Tweaking the throttle on approach

chris writes:

A good landing starts with a good approach. If you don't get your
approach sorted out you are almost certain to stuff the landing up.

I know. I guess I'm just impatient. I wouldn't be that way in real life, but
in the sim it's often different, as one doesn't always have the time to fly
for a long period, and I like to practice take-offs and landings at tiny
airports as I encounter them.

A good airspeed for crossing the fence is VSo x 1.3. Find out what
your stall speed is, multiply by 1.3 and you have your speed at short
finals. You can add a bit for the early part of the approach, for a
172 you might use 70-80 kt on approach, reducing to 55 kt on short
finals.

Hmm ... well, I've been coming in at around 100 kts, which just happens to be
the full-flaps Vso plus 30%, as you suggest (in the Baron, Vso is 75 kts). So
I guess I haven't been going as fast as I thought. After reading what some
people suggest--that the aircraft should stall as it lands--I thought that
perhaps I was coming in too fast.

Usually I'll stay at right around 100 or so practically to touchdown. As I'm
gliding above the runway I'll reduce power and let the aircraft settle on its
own. It seems to be very smooth. The only disadvantage is that I need a
longer runway. But most runways are more than long enough for my small plane,
so there's no reason to rush down to the ground that I can see.

Whatever light aircraft you fly will be similar, can't speak
for the heavies though.. If you use much more than 80kt on approach
it can be difficult to get rid of the speed while still descending.

I try to come in with a good rate of descent at 100. Then, when I'm close to
the runway and coming into ground effect, I stop the descent, which causes my
airspeed to drop rapidly. As that brings me down, I progressively flare until
the wheels touch.

In heavies it's easier to some extent because the FMC will tell you what speed
to make on the approach. And if you autoland, you just set the MCP for that
speed or slightly above (136 in a lightly loaded 747-400) and it comes out
fine. The main trap with heavies is that you can't change your configuration
at the last minute--you have to be aligned and stable in your approach quite a
distance out, because last minute tweaks can be difficult and dangerous.

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