Greetings!I know we kid guys about bounced landings during our Saturday informal flights, but the consistency of landing problems leads me to believe a few pointers may be appropriate.
Bounced landings can be caused by any or all of the following:
- Too much vertical velocity and bouncy landing gear
- Improper flare technique (usually overcontrolling the airplane)
- Trying to land with too much airspeed and/or power
I believe the most common problem we're seeing is the latter. There are a combination of factors that would make this true:
- The flight plans we've been using on these flights have not included POD (Point of Descent) or DP (Descent Point). As a result, pilots have been coming in high and hot (fast). As you know, if you point the nose down to make the runway, your airspeed will either remain high or increase. Trying to land at too high of an airspeed will allow the wings to remain flying even though you want to land. A DP would reduce this problem and make it easier to fly a stabilized approach (see below). The way you come up with a DP is figure out how many miles it would take to descend at a constant rate of descent. For example, if you're cruising at 6,500 feet down to a pattern altitude of 1,500 feet, you need to descend 5,000 feet. A comfortable rate of descent in a C172 is about 500 to 750fpm. So to descend 5,000 feet would take 10 minutes @ 500fpm. At your descent airspeed, you can figure out how many miles you'd cover in 10 minutes and backtrack a point on your flight plan to place a DP.
- We change aircraft fairly regularly. With the ability to fly many more different aircraft in FS than you could possibly fly in real life, we tend to fly aircraft that are not all that common from one to the other. As a result, the performance capabilities and, more importantly, V speeds are very different. One of the problems with flying 3rd party aircraft is the POH information is usually not available (especially if you're flying something old or exotic). So if you try and land an aircraft at too high of an airspeed, well, see above.
- I realize that some of the guys that fly with us on Saturdays are not involved with real flight training, so the concept of stabilized approaches may be new to you. The basic idea is to fly your approach to landing at a constant airspeed. Of course the aircraft you're flying, and the landing weight of the aircraft will change what your airspeed should be. To complicate matters, depending on whether you're on an IFR approach or landing from the pattern will change how fast you should be going. For example, an IFR approach in a C172 should be made at about 90 knots, with a Vref (landing reference speed - which is a term typically only used in turbine aicraft, but the concept can be used here and will help later on when you fly turbines) between 60-70 knots. Just FYI, if Vref is not available, use 1.3 Vs (stall speed - clean configuration) as a rule of thumb and that should get you in the ballpark for aircraft flown in FS. Landing at Vref will allow you to land with a minimum of excess airspeed, and hopefully that'll help reduce the "number" of touchdowns made per landing.
Let's see if this helps reduce airport dramas and runway repairs.
Hope this helps!
Ben
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