nmflyguy wrote:.......This notion of elevated sensitivity is not unlike what most wild animals exhibit whenever they sense risk, or vulnerability, in the wild. .......

It's referred to as "spider sense".

GlassPilot wrote:We did fly the profile (mostly). We stayed configured until well clear at least. It was a clear day, albeit gusty so micro burst was out. We just got into a "backward gust". Like I said, I left us configured while he held pitch until we accelerated out of it. By the end of the runway we were well on our way upward on speed and climbing normal. My plane has a stall computer but does not have the eyebrows.

I don't think we're from the same airline. I'm former ACA / Independence Air.

You can't be all bad then! Unless you were on the dark side the whole time. I was ACA/Indy too. Did all my time on the Delta Connection side in the Dojet. Welcome. This is a great group of guys here.

Lol, if by "dark side" you mean UEX, then I'm afraid I'm guilty. ORD based the whole time till booted, kicking and screaming, to IAD.

Cheers though. ACA/Indy were a great bunch!

Yup! I was referring to UEX , but I guess the real dark side was Skeen and friends. Good group indeed. A whole bunch of us ended up over hear at Jetblue. It is good to still see/work with the same good people. Where did you land? Living in Boise so that's not bad!

GlassPilot wrote:I've never liked blanket statements like, "when things get ugly turn the automation on" or, "when things get ugly turn it off".

Automation is a tool. A good pilot uses all his tools in the appropriate manner at the appropriate time.

As to shear, just yesterday I was taking off from KAPA and we lost 20 kits just after rotation. My FO called for gear up and was a tad annoyed I left them right where they were during the shear. I explained latter I thought it'd be nice to have 'em down in case our flight was going to be real short.


P.S. This is my first post, I've been reading the forum for just a couple of days and am very impressed with all of your posts. This place has a great vibe I've not seen elsewhere!

Fly safe,

GP

Europe Regulators To Curb Autopilots

By ANDY PASZTOR

(WSJ) European air-safety regulators, stepping up warnings about excessive dependence on cockpit automation, have told pilots of two widely used Airbus jetliner models to avoid routinely using their autopilots in certain emergencies.

The directive issued last week by the European Aviation Safety Agency, or EASA, specifically covers emergency procedures for more than 1,000 Airbus A330 and A340 jets in the event of major airspeed-sensor malfunctions. More than two-thirds of the two-engine, wide-body planes are flown by European or Asian airlines.

More broadly, the move reflects growing concerns by international safety experts about the hazards of undue reliance by pilots on on-board automated systems, following a spate of incidents pointing to pilot mistakes and confusion stemming from improper use of automated safety aids.

Safety officials believe many pilots flying a wide range of jets-across the U.S. as well as other regions-may need additional training to cope effectively with emergencies when autopilots or automated thrust-control systems are unavailable or can't be trusted.

"Given the increasing dependence on automation" in the latest generation of jetliners, according to Deborah Hersman, chairman of the U.S. National Transportation Safety Board, "you've got to have pilots who are prepared for all scenarios, especially those in which they have a lack of information" from typical flight-management sources.

If two of the three external-airspeed indicators on the Airbus models singled out by last week's directive provide unreliable readings, autopilots and automated engine settings are designed to instantly disconnect. But instead of routinely re-engaging both at the first sign of trouble to try to control the aircraft, EASA now requires pilots to wait at least 30 seconds to determine if reliable information is flowing into the automated systems.EASA's directive also follows the recent release of a long-awaited U.S. air-safety study emphasizing that commercial pilots tend to abdicate too much responsibility to on-board computers, partly because most current training programs emphasize that automated systems generally are more adept at handling in-flight emergencies.

Crews also must perform various other checks to ensure that the automated systems will issue appropriate orders once they are switched back on.

When speed sensors feed unreliable data to flight-management computers, EASA said the result can be autopilots issuing abrupt and "inappropriate" climb or descend commands, which may "constitute an unsafe conditions." Regulators patterned the directive after a separate safety warning issued by manufacturer Airbus, a unit of European Aeronautic Defence & Space Co.

The move comes after a series of dangerous airspeed-measurement failures and unpredictable or dangerous autopilot commands on Airbus A330s in recent years. The sequence of events that led to the June 2009 crash of an Air France Airbus A330 flying to Paris from Rio de Janeiro apparently started with unreliable airspeed indications and autopilot difficulties. No formal cause has been determined for the crash, which killed 228 people

Interesting article. Here is another one for you. Maybe Barry is lurking on this forum and got the idea for his article? Basically what he is writing about is the groundspeed mini that I talked about earlier.

Proficient Pilot: Maintain Thy Groundspeed.

The other day I read an article by Ross Detwiler in the October 2010 edition of Business & Commercial Aviation. The article conveyed a concept so simple in principle yet so profound in potential benefit that I immediately decided (at the risk of appearing plagiaristic) to pass it along to readers of this column. The concept has to do with the manner in which a pilot prepares to combat a suspected or reported wind shear on short final approach, especially the decreasing-headwind type of shear that can quickly rob a pilot of critical airspeed.

Most pilots attempt to counter a conventional wind shear (not one generated by a microburst) by simply increasing airspeed. But by what amount should airspeed be increased? As Detwiler points out in his article, pilots can increase their normal approach speed by half of the gust factor, all of it, the total headwind component, or something else. Instead, he suggests a procedure taught to U.S. Air Force pilots. This procedure instructs pilots suspecting a wind-shear encounter on short final to maintain a groundspeed equal to the airspeed normally used on final approach.

What? Maintain groundspeed and not airspeed? This might initially sound like heresy, but let’s back up for a minute and review what happens during a wind-shear encounter. What at first blush sounds absurd is both logical and reasonable.

Assume that you are flying an airplane with a normal approach speed of 80 knots, and you note from your GPS that groundspeed is 50 knots, the result of a 30-knot headwind component. The tower clears you to land and adds that previous aircraft have reported a 15-knot airspeed loss on short final because of wind shear, the result of a sudden change in the direction and/or speed of the headwind component. What needs to be emphasized is that although flying through the shear obviously results in a 15-knot loss of airspeed, groundspeed will remain essentially the same because of aircraft inertia. In this case, airspeed will decrease from 80 to 65 knots during the wind shear but groundspeed will remain at 50 knots.

The U.S. Air Force teaches pilots anticipating the possibility of a wind shear on short final approach to increase groundspeed so that it is the same as the airspeed normally used on final approach. This means that in the example cited above, the pilot would increase airspeed so that groundspeed is 80 knots. Airspeed before the wind-shear encounter, therefore, would be 110 knots. Now assume the worst-case scenario: The wind shear is of such a magnitude that the entire headwind component disappears, the maximum possible wind shear. Groundspeed would remain the same after such an encounter, 80 knots in this case. The minimum airspeed that would result also is 80 knots, which is exactly the same as the indicated airspeed normally used on short final.

The pilot could accomplish the same thing by increasing airspeed by an amount equal to the headwind component that exists prior to the wind shear. The problem is that pilots often don’t know the headwind component when crossing the outer marker, for example. The easiest way to accomplish the same thing is to simply increase groundspeed to match the desired and normal final-approach airspeed. In this manner, it would be impossible for airspeed to decrease below that which is normally desired (even if the wind shear consisted of a sudden loss of the entire headwind component).

In this manner, a pilot encountering a substantial wind shear on short final is prepared for it. All he would have to do upon experiencing a sudden loss of airspeed would be to arrest the sink rate by raising the nose and adding a little power, something that would be relatively easy to do because of the airspeed surplus available prior to the encounter.

One concern might be excess airspeed when crossing the runway threshold. Won’t this increase the runway distance required for landing? No. It is touchdown groundspeed, not airspeed, that determines landing distance. So even though airspeed might be higher than normal, groundspeed will be same as when crossing the boundary using a normal approach airspeed under no-wind conditions. This would be true even if the pilot did not encounter the anticipated wind shear and landed with all of the airspeed added in anticipation of a wind shear.

There is one problem to be considered when crossing the threshold with excess airspeed and that is the relatively nose-low attitude of the aircraft required to fly a faster-than-normal approach. This can be handled in one of two ways. The first is to simply enter a prolonged flare to dissipate excess airspeed (provided that there is sufficient runway to do so safely). The other is to gently “roll” the mains onto the runway and be aware that the nosewheel might be touching down at the same time (because of the nose-low attitude). Caution is required here to avoid wheelbarrowing down the runway. This can be avoided by holding back pressure on the control wheel after touchdown and braking very gently during the initial phase of the rollout.

On the other hand, if a wind shear is encountered as anticipated, the pilot will not have such excessive airspeed, and he will have survived the experience to fly another day.

Whether you adopt this procedure or not is, of course, up to you. It is presented here only for your consideration.




Visit the author’s website. Barry Schiff has conducted flight safety seminars in 14 countries.

Interesting read, GrassStrip.........

So, can you use your ground speed off of your GPS?

So, in other words if the pilot ahead of you reports losing 15 knots on short final you can increase your airspeed 15 knots. Which is all fine and dandy until the micro-burst dissipates and you find yourself with 15 knots too much speed. Hopefully not high as well as hot and on a short runway. Using the groundspeed method is fine if you have some sort of way to quickly read GS while on short final. I have heard that GPS, or DME, groundspeed does not react quickly enough but if you have an INS in your cub that will work a lot better. It just so happens that we may be upgrading our cockpit if we don't get a newer airplane and will have 2 INSs for sale. They only weigh 50 pounds. each.
Most airlines now have windshear detection equipment and have written their ops specs making a go around mandatory if it goes off.

I've never seen much if any lag in groundspeed and the 496, 430, and other Garmin I use are easily referenced. However, I'm sure that there are those that would be harder to reference.

I based that on what I heard, that is that the windshear alert systems base their information on Inertial inputs instead of GPS or DME because while GPS is pretty quick it still lags by a second or so which in the windshear world is a lifetime. The other reason is that Inertial will sense a change in crosswind while your groundspeed may not change all that much.

Sorry. I missed that you were talking about using GPS for windshear detection. I looked at the A320 and the IRs are one of many things the Flight Augmentaion Computer looks at to detect windshear. I tried to copy over the info but it won't allow me to copy it.

Anyway, for our purposes, Barry was simply saying to use the GPS to maintain the same groundspeed in the event that you encounter the shear (essentially this preserves the aircrafts energy). His second to last paragraph mentions the one draw back if you end up with excessive airspeed...something you'd have to take into consideration. In the A320, if the headwind goes away, the computer brings the bug back to a normal approach speed and adjusts power accordingly. Kind of cool.

Hope you get a good cockpit upgrade!