Thursday 26 April 2018

KNOW WHEN TO FOLD EM: HOW TO AVOID TUNNEL VISION IN THE COCKPIT

Acknowledgements: AIR FACTS (John Zimmerman)

(Ed. Note: Yet another great article from AIR FACTS using actual examples to help us to develop our own personal Safety Awareness - Cheers John!)

“Have you ever noticed that you become less and less flexibleas a flight goes on? Decisions that once would have been easy and stress-free become fraught when you’re close to home. It’s a natural human instinct, but it’s one pilots need to aggressively fight.

I was aware of this trap while planning a recent cross-country flight when the weather was decidedly marginal. Sitting at home, I was considering whether to cancel the flight entirely – it wasn’t unsafe to fly, but it was an ugly day, with scattered thunderstorms, potential in-flight icing, and gusty winds. After a closer look at the radar and some fresh METARs, I decided to drive to the airport. 

Once I was at the hangar, though, I almost felt locked into taking off. I was emotionally invested in my decision, and didn’t want to look unsure or timid, especially after my passengers arrived. Could I really cancel now?I could, but had to admit that it was becoming harder by the minute. Sensing a potential trap, I excused myself from the passengers to review the plan and the trip. I asked myself what I would tell a friend in the same situation who called me for advice? On the pro side, weather conditions were above IFR minimums by a comfortable margin, I was proficient in the airplane, and we would be flying towards improving weather. So I decided it was a challenging but completely safe flight, then walked back to the airplane and we blasted off. Our flight was uneventful and surprisingly comfortable, so I felt confident that I had made a good decision, but obviously some outside pressurehad crept into the process.

The same thing can happen in the air – the closer you get to your destination, the more your optionsseem to narrow. Right after take-off you might consider turning around if things look bad, and en-route you might tolerate a 100-mile deviation around weather to be sure. But within 20 miles of the airport, it’s amazing how tunnel vision can take over.

Identifying the problem
The formal term for this trap is “plan continuation bias,” a fancy-sounding phrase that nevertheless describes the problem pretty well: the more time you invest in a plan, the less likely you are to change it. Tell-tale signs that this bias is at work include statements like, “I can salvage this,” or “We’ve come this far, we can’t turn back now”. It shows up in all kinds of accidents, including fuel exhaustion and VFR-into-IMC scenarios.

One example of this bias at work involved an American Airlines MD-82 which crashed at Little Rock Airport in 1999. It was late at night and the weather was bad, with thunderstorms all around. The pilots were tired and this was the last leg of the day. As you might expect, this crew wanted to get on the ground soon, and they were very close to landing – perfect setup for plan continuation bias. So they continued their approach, even as a thunderstorm parked itself over the airport. The result was a runway overrun that killed the captain and 10 passengers.

You might think this is just another way of describing “get-there-itis,” but there’s more to it than that. A huge percentage of general aviation accidents occur during approach or landing, including a stall/spin on final, runway overruns, and ground loops – often in good weather with perfectly functioning airplanes. In many of these situations, the pilot ignores the urge to go around and tries to make the airplane land when it simply doesn’t want to, reasoning that abandoning the approach would risk public embarrassment!

A Lear-Jet accident at Teterboroshows how strong the urge is to continue an approach even when things start to go wrong. The airplane, with only two pilots on board, was flying the circling approach to runway 01, a common but demanding visual approach. Winds were gusty, but more importantly the approach was never stabilised. The co-pilot, who was flying, did not start the turn for runway 01 until the airplane was less than a mile from the end of the runway. From this point, it was almost impossible to safely land the airplane. Anyone who has ever flown to the New York area has to admit that a go around at TEB is a big deal. Of course an accident is even a bigger deal, but if ever there were a setup for plan continuation bias, this was it.

How to prevent it
Eliminating this bias isn’t possible, but there are number of strategies for minimising the threat: 
·      First, force yourself to stop periodically during your pre-flight and in-flight decision making, so you can evaluate the situation in an honest way – perhaps before engine start or before beginning your descent from the final approach fix. 
·       Is the flight really progressing according to your plan? 
·       Is your decision-making being affected by how far along the flight is? 
·       How would this read in an NTSB report?
·       The best question to ask is, “What alternatives have I not even considered?” This was the mistake I made on my flight; I was locked into a binary “go/no-go” decision, when there were other options to consider, including delaying a few hours or taking a different route. 
·      Second, it’s important to be disciplined about the regulations, and your own personal minimums. If your minimum is one hour of fuel in the tanks at landing, then you don’t go below that number under any circumstances. It does not matter that you have restless passengers on board, it’s getting late, or anything else! 

This is also where the concept of a stabilised approach comes in. You don’t have to fly a 20-mile final at Vref (unless you want the tower to yell at you), but by 500 feet AGL you should be on speed and on glide path, ready to land. If you’re not, it’s an automatic go around.

In the MD-82 accident, the pilots ignored two automatic go around cues: 
·      they lost sight of the runway 
·      the crosswind exceeded company SOPs 
Either oneof these should have caused an immediate abort, with no discussion or debate. 

That’s the critical point with minimums: the decisions have to be automatic. If you leave yourself much wiggle room, the human brain will go to great lengths to justify a deviation, “just this one time”.

Another important consideration is how you manage your workload, since tunnel vision often takes hold when you are distracted or overworked. 

In the Lear-Jet incident, the crew ended up reacting to events instead of staying ahead of the airplane. Managing workload might even require a delay vector from ATC or a turn in a hold, just to give yourself time to think.

Finally, some pilots like to plan an alternative whenever an important trip is on the calendar. This could mean packing an overnight bag (even for day trips), so there’s a little less pressure to continue when conditions change. Or it might mean buying a backup airline ticket for the return leg of a long trip. The right answer will depend on the type of flying you do, but the important point is to build some tools that help you make a more rational decision. Never sacrifice flexibility because you’re tired or rushed. And remember, it’s never too late to turn around or go around”.


FLY SAFE!

LOSS OF DIRECTIONAL CONTROL ON RUNWAY

Acknowledgements: Thomas P. Turner (Mastery Flight Training Inc.)

(Ed. Note: The following excerpt is taken from Tom’s weekly lesson, received today – thanks Tom!)

Just since last week’s lessonsin the FAA Preliminary Accident Reports:
·    A Honda Jet “veered off the runway through grass while landing….”
·     A Taylor-Craft “landed and was blown off the runway….”
·     A Piper Cherokee “veered off the runway into the grass….”
·     A Piper Seneca “veered off the runway into the grass….”
·     A Beech Super King Air blew a “tire on landing, aircraft then veered off the runway….”
·     A Piper Seneca “veered off the side of the runway during landing….”
·     A Cessna 172 “was cleared for takeoff, veered left into the grass….”
·     A Republic Sea-Bee “went off the runway into a ditch….”
·     An Evangel Angel tricycle-gear twin “ground looped upon landing and struck runway lights….”
·     A Taylor-Craft “veered off the runway and flipped over….”
·     A Kolb Mark III “on landing veered off the right side of the runway into the grass….”
·     A Gippsland GA8 “blew a tire on landing and veered off the side of the runway….”
·     A Piper Cherokee “struck a snow bank on landing and veered off the runway….”
·     A Piper Cherokee “damaged a runway light” while landing.
·     A Bellanca Citabria “went off the runway into a lake and submerged in water….”
·     A Piper Pawnee “lost control on departure with a glider attached, went off the side of the runway….”

This tells us two things: 
(1) Someone in the FAA Safety Centre really likes the word “veer”!
(2) We’re having trouble maintaining runway alignment and aircraft control, especially during landing.

That’s 
16 Loss of Directional Control on Runway(LODC-R) events reported since last Wednesday. Take the two blown tires off the list (we’ll assume the tires blew and caused the loss of directional control, not the other way around), and there are still 14 events in the last eight days of reports. It seems as though this is common this time of year, as many Northern Hemisphere pilots are getting back into flying after a long winter at the same time the winds tend to increase with the change in seasons. 

In the eyes of our passengers the 
measure of a pilot seems to be how smoothly he or she lands the airplane. They feel a good landing means a good pilot, but a firm or bounced touchdown negates everything the pilot did to that point! Somewhere between the two extremes (that the landing needs to be glassy smooth or it may destroy the airplane, but it’s okay as long as no one is crippled!) lies the reality: we need to land with a level of aircraft command.

How do we avoidloss of control on the runway (LODC-R) or runway overruns? Every situation is different, but you’ll improve your precision and reduce your chances of joining the list of “on landing….” by doing the following:
·     Taxi with the nosewheel on the centre-line. This reinforces your perception of deviationsfrom runway directional control. Discipline here will pay dividends when you need to be making instinctive control inputs during take-off and landing.
·    Use the correct crosswind controls during ground operationsThis makes instinctive your input of proper corrections during crosswind landings… even when winds are less than when you think you need the crosswind controls.
·    Fly at the correct speeds. Trying to land too fast - a common mistake- makes it harder to land accurately in the touchdown zone, thus making a runway overrun or the need to apply heavy braking (leading to nosing over) more likely. Even in strong gusts you don’t need to add that much speed; the convention is to add one-half the gust value. The result is much less added speed than you might think. For example:
·     if landing a Cessna 172 in winds at 15 gusting to 22 knots, the gust factor is seven (22-15=7) and half that is three and a half. So your final approach speed increases from, say, 65 knots to 69 knots… not 75 knots, or 82 knots, or 90 knots, or some other amount that makes it more likely you’ll land long or run off the end of the runway. 
·     In a mid-weight Beech 58 Baron landing in that same gust factor increases over the threshold speed from 91 to 95 knots. 
·     In a Citation the increase is almost negligible as a percentage of VREF(final approach reference) speed.
·     If you receive Pilot Reports of wind shear with airspeed fluctuations on final approach (e.g., “airspeed varies +15 knots”) you might add as much as that variation amount to your final approach speed, knowing you still have to dissipate it in the final moments before touchdownIf that speed adjustment is more than about 20% of your airplane’s final approach speed you probably need to land somewhere else!. If the report comes from an aircraft larger than the one you are flying treat wind shear PIREPs the same as you’d treat a turbulence or icing PIREP from a larger aircraft—expect that the indications will be worse for you.  
·    To be prepared for those speeds, practice and retain proficiency and comfort flying at low speeds and high angles of attack. Practice “slow flight” or, as we used to call it “flight at minimum controllable airspeed” so you not only apply controls in the proper direction, you also apply them in the correct amount… without having to think about it.
·    Be established on speedinconfigurationonglidepath to your planned touchdown zone, and inalignment with the runway and the runway centre-line between your main wheels within about 400 feet of the ground, or certainly before you cross the runway threshold… or go around without question or delay.
·    Fly enough to know your capabilities, and your limitations. In most LODC-R mishaps the crosswind component is far below the airplane’s maximum demonstrated amount. In most LODC-R events the crosswind component is less than 10 knotsIn almost all cases it’s pilot issue, not an airplane issue. If you’ve not flown crosswinds recently, reduce the amount of crosswind you’re willing to accept. 
·     Discipline yourself towardexcellenceBack it up with demonstrated proficiency. And use good judgment to avoid situations you knoware beyond your current capability.

Although it doesn’t have the appeal (if that’s the right word) of thunderstorms or ice or low clouds and fog when discussion aviation weather hazards, the wind, especially wind during take-off and landing, is the single largest weather hazard to non-transport category airplanes, according to the accident record.

Most pilot training textshome in on the stick-and-rudder skills needed to maintain runway alignment in a crosswind. That’s absolutely essential, and crosswind control should be at the centre of all your recurrent training. But the industry is remiss in omitting the 
single biggest factorin the success of a crosswind landing - the decision whether or not to try it in the first place.

Take-offs are optional. Landings are notHowever, landing at any one location, or on a specific runway, is optional. Make a conscious decision to accept or rejecta landing by figuring the crosswind component before accepting an approach or entering the pattern/circuit. Most LODC (Loss of Directional Control) on landing events occur, in fact, with reported surface winds reported below 10 knots

So why do we lose directional control in such relatively low surface winds? I suspect that:
·    We’re not as current in crosswind landings as we think we are.
·    It doesn’t take much changefor a crosswind to swing around and include a tailwind component, which is even more destabilising to many airplanes.
·    Some pilots may be too rushedto fly to a landing into the wind when their route of flight is nearly straight in to a more convenient, if not wind-aligned, runway.
·    Others may not be assertive or confident enoughto change runways when ATC assigns a runway the pilot would not chose on his/her own.
·    Flight instructors may notbe emphasising good crosswind technique, including “flying” the airplane all the way to the completion of the landing roll.
·    Many pilots may not botherto consider the effect of wind as part of their arrival briefing.

How can we address these possibilities? 
·     Practice 
·     Realisticself-evaluation 
·     Renewed emphasis on proper techniquein flight instruction for pilots at all levels, 
·     Having the confidence to refusea runway when the winds do not favour its use…even if others are using it or if initially assigned by ATC. 

This means consciously estimating the crosswind as part of your arrival self-brief, and developing the willingness to request another runway or even fly to a more favourable airport”. 


FLY SAFE!