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He stepped on the Rudder and redefined Va

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He stepped on the Rudder and redefined Va

Old 10th Oct 2013, 02:43
  #341 (permalink)  
 
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Clandestino, does not Airbus teach pilots with loss of IAS that holding last attitude and power and getting out UAS checklist is the answer or do the French rely on Airbus automation? If not, we do it differently on the west coast. Works fine.
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Old 10th Oct 2013, 02:46
  #342 (permalink)  
 
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Of course if the auto pilot clicks off you need someone that knows how to hold an attitude and not just pull up.
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Old 10th Oct 2013, 03:01
  #343 (permalink)  
 
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flare pilot,

Yes, very different slat arrangement, it doesn't have slats. The 65 had a Raisbeck "supercritical" forward section grafted onto the basic wing. Super in "supercritical" meant one needed to be super careful in icing. Bit like the wing on the CL600 series--fine, if you followed the book in icing conditions. But, if the leading edge section had the least bit of contamination that created sonic flow, it stalled abruptly especially if a rapid rotation brought the wing to stall AOA in ground effect (IGE). Big steaming bowl of Not Good, see G650 accident and all the CL600 accidents. All abrupt, asymmetrical stalls IGE.

Last edited by galaxy flyer; 10th Oct 2013 at 03:02.
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Old 10th Oct 2013, 07:50
  #344 (permalink)  
 
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Playing the ball. Flare pilot, I'll quite happily eat crow if you can scan the relevant page from the flight manual and post here. I repeat SCAN the relevant page. Only because no one I've talked to has heard of it. Up to the challenge? Until then then.
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Old 10th Oct 2013, 09:20
  #345 (permalink)  
 
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roulis


But I understand that prudent formulation and choice of Davies, so long as pilot don't want to reckon some precisions... :
I’m really not sure what point you are trying to make here. If it is a plea for a mathematical definition of acceptable dutch roll characteristics then such things already exist and are used by engineers in the design stage to establish whether yaw dampers are needed (almost always they are) and to define the control laws under which they will operate. Search for lateral directional handling criteria and you will get a bucketful. (or MIL-F-8785C)
If you are looking for something to use in flight then I think that would not be very practical; besides which I am sure that pilots don’t need a set of memorised numbers to tell them that the aircraft is doing something they don’t like!


Why did Learjet not adopt Davies's method and stay wrong with the rudder use, and reversal use, and brutality use ?
I haven’t a clue! You’d have to ask the Learjet test pilots or whoever decided on that recovery technique.

Stopping the bad divergent oscillation is not all : probably your aircraft wants to play it again ! that divergence had a cause, and watching the motion quantatively helps to fly safe at home avoiding a new divergence with your jammed yaw damper...
I agree that in a divergent situation it may, probably will, happen again; but telling the pilot to watch the motion like a hawk to prevent build up of any roll oscillation is surely not the solution? In this regard prevention is better than cure.
Can we agree that a divergent dutch roll is only likely to build up if the aircraft is either naturally unstable in that mode or if the dutch roll is so lightly damped that inappropriate pilot inputs may drive it unstable? In either case the aircraft would be deficient against the certification requirements that call for it to be controllable without the use of exceptional piloting skills. Under modern certification rules (FAR 25.1309) the allowable probability of any system failure is linked to the consequences of that failure. So if yaw damper failure would result in a Hazardous situation, i.e. one :

which would reduce the capability of the aeroplane or the ability of the
crew to cope with adverse operating, conditions to the extent that there would be:
(i) A large reduction in safety margins or functional capabilities;
(ii) Physical distress or excessive workload such that the flight crew cannot be relied upon to perform their
tasks accurately or completely; or
(iii) Serious or fatal injury to a relatively small number of the occupants other than the flight crew.
then the failure probability would have to be Extremely Remote that is to say less probable than once in every 10^7 flight hours.
This being the case, I think that the introduction of quantified criteria for the pilots to monitor is not necessary.

The final object of certification is to do the aircraft safe for the wanted use. Today we have to increase air safety despite crashes statistics are getting better. All the crashes which can be avoided have to get progressively suppressed.
Well you won’t find anyone to disagree with those sentiments on this forum! But I have found over the years that if you have a problem it is best to attack the major contributors first. Today the major players in accident statistics by far are LOC and CFIT. The latter is being addressed and the rates are coming down, but I’m not so sure about LOC. There are a lot of things in there where better communication between the engineers and pilots would pay dividends, which is why I read with dismay some of the us vs them comments on these pages.
Even so, you would struggle to find any instance of an accident attributed to a divergent or neutral dutch roll characteristic. [I exclude the subject of this thread because the natural dutch roll was well damped (yaw dampers still operative) and because of the inappropriate control inputs]

Changing certification rules can perhaps help, and if it should help why not try ? Perhaps it could improve the speed of information from engineers to pilots ?
Alas! The one thing that has come out clearly in these discussions is the virtually complete exclusion of trained pilots from the certification rules. Until that blockage is removed there is, I fear, little chance that changing the rules would speed the passage of information.


(I know that you will teach me something there as you are a specialist of that beautiful adventure...)
Ooops! This is an anonymous forum

Last edited by Owain Glyndwr; 10th Oct 2013 at 09:25.
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Old 10th Oct 2013, 14:20
  #346 (permalink)  
 
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What's the link for the DC-9 manual with the limitations you mention?
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Old 10th Oct 2013, 14:26
  #347 (permalink)  
 
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flarepilot - regarding Hoot Gibson you said you remember what he said 32 yrs ago on 60 Minutes. CBS put out a report on the accident that took an entire hour. It wasn't 60 Minutes but a special report. Interviewed passengers, crew, etc. Is that the report you recall watching?
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Old 10th Oct 2013, 18:02
  #348 (permalink)  
 
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Originally Posted by bubbers44 View Post
Clandestino, does not Airbus teach pilots with loss of IAS that holding last attitude and power and getting out UAS checklist is the answer or do the French rely on Airbus automation?
Originally Posted by bubbers44 View Post
Of course if the auto pilot clicks off you need someone that knows how to hold an attitude and not just pull up.
Bubbers, you've answered your own question, because if the Airbus's systems detect a UAS condition, then the automation will automatically disengage. The old UAS procedure is available in the AF447 report, but the gist of it was to maintain a pitch of no more than 5 degrees and use appropriate power settings. I believe it has since been revised to read more simply, but in practice it's much the same.

What has changed for both Boeing and Airbus manuals since AF447 is the approach to training for stall handling - which was considered inadequate across the board as it relied purely on avoidance on approach to stall and had no advice or instruction for recovery when a stall developed (consequently meaning that a significant chunk of airline pilots had not practiced recovery from a stall since their PPL days).

misd-again: I think this is the report you're referring to:

Last edited by DozyWannabe; 10th Oct 2013 at 18:07.
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Old 10th Oct 2013, 19:37
  #349 (permalink)  
 
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Originally Posted by flarepilot
…also had the even greater pleasure of chatting with WEBB, who wrote, "FLY THE WING" and it is an equally fine book. One part of the book opened a new vista in windshear to me and I sought him out through the publisher.

He called me, chatted for 1 hour on the phone, and told me that I GOT IT! (ref : the art of flying) He then sent me some unpublished short stories which were great and a brand new autographed copy of his latest edition, also echoing the phone call sentiments.
I also had the pleasure of being able to call Jim Webb a good and personal friend of mine for quite some time when he was actively training and checking EAL DC-9 pilots in Miami and in Atlanta. He had a unique ability to be able to tell what a pilot was doing and, from that, developing his own way of dealing with any problems or misconceptions his student was displaying. I lost track of him starting around 1980-1981. Later, I did learn that he had retired from EAL but was not able to find him after that. I too have a signed copy of his “Fly the Wing” – and have very fond memories of evenings in the bar on 36th street – across from the EAL Training Facility in Miami.
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Old 10th Oct 2013, 20:55
  #350 (permalink)  
 
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Dozy - that's the report. Interviewed in Costa Rica. No mention of the rudder. Memory, especially 32 yrs after the fact, is tricky.
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Old 10th Oct 2013, 20:56
  #351 (permalink)  
 
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flare - perhaps the DC-9 speeds given are Va at that altitude?
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Old 11th Oct 2013, 18:43
  #352 (permalink)  

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Well, okay here we go.

I"ve flown it and offered what I remember from 30 years ago, you haven't flown it and offer what you heard from some guy.
I'll fess up and admit that I am that "some guy". I have flown, for a living not just a single flight, the Sabre 40/60, the Sabre 80 and the Sabre 65. I have have hand flown all of them from takeoff, climb, cruise at FL-450 and approach/landings. Of my 21,000 plus hours of flying time, over 3,000 of those hours are in Sabreliners. My last flight in a Sabre 40 was in 1984, last flight in a Sabre 65 was in 2005.

You are wrong about the aileron limitation of using more than one half aileron deflection above any altitude. The only aileron limitation of the Sabre 40/60/80 is:

From page 1-16 of aircraft limitations in the Flight Safety International Sabre 40/60 pilot training manual, last updated 1982, paragraph H, Maneuvering Limitations;

DO NOT USE MORE THAN ONE-HALF AILERON DEFLECTION ABOVE 225 KNOTS.

This limitation was not, repeat not, due to any structural concerns of the airframe. The FAA added this limitation due to the fear of the FAA that the rapid roll rate of the Sabreliner 40 was too rapid for the average civilian pilot at any airspeed above 225 knots*. The FAA decided that the risk of loss of control could result from a full aileron deflection at any speed above 225 knots, resulting in possible lost of control of the aircraft.

The Sabre 65 has no such restriction.

I will now state for the record; the Sabre 40/60/80/65 are very delightful to being hand flown, regardless of altitude (including FL-450), airspeed and in any configuration.

Only two other aircraft that I have flown that can equal that statement, any and all Falcons and the Lockheed Jetstar (-8 and the 731).

Therefore, in my opinion, a highly experienced opinion, any pilot that struggles to hand fly a Sabre 40, at any altitude or airspeed is either a very poor pilot, a very inexperienced pilot or has never done so.

Your choice to make.

Oh, edited to add.

The US Navy bought a number of Sabre 40s from the open market a few years ago. Then these 40s were flown to Perryville, MO to be completely overhauled and modified to Navy specs. One of the modification was the additions of small vortex generators on the wing in front of the ailerons, to increase the roll rate at full aileron deflection, at any speed under VNE, to increase the already impressive roll rate. These Sabre 40s are now T-39Ds.



* Which means that a FAA test pilot scared himself during the certification flights of the Sabre 40.

Last edited by con-pilot; 11th Oct 2013 at 18:55.
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Old 11th Oct 2013, 19:47
  #353 (permalink)  
 
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Hold up. The facts stated by Flarepilot were merely the opinion of an inexperienced pilot with a poor memory of what he is actually talking about?
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Old 11th Oct 2013, 19:51
  #354 (permalink)  

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When I flew it to FL450 without autopilot I had 10 hours in it and it was my first jet. and it took a little getting use to...but in a few minutes I had "THE HANG OF IT". SO excuse me again.
So your answer is a very inexperienced pilot . Fair enough, would have helped if you had said so at the start.

The Sabre 40 was the third aircraft I was typed in, the Jet Commander and Lear Jet (Lear 24) were the first two. After hand flying the Jet Commander at altitude, it was a pleasure hand flying the Sabre 40. The Lear 24 was not all that bad, but the 40 was much easier, nicer and more comfortable.

so some guy, did you happen to fly for HP?
No, the Sabre 40 and 65 was in corporate flight operations and the Sabre 80s were ex-FAA flight check aircraft that I flew while I was flying for the US Marshal Service.

BUT again it proves my point.
As for your point, I'm unsure of just what point you were attempting to prove. All I am responding to is your statement that flying the Sabre 40 was extremely difficult as compare to other aircraft that you have flown. Which indicated to me that you had experience hand flying other jet aircraft at that altitude. But now I understand that you did not have any previous experience hand flying other aircraft at that altitude, which makes what you posted very understandable.

Last edited by con-pilot; 11th Oct 2013 at 19:59.
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Old 11th Oct 2013, 20:18
  #355 (permalink)  
 
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Originally Posted by Clandestino
Quote:
Originally Posted by AirRabbit
To me, this is what I think that F/O was doing ... reacting with a skill set and doing so out of panic ... attempting to function without thinking logically or reasoning to any degree and was, instead, functioning out of an overwhelming feeling of anxiety and frantic agitation.

I'm afraid I agree with this one. Seemingly he firmly believed his actions were appropriate without stopping and checking whether they really were.
Well … when someone is operating out of panic, there is virtually no time where the person would “stop to check” anything. They are also not doing what they’re doing out of a belief that whatever it is would be proper or not. When someone is panicked they do whatever they do out fear and/or supremely heightened anxiety. There is no, or exceptionally little, conscious awareness of what they are doing. Their actions are formed from what some might call “a reservoir” of physical actions, the knowledge of which is buried in that person’s subconscious.

Someone on this forum has mentioned something called the “startle factor” – which has come to be something that psychologists (primarily experimental psychologists) have described as the “blinding” period of time that starts when something happens and continues until the time the participant recognizes that something has happened – and it is usually an extremely short period of time. However, when that participant does consciously recognize that something has happened, as far as I know, there is no standard of performance from that point forward. If the event is recognized, there may (or may not) be an action, or multiple actions, that could be satisfactorily taken to resolve the situation. The question is whether or not those actions would be effective only if taken in the proper sequence, and if so, will that person have the cognitive understanding of that requirement, and be able to logically take those steps, in that order? From here, comes the question of what to do … how to train … so that those who might be at risk for encountering unknown and unexpected events that could have tremendously serious consequences … could be expected to properly and successfully respond to the circumstance that generated the startle.

As someone whose career has been primarily devoted to education and training, I can say that, so far at least, I have seen nothing that equals the repetitive practice of doing something the right way, in the right sequence – over and over and over and over. The only variation that should be included (and it SHOULD be included) is the VARIABILITY of the initiating circumstances where each such variable initiation would result in the person having to respond with the appropriate steps, taken in whatever sequence that will get the situation to the desired level of completion. In aviation, I believe that this would be most logically accomplished by having pilots exposed to having their airplane experience “upset conditions” (including approaches to, and the development of, aerodynamic stalls) through as many variations as would be logically possible. The plan should be to have those pilots follow a logical process to maintain, or regain and then maintain, their airplane in a recognized and desired condition (i.e., position, attitude, altitude, airspeed, and configuration). To me, pilots practice doing this all the time when they are operating through the use of the primary and secondary controls to maintain (or regain and maintain) straight and level, un-accelerated flight. This training should focus on using all the available indications – mostly the flight instruments – ALL of the instruments – as well as the cues provided by sound, visual, and body position in space. And, when the pilot has developed a process that seems to be functional in all of the situations presented - the training should shift to achieving the same results but limiting the references to which the pilot may refer in taking the actions that he/she believes to be appropriate. And, in case you miss my meaning here, I'm talking about limiting the number of instrument references available. Of course, constant and vigilant observation, input, and correction (when necessary) remains a requirement for instructors during this training.

To my knowledge, this is the only way that pilots can be properly prepared - both mentally and physically - for something to occur for which there is no anticipation, and possibly no recognition. And it should be stressed that knowing "why" or "how we got to this position," is not as important as knowing "what to do now."

Last edited by AirRabbit; 11th Oct 2013 at 20:27.
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Old 11th Oct 2013, 20:21
  #356 (permalink)  
 
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Lord Spandax. Time will prove that flarepilot is our dear old SSG, aka teldorserious, who has never sat at the controls of any aircraft. Serial sciolist. Does spin a good yarn I must admit, which sucks people in. His claims are becoming more breathtaking with each new identity. Next we'll hear how he made ace status in the Vietnam war flying an F-4, or perhaps how he walked on the moon.

Congratulations ace on getting a fact partly correct. You've reached a high point in your contributions.
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Old 11th Oct 2013, 20:30
  #357 (permalink)  

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and at least I could, from memory, indicate at least one plane that had a limitation on control movement.
Yes, but in the case of the Sabre, except for the 65 which does not have that restriction, it was more about pilot capability rather than a structural issue.

Also, the 65 not having that restriction was the reason I had to look up the limitations. I could not say for sure that the 40 had any control movement restrictions or limitations.

Well that and being an old fart.

oh and con pilot...I seem to remember that at FL450 one of us had to be on oxygen all the time (it might be my memory fade or not...what do you remember?)

Actually above FL-400 or FL-410, depending on which pressure controller one had in the 40 and FL-410 for the 80 and 65, all occupants in the aircraft must wear an O2 mask, not just the pilots.

That's what the limitations are. I'm sure every Sabre operator complied with that.

Last edited by con-pilot; 11th Oct 2013 at 20:36.
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Old 11th Oct 2013, 20:54
  #358 (permalink)  
 
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Brian, I actually think that he's a recently banned poster called sevenstrokeroll. He has the same habit of single sentence paragraphs and starting each one without a capital letter, mostly. Oh, he used to get all shouty about his experience too.

SSR, 31 years ago I wasn't a professional pilot. I am now. I guess that answered your question.

my point was this: any plane with an unusual or unexpected characteristic should have a placard or a statement in the limitation section to warn the pilot
Thing is chap, the rudder doodah isn't a characteristic limited to just an A300 it's relative to ALL transport category aircraft and is, therefore, NOT unusual.
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Old 11th Oct 2013, 21:23
  #359 (permalink)  
 
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Something to do with drumming but he used to go on about the same thing as you. And flew the DC9, like you.


Most transports have ailerons and if you use too much you may roll upside down. Yet two transport cat planes have limitations published (maybe more)>
Did you really need a placard to tell you that?

Can't you just admit that the pilot actions were incorrect and were the cause of the rudder separation?

Oh, and why do you think that I'm a novice?!
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Old 11th Oct 2013, 21:32
  #360 (permalink)  
 
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Originally Posted by flarepilot
know what a 4 pt roll is and an 8 point roll, even a 16, but what is a 7 stroke roll?
Well, I was always under the impression that a “7 stroke roll” was a roll completed by a pilot with 7 passengers aboard, where all 7 suffered an incapacitating stroke when they thought they were going to die. The only thing I can’t remember is how many of the 7 actually died from the experience ... or was that a story told by old heads to younger wet-behind-ears novices?

Oh … a quick supplement … I find it curious that anyone would think that a placard, about anything, mounted anywhere on the airplane, would prevent someone from doing anything after that person panicked and responded out of that mentally debilitating state.

Last edited by AirRabbit; 11th Oct 2013 at 21:39.
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