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**Jim[_14_]**

On 5 Mar 2007 17:34:40 -0800, wrote:

On Mar 5, 10:11 am, Mxsmanic wrote:
Unfortunately I tend to be impatient in the sim and I'm often still not
aligned even as I cross the threshold, unless I planned to land at that
airport well ahead of time. I usually come in fast because I'm making rather
risky turns on the approach and I don't want to come too close to a stall.

If not aligned at the threshold in a real plane, you should go around.
You should strive to become aligned with the centerline soon after
turning onto final, and then hold it there. It can be done with
practice. Don't forget you'll need a crab angle to take care of
crosswind.

How do you trim to a speed? Especially when you are adjusting power?

Don't try to do both at the same time. Hold power constant, and
adjust pitch with the yoke until you are at your desired airspeed,
then apply trim until you can release the yoke without the pitch
attitude (and therefore, airspeed) changing. Then with the airspeed
stabilized, adjust power to change the rate of descent, small changes
in power won't affect your airspeed.

What airspeed do you choose for landing?

You need the proper speed for your aircraft. If it's not available in
the Pilot's Operating Handbook, then use an old rule of thumb, set the
airspeed equal to 1.3 times the aircraft's stall speed. Your aircraft
should be slowed to this speed by the time you turn final, and then
hold it precisely at that speed. The normal way to hold airspeed is
by trimming to that speed in pitch.

Hmm ... I had not thought of working out numbers that I could reuse. Each
approach has been trial and error but I haven't been noting anything. I guess
I'll have to write stuff down (or at least try to remember it). I do have a
few things memorized for the Baron, after hundreds of hours in it, but not as
much as I probably need or could use.

You will not achieve consistent landings until you can fly a
stabilized approach. To do this, you need to discover the numbers for
your aircraft, and then use them. To find them, I suggest you conduct
some experiments in the sim. Set up your aircraft in level flight on
downwind, constant speed, gear down, at 1000 ft AGL, with a medium
power setting. When opposite the numbers, lower your flaps to their
first setting (or 10 deg) and reduce power until you stabilize at a
500 ft/min descent rate with the airspeed at 1.5 times stall speed.
Record the power setting and airspeed. Use those numbers for your
initial descent from the pattern. After 30 seconds, turn base and
lower flaps to the second setting and set pitch for airspeed = 1.4
times stall speed. Then turn final, lower flaps completely, and set
pitch for 1.3 times stall speed. Fly it like this until you hit the
ground. If you land long, then reduce power a little more next time.
If you land short, add a little power next time. Keep iterating until
you zero in on the right numbers.
Excellent advice on all points. Only thing I would add is to use these
steps in basic trainer such as C172 until proficient, as in real life
you must crawl before you can walk. Flying a complex aircraft in
simulation is task intensive and frustrating. Flying the C172 will
allow you to master the fundamentals, then move on to more complex
aircraft. Also to compute the approach speed use the upper limit of
the white arc on the airspeed indicator as the number you use to
multiply by 1.3 to give your final approach speed. As you cross the
numbers cut the throttle and flare. Be careful not to float or balloon
in ground effect. If you do balloon add a bit of power to stabilize
and cut the throttle again and flare to landing. Hope this helps.
--

Jim in Houston
osPAm
Nurse's creed: Fill what's empty, empty what's full,
and scratch where it itches!! RN does NOT mean Real Nerd!