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Air Combat Basics:
The Scissors Maneuver
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Section Four The Rolling Scissors
Up until now, we have focused this
article on the Flat Scissors. But there is another type of
scissors that can be flown
the Rolling Scissors. In terms
of complexity, the Rolling Scissors is considerably more difficult
to fly in a simulation. Why? Because of the BFM skills involved
and the view management problems posed by the maneuver. This
section will briefly touch upon this type of scissors with
the emphasis being placed on BFM and view management.
The Vertical
Aspect Of The Rolling Scissors. Earlier, we mentioned
that the Flat Scissors was typically flown in the horizontal
plane. The Rolling Scissors may be flown in any plane
often
times, the vertical. Because of this, you may see the maneuver
referred to as the "Vertical Rolling Scissors".
We also noted that the adversaries
tended to fly the Flat Scissors in the same plane of maneuver.
By flying "in-plane", we mean that the two adversaries
tend to keep their lift vectors oriented in the same general
direction to produce two flight paths that tend to "overlap".
The Rolling Scissors differs in this respect. While both adversaries
tend to follow somewhat of the same vertical path, they deliberately
maneuver "out-of-plane" to minimize their forward
velocity and accentuate their relative energy capabilities.
The primary factor in winning the Rolling Scissors fight is
the optimization of our energy state relative to the bandits
position. What makes the Rolling Scissors different is the
increased importance of energy and the different use of the
sims views.
Energy
Use In The Rolling Scissors. Heres a side view
of a Rolling Scissors. The plane of maneuver is "vertical"
to the horizon for ease of discussion.
The maneuver typically begins with
the bandit overshooting the defender while attempting an attack
from above. The defender responds to the overshoot by pulling
"up" and then reversing to put his lift vector on
or behind the bandit. The bandit elects to join the scissors
by pulling back "up" after his overshoot
now
the battle is joined.
The Effect
Of Gravity. In a Flat Scissors, the effect of gravity
is relatively constant since the plane of maneuver is "horizontal".
In a Rolling Scissors, since the adversaries are either going
"up" against gravity or "down" with it,
gravity plays a more significant role in how the planes accelerate
(or bleed energy) as well as affecting turn performance (how
the one g of gravity adds to or subtracts from turn rate and
radius). Gravity will add to your turn performance (smaller
turn radius) when coming over the top
and will tend to
widen your radius and lower your turn rate when pulling up.
When climbing or descending, you want to unload to no more
than one g to minimize drag and allow you to maintain or gain
energy.
While the Flat Scissors is basically
a slow speed contest, this is not necessarily the case in
a Rolling Scissors. While the overall objective is to minimize
forward velocity, velocity in the climb and descent is used
to control turn performance and climb potential. Victory in
the Rolling Scissors goes to the adversary who can best manage
his energy
in this situation, getting "slow"
may not be a good idea!
How does "energy" play a
role in winning the Rolling Scissors? Primarily in providing
the "oomph" that allows one adversary to fly a longer
climbing leg than the other. A higher energy state allows
the pilot to orient his flight path more into the vertical,
and it allows him to remain in the climb longer. The adversary
that cannot zoom as well is forced to roll back towards the
ground
in doing so, he is pushed forward.
Perhaps the best way of explaining
this maneuver is to go step by step through a typical Rolling
Scissors
and point out the various considerations as
we go along.
A Typical
Rolling Scissors. A Rolling Scissors is usually entered
from two situations
one, as a response to an overhead
attack, or, two, from a flat scissors situation where an altitude
separation exists between the attacker and defender. Well
use the first as our example. Some of you might recognize
this example
its from Shaws excellent book,
Fighter Combat. Ill add some minor notation to amplify
the points of emphasis. Disregard the exact position of the
aircraft in the following diagrams. I have placed the red
numbers on the aircraft ribbons at the place where the aircraft
should be as described by the text.
The Overhead
Attack. You pick up the bandit in your high six as
he dives down for a gun attack. You begin a hard right turn
into the bandit to force his nose into lag. You add aileron
as necessary to roll slightly away from the bandits
flight path
this takes you out of his gun line. This
is Point 1.
Your hard turn produces an overshoot.
As the bandit crosses your six, you elect to enter the scissors
by rolling back left to begin a climb. You continue to pull
up as you pirouette in a left roll to watch the bandit as
he overshoots to your left side. Once you have your climb
angle established, you unload to maximize your zoom potential
and continue rolling as needed to keep the bandit in sight
out of the top of your canopy. As you do this, you see the
bandit has begun a climb as well and is pulling back towards
you. At this time you are "canopy to canopy" with
the bandit
you both have your lift vectors on each other
(Point 2).
Now, you continue to analyze the bandits
flight path and roll as necessary to point your lift vector
behind the bandit. You then add back pressure to begin pulling
your nose smoothly to his six. The bandit is also pulling
into you
this results in your flight paths tending to
come nose-on to each other (Point 3).
At this point, you and the bandit
are nearing the top of your climbs with your flight paths
converging. Now is when you want to pull down aggressively.
Do so and you will "make angles" with a lead turn.
Use full power, flaps as needed, and max available g to produce
the maximum turn rate in your pull down. Roll as needed to
keep your lift vector pointed behind the bandit. Point 4 is
the pull down.
Once you have your nose down, unload
the g, go full power, retract the flaps if appropriate, and
accelerate. Now watch the bandit as you check your speed.
In our example, the bandit is going to make a lead turn in
the vertical as we dive down on him (Point 5). He will signal
this by beginning his pull down before we pass his 3/9 line.
Does this mean hes going to use this lead turn to gain
an advantage?
Maybe
but it will only be illusory,
because by cutting short his climb into the vertical, hes
going to lose a little overall energy potential. We continue
our descent and throttle back to keep our speed around corner.
As the bandit comes "over the top", we wait for
him to get his nose "buried"
well established
in a nose down attitude
and then we set the hook! Boom!
Back up into the vertical we go!
As you begin your second pull up,
do not use max g. Instead use your best sustained g
that
will be about 3-5 gs for the typical fighter. Level your wings
and pull up
as before, pirouette roll as needed to keep
pointed at the bandits six. Do not fly out in front
of the bandit. Point behind him! Once you have your nose up,
then unload again and use your airspeed to gain altitude.
In your climb, you will see the bandit
attempting to stop his dive and pull up and into you. This
series of rolling pull ups and downs is what makes the maneuver
a Rolling Scissors. Assuming each pilot flies good BFM, the
victor in this contest will go to the plane that has the better
energy sustainability characteristics. The pilot of that plane
will be able to fly extended pull ups and tighter pull downs
that will tend to force the other plane forward along the
axis of the scissors.
View Use
In The Rolling Scissors. It is not unusual for the
Rolling Scissors to maintain one direction of roll. As each
adversary rolls about the other, they will look at each other
out of the tops of their canopies. As they roll to point behind
each other, they will see each other out of the side of the
canopy that is the direction of roll. This tendency to look
only in one direction is different from the bi-directional
view technique used in the Flat Scissors.
Separating
from the Rolling Scissors. Your best chance of a successful
separation is when you have pulled down into your nose low
acceleration attitude. Unload to one g or less and dive out
of the fight. Roll unloaded as needed to watch the bandit.
Be ready to counter any follow-on attack.
Conclusion
Here are the main points to take from
this discussion:
- Enter a scissors with caution.
Once in, it will be difficult to get out.
- Generally speaking, the lower wing
loaded fighter has the advantage, pilot skills being equal.
- The Flat Scissors is a slow speed
contest. Be proficient at slow speed flight techniques.
Know how to use flaps.
- The Rolling Scissors is an energy
fight. Know your corner velocity and energy gaining and
sustaining techniques.
In any case
this is what
its all about
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