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Air Asia Indonesia Lost Contact from Surabaya to Singapore

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Air Asia Indonesia Lost Contact from Surabaya to Singapore

Old 11th Feb 2015, 01:05
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Vilters

while some of this is true, you are making things harder than you need to.

Pushing forward on the control stick, and with the airbus, trimming forward too should be enough.

While engines can bring the nose up, having the engines providing thrust would allow for a better acceleration.


And while the gear may shift things, the drag later on would reduce acceleration.

Stick forward, trim forward, bank if you can't get the nose down, but all the other stuff makes a recovery difficult on the other side.
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Old 11th Feb 2015, 01:12
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You talk about banking.
In a fully developped deep stall, you have no aileron control any more, no rudder or elevator control any more.

All you have left is use assymetrical trust to get the nose to turn, bank, and eventually drop. Usually one wing unstalls first, and you flip past 90° of bank (the cartwheeling part) but you have the nose down.

Regain speed, and regain air movement over you controls.

Regaining speed is regaining airflow over the control surfaces, speed is life.
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Old 11th Feb 2015, 01:25
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@skyhighfallguy

Your comments are correct. And an unstallable aircraft should not stall. But.

But see?
You are already thinking about the recovery part, before you got unstalled.

FIRST get the nose down. FIRST break the stall.

In a fully developped deep stall, you are dropping like a stone in this thin air, there is little time.

FULL nose down on the stick, wait, then nose down on the trim, wait, but not too long, then chop power, then drop gear, there is little time left by now, and you still have to start the recovery part....and you need altitude for that too.

If nothing helps? Asymetrical power and prepare for (perhaps) a flip/cartwheel, when one wing stalls unstalls before the other wing, perhaps even passing inverted.

The wing drop/flip part is clearly visible in the other video about the ATR. The assymetrical stall roll rate is "fast", and you have NO airspeed over your control surfaces yet to counter it. You have to wait for the speed to come back before you can start regaining control of the roll rate and the nose.

Last edited by Vilters; 11th Feb 2015 at 01:36.
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Old 11th Feb 2015, 01:45
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The unstallable stall

Vilters, I don't mean to challenge you, rather to note there has been some lengthy previous conversation--correction--broadsides right here regarding whether a deep stall of long duration was even possible not to mention probable. If, ensconced as many forum readers are in the quiet comfort of their homes, with either a hot or cold tall one within arms reach, such a conversation could consume group minutes or in some cases hours, not the paltry time available to the pilots in question.

>You are already thinking about the recovery part, before you got unstalled....

Exactly the emphasis one is taught in the present day.
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Old 11th Feb 2015, 02:11
  #3185 (permalink)  
 
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If nothing helps? Asymetrical power and prepare for (perhaps) a flip/cartwheel, when one wing stalls unstalls before the other wing, perhaps even passing inverted.
Yaw rates in a stalled jet aircraft are extremely hazardous. Just asking for a spin.
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Old 11th Feb 2015, 02:36
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Lookleft
I still can't accept that an ex-airforce fighter pilot has 20,000 hours. What age did he join the airline and how many hours did he have when he left the airforce? My point being he may not have been as experienced as others are suggesting. If he did have that many hours at age 53 after an airforce career then he was flying a lot of hours every year.
Sounds like he had to work his way up in both the Air Force and Airlines. No fast track Academy or short cuts.
Iriyanto joined the air force for a 10-year service term, climbing the ranks to first lieutenant flying F-16 and F-5 fighters.
Iriyanto worked for PT Merpati Nusantara Airlines as an instructor for Fokker 27 aircraft (Twin Turbo prop).
He joined AirAsia after his then-employer PT Adam Skyconnection Airlines ceased operations in March 2008 following three plane crashes in a year.
Of his flying hours, 6,053 were with AirAsia.
more than 20,000 flying hours under his belt in a career that spanned three airlines

Iriyanto “is a good flier, procedural, and considered outstanding,” Hadi Tjahjanto, a spokesman for the Indonesian Air Force who trained with Iriyanto, said by phone from Jakarta before the news that debris had been found. “He was classified as a fighter pilot and acted as an interceptor should there be suspicious planes around. So speed in taking action is essential.”
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Old 11th Feb 2015, 06:09
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Windshear

I'm confused.

FCOM:

The Flight Augmentation Computers have three main functions:
  • Rudder trim
  • Rudder travel limits
  • Yaw damping inputs
  • Alternate yaw
  • Flight envelope and speed computations
  • Wind shear detection
Can it be said that the FACs rely upon pitot tubes (three of them, but nothing else) to determine the aircraft's airspeed?

Can it be said that in the case of double FAC failure that the aircraft will revert to alternate law -- with reduced protections?

Can it be said that the FACs might interpret (misinterpret) rapid airspeed fluctuations known to be associated with crossing shear layers / windshear, and implement overspeed protection trimming the aircraft nose up?:


Flight crew operating manual(FCOM)and standard procedures
•Until mid 2013, there was only a descending aircraft over speed prevention checklist That checklist included disconnecting the autopilot and raising the aircraft nose.Use of that checklist in the cruise was inappropriate because it could result in a significant altitude exceedance at high speed and manually flying the aircraft at high speed and high altitude was not practiced often.
•Airbus published new flight crew operating manual (FCOM) procedures for overspeed prevention and recovery. Both checklists commence with AP (autopilot) :KEEP ON
. A newsletter distributed to company flight crew contained the new overspeed recovery FCOM but not the overspeed prevention FCOM.
•If the autopilot remained engaged during an aircraft overspeed flight envelope speed protection is provided in the relevant AFS modes, resulting in a nose up order within the limit of the autopilot authority to reduce or stop the airspeed increase
Can it be said that once a UAS event is triggered, the AP disconnects but A/THR remains active, the FDs remain active and the FAC / protections remain active (to the extent the FACs have reliable - or unreliable information?)

In the event of rapid transient true overspeed while crossing shear layers associated with thunderstorms, is it reliable to depend upon FACs and pre-programmed overspeed protections? Taken a step further, can perceived overspeed protections affect the SS nose down / manual pitch trim down a pilot might apply?

After entering alternate law, due to UAS prompting dual FAC disagree / failure, at what point does the FAC drop itself out?

Automatic pitch trim stops trimming nose down momentarily at VMO or MMO. This provides a momentary pitch up when high speed stability is active, but automatic trimming will continue if over speed is continued by pilot. An aural "crickets" warning will be heard at VMO plus 4 knots or / MMO plus .006M.
High Speed Stability may or may not be available in alternate law depending on the type of flight control failure.
If a zoom climb/ambient air temperature change/violent updraft, etc., resulted in the aircraft being out of its envelope, in 'approach to stall' does the FAC drop itself out after it has sensed the aircraft approaching a perceived stall speed or does the Augmentation Computer still try to 'help':

The VSW is defined by the top of a red and black strip along the speed scale. It represents the speed corresponding to the stall warning, as computed by the FACs.
When do the FAC / protections cease having any effect on pilot inputs / pilot directions?

Is there any way to turn them off -- if, say, you were already close max alt, nearing coffin corner/impending stall, yet encountering more turbulence/windshear and HAL wanted more nose up?

When the A320 encounters wind condition changes in the cruise similar to shear, the airspeed can increase quite quickly and this is not a rare event on the A320. During flights between Melbourne and Gold Coast/Brisbane airports, this windshear/wind speed change and potential overspeed situation is not uncommon as the aircraft transits the southern jetstream.
AIRBUS SAFETY LIBRARY
II.2 Defining Windshear

Windshear is defined as a sudden change of wind velocity and/or direction.
Windshear occurs in all directions, but for convenience, it is measured along vertical and horizontal axis, thus becoming vertical and horizontal windshear:

Vertical windshear:
−Variations of the horizontal wind component along the vertical axis, resulting in turbulence that may affect the aircraft airspeed when climbing or descending through the windshear layer
−Variations of the wind component of 20 kt per 1000 ft to 30 kt per 1000 ft are typical values, but a vertical windshear may reach up to 10 kt per 100 ft.

Windshear conditions usually are associated with the following weather situations:
•Jet streams
•Mountain waves
•Frontal surfaces
•Thunderstorms and convective clouds
•Microbursts.
Influence of Windshear on Aircraft Performance The flight performance is affected as:
• Headwind gust instantaneously increases the aircraft speed and thus tends to make the aircraft fly above intended path and/or accelerate

• A downdraft affects both the aircraft Angle-Of-Attack (AOA), that increases, and the aircraft path since it makes the aircraft sink

• Tailwind gust instantaneously decreases the aircraft speed and thus tends to make the aircraft fly below intended path and/or decelerate.

Windshears associated to jet streams, mountain waves and frontal surfaces usually occur at altitudes that do not present the same risk than microbursts, which occur closer to the ground.
I don't see thunderstorms there....
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Old 11th Feb 2015, 06:43
  #3188 (permalink)  
 
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Heavymetalist

How do you define "oldies"?*Apparently 20'000 hours did not help in this incident:

Flybob explained the advantages of experience and wisdom that come with it succinctly.Try and put a compliment of two non experienced modern pushbutton automation SOP regurgitating robotic crew in a cockpit with no experienced hat supervising their oeration and a severe abnormality cocks up! Something similar or worse than AF447 might transpire. Where experience comes in is how it can reason with thise SOP and know when it is wiser to deviate from them to be able to save the day..and have the confidence and executive powers to implement the judgement effectively...and. if you ask the youg lad or lass on the side they might be so out of the loop in catching up to what's going on...it makes them even wonder if they are qualified enough to be sitting in that flight deck!Most likely the Captain has to explain through the actions to bring the youngster upto speed.
Whoever quotes KLM/Pan Am accident..it was a concoxion of various causal factors amongst which admitedly the KLM Capt was one of them.Missed radio communication and foul weather with incorrect ATC phraseology all played a part..both KLM PanAm and the Tower made mistakes that day and the swiss cheese was penetrated.
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Old 11th Feb 2015, 06:45
  #3189 (permalink)  
 
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Vilas

Apart from the 3 primary controls you mentioned, they also have spoilers, which are very effective for lateral control. They had airspeed, so they would have been effective.

I don't think the poor guys knew they were in a stalled condition, period. Misdiagnosed as you mentioned. There appeared to be no attempt to get the nose down. You would have noticed on the way down, they did have lateral control. I noticed when bank was evident, intentional or not, the nose did lower. So from that I take it they would have known how to get the nose well below the horizon, should they have wished.

The stall behavior data appears to be available, so it should be programmed into simulators. Unfortunately not the recovery data.

Just my observation.

Last edited by Sop_Monkey; 11th Feb 2015 at 07:22.
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Old 11th Feb 2015, 08:19
  #3190 (permalink)  
 
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For those advocating spin training in light sep and mep, all very well and good.... but...
This would involve time out from line flying and the accountants will say ... no!
A large number of airlines are very rigid in their application of sops this means 400' ap on, minimums ap off, or autoland. Hand flying is not encouraged full stop. Far less in RVSM .
The result is that basic hand flying skills are rapidly degraded, therfore how long will the stall training be valid for ? To be of any use it needs at least annual refresher and this leads us back to the accounting department.

Stalling. The primary reaction has to be the reduction in AoA. If you apply full power/toga it is more than likely you will get an uncomanded and uncontrollable pitch up.
No one flys airliners close to the stall deliberately, therefore the reduced speed has gone unnoticed. The aircraft will be on AP and will therefore have trimed for the slowing speed. When the AP gives up you have an almost full nose up trim, add in power and it will surprise surprise pitch up.
Witness: AF, Colgan, Bournemouth 737 etc
Application of power has to be applied relatively slowly along with rapid trim nose down. But first reduce AofA!
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Old 11th Feb 2015, 08:53
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Originally Posted by Lookleft
I still can't accept that an ex-airforce fighter pilot has 20,000 hours. What age did he join the airline and how many hours did he have when he left the airforce? My point being he may not have been as experienced as others are suggesting. If he did have that many hours at age 53 after an airforce career then he was flying a lot of hours every year.
He left the airforce in 1994 and then joined Merpati Airlines flying F27 and F28s before joining Adam Air flying 737s. He later joined Air Asia after Adam Air foldered. Air Asia Indonesia started with a fleet of 737s in the early days, before they went to an all A320 fleet.
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Old 11th Feb 2015, 08:59
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For those advocating spin training in light sep and mep, all very well and good.... but...
I've said it before an will say it again: we don't need spin training, per se. IMO all we need is good hand-flying IF skills. We should then be able to fly safely when the AP spits the dummy or diagnose the situation and recover (eg AF447, which wasn't in a spin). We all go to the SIM every 6 months. A 1/2 hour, non-jeopardy, of flying around on raw data (including enjoying oneself eg wingovers, barrel rolls) together with eyes-closed U/A recoveries would go a long way to improving our ability to take control of the aeroplane when the situation goes pear-shaped.

Of course the bean counters will go ape; the regulatory authorities should have the balls to regulate it into the SIM programs; then it's a level playing field for all.
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Old 11th Feb 2015, 09:21
  #3193 (permalink)  
 
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Although this thread is about the lost air asia aircraft and we still do not know what happened in detail, one discussion focused on stalls and the way to recover from those.

Vilters
I am a pilot.
Flew light to medium, even have a BFM (Basic Fighter Man) hr in an F-16B, and yes we pulled the whole 9G's a couple of times.

No, all those "Thousands of hrs" airline pilots do not need a single extra hr in a simm. NOT a single hr.

They need "REAL" seat time in a Cessna 152, a Pitts, or a Cap10.

They "need" some "REAL" and "DIE HARD" stalls to cope with, not in any simm at all, but in real life.

Where their bottoms come loose from the seat.
Where the break drops the nose deep and the wings fall ways from you.

I'v had "real" pilots turn white as paper.

I'v had guys shouting and screaming; sweating and strugling.

All they ever did was; "Stay away, stay away, recover before the stall."

Well, I fear the results speak for themselves.

And then do a full deep stall in a twin.
And teach them to cartwheel out of the stall. Full rudder and Full power on one, chop the power on the second, and cartwheel overhead out of the stall.

Then you will have pilots that start to understand stalls.

You might see some pilots turned WHITE, but you"ll have better pilots.

You can put them in a sim for weeks, nothing will ever change.
I do agree with a lot what you are saying.
Doing stall approaches and stalls and revovery from those in the sim might be usefull as an procedural thing, but it will never be able to replicate the physical behaviour of the aircraft and its influence on the human brain. To understand stalls and their influence on the human body and brain you have to have first hand live expierience of of such a situation and the necessary recovery steps, as the recovery will be even more uncomfortable than the stall itself.

Recognizing the stall:
The stall entry might be smooth and gradual with modern FBW aircraft, preceeded with some airspeed decrease and increase in pitch, maybe some vibration, and then the ship does not follow the commands like it should, descent rate will increase while some wing drop might occcur. That is unusual, but it is not asociated with alarming loadfactor changes or violent maneuvering. Therefore stall warnings should always be treated as real unless proven otherwise.

Breaking the stall:
Already the first step for the recovery, to reduce the AOA by bringing the nose close to the flightpath is a maneuver never performed before, the change of the loadfactor from 1g to 0g and the immidiate never before expierienced sensation of weightlessnesss of the body will make one sweat. The arm on the SS will no longer be supported by the armrest, or the arm on the steering horn will not rest on the upper calf, Legs will not stay on the floor by themselves, papers and stuff flying around, a completely differnt situation from the one just seconds before. Combine that with the need to act against long trained reflexes, to disregard the altitude loss, to disregard the bank angle, to drift off from the intended course, to pull power levers back instead of advancing them and to deliver the passengers a load of discomfort and even the risk of severe injuries. The next task is to maintain this input long enough, which will most probably lead to a never expierienced nose down pitch position, which in connection with the 0g loadfactor will give the sensation of surreal acceleration.

Recovery to normal flight attitude:
When the stall is broken and flying airspeed is regained the recovery has to be initiated immidiately to prevent an overspeed, but with enough care in order not to overstress the airframe. Power has to be adjusted to manage available energy. Secondary stalls are a common occurance in stall encounters, therefore concentration should focus on regaining a level pitch and bank attitude and stabilize the normal aircraft parameters. Regaining lost altitude, regaining navigation and informing ATC are of secondary importance to attitude and speed.

CRM under stall encounters
Both crew members have to be trained to the same standard, that the PNF understands and accepts the maneuvers flown by the PF and asists with the appropriate informations, speed being the most important of all, while a myriad of warnings are blaring and the ECAM puts out messages faster than one can read. Out of control response was a briefing item for every flight with my weapon system operator, so he would know what my plan of action was.

Look at the posted BEA video, how fast and gradual everything happened, bad that it does not incorporate the nz graph. The AF447 crew failed in all of the above parts, they had no chance.

Wishlist for training
It is not a situation one wishes to encounter unprepared. Most important would be a thorough introductionary course with lessons, sim training and some real stall demonstrations / practice and recoveries. A refresher course should be mandotary when changing type or after elapse of a predetermined timeframe.


I do not agree in the application of lateral control inputs by flight controls or asymetric thrust. In a stalled situation those inputs are pro spin inputs like Machinbird correctly says, and no skygod will get an airliner out of a spin. Those tails on transport aircraft have mighty control surfaces, correct usage (trim and elevators) should give enough authority to reduce the AOA.

Thanks to the mods in allowing these discussions, although we do not know yet if they are relevant to this thread.

Last edited by RetiredF4; 11th Feb 2015 at 12:19.
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Old 11th Feb 2015, 10:34
  #3194 (permalink)  
 
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Then you will have pilots that start to understand stalls.
You might see some pilots turned WHITE, but you"ll have better pilots.
You can put them in a sim for weeks, nothing will ever change.


Great fun; been there, done it; great idea, BUT......

Sadly the airlines philosophy is "sim time costs money and it is only necessary to perform the legally required basics." They have then covered their backside. Sim costs money; pilots not in a/c costs money; hotels travel to/from costs money etc. etc. Their prime idea is to train their pilots to keep well away from the dangerous part of the envelope. SOP's will ensure that. Meanwhile I hear the students spouting the new TEM mantra before any phase. What are the threats? If they can't perceive any they invent them. No-one ever says Mother Nature & Gravity. You are in a hostile environment where you ain't supposed to be. The shark is trying to bite your tail and the crocodile is waiting to pounce on the unsuspecting. If you put your foot in the water and get snapped at you need to know what to do. That's the thinking of the suggestions above. (you might see some pax turn WHITE, and you may not see them again, but they'll be alive.) I doubt the XAA's will enforce such items, and no airline will do it of its own initiative. They will quote cost/risk management and say how many times in a career will a pilot need such skills (risk) and what would it cost over a career to keep them up to speed? Every 3 years I jumped through the UA upset program. Rubbish, but box ticked. All the pilots on my B737NG I spoke to, including the trainers, did not know there is a stick nudger. (At least there was when I first went on type. I used to demo it.) Now they only recover at the shaker. I also admit that before Boeing introduced the new (old) 'unstall the wing first' idea I used to teach it. Attitude first then power. Split second, no more. Since when did Seattle or Toulouse redefine aerodynamics? I did also demo the stick-shaker power only recovery with autopilot in ALT HLD. It was scary, but educational. I did this at various levels to show the capabilities of power over aerodynamics and the effect of thrust reaction at different levels. It was a full in-depth exercise. Took a while, but once seen never forgotten. Then a new syllabus was imposed and job done in 10 mins to minimum requirement.
So don't hold your breath waiting for change. A few more enlightened C.P.'s & HOT's and CFO's might help. Best o' luck.
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Old 11th Feb 2015, 11:59
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@RAT 5

Interesting that you mention TEM. Part of TEM is the ability to handle things when they go south and that definitely includes autopilot malfunctions. For reference: http://flightsafety.org/files/maurino.doc

TEM and CRM are, IMO, useful concepts in theory as conceptual frameworks for many of the issues under discussion here. What many posts have discussed is that they are worthless without basic airmanship skills. In other words, recognizing autopilot/autoflight malfunction as a possible threat, while not equipping pilots with the handflying skills needed to react properly to that threat is tantamount to recognizing a threat without giving pilots the skills to counteract that threat.

I'm a big believer in CRM and will defer to Al Haynes on his opinion of the concept, which is far more eloquent and rooted in experience than mine could (hopefully) ever be, though I have found over the years that CRM has made me a better pilot by giving me a concept through which I can learn even as I age. Those who point to Tenerife as the primary motivator for CRM haven't read their accident reports. UA 173 in 1978 comes to mind; there are others.

With respect to TEM, I think we have a concept that is sound in theory as a way of looking at things but which comes up short in execution. TEM should not be a mantra, it is a way of looking at risk management. Where I think things may be out of alignment is that some may be capable of reciting the concept without the skills to back it up and in that respect, you're correct, it has become a mantra rather than a conceptual framework that requires judgment and airmanship which with to back it up.
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Old 11th Feb 2015, 13:26
  #3196 (permalink)  
 
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Ad som drag?

Vilters /RetiredF4 and others.

My exsperience with stalls is from gliders. There you could absolutely stall the plane - and induce a wing (and nose) drop by applying some rudder. It would get the plane out of stall and into a steep dive - the recovery was high speed and involved some positive g.

Along these lines:
Would it be OK to ad some drag (extend the weels) - both to get the nose down - but also to have some extra drag so the plane will not accelrate that fast during steep dive phase of stall recovery?

For the traing part. Would it be an idea for professional pilots to take a few starts in a glider with a acro-glider instructor - just to "feel the stall forces" and get some first hand stick and rudder practice in this field.

Also - Let say you start in a fully deep stall with little or no authority on the control surfaces. What are really your options? Elaborate on that. The airstreams is coming from below allready and as you start diving your speed downwards increase but you may still be stalled? How deep dive would you need at minimum to get out?

What about spoilers and even 5-10 flaps - slats. What would it do? .
Also from my training as a glider - the diving spin was not that feared - it was rutine practise. The one feared was the "flat-spin" - Could a one side engine power induce a flatspin" - Could rudder induce a flat spin. Can you be shure one wing drops to induce dive? Also, since at the stall the plane is generally at a low speed - will the rudder really have the capability to break the plane if used to hard

To the extreme - could you unstall a plane in a deep stall by applying reverese thrust moderately?
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Old 11th Feb 2015, 13:59
  #3197 (permalink)  
 
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Also - Let say you start in a fully deep stall with little or no authority on the control surfaces. What are really your options? Elaborate on that. The airstreams is coming from below allready and as you start diving your speed downwards increase but you may still be stalled? How deep dive would you need at minimum to get out?
Another technique that may be useful is rocking the plane out of a stall. Sort of like rocking your car out of a slippery spot. But first, get that THS trimmed down toward a ~300 knot setting. You know where that is, right? (Assuming you are flying a jet aircraft )
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Old 11th Feb 2015, 13:59
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Apply 90 degs bank and no extra nose up elevator/trim the nose will drop, let me assure you. Weather cock, tail feathers...

As you said extend the gear, anything but unload the wings, whatever you do and get it pointing down hill. The gear and the speed brakes would help control the speed on the way down.

No real need to have asymmetric power, as it could cause extra complications.
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Old 11th Feb 2015, 15:11
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FBW aircraft and severe weaher penetration

Are FBW aircraft more susceptible to stalling when flying in severe weather? If so should it not be mandated that FBW pilots be given stall recovery training in the actual plane as part of base training as obviously sim training even if level D sim..hasn't been adequate. To ensure stall recovery in real flying.It can be practiced in clear weather but with certain simulated faults (system off..such as AOA and some probe heating off and remain with only the ISIS for reference to purposely disorientate the student but with Instructor able to view flt parameters and how the student is recovering.
I reckon it won't be long before we have another irrecoverable stalling accident by FBW aircraft flying through some ITCZ or other severe weather..if nothing is changed in training methodology. unless perhaps Airbus designs a STALL recovery button that works independently based purely on accelerometers and GPS..and when executed will retard thrust and auto pitch down like stick pusher and when speed builds up(based on GPS determined speeds do an auto recovery.Surely after designing a sophisticated FBW systen this should be simpler to design and incorporate by comparison?

Last edited by Trackdiamond; 11th Feb 2015 at 15:28.
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Old 11th Feb 2015, 17:38
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Stall recovery training and even spin recovery training is in the syllabus of most military training schemes. I did full developped stalls and spins in the T37 Cessna, and later recovery from some unplanned stalls in the F4. It never was routine, each of those planned or unplanned stalls were a challenge.

Let's concentrate on doing the recovery in the most simple way first, it will work in more than 90% of all those events. Reduce the AOA by applying nose down input and nose down trim, consider reducing power, but at least do not add power. When the aircraft is unloaded at about 0g, you are not stalled anymore. Now accellerate by gravity and if necessary by smooth power application to flying speed, while maintaining this loadfactor close to 0g. Level the wings to the nearest horizon, then start a controlled pullout to level flight.
It is a step by step procedure, one has to be patient to let the contol input become effective. Any kind of premature change of configuration, thrust or drag will change the whole equation again with consequences for the next steps.

Concerning the bank angle it would be a great achievement to let the bank angle develop by itself ( which it does anyway in disturbed airflow) and accept it as help in getting the AOA down instead to counter it.

Any bank steering input or assymetric thrust change might induce yaw and kick the aircraft into a spin. It does not have to be a flat spin, any spin for a normal crew in a big transport aircraft will be deadly. There is no time to check out how much yaw dampers or limiters are still working which might prevent such a spin entry. Keep away from these possibilities as long as possible.

Although gravity is a mighty force, it is easily countered by flying machines. If the power is used with caution in the recovery phase i see not much problem in doing a pullout without overspeeding or overstressing the airframe. Lets keep it simple, plan on keeping the gear and flaps where they are at the beginning of the event as long as possible.

I have not flown gliders, but they would not be my choice for stall recovery training. There are lots (cheaper than sim time) aircraft available to demonstrate the necessary steps and feel the unloads for recovery.

But fiinally it is not only a question of funds, it is also a question of will.
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