Learn to Turn
Posted: Fri Sep 24, 2021 5:50 pm
This is an odd subject, because I am sure most pilots are pretty certain
they know how to turn. "There's a steering wheel in the airplane", they
will tell me. "It works just like my car!".
Perhaps not.
First, you need to learn how to do level turns, at varying airspeeds. Pilots
are amazingly bad at this. Slow flight/stall/spin are supposedly three
different and very basic maneuvers required to pass the PPL, but pilots
are often afraid of this kind of slow speed maneuvering and avoid it, until
they can't, and then bad sh1t happens.
So, as Arlo Speer told me, time for some remedial training. Go out to the
practice area at 4000 AGL, HASEL check, carb heat on, power off, flaps 20
in the white arc, then back to to 1800 RPM or whatever is required to maintain
altitude. Trim nose up.
On that subject, TC will tell you that altitude control in slow flight is important,
and that's simply not true. It's your lowest priority. If you start slow flight at
4000 AGL and descend to 3000 AGL and get some really excellent high alpha
practice, that's what's important.
TC will tell you that you need to precisely control altitude in slow flight so that
you can fly an ILS on the back side of the power curve, but AFAIK I'm the only
person here that does that, so don't worry about it.
Drive around with the stall warning horn in. Don't stress about the altitude.
Do some turns. This is about turns, right? If you drop a wing, don't pick it
up with the "steering wheel". Deal with that by decreasing alpha with forward
stick and maybe a touch of opposite rudder.
Ok. In addition to level turns at normal speeds (what you do every flight) we
now have done some training at level turns at slow speeds.
Now for some more interesting level turns at cruise speed. You are probably
used to 45 degrees of bank, so start with that. 180 degrees of heading change,
then reverse and go the opposite 180 degrees. Back and forth. Try to maintain
altitude, but it's really about pitch attitude or lift production. Remember the illusions
caused by you sitting on one side of the airplane. And you will need a little extra
power to maintain airspeed with 45 degrees of bank.
Now for 60/2. Roll into 60 degrees of bank and full power. Glance at the ball,
but look outside. Back and forth, 180 degrees of heading change, over and over
again. If you have something sporty, step it up to 75/4. Builds character.
Ok, after a lot of effort, you might be competent at level turns at varying airspeeds.
Remember this formula. Write it down. Tatoo it on your goddamned forearm:
Vs(G) = Vs(1g) x sqrt(G)
Math For Pilots: the fast you go, the more G you can pull before you stall. And
the slower you are, the less G you can pull before you stall. In a 75/4 turn, your
stall speed will be double what it shows on the ASI.
Note that the above formula is easily derived from the lift equation on the back
of an envelope between courses at Applebee's. I've done it, and I'm a below average
pilot, so ask any TC Inspector to derive it for you. Look at the left hand side of any
Vn diagram.
After you address your remedial pilot skill deficiencies, the next thing you need
to learn to do, is change altitude while you turn. While this sounds simple, pilots
year after year come to grief attempting this.
A maneuver that FAA requires for the CPL (but TC forbids) is the lazy-eight.
Let's talk about the lazy eight. You need to learn to master it. It is basically
back-to-back wingovers. What is a wingover? Easy.
From cruise altitude/airspeed/power setting, start a climbing turn either right
or left. You must climb and turn at the same time. Here's the tricky bit: you
need to time it, so that at the apogee of the maneuver you are at 90 degrees
of bank, with very light G, ball in the center. You are ballistic, like a pop fly baseball
arcing up, then down again. You are not asking the wings to produce any lift,
but the G is very light and positive to keep the fluids in the right place and the
grit on the floor and out of your eyes. Nobody vacuums the carpet. Ever.
From the apogee, start a descending turn, perfectly symmetrical with your first
half, so that you exit at the same altitude and airspeed as your entry, but your
heading will be 180 degrees changed.
This is a wonderful maneuver. You can visualize it with a piece of string on
the table. Lay it out in a "U" and pick up the center. That's a wingover. If you
master the wingover, you will be able to turn the aircraft at very slow speeds,
which is an incredibly valuable skill.
For completeness I should mention that you can fly a wingover with the same
climbing-half turn entry, but when you roll out, don't descend. You will be very
slow at high alpha with some pitch attitude on to try to maintain altitude at the
end. That's a "chandelle" and is neat, but pilots are notoriously poor at high
alpha flight and the wingover has symmetry, and symmetry is good. You can
do wingover after wingover endlessly, and from the side, it looks like an 8 lying
on it's side, hence the "lazy eight" term.
Pop Quiz: In any aircraft, I am turning base. I unload the wing so that zero G is
showing on the accelerometer. With 80 degrees of bank on, what is my stall
speed?
Let's plug some numbers in the above formula that you've already forgotten:
Vs(0G) = Vs(1g) x sqrt(0)
they know how to turn. "There's a steering wheel in the airplane", they
will tell me. "It works just like my car!".
Perhaps not.
First, you need to learn how to do level turns, at varying airspeeds. Pilots
are amazingly bad at this. Slow flight/stall/spin are supposedly three
different and very basic maneuvers required to pass the PPL, but pilots
are often afraid of this kind of slow speed maneuvering and avoid it, until
they can't, and then bad sh1t happens.
So, as Arlo Speer told me, time for some remedial training. Go out to the
practice area at 4000 AGL, HASEL check, carb heat on, power off, flaps 20
in the white arc, then back to to 1800 RPM or whatever is required to maintain
altitude. Trim nose up.
On that subject, TC will tell you that altitude control in slow flight is important,
and that's simply not true. It's your lowest priority. If you start slow flight at
4000 AGL and descend to 3000 AGL and get some really excellent high alpha
practice, that's what's important.
TC will tell you that you need to precisely control altitude in slow flight so that
you can fly an ILS on the back side of the power curve, but AFAIK I'm the only
person here that does that, so don't worry about it.
Drive around with the stall warning horn in. Don't stress about the altitude.
Do some turns. This is about turns, right? If you drop a wing, don't pick it
up with the "steering wheel". Deal with that by decreasing alpha with forward
stick and maybe a touch of opposite rudder.
Ok. In addition to level turns at normal speeds (what you do every flight) we
now have done some training at level turns at slow speeds.
Now for some more interesting level turns at cruise speed. You are probably
used to 45 degrees of bank, so start with that. 180 degrees of heading change,
then reverse and go the opposite 180 degrees. Back and forth. Try to maintain
altitude, but it's really about pitch attitude or lift production. Remember the illusions
caused by you sitting on one side of the airplane. And you will need a little extra
power to maintain airspeed with 45 degrees of bank.
Now for 60/2. Roll into 60 degrees of bank and full power. Glance at the ball,
but look outside. Back and forth, 180 degrees of heading change, over and over
again. If you have something sporty, step it up to 75/4. Builds character.
Ok, after a lot of effort, you might be competent at level turns at varying airspeeds.
Remember this formula. Write it down. Tatoo it on your goddamned forearm:
Vs(G) = Vs(1g) x sqrt(G)
Math For Pilots: the fast you go, the more G you can pull before you stall. And
the slower you are, the less G you can pull before you stall. In a 75/4 turn, your
stall speed will be double what it shows on the ASI.
Note that the above formula is easily derived from the lift equation on the back
of an envelope between courses at Applebee's. I've done it, and I'm a below average
pilot, so ask any TC Inspector to derive it for you. Look at the left hand side of any
Vn diagram.
After you address your remedial pilot skill deficiencies, the next thing you need
to learn to do, is change altitude while you turn. While this sounds simple, pilots
year after year come to grief attempting this.
A maneuver that FAA requires for the CPL (but TC forbids) is the lazy-eight.
Let's talk about the lazy eight. You need to learn to master it. It is basically
back-to-back wingovers. What is a wingover? Easy.
From cruise altitude/airspeed/power setting, start a climbing turn either right
or left. You must climb and turn at the same time. Here's the tricky bit: you
need to time it, so that at the apogee of the maneuver you are at 90 degrees
of bank, with very light G, ball in the center. You are ballistic, like a pop fly baseball
arcing up, then down again. You are not asking the wings to produce any lift,
but the G is very light and positive to keep the fluids in the right place and the
grit on the floor and out of your eyes. Nobody vacuums the carpet. Ever.
From the apogee, start a descending turn, perfectly symmetrical with your first
half, so that you exit at the same altitude and airspeed as your entry, but your
heading will be 180 degrees changed.
This is a wonderful maneuver. You can visualize it with a piece of string on
the table. Lay it out in a "U" and pick up the center. That's a wingover. If you
master the wingover, you will be able to turn the aircraft at very slow speeds,
which is an incredibly valuable skill.
For completeness I should mention that you can fly a wingover with the same
climbing-half turn entry, but when you roll out, don't descend. You will be very
slow at high alpha with some pitch attitude on to try to maintain altitude at the
end. That's a "chandelle" and is neat, but pilots are notoriously poor at high
alpha flight and the wingover has symmetry, and symmetry is good. You can
do wingover after wingover endlessly, and from the side, it looks like an 8 lying
on it's side, hence the "lazy eight" term.
Pop Quiz: In any aircraft, I am turning base. I unload the wing so that zero G is
showing on the accelerometer. With 80 degrees of bank on, what is my stall
speed?
Let's plug some numbers in the above formula that you've already forgotten:
Vs(0G) = Vs(1g) x sqrt(0)
