Wednesday, 26 October 2016
Acknowledgements: GASCO/Nigel Everett
Landing accidents form the greatest proportion of total accidents reported by GA aircraft, and we may be sure that there are also many other landings which only just escape injury or damage and thus are not reported as accidents.
The good news is that they are seldom fatal, and so the usual outcome is damage to aircraft but little personal injury, although as a result the cost of higher insurance premiums can be considerable, as can the loss of self-regard and confidence on the part of those involved.
Employing the three disciplines described below will greatly reduce the likelihood of a landing accident if done right, or greatly increase it if done wrong.
1. Established on finals
In the airline world there is a minimum height requirement for becoming fully-established on final approach, and we GA pilots should adopt the same discipline voluntarily. Decide upon a minimum fully-established height, recommended by Jeremy Pratt to be 300 ft. but taking account of your own personal parameters in terms of experience and confidence, and ensure that you have done everything needed to prepare for landing by the time you attain that height. After which do not attempt to correct anything which is not as it ought to be for maintaining the fully-established condition – airspeed, trim, configuration, final checks, ATC clearance if appropriate etc. If after that point any adjustment is needed GO AROUND! This will greatly reduce your chances of a landing accident.
2. Approach speed
The accepted approach speed for a powered light aircraft is 133% of stall speed in landing configuration and at current weight, though some prefer 125% as it gives a shorter float and landing run - but also of course less margin for error! In windy conditions you should add a “gust factor” equating to 50% of the difference between current wind strength and gust speed. High speed on landing is likely to result from a high speed approach.
If flying a tail-dragger a high speed landing is rarer as a high-speed approach will not achieve an acceptable 3-point touchdown. The problem is more acute with a tricycle geared aircraft, as the pilot can “get away with” a 3-pointer as long as the nose-wheel doesn’t make contact significantly ahead of the main wheels. Thus we frequently see a nose-wheel aircraft arriving too fast and touching down flat after very little holding off, which means that the aircraft is still partially flying. Many landing accident reports reveal problems in the roll-out rather than the touchdown, because the aircraft landed whilst flying so that the brakes and nose-wheel did not function as expected. This is generally avoidable if the pilot does not allow the aircraft to touch down until it has run out of flying speed.
Studies have shown that the incidence of accident is inversely proportional to the amount of flap deployed. More flap = fewer accidents so the advice is to use more to stay safer, because you will achieve a slower touchdown with less reaction to gusting, and a more “draggy” and stable aircraft. The transition from airborne to ground borne is risk-inherent, and the use of flaps helps to minimise the duration of the landing phase and to improve control during it.
Wednesday, 19 October 2016
Acknowledgements: AIR FACTS/Steve Thompson
Most will agree that on a long VFR flight, there are stretches of time when your mind can wander. Other than doing the usual drills, here are the top activities for putting that time to good use:
10. Play with the ADF. If you’re blessed with older avionics, chances are good that you have an ADF in your panel. While the antiquated Automatic Direction Finder is intended to provide navigation based on the location of an AM radio station, it also allows you to tune into the AM broadcast band, where you can find some interesting programs to listen to; and by watching the ADF needle and confirming the station on your chart, you’ll learn more about how to use your ADF.
9. Submit a PIREP. Regardless of weather conditions, even if it’s clear and smooth air, reach out to Flight Service and give them a PIREP. You’ll become familiar with the format and exchange, and it’ll be useful information for the next pilot who comes along. If you have forgotten the standard dialog, just ask Flight Service to help you through the process and they’ll be glad to do so.
8. Create an efficient scan of critical instruments. If you’ve not already developed an optimal scan pattern, then here’s your opportunity to create one – this might be a left to right, top to bottom scan, or another pattern depending on your panel layout. Then, use your scan regularly… someday it might give you a warning of impending failure and you’ll be glad you caught it early.
7. Play the Alphabet Game. If you’re flying with your kids, then play the Alphabet Game with tail number suffixes heard on the radio. It’s a way for young pilots-to-be to learn the Phonetic Alphabet, and it encourages them to listen what’s going on with ARTCC.
6. Refresh your VOR skills. VORs are slowly being phased out, but are still valid means of determining your location should alternatives be unavailable. If you have a NAV radio, tune to the nearest VOR and confirm the CDI (Course Deviation Indicator) indication agrees with other means of navigation. If you’ve got two CDI instruments, play with triangulation and predict when both CDI needles will swing through centre.
5. Monitor NRST. Most aviation GPS units have a “NRST” button, allowing you to instantly see a list of the nearest airports. Watching this list will give you increased situational awareness, and it’s also fun to visually identify the airports you see on the list as you go by them.
4. If my engine quit right now… where would I land? Develop the habit of looking at regular intervals for an emergency landing spot. If it’s a road, is it clear of power lines? Are the trees alongside the road too close for comfort? How well traveled is the road? If it’s farm land, are there furrows to be considered? Or, if it’s rocky, raw desert, which surface is going to give me the best chances of walking away after the landing? If my aircraft flipped over during landing, how would I escape? It’s time well spent.
3. So, if my engine did quit… what speed would I immediately establish? Vglide is the speed which produces the farthermost glide if you were to lose power. During cruise, pull out the POH and confirm the Vglide speed. Then, commit it to memory. On most aircraft, it will be roughly half way between Vx (best angle of climb) and Vy (best rate of climb). Vglide speed increases with weight, and the published speed is likely computed for a max gross weight configuration. Is your best glide speed a knot or two less since you’re under gross? Know this number; it might save your life in an emergency.
2. Turn off the GPS. If you’re running a GPS, then turn it off or disable it for a bit. Look outside for visual cues – mountain tops, highways, power lines, railroad tracks – and match them to your chart. Then make a guess at your precise location and turn the GPS back on to see how close you were. If your GPS ever fails, then by occasionally having taken this challenge, you’ll feel more comfortable navigating solely by the chart.
1. Enjoy the flight. During the short golden age of powered flight, only a select few of us have the aptitude, ability and budget to be a PIC. This puts pilots in an elite group of human beings. Our privilege to fly at will could be threatened in the future by technological changes, personal budget, health, and even political climate – so pause for a moment and consider how fortunate we are to be pilots. We’ve got it so good!
Acknowledgements: AIR FACTS/John Zimmerman
A check-ride is always a stressful time for student pilots, as months of preparation culminate in a big test and hopefully a new certificate. It’s also a time when new pilots go from the clearly defined instructor-student relationship to the much fuzzier examiner-applicant relationship. Who’s in charge? The simple answer is the applicant, but an accident from late 2013 shows how tricky this question can be in real life. It also offers some lessons for all pilots.
The student pilot wasn’t going far in his rented Cessna 182, just 20 nm to a neighboring airport to meet a designated pilot examiner for his Private Pilot practical test. Unfortunately, the weather wasn’t cooperating, with a 600 ft. overcast and 4 miles visibility at his departure airport. The pilot called the examiner to discuss the weather, and the accident report included the following.
According to the Examiner, the student pilot called him on the morning of the accident and informed him there was a cloud deck at his departure airfield. He told the student that the cloud deck was probably a thin layer which would burn off, and that he should make the flight after the weather cleared up.
How this was interpreted by the pilot we’ll never know, but a short time later surveillance cameras at the airport show the 182 departing. The airplane flew just two miles on runway heading before crashing and killing the pilot. Examination of the airplane did not show any mechanical malfunctions or pre-impact failures. It appears to be a simple VFR-into-IMC accident.
Unlike some of these scenarios, the pilot didn’t stumble into ever-worsening weather. He was aware of this as demonstrated by his phone call to the examiner. So why would he launch into weather that was obviously unsafe for VFR flight?
The report makes note of the student’s known “gung-ho” personality, suggesting he was not afraid to take some risk. He was a successful, goal-oriented person who viewed aviation as a way to support his business, and his flight instructor had previously warned him about trying to “push too hard” to complete a trip.
So, on the surface this may sound like a reckless pilot who did not recognize his limitations, which may be part of it but other details suggest this to be an oversimplification. According to the CFI the student was feeling self-imposed pressure to complete his flight training, and this combined with his personality created the possibility of a potentially unsafe flight.
With that in mind, the examiner’s comment about the cloud deck burning off seems like the final straw. Here is a much more experienced pilot suggesting that the clouds are not a major problem, since they will not last long. While the examiner clearly said he should not fly until after the weather cleared up, the student may have taken that as encouragement to make the trip. He may have heard what he wanted to hear. And it was only a 20 mile flight.
Regardless of the pilot’s thinking, this accident is a reminder for all pilots that only the person controlling the yoke is pilot in command. That authority cannot be outsourced to anyone else and whilst saying “No”, even to implicit pressure or harmless suggestions, is sometimes hard to learn, it’s a life-saving skill, which faces pilots of all experience levels.
- When a controller says there’s a gap in the weather but you’re not sure, do you resist that subtle pressure?
- When a mechanic says the airplane is ready to go but you have your doubts, do you trust your own judgment?
- When a flying buddy says the weather is good enough to go but it’s below your personal minima, do you stand firm?
These are all hard questions, and of course the right answer is not necessarily to cancel every flight at the first sign of trouble. But there is only one vote that counts in the go/no go decision: that of the PIC. Guard that power jealously.