Missed Approach
(continued) When clouds are added to the picture the missed approach is related both to landing considerations and to weather.
For best results it is best to fly every instrument approach with full anticipation of a missed approach. There are many things that can lead to a miss. If the approach is being hand flown and at 1,000 feet above the ground everything is not well in hand, that's a good place to start into the missed approach. Just remember that the missed approach procedure begins at the missed approach point, usually the end of the runway on non-precision approaches, so you don't start the published procedure until reaching that point.
Another thing to consider on a non-precision approach is that the point at which the approach becomes impossible is not at the missed approach point but a distance from the end of the runway. With GPS we have distance to the end of the runway and when that number equals the visibility minimum for the approach, successfully completing the approach is in doubt unless the runway is in sight.
This is illustrated in the minimums for some LNAV/VNAV and LPV approaches. On these, if the decision height is, say, 400 feet, the visibility minimum will be higher than the usual one mile for a straight-in LNAV approach. Why? If you are following the calculated (usually 3-degrees) approach slope to the runway you'll be more than a mile from the end of the runway when reaching the decision height. There are many non-precision approaches where the minimum descent height makes it impossible to make a straight-in approach if the visibility is minimum, and the criteria for minimums on the GPS approaches with vertical guidance addresses this.
Another reason to always anticipate a missed approach is weather. It might be reported as above minimums at the airport, but that offers no guarantee of what the weather will be along the final approach course. Under Part 91, not for hire, we can fly approaches when the visibility is reported as below the published minimums because our rule says the flight visibility has to meet the criteria, and flight visibility is based on what you see ahead and not what is observed on the ground.
What's legal isn't always safe and there is a long history of fatal accidents related to approaches in low weather. This is especially true when multiple approaches are flown by a pilot who is really trying too hard to make possible the impossible.
There are also accidents on missed approaches, either when the pilot doesn't aggressively fly into the missed approach procedure or loses control of the airplane because of the distractions found in a missed approach. On the latter, if every approach is begun with a firm plan for what comes next in the event of a missed approach, things will be better. Have an answer in mind for the controller's question about your intentions after you miss an approach and the rest of your day will go better.
Next, consider the flying technique involved in a missed approach. One thing we can do to make missed approaches easier is to fly the approach with takeoff flaps and at the initial climb airspeed. That means you have to calculate extra runway but most ILS runways will allow this in piston singles or light twins. If an approach flown like that is missed, the airplane will be in the climb configuration from the git-go on the missed approach, leaving only the application of power and the gear to be retracted if the airplane is so equipped.
A shorter runway served by a non-precision approach probably won't allow such an approach, but the minimums would likely allow the selection of full flaps after the runway is in sight and the landing is assured. When you are practicing do look at missed approaches frequently.
Finally, a good practice is to eschew approaches that have a high likelihood of becoming missed approaches. If the weather is really low, do you want to fly within 200 feet of the ground while fully enveloped in cloud? There is a lot of difference between a professional flight crew's qualifications to do that and the average instrument rated pilot's qualifications to do that. Our training falls far short and doing it alone has fewer safeguards and backups. That's why our record here is so bad, and their record is so good.
Choosing your approach battles carefully can reduce a lot of the known risks. If your destination has weather or wind or runway length problems there is surely another airport available with better conditions.
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