Originally Posted by JammedStab
No, you are to believe that Boeing says that this is a procedure which I repeated. Nothing more and nothing less.
Quote:
Originally Posted by AirRabbit
Just so I understand … you are saying (are you not) that Boeing has developed a procedure which pilots are perfectly welcome to use, and using this procedure will automatically recover the airplane from a windshear encounter, and, of course, you are aware that any procedure developed by Boeing, recommended by Boeing, and found in the Boeing operations manual, if used exactly as Boeing has recommended, will put Boeing directly in the sights of litigation should anything catastrophic occur … and Boeing is accepting this situation for windshear encounters. I just want to understand your comment.
I'm sure if you re-read it you will understand it. It is a procedure which is what it is. if you don't like the procedure, and you may very well have good reasons for not liking it, feel free to let us know. That is what the forum is for and any professional input from you is quite welcome.
Hi J/S … I took your recommendation to heart and found what I think is the reference you were citing … but, what I found was an operating description of the Automatic Flight Director System (AFDS) and not a “procedure.” Here is what I found by searching Boeing Flight Manuals for Automatic Windshear Recovery:
The AFDS provides windshear recovery guidance by means of the normal go–around pitch and roll modes. With go–around armed, pushing a TO/GA switch commands a pitch–up of 15 degrees or slightly below the pitch limit, whichever is lower. As rate of climb increases from 600 to 1200 feet per minute (0 to 600 feet per minute with engine out), AFDS gradually transitions from pitch to airspeed control. The target airspeed is IAS/MACH window airspeed or current airspeed, whichever is greater when TO/GA is activated. If current airspeed remains above the selected speed for 5 seconds, the selected airspeed is reset to current airspeed, (to a maximum of the IAS/MACH window speed plus 25 knots). When the autopilot is not engaged when go–around is initiated, the pilot must fly the windshear recovery following the flight director commands. If the autothrottle is not armed, the thrust levers must be advanced manually.
As I read this, it is not evident to me that this should be understood to be a “procedure” that is to be followed, but rather, to me this is a description of how the various systems installed on the airplane actually provide information visually to the flight crew, and describes to the flight crew what the visual displays represent – together with a description of the various parameters that are involved. Additionally, I am perfectly comfortable with the fact that Boeing is providing all the information they are capable of providing … and I’m sure they offer this description because under the greater percentages of time when a situation occurs similar to one that would suggest a pilot might use these systems as described here, this description is very likely exactly what the pilots will see. Additionally, I’m quite sure that Boeing is not advocating that any pilot would blindly follow any so-called “procedure” if the information being presented is suspected of providing questionable information.
Having said that, this description does not indicate, at least in this section of the manual, what the flight crew should do if the conditional parameters described here are not met. For example … the paragraph describes that “if go-around is armed, pushing a TO/GA switch commands a pitch-up of 15 degrees or slightly below the pitch limit, whichever is lower” … and that “…as the rate of climb increases from 600 to 1200 fpm, the AFDS gradually transition from pitch to airspeed control…” I’m confident that this is exactly what the systems involved will do. However, it does not indicate what happens or what should be done if the rate of climb does not increase … or if it begins to decrease. It also describes what the pilot must do if the autothrottle is not armed/engaged ... “the throttles must be advanced manually” … and if the autopilot is not engaged when the go-around is initiated … “the pilot must fly the windshear recovery following the flight director commands.” But, as I’ve said above, what happens if the flight director commands are insufficient or you need something to be done a lot more “robustly” than what the automatic systems are providing … what then? Of course, the answer is FLY the AIRPLANE.
What I’m saying is that this paragraph describes how the systems are designed to function – given a very specific set of circumstances – with the anticipation that all of the parameters will be realized as is presumed in the paragraph’s content.
OK. Out of concern for the well-being of those of you who absolutely abhor long posts … stop reading … and those of you who have concerns about or question my professional history … stop reading ... and anyone else who is not interested in what I have to say on the subject of training ... stop reading. Continue at your own risk.
Quite some time ago, I was involved in a rather major effort to determine a satisfactory pilot reaction to an inadvertent windshear encounter. This was the new, “hot button” issue at that time, not long after the windshear accidents at New Orleans and JFK. A fairly sizeable group assembled at the Boeing facilities in Seattle where Boeing had programmed into one of their B737 systems trainers (not a full flight simulator – but it had pretty good aero-programming) representative windshear parameters, closely representing a combination of those two accident profiles – but with the ability to alter some of the severity of the actual shear. Each of us was given several opportunities to conduct a takeoff and experience the “fun.” They could (and did) adjust the gross weights, and used varying flap settings for takeoff – and inserted various combinations of down-drafts, nose-to-tail wind shifts, etc. … some of which were designed to be survivable with application of the proper procedures and some were designed to result in a crash, regardless of the techniques and control applications used. I took my turn … and I had the opportunity to demonstrate my “stick-n-rudder” skills, in a relatively heavy weight B737 TO with a takeoff flap setting of “5,” the programming used called for a relatively significant nose-to-tail shear just after lift-off. I fought valiantly, but to no avail … and crashed … just as it was designed to do. But there were 3 of us who had previously discussed alternative sets of responses … and I asked to repeat the same circumstance. We did just that … set everything up exactly as the first attempt. However, after encountering the shear, after advancing the throttles to the firewall, after getting well into the stick-shaker, I called for “Flaps 15” – and when the Boeing instructor in the other seat hesitated … I grabbed the flap lever and moved it to the “15” detent. We did not crash. And the Boeing personnel were highly “insulted” that I had the temerity to do something other than what they had designed as “the” procedure … saying that adding flaps also increased drag – and THAT was something that simply should not be done – as it would result in catastrophic results! When the group, as a whole, asked if the trainer was accurate with respect to its aerodynamic responses, they indicated that it certainly was. Our group acknowledged that adding additional flaps would very likely increase drag, but as long as the airspeed was sufficiently high, lift would also be increased – and to a much larger percent than additional drag would be generated. Of course, we all recognized the pros and cons of both sides of this particular circumstance … but the “procedure” to make “no configuration” changes, while perfectly logical in some circumstances, was found to be not so logical in others. Of course, we were not suggesting that a flight crew can or should indiscriminately raise or lower flaps or landing gear. But, after some very lengthy discussions, even Boeing acknowledged that in some circumstances, adding additional lift capability, even at the cost of some additional aerodynamic drag, could mean the difference between an accident and a drinking-story.
And … before any of my regular detractors who have ignored my suggestion earlier to “stop reading” begin to throw barbs in my direction, alleging that I am, yet again, touting my experience, or blowing my own horn … let me say that anyone of the 3 of us that had agreed to attempt this particular example could have been at the controls at the time – and, in fact, it was both of the other guys who did most of the arguing that took place at the trainer that day.
My point is that knowing what the airplane is capable of doing, and being confident in what, when, where, why, and how you desire to manipulate the various parameters available to you as the pilot flying any particular airplane – can be, and sometimes IS, all the difference between the same two potential outcomes – accident or war-story. This is only one of the reasons that I have continually advocated that pilots should learn (and practice to the greatest extent possible) all they can about their airplane – the training that is conducted should provide a wide-range of familiarity with the airplane responses and resulting capabilities. In fact, I would not argue if the regulator was to mandate such extensive training, at least initially, and to whatever extent is thought appropriate on a recurring basis. Things like recoveries from an aerodynamic stall … slow flight demonstrations while maintaining level flight, turns, climbs and descents – using the stick shaker or other stall warning as the reference cue – all conducted at very light, intermediate, and very heavy gross weights and at various airplane configurations of both flap and gear extension … recoveries from a bounced landing … go-arounds from rejected landings … accelerate – stop / accelerate – go distances … balanced field … climb performance (segmented climb, engine malfunctions) … the automation policy of the company including written operating procedures for selecting and deselecting appropriate levels of automation, and CAT II and CAT III approaches when authorized … ice protection (anti-ice and de-ice) pitot-static system(s), windshield, wing and tail surfaces … and, as you might expect … the list could go on and on. I fully recognize that working for a company requires each of us to do what we're contracted to do ... but I also believe that we're not merely programmable beings ... and we have a duty to do all we can to protect and provide appropriate service for our passengers - the best way I know how to do that is to ensure I know and practice all I can about my airplane and how to best react to whatever circumstance occurs - whether it results from my actions or actions of others, including "mother nature." How we get to that point is the issue ... it has to be by willingness on our parts (including our bosses) or by direction of the regulator - and likely the best way would be a combination of the two.
Sorry ‘bout the “rambling” – but, I did warn you.