aileron to hasten the spin entry if it does. IF you're scared it's not much fun. It should enter the spin in about 1/2 turn and very nose down. when it settles There's a big difference from some planes to others and you should know what's specific to the type. You are not supposed to be test pilots. In a spin the speed indicated stays a bit above the stall and there's little extra G load while in the spin.  If it's in a spiral the speed will build up and you have to prevent that getting away without  delay, or the plane may become over stressed. Nev

I was wondering how come I was keeping the ailerons neutral while entering the spin. 

[Student Pilot]

I don't think there is any need for much more than a couple of spins in training. A lot more should be done on slow flight and slow manoeuvring so you know the aircraft and how to avoid stall/spin.

[facthunter]

Well, too many "pilots" do none. My comment was don't expect to get the full picture regarding spins   with just a little exposure. Avoiding is what will save your life as at a low height you won't be able to recover from a spin or decent spiral  or even an extreme pitch  down attitude.

  Any slow flight has added risks. You reduce your margins and are more gust affected..

  The general stalls  training is inadequate and even likely to cause erroneous responses. Nev

[Student Pilot]

1 hour ago, facthunter said:

Any slow flight has added risks. You reduce your margins and are more gust affected..

  The general stalls  training is inadequate and even likely to cause erroneous responses. Nev

Hence I think there should be a lot more slow speed training......

[djpacro]

14 hours ago, APenNameAndThatA said:

But my instructor said that if you put in forward elevator when you are inverted in the autorotation you might stay inverted. 

 

The autorotation stage is a mystery to me. And my instructor literally does not know when the stall ends and the autorotation starts. 🤷‍♂️  I brought that question up here before and no one else seemed to either.  

 

Suggest that you try another instructor.

Reading CASA AC 61-16 may assist.

14 hours ago, facthunter said:

The Decathlon probably has Frise ailerons ..... There's a big difference from some planes to others and you should know what's specific to the type. You are not supposed to be test pilots.  Nev

Totally agree with that bit except about the Frise ailerons.

 

[facthunter]

What form would that take? It's too broad a statement. What specific skills are you developing? Most just avoid and awareness/ information would help.. Nev

[facthunter]

My Citabria had Frise ailerons so I presumed the decathlon has also. I personally don't like them on an aerobatic plane. My usual spin entry is with out of spin aileron. (Anything to hasten the full spin.).. Nev 

[facthunter]

PenName .. IF the plane is not stalled it won't be autorotating.  A spinning plane will not gain airspeed without it becoming unstalled. either Partially or fully. These basics have to be understood. Spin OR Spiral. You treat the TWO differently. You will not do it right. IF you don't know and the whole exercise is Bl@@dy dangerous. Some planes will fall out of a spin if you just take your hands off the controls. Others will spin happily till they hit the ground.. During the recovery you will probably be in a fairly steep dive and THAT too must be handled correctly.  Nev

[Garfly]

Certainly, Slow Flight is well emphasised in the UPRT course offered by Ozaeros (the outfit set up by David J Pilkington - our own djpacro).

 

http://ozaeros.net.au/wp-content/uploads/2013/02/UpsetRecoveryCourseOverview2014.pdf

 

BTW, the Kindle version of djp's book can be had online for a few bucks. A great read for any pilot.

 

http://www.ozaeros.com.au/

 

 

 

 

 

Edited December 17, 2021 by Garfly

[facthunter]

Since the mid 60's, planes suitable to teach these skills have diminished markedly, and with it People who have considerable experience in those areas. CASA reacted to this by emphasising  wing drop incipient spins etc Picking up dropped wings is scary stuff with people who HALF understand what's happening. The old adage "A little knowledge is a dangerous thing" has relevance.. You think you will be able to handle it. Normal loss of altitude is about 250 feet for you recover from a stall. I keep getting told.. Well, in a lot of situations that means you may be dead. Loss of control at low altitude is still happening. . Should something be done to help rectify this?    Nev

[Garfly]

1 hour ago, facthunter said:

 Loss of control at low altitude is still happening. . Should something be done to help rectify this?    Nev

 

Yes, but it's not like nobody's tried:

 

https://www.faa.gov/newsroom/fly-safe-prevent-loss-control-accidents-0

"Fly Safe:

Prevent Loss of Control Accidents

Monday, July 6, 2015

The FAA and general aviation (GA) groups’ #Fly Safe national safety campaign aims to educate the GA community on how to prevent Loss of Control (LOC) accidents this flying season.

 

What is Loss of Control (LOC)?

A Loss of Control (LOC) accident involves an unintended departure of an aircraft from controlled flight. LOC can happen because the aircraft enters a flight regime that is outside its normal flight envelope and may quickly develop into a stall or spin. It can introduce an element of surprise for the pilot. Contributing factors may include: poor judgment/aeronautical decision making, failure to recognize an aerodynamic stall or spin and execute corrective action, intentional regulatory non-compliance, low pilot time in aircraft make and model, lack of piloting ability, failure to maintain airspeed, failure to follow procedure, pilot inexperience and proficiency, or the use of over-the-counter drugs that impact pilot performance.

Did you know?

• Approximately 450 people are killed each year in GA accidents.
• Loss of Control is the number one cause of these accidents.
• Loss of Control happens in all phases of flight. It can happen anywhere and at any time.
• There is one fatal accident involving LOC every four days.

Message from FAA Deputy Administrator Mike Whitaker:

The FAA and industry are working together to prevent Loss of Control accidents and save lives. You can help make a difference by joining our Fly Safe campaign! Each month on faa.gov we’re providing pilots with a Loss of Control solution developed by the team of experts. They have studied the data and developed solutions – some of which are already reducing risk. We hope you will join us in this effort, and spread the word. Follow #FlySafe on Twitter, Facebook and Instagram. I know that we can reduce these accidents by working together as a community."

 

And ...

 

 

https://iflyamerica.org/safety_plan_for_loss_of_control.asp

"Pushing the Envelope A Plan of “Attack” for Loss of Control Source: FAA Safety Briefing, May/June 2018 by Tom Hoffmann “... The pilot’s failure to maintain adequate speed while maneuvering to land, resulting in an aerodynamic stall.” It is an all-too-common probable cause statement found in literally hundreds of National Transportation Safety Board (NTSB) accident reports. In many of these cases, the pilot simply asked more of the aircraft than it could aerodynamically provide. These scenarios are also indicative of the types of inflight loss of control (LOC) accidents that have plagued the GA community for decades and have remained the elusive white whale of the aviation safety industry. But LOC accidents — your days are numbered!   ...  Solving the LOC equation is by no means an easy task, nor is it prudent to believe in any type of silver-bullet solution. There are many variables and underlying factors leading up to a LOC situation (distraction, weather, fatigue, lack of proficiency, etc.), but in most cases it boils down to one simple element — proper energy management. The key is figuring out the most effective way to help pilots better recognize their aircraft’s energy state and alert them when life-saving intervention is needed. Short of having something reach out and grab a pilot by the collar, angle of attack (AOA) indicators fit the bill nicely in terms of augmenting airspeed information and providing energy state awareness in critical situations."

 

 

Even CASA's path is set towards good intentions on the subject:

 

 

https://www.infrastructure.gov.au/sites/default/files/documents/national-aviation-safety-plan-2021.pdf

 

"The Australian National Aviation Safety Plan 2021–2023

[Excerpt:]

Operational Roadmap

1. Improve the safety of Australian aviation operations across all sectors

1.1 Mitigate contributing factors to CFIT accidents and incidents. 

1.2 Mitigate contributing factors to LOC-I accidents and incidents. 

1.3 Mitigate contributing factors to Mid-Air Collisions accidents and incidents. 

1.4 Mitigate contributing factors to Runway Safety (Excursions and Incursions) accidents and incidents. "

 

 

But maybe the best we Sunday flyers, can do to save or butts is follow PenName and go arrange to have some of what he's having.

Edited December 17, 2021 by Garfly

[Thruster88]

I like the defined minimum manoeuvring airspeed idea. DMMS is 1.4 times stall speed, it is also best climb and best glide for most light aircraft. If we dont fly our aircraft below this speed it will not get upset unless we are intentionally doing something stupid.

 

Light aircraft rarely depart controlled flight in cruise,  it nearly always happens at a height at which a recovery is not possible. Fly the aircraft at the correct speeds at all times and live a long life.

 

There has been two departure stalls involving RAAus aircraft in the last two weeks, both aircraft badly damaged but only luck prevented serious injuries or death.

[APenNameAndThatA]

11 hours ago, Student Pilot said:

I don't think there is any need for much more than a couple of spins in training. A lot more should be done on slow flight and slow manoeuvring so you know the aircraft and how to avoid stall/spin.

That would be true for someone who is not as scared. 

[APenNameAndThatA]

8 hours ago, djpacro said:

Suggest that you try another instructor.

Reading CASA AC 61-16 may assist.

Totally agree with that bit except about the Frise ailerons.

 

I don’t understand the bit about getting another instructor. And I googled it and I dont understand the bit about Frise ailerons. When I was spinning the Extra, I used opposite stick and rudder directions, so it was not just the instructor’s way of doing things. 

[APenNameAndThatA]

8 hours ago, facthunter said:

PenName .. IF the plane is not stalled it won't be autorotating.  A spinning plane will not gain airspeed without it becoming unstalled. either Partially or fully. These basics have to be understood. Spin OR Spiral. You treat the TWO differently. You will not do it right. IF you don't know and the whole exercise is Bl@@dy dangerous. Some planes will fall out of a spin if you just take your hands off the controls. Others will spin happily till they hit the ground.. During the recovery you will probably be in a fairly steep dive and THAT too must be handled correctly.  Nev

I am very aware of the difference between spiral and spin (airspeed) and recovery (unload then ailerons vs rudder then stick forward). But I don’t mind being reminded. In very high stress situations, perception alters, so the obvious things (noise, control weight) might not be obvious. 

 

Too, what is it with Frise ailerons? does the increased drag of the up-going aileron negate the benefit of the pro-spin input? 

[facthunter]

Yes it does The plane just sits there till you put the ailerons to central.  Frise gives a lot of drag. it's better to use active rudder than have that effect. Nev

[djpacro]

11 hours ago, APenNameAndThatA said:

I don’t understand the bit about getting another instructor. And I googled it and I dont understand the bit about Frise ailerons. When I was spinning the Extra, I used opposite stick and rudder directions, so it was not just the instructor’s way of doing things. 

Apologies, I must've misunderstood your comments about your instructor.

 

The effect of aileron in a spin for the Cessna (which has Frise ailerons) is significantly different than for the Decathlon, the opposite effect in some situations. (Cessna published a comprehensive document on spinning.)

[Student Pilot]

21 hours ago, djpacro said:

Suggest that you try another instructor.

Reading CASA AC 61-16 may assist.

Totally agree with that bit except about the Frise ailerons.

 

I heartily disagree, reading any CASA rules/recommendations/regs will only confuse 

[APenNameAndThatA]

22 hours ago, djpacro said:

Apologies, I must've misunderstood your comments about your instructor.

 

The effect of aileron in a spin for the Cessna (which has Frise ailerons) is significantly different than for the Decathlon, the opposite effect in some situations. (Cessna published a comprehensive document on spinning.)

no probs

[facthunter]

Yes there's wide variation in the effect as the design varies, The principle is the forward section creates DRAG  at the lower rear surface when THAT aileron is UP and the plane Yaws less. when you apply aileron   The Cessna also has a fair amount of wing washout that reduces tip stalling. The high wing Cessna's behave well at low speeds but they can still bite if you push them enough and when you're heavy you don't need more drag in  say a 172. which tends to be underpowered.if you fill all seats Nev

[Roundsounds]

On 16/12/21 at 9:29 PM, APenNameAndThatA said:

I did spins today in a Super Decathlon. It turns out that spins speed up after the first couple of turns and it gets a bit physically intense. Its very different to gracefully autorotating.

 

And what about that bit when you put in full opposite rudder and stick forward and nothing happens? You just keep spinning. 😆 A second or two later, the spin starts to slow, but nobody seems to mention that bit where nothing changes for a while. 

 

And full power (180 hp engine but only 23” manifold pressure at 6000 ft) stalls? I thought the plane would do some sort of snap flip into a vicious spin but not much happened. 

 

I kept the wings level, in a stall, with the rudder for a couple thousand feet. Indicated speeds about 60 kts, and 1500 fpm. 

 

Its no humble brag that I still find stalls frightening. Like if I just hold the stick back, everything is still a bit too overwhelming to work out if what I have ended up in is a spin or a spiral. The uncertainty and waiting for a wing to drop (which is a catastrophe and must be avoided at all costs, right?) and what mysterious thing might happen next is what is anxiety-provoking as far as I can tell. 

 

Also, before I did this, I spent 2.5 months, going on about 90 rides at Movie World and Dream World so I would be game to do the stuff to make me game to stall. That was a while ago now.  

 

On reflection, now I know you can put in down elevator as soon as you put in opposite rudder in a spin, maybe you can do that in stalls. But my instructor said that if you put in forward elevator when you are inverted in the autorotation you might stay inverted. 

 

The autorotation stage is a mystery to me. And my instructor literally does not know when the stall ends and the autorotation starts. 🤷‍♂️  I brought that question up here before and no one else seemed to either.  

You’re overthinking this whole thing. Each aeroplane type behave differently, stall and spin entry / recovery procedures will be found in the flight manual.

Don’t think about down elevator, think in terms of reducing angle of attack. If you’re in an inverted spin you’ll need “up” elevator to reduce the angle of attack. 
Again don’t stress, you should seek proper instruction in each aeroplane type. 

[APenNameAndThatA]

6 hours ago, Roundsounds said:

You’re overthinking this whole thing. Each aeroplane type behave differently, stall and spin entry / recovery procedures will be found in the flight manual.

Don’t think about down elevator, think in terms of reducing angle of attack. If you’re in an inverted spin you’ll need “up” elevator to reduce the angle of attack. 
Again don’t stress, you should seek proper instruction in each aeroplane type. 

I don’t agree with the over thinking bit. Thinking about things is part of understanding and of mental rehearsal. Both are important.

 

You are right about the inverted spins. I never had any problems with them though. 

[naremman]

"Yes there's wide variation in the effect as the design varies,"  Nev

 

"Each aircraft type behave differently, stall and spin entry": Roundsounds.

 

Two sage gentlemen. both finding the same page of the the hymn book.

 

In comparison. I can modestly claim intentional spinning in five aircraft, yet the outstanding facet is just how different the five aircraft are in a developed spin, and what worked for one aircraft would have called for the undertaker in another.

 

The outstanding difference would have been in two de Havilland aircraft. Initially the Chippie, and a very experienced ex Army pilot Instructor intoning "until you understand the stall/spin characteristics we a'int going further". Learning overdrive. Thence onto the Tiger Moth. If ever you wanted the to nominate the aircraft with the definitive stall/spin I would put the Tiger at the top of the list. My instructor stated that he was convinced he heard laughter from back seat of the Tiger in the first spin. "Can we do it again?"

 

After the de Havilland experience I was in the UK and was keen to experience a Beagle Pup. I have an hour in my logbook. Do I remember it: yes, but probably for not the most beneficial reasons. A Chippie type entry to get into an established spin, poor rudder authority for a prolonged recovery, and the forward stick transitioned promptly with our heads on the cockpit roof as it tucked under!

  

The aircraft that I have most experience in spinning is the Airtourer, which creates it's own category, hard work to gain a crisp clear into it's entry, but rather than airspeed stable, it is an accellerating spin, hence the two turn limitiation.  John O'Halloran, a former ARDU Test Pilot and recently retired Test Pilot of Cathay Pacific has an extensive article, with input from Henry Millicer , in the Airtourer Assciociation website of the Airtourer's handling characteristics

 

Some Cessna products are cleared for spinning. Aerobats clearly, and some C150/172 conventials. Aerobat, maybe, pass on the rest. I have been flying for long enough to remember the departure from control of too many C150 engaged in mustering operations with tragic results.

 

Sadly it is pilots with spin training that are too represented in spin accidents.  That the late David Walker, a well credentialled CFI spun a Ryan in remains burned in my brain

 

A fair proportion of aircraft today have very benign stall characteristics, which induces a comfort feeling approaching the stall. The first time I flew a Warrior 2 I turned to the Instructor and said:" you are not teaching people to fly in this are you"? My introduction to RAA flying was in a J160 and despite banging the stick back onto to the control stops we could not induce a nose drop. The early Cherokees would have a light in the middle of the panel light up, no aerodynamic warning, and you would pass the descending brick.

 

I have always maintained that advanced stall/aerobatic experience is to alert the pilot that aerodynamic stress is approaching and do something about it smartly.

 

Airspeed is life. What is it about, airspeed , altitude and brains, and two are necessary?