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Old 31st Aug 2007, 17:34
  #39 (permalink)  
AirRabbit
 
Join Date: Apr 2005
Location: Southeast USA
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Hey Ski Wave:

I certainly understand your position. I am not saying that what I’ve described is what you have to do each time you descend through 50 feet. After you’ve worked through what is happening – you won’t even have to think it through. Example – how many times do you check your rear-view mirror driving to work? But, I’d bet you do it and take what ever action you need to take (if any) without thinking about it.

Like I was trying to describe to PP, anything you do sounds a lot more complex than actually doing it when it is described in any detail. And within a reasonably short time, you will not realize that you’re doing all that you thought was so complex when you started. I am advocating achieving level flight attitude (which should be somewhere between 3 and 6 degrees of pitch – depending on the weight of the airplane), and doing so somewhere between 3 and 5 feet above the runway at the end of the flare, with an airspeed something on the order of 1.1 to 1.2 times the stalling speed in that configuration and weight. The more you land, the more you’re going to understand the sight picture you want to see; and the more you’re going to be able to “feel” what level flight feels like. I think it important that YOU pick whatever YOU use to determine level flight – some look at the departure end of the runway; others place certain windshield bolts on a tree line or horizon line; others use a side-glance at the distance to the runway edge (paint stripe); others use the windshield bolt and runway edge (paint stripe) match-up; and there are probably dozens of other “techniques” that work for different pilots. I don’t want to teach you to recognize level flight the way I recognize it. I want you to pick what seems easiest and most natural for you.

The very best way isn’t available to many of us any longer – that is to fly level down the runway at a 5-foot height and proper speed (1.1 – 1.2 Vsl). But, you CAN do that in a simulator, and do it quite nicely – assuming your instructor or the simulator guys are agreeable. Using the simulator you can try it from landing weights that run the range from max to minimum. You can do it for various flap settings. Use whatever cues you need to maintain level flight. You ARE allowed to “cheat” if you desire. Raise the nose the recommended number of degrees to see if that is enough if you want. Crosscheck the vertical speed indicator if you want. Check the attitude indicator and/or the airspeed indicator, if you want. Look at the end of the runway. Look directly over the nose. Look out the side windows. Determine what spot on the runway surface that does not move up or down in the windscreen (where you are actually headed). Take into consideration your peripheral view of the world. Use the tiny burble you get in the column as the tail plane settles into ground effect. Use whatever you feel most comfortably and most accurately gets you to achieve level flight attitude. What attitude is that? Well, you’ll have to experiment a couple of times. You’ll also have to add some power – not a lot – in order to maintain the airspeed. Fly down the length of the runway way. Crosschecking whatever you desire to see and checking all of the possible confirmations available to you to be sure that you are, indeed, in level flight. This is to be able to recognize the attitude. If you change airspeed the attitude will change as well. In a rather short time you will determine what you are most comfortable with taking into your scan to determine that attitude.

After you’ve done this a few times (some people need 2 or 3 passes – some either like it or want to experiment and take 10 or more times – not a real cost in the simulator). The next time do exactly the same thing, but instead of adding power, pull it off. Change nothing else. Do not let the attitude of the airplane change – don’t increase it, don’t allow it to decrease with the reduction of power – this will likely require a bit of an increase in back pressure, but don’t raise the nose – use just enough back pressure to keep it from falling. Don’t stay in that attitude beyond 3 seconds. Usually you’ll be close enough to the ground that you’ll touchdown in less than 2 seconds. The landing will likely be “firm,” but not uncomfortably so. Once on the ground and the spoilers have deployed, fly the nose to the ground quickly but smoothly. Reverse thrust is used according to the situation and, obviously, in accordance with your company procedures.

The value here is actually multiple: If you add power in this condition – you’ll gain forward speed rather quickly and level off without having to do anything to the nose position. If you need to climb slightly, add just a bit more power, you don’t need to adjust the nose position. Both of these are valuable pieces of information should you ever have to recover from a bounced landing. We’ve all done them – so will you. Should you need to go around, as you add go around thrust and increase forward speed, you will begin to climb slightly, which is an advantage in tail clearance when you rotate to the takeoff / go-around attitude. Also, once you start perfecting your crosswind landing techniques, you’ll already have this part of the puzzle worked out. Now all you’ll have to get is the timing of pressuring the nose around to line up with the runway during the flare and, at the same time, be able to finesse the amount of “aileron into the wind” that you might need to keep that wing from rising.

So that I don't incur the ire of those who may read this - I am not advocating that you do ANYTHING contrary to what your instructors have taught you to do. If you have the opportunity to check this out ... do so ... I'd be interested in hearing what you have to say.

Cheers!
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